Nuclear Physics Seminar, Fall 2017 / Spring
2018
The regular experimental and theoretical
nuclear physics seminar take places Thursdays at 4h00PM. Lunch seminars are also held from time to time on the rest of the days at 1PM.
The venue is either the Gerry Brown Room (Physics Building, room C133), or the Peter Paul Room (Physics Building, room C120). In addition to this seminar series, the Center for Frontiers in Nuclear Science (CFNS) organizes seminars twice a month (1st and 3rd Thursday of each month), which take place at Stony Brook University and BNL alternately. The schedule of the CFNS seminars can be found under the center's website, http://www.stonybrook.edu/cfns/. For suggesting speakers, please contact juan.torresrincon@stonybrook.edu.
Google Calendar version: https://calendar.google.com/calendar/embed?src=stonybrook.edu_v5puq1gb0braomja25hqhjnf5g%40group.calendar.google.com&ctz=America/New_York
(Calendar ID: stonybrook.edu_v5puq1gb0braomja25hqhjnf5g@group.calendar.google.com)
Fall 2017 

Time 
Speaker 
Title 
Host 
Notes  January 17, 1h00PM, Thursday (Room C133)
 Andrey Sadofyev (LANL)
 TBA
Abstract: TBA
 Juan TorresRincon
  December 5, 1h00PM, Wednesday (Room C133)
 Alexander Turbiner (UNAM)
 Choreography in (non)Newtonian gravity
Abstract: By definition the choreography (dancing curve) is the trajectory on which n classical bodies move chasing each other without collisions.
The first choreography (the remarkable Figure Eight) at zero angular momentum was discovered unexpectedly by C Moore (Santa Fe) at 1993
for 3 equal mass bodies in R^3 Newtonian gravity numerically. At the moment about 6,000 choreographies are known, all numerically
in Newtonian gravity. A number of 3body choreographies is known for LenardJones potential again numerically; it is proved
their existence for quarkonium potential.
Do exist (non)Newtonian gravity for which dancing curve is known analytically?  Yes, one example is known  it is algebraic lemniscate by Jacob Bernoulli (1694)  and it will be the subject of the talk. Astonishingly, Newtonian Figure Eight coincides with algebraic lemniscate
with accuracy 10^{7}.  Edward Shuryak
  November 15, 1h00PM, Thursday (Room C133)
 Rasmus Larsen, (BNL)
 Extracting topology from lattice QCD near Tc
Abstract: We report our study on the properties of the topological structures
present in the QCD medium around the critical temperature Tc. We use
dynamical domain wall fermion configurations on lattices of size
32^3x8 and detect
the topological structures through the zero modes of the overlap
operator. We explicitly show that the properties of the zero modes of
the QCD Dirac operator agrees well with that of calorons with
nontrivial holonomy. Different profiles of the zero modes
are observed, and when we change the fermionic boundary condition in
the temporal direction, the zero mode moves to another location . All of
this indicates the presence of instantondyons in the hot QCD medium
around Tc, where the distance between dyons control
the shape and extent of the zero modes.  Edward Shuryak
  November 14, 1h00PM, Wednesday (Room C133)
 Yakov Schnir (Trinity College, Dublin)
 Multisoliton solutions of the SkyrmeMaxwell
model in 2+1 dim  Edward Shuryak
  October 22, 1h00PM, Monday (Room C133)
 Alexander Gorsky (IITP, Moscow)
 Mobility edge in the Dirac operator spectrum and black hole horizon Abstract: We conjecture that a mobility edge in the spectrum of the Dirac operator in deconfined QCD corresponds to the nearhorizon region in the holographic description. Some evidences in favor of this conjecture will be presented.  Dima Kharzeev
  September 25, 1h00PM, Tuesday (Room C133)
 Jacob Sonneschein (Tel Aviv University)
 The decay width of stringy hadrons
Abstract: I will start with briefly describing the HISH (Holography Inspired Stringy Hadron) model and reviewing the comparison of the corresponding spectra of mesons, baryons, glueballs and exotic hadrons with the PDG experimental data. I will present the determination of the hadron strong decay widths. The main decay mechanism is that of a string splitting into two strings. The corresponding total decay width behaves as Γ = π/2ATL where T and L are the tension and length of the string and A is a dimensionless universal constant. The partial width of a given decay mode is given by Γ_{i}/Γ = Φi exp(−2πCm^{2}_{sep}/T) where Φ_{i} is a phase space factor, m_{sep} is the mass of the ”quark” and ”antiquark” created at the splitting point, and C is a dimensionless coefficient close to unity. I will show the fits of the theoretical results to experimental data for mesons and baryons. I will examine both the linearity in L and the exponential suppression factor. The linearity was found to agree with the data well for mesons but less for baryons. The extracted coefficient for mesons A = 0.095 ± 0.015 is indeed quite universal. The exponential suppression was applied to both strong and radiative decays. I will discuss the relation with string fragmentation and jet formation. I will extract the quarkdiquark structure of baryons from their decays. A stringy mechanism for Zweig suppressed decays of quarkonia will be proposed and will be shown to reproduce the decay width of Υ states. The dependence of the width on spin and flavor symmetry will be discussed. I will further apply this model to the decays of glueballs and exotic hadrons.
 Ismail Zahed
  September 18, 1h00PM, Tuesday (Room C133)
 Kiminad Mamo (SBU)
 DIS on "nuclei" using holography
   September 5, 1h00PM Wednesday (Room C133)
 Juan TorresRincon (SBU)  OnShell Effective Field Theory and the chiral kinetic equation Abstract: I will detail the derivation of the chiral kinetic theory for massless fermions using quantum field theory techniques. For this goal, we have developed the socalled onshell
effective field theory (OSEFT). This effective theory accounts for nearly onshell fermions and
antifermions, while the offshell degrees of freedom are integrated out.
This provides a systematic expansion of the Lagrangian in inverse
powers of the onshell energy. We derive the collisionless kinetic
equation for the fermion Wigner function, obtaining the necessary
corrections to reproduce the chiral magnetic effect and the consistent version of the chiral anomaly equation. The
Lorentz invariance of the OSEFT is analyzed by means of the
reparametrization invariance of the effective Lagrangian. Applying
reparametrization transformations to the Wigner function we
automatically obtain the peculiar Lorentz transformation of the
distribution function, originated by the socalled "fermion side jumps".    August 16, 4h00PM Thursday (Room C133)
 Yoshimasa Hidaka (RIKEN)
 Electric conductivity of hot and dense quark matter in a magnetic field Abstract: We discuss the electric conductivity of quark matter at finite temperature and quark chemical potential under a magnetic field B beyond the Lowest Landau level approximation. The electric conductivity transverse to B is dominated by the Hall conductivity. For the longitudinal conductivity, we need to solve kinetic equations. We numerically find that the longitudinal conductivity has only mild dependence on the chemical potential and the quark mass.
Moreover, first decreases and then linearly increases as a function of
B, leading to an intermediate B region which looks consistent with the
experimental signature for the chiral magnetic effect. We also point out that the longitudinal conductivity at nonzero B remains within the range of the latticeQCD estimate at B = 0. Reference Kenji Fukushima and Yoshimasa Hidaka, Phys. Rev. Lett. 120, 162301 (2018)  Juan TorresRincon
  August 9, 1h00PM Thursday (Room C133)
 Yuji Hirono (Brookhaven National Laboratory)  Dynamical aspect of chiral fluids
Abstract: Chiral fluids have been a fascinating subject in recent years. In this
talk, I’d like to talk about the dynamics of chiral fluids in the presence of dynamical electromagnetism. At longwavelength and
longtime limit, the dynamics of described by the chiral
magnetohydrodynamics. I will talk about how the chiral MHD is formulated as a hydrodynamic lowenergy theory. Based on that theory, the properties of excitations in chiral fluids are discussed. A
further coarsegrained description can be obtained as a theory of thin
vortex filaments in a chiral fluid. The dynamics of those filament is
found to be described by a modified version of the localized induction
equation, which can be mapped to the integrable Hirota equation. We
analyze physical properties such as the modification of solutions and
fluctuations around them.
 Juan TorresRincon
  June 28, 1h00PM Thursday (Room C133)
 Juan TorresRincon (SBU)
 Nonequilibrium and transport coefficients in a new hadronic transport approach
Abstract: I will present some of my recent work in collaboration with the
SMASH (Simulating Many Accelerated StronglyInteracting Hadrons) group
at the Frankfurt Institute for Advanced Studies. SMASH is a hadronic
transport approach to simulate heavyion collisions, especially designed
for reactions at low and intermediate energies. However in
this talk I will discuss the performance of this code to numerically
reproduce an exact solution of the Boltzmann equation in an expanding
gas on a FriedmannRobertsonWalker spacetime and to describe the
decoupling process.
I will also give details of the extraction of the shear viscosity and the electric conductivity using
the GreenKubo formalism in connection with the theory of relativistic
hydrodynamic fluctuations. I will stress the important role of resonant
interactions in the determination of transport coefficients.

  June 11, 4h00PM Monday (Room C133)  Yingru Xu (Duke University)
 Heavy quark transport in heavyion collisions and Bayesian estimation of the transport coefficients
Abstract: At RHIC and the LHC, a deconfined QCD state of matter is created during
ultrarelativistic heavyion collisions. This stronglyinteracting hot
and dense matter  called QuarkGluon Plasma (QGP) exhibits
intriguing properties such as nearperfect fluid collectivity
and significant jet quenching. Heavy quarks are predominately produced
at the beginning of the collisions and their production can be
calculated by perturbative QCD due to their large masses. During their
propagation in the QGP medium, they lose energy while
interacting with the medium. At the end of the evolution, heavy quarks
hadronize into heavy flavor hadrons and continue the sequential hadronic
interactions. The large mass, the conservation of heavy flavor, and the
ability to interpret different momentum
region make heavy quark an ideal probe of the QGP medium.
In a transport approach, the interacting strength between heavy quarks
and the medium can be characterized by transport coefficients. In this
talk, we apply Bayesian inference to estimate the heavy quark transport
coefficient. The advantages of such modeltodata
comparison are: a systematic and rigorous handling of the experimental
and model uncertainties, a complete exploration of the model parameter
space, and the possibility to discover novel observables. In addition,
we compare two popular but different heavy
quark transport approaches, Langevin and linearized Boltzmann
equations, to better understand the modeling uncertainties.  Juan TorresRincon
  May 25, 1h00PM Friday (Room C133)
 Marco Catillo (University of Graz, Austria)
 On the emergence of particular symmetries
in QCD  Jacobus Verbaarschot
  May 15, 1h00PM Tuesday (Room C133)
 Vicente Vento (U. of Valencia, Spain)
 The Elusive Glueballs
Abstract: We review results in the physics of glueballs with the aim set on
phenomenology. In order to describe glueball properties we resort
to a variety of theoretical treatments which include lattice QCD, QCD sum rules,
constituent models and AdS/CFT models. We compare the theoretical
calculations with the PDG meson summaries to establish glueball candidates.
LHCb and future machines will play a crucial role in determining
their existence.  Ismail Zahed
  May 7, 1h00PM Monday (Room C133)  Stanislaw Glazek (University of Warsaw, Poland)  Collisions of gluon strings
Abstract: The ridge effect observed in high multiplicity events in
protonproton scattering at LHC can be due to the collisions
of flux tubes in the projectiles which are in turn related
to the fundamental physics of color confinement. We
discuss observable effects due to gluon string collisions in
electronproton and peripheral protonproton scattering
related to scattering of photons. The finalstate multiplicity
and elliptic flow are foreseen to exhibit variation due to
collisions of gluon strings at the level of several percent.  Ismail Zahed
  April 5, 4h00PM Thursday (Room C120)
 Ismail Zahed (Stony Brook U)
 Lowx from Strings at EIC
 Juan TorresRincon
 Special CFNS Seminar
 April 4, 1h00PM Wednesday (Room C133)
 ChangHwan Lee (Pusan National University, Korea)
 Tidal Deformability of Neutron Stars and Gravitational Waves
 Ismail Zahed
  Mar. 29, 1h00PM Thursday (Room C133)
 Yuya Tanizaki (BNL)  Exact results on massless 3flavor QCD and Z3QCD through new anomaly matching Abstract: Recently,
we find a new 't Hooft anomaly of massless 3flavor QCD, and it turns
out to be useful for constraining the possible chiral symmetry breaking
at finite density and zero temperature. We show that massless 3flavor
QCD has an 't Hooft anomaly related to the discrete axial symmetry. We
also discuss its consequences on Z(3)QCD, and especially show that one
of the center symmetry, the vector symmetry, or chiral symmetry must
always be broken spontaneously.  Juan TorresRincon   Mar. 26, 2h00PM Monday (Room C120)
 Ernst Sichtermann (LBNL)  gfactors and spin structure
Abstract: Spin,
an intrinsic form of angular momentum, plays important roles in nuclear
and elementary particle physics. A number of spin observables have
produced surprising results. In this talk, I will discuss
investigations and future opportunities with muon g2 and the spin
structure of the nucleon.   Special CFNS Seminar
 Mar. 9, 11h00AM Friday (Room C120)
 Xiangdong Ji (U. of Maryland)  Theoretical Challenges for EIC Physics  Ismail Zahed
 coorganized with CFNS
 Mar. 1, 10h30AM Thursday (Room D128)
 Yuxiang Zhao (INFN, Trieste, Italy)  Transverse spin structure study  from JLab, COMPASS to EIC
Abstract: To
understand the spin structure of a nucleon is a fundamental goal of
nuclear science. After half a century of investigations, our knowledge
of the nucleon spin structure has made impressive progress. However, our
current understanding is basically onedimensional. Meanwhile, the past
decade has witnessed tremendous experimental achievements, which led to
fascinating new insights into the 3D structure of the nucleon through
semiinclusive deep inelastic scattering processes (SIDIS). In this
talk, I will firstly give a brief introduction on perspectives for the
spin structure study to help people to get a feeling on where we are for
the onedimensional picture and why we need to move to 3D studies (TMDs
and GPDs). Then I will discuss the achievements and future efforts at
JLab (6 GeV and 12 GeV) and COMPASS (CERN) for the TMDs study. The
contributions from a future EIC on the study of TMDs will also be
discussed.  Dmitri Tsybyshev  Special CFNS Seminar
Talk broadcast by video conference at Room D128
 Feb. 26, 4h00PM Monday  Charlotte Van Hulse (U. of Basque Country, Spain)  Multidimensional photographs of the inner nucleon structure
Abstract: Deepinelastic scattering allows to study the threedimensional structure of the nucleon in momentum space and in mixed momentum and position space. Various experiments at Jefferson Lab, CERN and DESY have per formed measurements on semiinclusive deepinelastic scattering, providing access to the threedimensional parton distributions in momentum space, as well as on hard exclusive processes, sensitive to generalized parton distri butions and thus to the threedimensional nucleon structure in mixed mo mentum and position space. An overview of these measurements will be presented and discussed.  Dmitri Tsybyshev  Special CFNS Seminar  Feb. 22, 4h00PM Thursday  Jan Bernauer (MIT)  Proton puzzles at the precision frontier
Abstract: The nucleon and its structure are the focus of intense study on all energy scales, in both current and upcoming experiments. It is one of the simplest systems in nonperturbative QCD and the accurate description of its properties are a touchstone for theoretical calculations. However, many properties of the proton, for example mass and spin, are still puzzling. Recent precision experiments have highlighted two areas where we do not understand how nature works: the proton radius and the form factor ratio discrepancy. The former, still unsolved, may have opened the door to the discovery of physics beyond the Standard Model. While a solution for the latter seems in reach, the precision results of OLYMPUS prove theoretical calculations to be incomplete. In this talk, I will discuss the Mainz high precision form factor measurement and global form factor analysis, which are corner stones of the radius puzzle, and the results of the OLYMPUS experiment, set up to study the form factor ratio discrepancy. I will close with a short description of ongoing and future precisionfrontier experiments like MUSE and DarkLight.  Dmitri Tsybyshev  Special CFNS Seminar  Feb. 21, 1h00PM Wednesday  Enrico Rinaldi (BNL)  What lattice gauge theory can do for Dark Matter searches
Abstract: Lattice simulations of gauge theories are a powerful tool to investigate strongly interacting systems like Quantum ChromoDynamics (QCD). In recent years, the expertise gathered from lattice QCD studies has been used to explore new extensions of the Standard Model of particle physics that include strong dynamics. This change of gear in lattice field theories is related to the growing experimental search for new physics, from accelerator facilities like the Large Hadron Collider (LHC) to dark matter detectors like LUX or ADMX. In my presentation I will explore different plausible scenarios for dark matter physics where strong dynamics play a dominant role and can be tackled by numerical lattice simulations. The importance of lattice field theories is highlighted in the context of dark matter searches, both for direct detection experiments and for collider experiments.  Christos Kallidonis   Feb. 19, 4h00PM Monday  Christiano Fanelli (MIT)  Exotic physics both within and beyond the Standard Model at GlueX
Abstract: GlueX is a flagship nuclear physics experiment located at Jefferson Lab designed to understand the nature of confinement in QCD by mapping the spectrum of exotic mesons.The experiment utilizes the scattering on nucleon of 9 GeV linearly polarized photons derived from the recently upgraded CEBAF electron beam. The current status of the GlueX detector data collection will be discussed, with a brief overview of the first physics results. Taking advantage of the early data collected GlueX can also do a world’s leading search for BSM physics. In particular a compelling darkforce scenario introduces a new U(1)B gauge symmetry coupling to baryon number. A bump hunt strategy to search for a leptophobic boson has been extended to cover a wide unexplored region where all previous experiments could not set limits. The data collected at GlueX provided a significant contribution to this search.  Dmitri Tsybyshev  Special CFNS Seminar  Feb. 12, 1h00PM Monday  Mark Mace (SBU)  Multiparticle correlations and collectivity in proton nucleus collisions from the initial state
Abstract: In this talk, I will discuss recent progress in understanding multiparticle correlations in small systems from a simple initial state parton model. In this model of eikonal quarks scattering off of a dense nuclear target with localized domains of color charge, we are able to qualitatively reproduce many of the features observed in lightheavy ion collisions at RHIC and the LHC which are often ascribed to collective behavior. These include the ordering of nth moment two particle Fourier azimuthal anisotropy coefficient, vn{2}; a negative four particle second Fourier cumulant c2{4}, giving rise to a real v2{4}; the similarity for multiparticle second Fourier harmonics $v_2\{4\} \approx v_2\{6\} \approx v_2\{8\}\$; and the energy dependence of the four particle symmetric cumulants. While such patterns are often interpreted as signatures of collectivity arising from hydrodynamic flow, our results provide an alternative description of the multiparticle correlations seen in p+A collisions.  Christos Kallidonis   Feb. 1st. 4h00PM Thursday  Ciprian Gal (University of Virginia)  Understating the world with parity violation Abstract: The unique properties of the electroweak interaction give us the chance to deepen our understanding of the universe. Using parity violating electron scattering we can perform precision tests of the Standard Model or determine unknown nuclear properties. These types of measurements will guide future searches for physics beyond the standard model (BSM) and improve our knowledge of nuclear physics. In this seminar I will talk about the most recent result from this line of experiments. Qweak has made the most precise determination of the weak vector charge of the proton to date. The unprecedented precision in determining an electron scattering parity violating asymmetry has been used to extract the weak mixing angle at low energy. This low energy determination constrains possible BSM scenarios on levels comparable with direct searches from the LHC. I will conclude by presenting the exciting opportunities in parity violating electron scattering that will come in the next few years.  Dmitri Tsybyshev   Jan. 31st, 1h00PM Wednesday  Mohamed Anber (Lewis & Clark College)  Kstrings in pure YangMills theory via supersymmetry
Abstract: Studying kstrings in pure YangMills theory is a difficult task, thanks to the strong coupling nature of the problem. In this talk, I discuss a conjectured continuity between pure YangMills and N=1 super YangMills on R^3XS^1, which enables us to study and relate kstring in both theories. One can show, via reliable semiclassical analysis, that the Polyakovloop correlation functions depend only on the Nality of a representation, to the leading order. Further, I discuss Wbosons in super YangMills and show that they are deconfined on the string worldsheet, and therefore, can change neither the string Nality nor its tension. This phenomenon mirrors the fact that soft gluons do not screen probe charges with nonzero Nality in pure YangMills. I also comment on the scaling law of kstrings in super YangMills and compare our findings with strings in SeibergWitten theory and holographic studies that were performed in the 't Hooft largeN limit.  Edward Shuryak   Jan. 25, 4h00PM Thursday  Ronald Belmont (University of Colorado, Boulder)  Searching for collectivity and testing the limits of hydrodynamics: small systems at RHIC
Abstract: The standard picture of heavy ion collisions is that large systems (collisions of large nuclei like Au+Au and Pb+Pb) create a quarkgluon plasma that exhibits collective behavior indicative of nearly inviscid hydrodynamical evolution. Recently, data from small systems (collisions of a small projectile and a large target like d+Au and p+Pb) have been found to exhibit strikingly similar evidence for collective behavior. To further elucidate these results, RHIC has delivered a small system geometry scan of p+Au, d+Au, and 3He+Au collisions at 200 GeV between as well as a beam energy scan of d+Au collisions at 4 different energies: 200, 62.4, 39, and 19.6 GeV. In this talk we present results from the small systems scans at RHIC and discuss the implications for collectivity and the applicability of hydrodynamics.  Dmitri Tsybyshev   Jan. 22, 4h00PM Monday  Salvatore Fazio (BNL)  An uncharted territory  imaging the the building blocks of the visible matter in multidimensions
Abstract: Understanding the emergence of the nucleons from their constituents, the quarks and the gluons is a key challenge for modern science. During the past decade, there have been tremendous efforts towards going beyond the onedimensional structure of the proton to a threedimensional tomographic imaging of the proton’s constituents. This can shed light on the properties of these building blocks of the Universe, described by the theory of quantum chromodynamics (QCD). It also provides essential information to understand how the strong interaction keeps them confined in the fundamental particles. The 3D structure of the proton in coordinate and momentum space can be described respectively via the Generalized Parton Distributions (GPDs) and the Transverse Momentum Dependent (TMD) parton distribution functions. With advancements in theory and the development of phenomenological tools we are preparing for the next step in subnuclear tomographic imaging. The 2015 nuclear physics longrange plan endorsed the realization of a highluminosity polarized ElectronIon Collider (EIC) as the next large construction project in the United States. This will open a unique opportunity for very high precision measurements.
In this seminar I shall narrate my personal research experience in pursuing the multi dimensional knowledge of the proton’s structure and its spin. I will start with my investigation of GPDs at the ZEUS experiment at HERA, the previous and only electron+proton collider, through measurements of the exclusive production of a real photon – a process known as Deeply Virtual Compton Scattering. I will also tell how we are now accessing the Sivers TMD function in polarized proton+proton collisions at RHIC through the measurement of transverse single spin asymmetries in DrellYan and weak boson production. This is an effective path to test the fundamental QCD prediction of the nonuniversality of the Sivers function. Finally, I shall give a brief description of the EIC project, highlight several key high precision measurements from its planned broad physics program and discuss the expected impact on our current understanding of the 3D structure of nucleons and nuclei and on how the nuclear environment modifies the parton distributions.
 Dmitri Tsybyshev   Jan. 18, 4h00PM Thursday  Kiminad Mamo (SBU)  The Coulomb Branch of N=4 SYM and Its Gravity dual as a New Holographic Model to QCD
Abstract: We discuss various aspects of N = 4 super YangMills theory on the Coulomb branch (cSYM) and its string theory dual. After showing that N = 4 cSYM has most of the properties expected from pure YangMills theory at strong coupling, such as confinement (with Cornell potential), mass gap (with quantized mass spectrum), and an equation state similar to pure YangMills theory on the lattice, we will discuss the hydrodynamic transport coefficients, and hard probe parameters (such as drag coefficient and jet quenching parameter) of N = 4 cSYM plasma. In addition, a new holographic mechanism for hadronization or particle production from the QGP will be proposed, and shown to be equivalent to the wellknown CooperFrye formula in the hydrodynamic or low frequency limit. Finally, we add flavor to N = 4 cSYM by using coincident N_f D9anti D9 branes, and realize chiral symmetry breaking through open string tachyon condensation.  Christos Kallidonis   Jan. 31, 1h00PM Wednesday  Mohamed M. Anber (Lewis & Clark College)  Kstrings in pure YangMills theory via supersymmetry
Abstract: Studying kstrings in pure YangMills theory is a difficult task, thanks to the strong coupling nature of the problem. In this talk, I discuss a conjectured continuity between pure YangMills and N=1 super YangMills on R^3XS^1, which enables us to study and relate kstring in both theories. One can show, via reliable semiclassical analysis, that the Polyakovloop correlation functions depend only on the Nality of a representation, to the leading order. Further, I discuss Wbosons in super YangMills and show that they are deconfined on the string worldsheet, and therefore, can change neither the string Nality nor its tension. This phenomenon mirrors the fact that soft gluons do not screen probe charges with nonzero Nality in pure YangMills. I also comment on the scaling law of kstrings in super YangMills and compare our findings with strings in SeibergWitten theory and holographic studies that were performed in the 't Hooft largeN limit.  Eduard Shuryak   Jan. 11, 4h00PM Thursday  Christos Kalidonis (SBU)  Computing the nucleon spin from Lattice QCD
Abstract: The distribution of the proton spin amongst its constituent quarks and gluons is considered as one of the fundamental problems of physics, and a rich experimental and theoretical activity is ongoing, in the effort to resolve this longstanding puzzle. Nowadays, Lattice QCD is in a good position to provide reliable predictions and answers to fundamental problems, from first principles calculations. In this talk, we elaborate on the novel methodology employed in a recent Lattice QCD calculation with physical values of the parameters, in which the various quark and gluon contributions to the proton spin are determined to satisfactory accuracy. The calculation includes for the first time all contributions from sea quarks, which are notoriously difficult to obtain on the lattice. We show our final results of the quark and gluon contributions to the nucleon spin, with each contribution determined separately. We find very good agreement with the value 1/2 of the nucleon total angular momentum, thus resolving the long standing “proton spin puzzle".
   Nov 29, 1h00PM Wednesday  A. Gorsky (IITP, Moscow)  Tunneling in quantum mechanics and N=2 SUSY YangMills theory
Abstract: We discuss the Nekrasov partition function in $\mathcal{N}=2$ supersymmetric YangMills (SYM) gauge theory in the particular limit when one of the parameters of the $\Omega$deformation is large and focus at the nearnaive pole regions of the twisted superpotential. In the strict NekrasovShatashvili limit in $SU(2)$ case we explain at the gauge theory side the origin of the exponentially small gaps well above barrier in the spectrum of corresponding quantum mechanical(QM) problem. We show explicitly that the local 2d $\mathcal{N}=(2,2)$ models near the naive poles for $SU(2)$ case are the $\mathbb{C}P^1$ models with pole dependent values of K\"ahler parameters. The corresponding analysis for $SU(N)$ case is performed. Upon the proper resummation of the instanton transseries the poles become cuts enclosed with the curves of marginal stability around each cut. When the small second parameter of deformation is switched on the nearpole the twisted potential is identified with the vortex partition function in the sigma model. The interpretation of the nonperturbative phenomena in the classical Liouville conformal blocks is suggested and we argue that the classical conformal blocks enjoy the wallcrossing phenomena nearby the naive poles. We argue using the $AdS_3/CFT_2$ holography that upon the proper resummation of the nonleading terms the naive poles in the indermediate masses in the scattering of two heavy states in $AdS_3$ gravity get transformed into the cuts surrounding with CMS. Some comments concerning the possible interpretation of the gap in QM in terms of the Schwinger monopolepair production in 4d are presented.  D. Kharzeev   Nov 7, 1h00PM Tuesday  Adith Ramamurti  Role of QCD Monopoles in Jet Quenching
Abstract: QCD monopoles are magnetically charged quasiparticles whose BoseEinstein condensation (BEC) at T<T_c creates electric confinement and flux tubes. The ``magnetic scenario" of QCD proposes that scattering on the noncondensed component of the monopole ensemble at T>T_c is responsible for the unusual kinetic properties of QGP. In this talk, I will go over recent progress in this magnetic scenario, and focus on a calculation of the contribution of the monopoles to jet quenching phenomenon, using the BDMPS framework and hydrodynamic backgrounds. In the lowest order for cross sections, we calculate the nuclear modification factor, R_AA, and azimuthal anisotropy, v_2, of jets, as well as the dijet asymmetry, A_j, and compare those to the available data. We find relatively good agreement with experiment when using realistic hydrodynamic backgrounds. In addition, we find that eventbyevent fluctuations are not necessary to reproduce R_AA and v_2 data, but play a role in A_j. Since the monopoleinduced effects are maximal at T~T_c, we predict that their role should be significantly larger, relative to quarks and gluons, at lower RHIC energies.
 C. Kallidonis   Nov 6, 1h00PM Monday  Pak Hang Chris Lau (MIT)  Baryon constraint in SakaiSugimoto model
Abstract: SakaiSugimoto model is a topdown holographic qcd model. Baryons are described by instanton solutions in the model. The model has many successes such as the reproduction of chiral anomaly, computation of properties of baryons etc.. However, Hata and Murata pointed out and showed that one important baryon constraint which is responsible for selecting the correct 3flavour baryon multiplets cannot be derived from the model. In the talk, I will present our proposed solution and show how it can help recover the required constraint while preserving the other features in the hqcd model.  Ismail Zahed   Nov 1, 11h45AM Wednesday  James Lattimer (Stony Brook)  Constraints on Nucleosynthesis and Neutron Star Structure from the Neutron Star Merger GW170817
Abstract: The recent discovery of a neutron star merger GW170817 by LIGO/VIRGO dramatically confirms the hypothesis that the origin of heavy rprocess elements is decompressing neutron star matter tidally and shock ejected from mergers of compact binaries containing neutron stars. Initially considered speculative, and long contraindicated by observations and prevailing theories of galactic chemical evolution, this idea, which was proposed over 40 years ago, was revitalized in the last few years by the detection of Pu244 in ocean sediments, the observation of rprocess elements in stars in only one of ten ultrafaint dwarf galaxies, hints that some short gammaray bursts have infrared afterglows, the continued failure of supernova models to eject sufficient neutronrich matter, and a revolution in our understanding of galaxy formation. The predicted early blue (optical) and late red (infrared) emission observed from the visible counterpart of GW170817 essentially confirms rprocess nucleosynthesis in the ejecta in quantities sufficient to explain observed abundances. Moreover, coincident gammaray observations confirms the identification of mergers as a source of short gammaray bursts. In addition, the estimated masses of the inspiralling neutron stars, together with observations of significant mass ejection, establishes much better limits to the neutron star maximum mass (2.2 M_sun < M_max < 2.5 M_sun) then heretofore available. It has also been suggested that consistency with hydrodynamical models requires the radii of typical 1.5 M_sun neutron stars to be larger than about 10.6 km and the upper limit to tidal polarizability from the gravitational wave observation indicates radii smaller than 13.5 km, in line with neutron matter theoretical predictions.  Edward Shuryak  
(Postponed, new date will be posted)

Mark Mace (Stony Brook)

Multiparticle correlations and collectivity in proton nucleus collisions from the initial state
Abstract: In this talk, I will discuss recent progress in understanding multiparticle correlations in small systems from a simple initial state parton model. In this model of eikonal quarks scattering off of a dense nuclear target with localized domains of color charge, we are able to qualitatively reproduce many of the features observed in lightheavy ion collisions at RHIC and the LHC which are often ascribed to collective behavior. These include the ordering of nth moment two particle Fourier azimuthal anisotropy coefficient, vn{2}; a negative four particle second Fourier cumulant c2{4}, giving rise to a real v2{4}; the similarity for multiparticle second Fourier harmonics $v_2\{4\} \approx v_2\{6\} \approx v_2\{8\}\$; and the energy dependence of the four particle symmetric cumulants. While such patterns are often interpreted as signatures of collectivity arising from hydrodynamic flow, our results provide an alternative description of the multiparticle correlations seen in p+A collisions. 
Christos Kallidonis 

Oct 18th, 4h00PM
Wednesday 
Yuta Kikuchi (Stony Brook

Global inconsistency, 't~Hooft anomaly, and level crossing in quantum mechanics
Abstract: An 't Hooft anomaly is the obstruction for gauging symmetries, and it constrains possible lowenergy behaviors of quantum field theories by excluding trivial infrared theories. Global inconsistency condition is recently proposed as a milder condition but is expected to play an almost same role by comparing high symmetry points in the theory space. In order to clarify the consequence coming from this new condition, we discuss several quantum mechanical models with topological angles and explicitly compute their energy spectra. 
Christos Kallidonis 
 Oct 17th, 1h00PM Tuesday  Prof. Holger Bech Nielsen Niels Bohr Institute  The 3.5 keV Xray radiation from our Dark Matter Pearls  Christos Kallidonis   Oct 16th, 1h00PM Monday  Zohar Komargodski (Simons Center, Stony Brook)  Dynamics of Quantum Chromodynamics in 3+1 and 2+1 Dimensions
Abstract: We review recent developments concerning the dynamics of YangMills theory and QCD in 3+1 dimensions. In particular, we discuss the consequences of timereversal symmetry breaking, and show that this allows to make contact between the dynamics of fourdimensional theories and threedimensional theories. We describe new discrete anomalies in these systems and prove various general theorems about the possible ground states of YangMills theory in 3+1 and 2+1 dimensions. We present conjectures about new phases of 2+1 dimensional QCD and Adjoint QCD.  Edward Shuryak   Oct 5th, 4h00PM Thursday  Derek Teany (Stony Brook)  Transits of the QCD Critical Point  Christos Kallidonis   Oct 4th, 1h00PM Wednesday  Vlad Pantuev  Jet quenching and corona effect See this paper.  Edward Shuryak   Oct 3rd, 1h00PM Tuesday  Yizhuang Liu (Stony Brook)  Rotating Dirac Fermions in a magnetic field in 1+2, 3 dimensions  Ismail Zahed  
Sep 28th, 4h00PM
Thursday

Yizhuang Liu
(Stony Brook) 
Heavy baryons and their exotics from instantons in Holography 
Christos Kallidonis 

Past Seminars 
Time 
Speaker 
Title 
Host 
August 24, 3h30PM
Thursday

Stanislaw Glazek
(University of Warsaw & Yale University)

Quarkantiquark Hamiltonian in oneflavor QCD with a gluonmass ansatz
As a new tool for describing hadrons in the Minkowski spacetime,
the renormalization group procedure for effective particles (RGPEP)
is applied to heavy quarkonium problem in oneflavor QCD [1]. A
degree of universality is obtained for the binding quarkantiquark
interaction in the weakcoupling approximation, assuming that beyond
perturbation theory gluons obtain effective mass: the Coulomb potential
with BreitFermi spin couplings is corrected by a spinindependent
harmonic oscillator term that does not depend on the assumed effective
gluon mass or the choice of the RGPEP generator. The concept of
generator will be explained by comparison with Wilsonian renormalization
group procedure. The new tool is applicable in studies of the effective
gluon dynamics beyond the leading weakcoupling approximation or
entirely beyond the perturbative expansion.
[1] S.D.Glazek, M.GómezRocha,J .More, K.Serafin, arXiv:1705.07629
[hepph]

Ismail Zahed

August 1, 1PM
Tuesday

Rasmus Larsen
(Stony Brook)

Convergent perturbation theory in quantum mechanics
I will try to give some simple examples for why perturbation theory leads to oscillating factorial growing contributions. We will see that in the 1d integral this can be fixed by an integral cutoff. For 1d quantum mechanics the cutoff is effectively done by introducing an effective mass. With this, I will show how we can obtain the ground state energy of 1d quantum mechanics for the x^4 potential. In the x^4 case, the effective mass leads to an expansion in factors of m and g^(1/4). By minimizing the highest order contribution, we find that the ground state energy is proportional to g^(1/3) as it should be.


July 27, 3h30PM
Thursday

Sayantan Sharma
(BNL)

Insights on microscopic degrees of freedom of phases of QCD from Lattice
There has been a lot of progress in recent years on measuring the bulk thermodynamic properties of QCD from Lattice. However Lattice studies
can now give us new insights on even the microscopic degrees of freedom in different phases of QCD. I will discuss some instances like the
studies of fluctuations, screening masses and the eigenvalue spectrum of the Dirac operator.

J.F. Paquet

July 18, 1PM
Tuesday

Roy Lacey
(Stony Brook)



July 10, 3PM
Monday

Rasmus Larsen
(Stony Brook)

PhD Defence


June 1, 3h30PM
Thursday

Ismail Zahed
(Stony Brook/BNL)

Holographic string, saturation, entropy and black holes at collider energies


May 25, 3h30PM
Thursday

Dima Kharzeev
(Stony Brook/BNL)

Probing quantum entanglement at the Electron Ion Collider


May 4, 3h30PM
Thursday

Roy Lacey
(Stony Brook)

Charge separation measurements in p+Au and Au+Au collisions at RHIC; Implications for the search for the chiral magnetic effect


May 1, 12h45
Monday

Peng Huo
(Stony Brook)

Measurement of longitudinal flow correlations in Pb+Pb collisions at √sNN =2.76 and 5.02 TeV with the ATLAS detector


April 24, 1PM
Monday

Prithwish Tribedy
(BNL)

Search for the Chiral Magnetic Effect at RHIC : challenges and opportunities
In this talk I will discuss about the ongoing and future efforts at RHIC towards the search for the Chiral Magnetic Effect (CME). I will focus on the recent STAR measurements of the charge separation across the reaction plane, a predicted signal of the Chiral Magnetic Effect. Although charge separation has been observed, it has been argued that the measured separation in A+A collisions can be explained by elliptic flow related backgrounds. I will discuss on the challenges in disentangling such background contributions from the signals of CME. I will also discuss on implications of the recent measurements of charge separation in p+A collisions towards the search for CME.

J.F. Paquet 
April 20, 3h30PM
Thursday

Andrey Sadofyev
(MIT)

Chiral Vortical Effect for Bosons
The thermal contribution to the chiral vortical effect is believed to be related to the axial anomaly in external gravitational fields. We use the universality of the spingravity interaction to extend this idea to a wider set of phenomena. We consider the Kubo formula at weak coupling for the spin current of a vector field and derive a novel anomalous effect caused by the medium rotation: the chiral vortical effect for bosons. The effect consists in a spin current of vector bosons along the angular velocity of the medium. We argue that it has the same anomalous nature as in the fermionic case and show that this effect provides a mechanism for helicity transfer, from flow helicity to magnetic helicity.

Dima Kharzeev 
April 10, 1PM
Monday

Laura Tolos
(Institut de Ciencies de l’Espai)

Charm and Beauty @ Extremes
We study the behavior of excited charmed and beauty baryonic states within a unitarized coupledchannel theory in matter that fulfills heavyquark spin symmetry constraints. We analyze the implications for the formation of charmed mesic nuclei and the propagation of charmed and beauty hadrons in heavyion collisions from RHIC to FAIR energies.

J.F. Paquet 
April 6, 3h30PM
Thursday

Yuta Kikuchi
(Stony Brook)

Topological Properties of the Chiral Magnetic Effect in MultiWeyl Semimetals
I will discuss the chiral magnetic effect (CME) in multiWeyl semimetals (multiWSMs) based on the chiral kinetic theory. MultiWSMs are WSMs with multiple monopole charges that have nonlinear and anisotropic dispersion relations near Weyl points, and we need to extend conventional computation of CME in WSMs with linear dispersion relations. Topological properties of CME in multiWSMs are investigated in details for not only static magnetic fields but also timedependent (dynamic) ones. We propose an experimental setup to measure the multiple monopole charge via the topological nature hidden in the dynamic CME.


April 4, 2h30PM
Tuesday

Kong Tu
(Rice University)

New insights to the search for the anomalous chiral effects using small colliding system at the LHC
In relativistic heavy ion collisions, anomalous chiral effects have been predicted to occur in presence of a strong magnetic field induced by the spectator protons, e.g., the chiral magnetic effect (CME) and chiral magnetic wave (CMW). In the past decade, measurements of CME and CMW have been attempted from RHIC to the LHC energies, where significant signals were found to be in line with expectations of the chiral effects. However, soon after the initial excitement, various sources of background effects were identified and proposed to qualitatively describe the data. The origin of the backgrounds has been extensively studied, but still remains inconclusive to date. Recently, novel collective phenomenon has been found in highmultiplicity pA collisions, similar to those in AA collisions. Due to the weak correlation between the magnetic field direction and the event plane, the highmultiplicity pPb data are expected to have much suppressed CME and CMW signal, comparing to that in PbPb collisions, and thus provide an ideal testing ground to observables related to the anomalous chiral effects. In this talk, I will present new measurements related to the CME and CMW from CMS in pPb and PbPb collisions at the LHC, and discuss their implications to the search for the anomalous chiral effects including an outlook for future studies.


April 3, 12h45
Monday

Mingliang Zhou
(Stony Brook)

New results related to QGPlike effects in small systems with ATLAS
Quark Gluon Plasma (QGP), a new state of matter existing at high temperatures formed in relativistic heavy ion collisions, has been studied in measurements of various observables in Pb+Pb collisions at LHC. Recently, similar QGPlike effects have also been observed in small systems like $pp$ and $p+$Pb, by measuring twoparticle longrange azimuthal correlation. In order to access the collective nature of multiparticle production, the correlation measurements are extended using multiparticle cumulants, which have confirmed the collective behavior in $p+$Pb. However in $pp$, cumulants do not yet provide clear evidence for collectivity due to large residual dijet contribution. In order to address this, a new subevent cumulant method is applied, and it provides an evidence for collectivity in $pp$ collisions.


March 23, 1PM
Thursday

Carlos Naya
(Durham University)

A solitonic approach to neutron stars: The (BPS) Skyrme model
The Skyrme model is a low energy effective field theory of strong interactions where nuclei and baryons appear as collective excitations of pionic degrees of freedom. Proposed by Tony Skyrme in the sixties, his ideas received further support when it was discovered that in the limit of the large number of colours of QCD, an effective theory of mesons arises. In the last years, there has been a revival of Skyrme's ideas and new related models, some of them with BPS bounds (topological lower energy bounds), have been proposed. It is the aim of this talk to focus on the one known as BPS Skyrme model. After a brief introduction to this BPS limit we study its application to neutron stars where we will find that high maximal masses are supported. In addition, the BPS Skyrme model allow us to perform both meanfield and exact calculations and a comparison between both approaches will be presented.

J.F. Paquet 
March 13, 1PM
Monday

Ismail Zahed
(Stony Brook University)

SachdevYeeKitaev and equilibration


March 9, 3h30PM
Thursday

Mareike Haberichter
(University of Massachusetts  Amherst)

Nuclear Matter EoS and thermodynamic Properties of Skyrme models
The Skyrme model is a candidate to describe the low energy regime of QCD where baryons and nuclei are topological excitations in a lowenergy effective field theory of pions. The Skyrme model and its BPS variant (Skyrme model with a lower topological energy bound which is saturated) have been applied to the description of nuclei with notable recent success, e.g. quantitative description of Carbon12 (including the Holye state and its rotational band) and of the lowlying energy spectrum of Oxygen16. In this talk, we test Skyrme theories as models for nuclear matter at high densities and explore the thermodynamical properties of skyrmionic matter at zero temperature. We compute analytically the meanfield equation of state in the high and medium pressure regimes by applying topological bounds on compact domains. We identify which term in a generalised Skyrme model is responsible for which part in the equation of state and compare our findings with the corresponding results in the Walecka model. We find that the BPS submodel plays the dominant role at large densities. The BPS Skyrme model even allows us to derive thermodynamical variables and densities directly from the theory without having to perform a meanfield limit. This distinguishes the BPS Skyrme model from other models of nuclear matter where usually a meanfield limit has to be performed.

J.F. Paquet 
March 8, 4PM
Wednesday

Yachao Qian
(Stony Brook University)

PhD Defence


March 2, 3h30PM
Thursday

Sergey Syritsyn
(Stony Brook/BNL)

Lattice Calculation
of Nucleon Electric Dipole Moments
Searches for permanent electric dipole moments (EDM) of neutrons, protons, and nuclei are the most sensitive probes for CP violation, which is necessary for baryogenesis. Currently developed experiments will improve bounds on the neutron EDM by 23 orders of magnitude. However, to put constraints on CPviolating interactions, nonperturbative QCD calculations of nucleon structure are necessary. I will present some recent developments in lattice calculations of nucleon EDMs induced by quarkgluon CPodd interaction.


February 27, 1PM
Monday

Masaru Hongo
(RIKEN)

Pathintegral formula for local thermal equilibrium
Relativistic hydrodynamics is formulated based on the assumption that systems are almost in local thermal equilibrium. However, a quantum field theoretical way to handle such a locally thermalized system has not been clearly clarified. In this study, we develop a complete pathintegral formulation of relativistic quantum fields in local thermal equilibrium, which brings about the emergence of thermally induced curved spacetime. The obtained pathintegral formula for local thermal equilibrium enables us to derive nondissipative part of hydrodynamic constitutive relations based on symmetry arguments. As one application, we discuss a field theoretical derivation of anomalous hydrodynamics which captures the chiral magnetic/vortical effect.

Yuta Kikuchi 
February 23, 3h30PM
Thursday

Chun Shen
(Brookhaven National Lab)

A hybrid approach to relativistic heavyion collisions at the RHIC BES energies
Using a hybrid (viscous hydrodynamics + hadronic cascade) framework, we model eventbyevent bulk dynamics of relativistic heavyion collisions at the Relativistic Heavy Ion Collider (RHIC) Beam Energy Scan (BES) collision energies, including the effects from nonzero net baryon current and its dissipative diffusion during the evolution. This framework is in full (3+1)D, which allows us to study the nontrivial longitudinal structure and dynamics of the collision systems, for example the baryon stopping and transport, as well as longitudinal fluctuations. We study hadronic chemistry, identified particle spectra and anisotropic flow over the energy range relevant to the RHIC BES. We investigate the effects of netbaryon current/diffusion and preequilibrium dynamics on hadronic observables.

J.F. Paquet 
February 20, 1PM
Monday

Yuta Kikuchi
(Stony Brook)

Chiral magnetic effect without chirality source in asymmetric Weyl semimetals
We describe a new type of the Chiral Magnetic Effect (CME) in Weyl semimetals with an asymmetry in the dispersion relations of the left and righthanded chiral Weyl cones. In such materials, timedependent pumping of electrons from a nonchiral source generates a nonvanishing chiral chemical potential. This is due to the different capacities of the left and righthanded (LH and RH) chiral Weyl cones arising from the difference in the density of states in the LH and RH cones. The chiral chemical potential then generates, via the chiral anomaly, a current along the direction of an applied magnetic field even in the absence of an external electric field. We illustrate the effect by an effective field theory argument as well as by the chiral kinetic theory calculation for a Weyl semimetal with different Fermi velocities in the left and right chiral Weyl cones.


February 16, 2h30PM
Thursday

Juergen Eser
(Goethe University Frankfurt)

The extended linear sigma model within the functional renormalization group approach
We use the functional renormalization group (FRG) technique to explore the characteristics
of the socalled extended linear sigma model (eLSM). This model is an effective
description of the strong interaction in terms of quarks and mesonic fields. Besides scalars
and pseudoscalars, it also features vector and axialvector mesons.
The first part focuses on the restoration of chiral symmetry in the context of the transition
from hadronic matter to the quarkgluon plasma in the phase diagram of quantum
chromodynamics (QCD). Results on the order of the chiral phase transition in the presence
of vector and axialvector mesons will be presented. Vector mesons are of particular
interest since modifications related to chiral symmetry restoration affect their inmedium
spectral properties, which can be detected via decays into dileptons. Effects of the axial
anomaly and the explicit breaking of chiral symmetry due to nonzero quark masses are
also studied. The mass degeneracy of chiral partners beyond the phase boundary and the
phase diagram as a function of the temperature and the quarkchemical potential will be
shown.
The second part sheds light on the lowenergy limit of the eLSM. We consider the influence of wavefunction renormalization factors and couplings beyond the local potential
approximation. The infraredrelevant couplings can be associated with the corresponding
lowenergy constants of QCD.

J.F. Paquet 
February 3, 12PM
Friday

Adith Ramamurti
(Stony Brook University)

Practice talk: PathIntegral Monte Carlo Study of the Magnetic Component of QuarkGluon Plasma At and Above $T_c$


February 3, 12h40PM
Friday

Aleksas Mazeliauskas
(Stony Brook University)

Practice talk: Initial conditions for hydrodynamics from weakly coupled preequilibrium evolution


February 2, 3h30PM
Thursday

JeanFrançois Paquet
(Stony Brook University)

Practice talk: Electromagnetic probes in A+A and p+A collisions


February 2, 1PM
Thursday

Huiyoung Ryu
(Pusan National University)

Photoproduction and transition form factor

Ismail Zahed 
January 26, 3h30PM
Thursday

Björn Schenke
(Brookhaven National Lab)

The Ridge in p+p and p+Pb collisions: YangMills+Lund fragmentation
We present calculations of azimuthal anisotropies of produced gluons in p+p and p+Pb collisions within the YangMills framework.
In order to compare to recent experimental data from the LHC we combine the YangMills calculation with
the Lund fragmentation framework from PYTHIA, resulting in a new event generator that includes particle
production from the color glass condensate with string fragmentation. We present results of mean transverse
momentum and anisotropic flow for identified particles, showing a clear mass dependence, similar to that observed
in the experimental data.

J.F. Paquet 
January 26, 9h30AM
Thursday

Aleksas Mazeliauskas
(Stony Brook University)

PhD Defence: Fluctuactions in ultrarelativistic heavy ion collisions


January 18, 1PM
Wednesday

Peter Petreczky
(Brookhaven National Laboratory)

Weakly coupled QGP?

J.F. Paquet 
December 21, 3PM
Wednesday

Mauricio Adrian EscobarRuiz
(Universidad Nacional Autónoma de México & University of Minnesota)

Discussion on recent developments in semiclassical theories 
Edward Shuryak 
December 21, 1PM
Wednesday

Alezander Turbiner
(Universidad Nacional Autónoma de México & Stony Brook)

Developments in semiclassical theories 
Edward Shuryak 
December 8, 3h30PM
Thursday

Michał P. Heller
(Perimeter)

Hydrodynamization and transient modes of expanding plasma in kinetic theory

J.F. Paquet 
December 1, 3h30PM
Thursday

Stefan Flörchinger
(Heidelberg University)

Dissipation from the analytically continued 1 PI effective action
The analytic continuation from the Euclidean domain to real space of the oneparticle irreducible quantum effective action is discussed in the context of generalized local equilibrium states. Discontinuous terms associated with dissipative behavior are parametrized in terms of a conveniently defined sign operator. A generalized variational principle is then formulated, which allows to obtain causal and real dissipative equations of motion from the analytically continued quantum effective action. Differential equations derived from the implications of general covariance determine the spacetime evolution of the temperature and fluid velocity fields and allow for a discussion of entropy production including a local form of the second law of thermodynamics.

Aleksas Mazeliauskas 
November 28, 1PM
Monday

Morgan Henry Lynch
(University of Wisconsin  Milwaukee)

Applications of Accelerated Quantum Dynamics to Hadronic Physics
Utilizing the Unruh effect, and the associated temperature, I will present an effective Fermi theory of accelerationinduced interactions. This accelerated quantum dynamics provides a framework for computing a wide class of observables to probe the physics of high acceleration. General expressions for the emission rate, multiplicity, power, spectra, and displacement law of particles undergoing timedependent acceleration and transitioning into a final state of arbitrary particle number will be presented. As potential applications, I will show how this formalism may be applied to thermal particle production in hadronic collisions and quark gluon plasmas.


November 18, 12h45PM
Friday

Alina Czajka
(McGill University)

Quantumfieldtheoretical approach to shear and bulk relaxation times
The shear and the bulk relaxation times are important ingredients of the second order hydrodynamics whose success in heavy ion phenomenology is unquestioned. Unlike viscosites themselves, field theoretical calculations of the relaxation times are hard to come by in literature, especially for the bulk relaxation time. In this talk, we report two fieldtheoretical analyses involving the shear and the bulk relaxation time. First, by carefully examining the analytic structure of the stressenergy tensor response functions, we have been able to derive, for the first time, a Kubo formula involving both the shear and the bulk relaxation times. Second, by evaluating the Kubo formula within the massless scalar theory, we have so far been able to calculate the shear relaxation time in a simple form. We will then show how this calculation can be extended to calculate the bulk relaxation time as well.

J.F. Paquet 
November 10, 2h30PM
Thursday

Raju Venugopalan
(Brookhaven National Lab)

Berry's phase and the Chiral Anomaly from supersymmetric world lines: towards the anomalous Boedeker theory
We outline an ab initio derivation of how Berry's phase and the chiral anomaly arise in a heat kernel
regularization of the fermion determinant in QCD. We further argue that a semiclassical treatment of the resulting supersymmetric world line
equations of motion provides the framework to derive a chiral kinetic theory that includes the effects of fluctuations induced by topological transitions.
The phenomenological implications of these developments for the Chiral Magnetic Effect are noted.

Dima Kharzeev

November 9, 1PM
Wednesday

Yi Yin
(MIT)

New quantum effects in relativistic magnetohydrodynamics: topology, instability and selfsimilarity
Chiral anomaly induces a family of macroscopic quantum behaviors in chiral medium, including the chiral magnetic effect. The application of these effects covers systems of enormous varieties and scales, ranging from the structure of primordial magnetic field in the early universe to charged particle correlation in heavyion collisions and negative magnetoresistivity in the newly discovered Weyl semimetal. In this talk, I will present three closely related aspects of new quantum effects present in fluids that contain chiral fermions: topology, instability and selfsimilarity. I will demonstrate the magnetic reconnections changing chirality of magnetic flux induces in the fluid a quantized electric current, a new kind of the "chiral magnetic effect". I further show selfsimilar inverse cascade driven by the chiral magnetic current. Finally, I report a new type of instability in a magnetohydrodynamics due to anomaly.


November 2, 12h30PM
Wednesday

Yachao Qian
(Stony Brook)

Form Invariance, Topological Fluctuations and Mass Gap of YangMills Theory
We study the quantum YangMills theory in the presence of topologically nontrivial backgrounds. The topologically stable gauge fields are constrained by the form invariance condition and the topological properties. Obeying these constraints, the known classical solutions to the YangMills equation in the 3 and 4dimensional Euclidean spaces are recovered, and the other allowed configurations form the nontrivial topological fluctuations at quantum level. Together, they constitute the background configurations, upon which the quantum YangMills theory can be constructed. We demonstrate that the theory mimics the Higgs mechanism in a certain limit and develops a mass gap at semiclassical level on a flat space with finite size or on a sphere.

Ismail Zahed

October 27, 4PM
Thursday

Eugene Levin
(Tel Aviv University)

Perturbative QCD and beyond: BoseEinstein correlation and $v_n$ at any n

Dima Kharzeev

October 21, 12h45PM
Friday

Niklas Mueller
(Heidelberg University)

Chiral magnetic effect and anomalous transport from realtime lattice simulations
We present a firstprinciples study of anomaly induced transport phenomena by performing realtime lattice simulations with dynamical fermions coupled simultaneously to nonAbelian SU(Nc) and Abelian U(1) gauge fields. Investigating the behavior of vector and axial currents during a sphaleron transition in the presence of an external magnetic field, we demonstrate how the interplay of the chiral magnetic and chiral separation effect leads to the formation of a propagating wave. We further analyze the dependence of the magnitude of the induced vector current and the propagation of the wave on the amount of explicit chiral symmetry breaking due to finite quark masses. Further we perform simulations using overlapfermions for the first time in realtime, showing that in the classical statistical regime they can be related to the Wilson formulation.

J.F. Paquet 
October 6, 3h30PM
Thursday

Yuya Tanizaki
(Brookhaven National Lab)

Lefschetzthimble path integral for studying the Silver Blaze phenomenon
Recently, PicardLefschetz theory has received much attention in the context of the sign problem, because it enables us to study the system with the complex classical action nonperturbatively by extending the semiclassical analysis. In this seminar, after a brief introduction, I will apply it to the onesite Hubbard model. This model has a severe sign problem, which looks quite similar to that of the finitedensity QCD at low temperatures. By solving this model using the Lefschetzthimble path integral, we are trying to understand the structure of the sign problem of finitedensity QCD. In particular, I give a speculation about the earlyonset problem of the baryon number density, called the baryon Silver Blaze problem. We also discuss that the complex Langevin method does not work in a certain situation.

J.F. Paquet 
August 29, 2h30PM
Monday

Niko Jokela
(University of Helsinki)

Towards sliding stripes in holography
The D3D7' system provides a unique laboratory to address notoriously difficult questions in (2+1)dimensional fermionic systems at strong coupling via AdS/CFT. I will review select properties of the dense holographic matter in this brane intersection model. At low temperature, the ground state is a spatially modulated charge and spin density wave. A linear external electric field will kick the stripes to slide. Holographic techniques allows us to separate out the contributions of the modulation and the sliding to the electric conductivities. This provides a new viewpoint to understand the otherwise challenging quantum Hall fluids which spontaneously break the translational symmetry.

René Meyer 
August 8, 1PM
Monday

Tigran Kalaydzhyan
(University of Illinois at Chicago)

Testing gravity on accelerators
Weak equivalence principle (WEP) is one of the cornerstones of the
modern theories of gravity, stating that the trajectory of a freely
falling test body is independent of its internal structure and
composition. Even though WEP is known to be valid for the usual
matter, it has never been experimentally confirmed for antimatter and
relativistic matter. We make an attempt to constrain possible
deviations from WEP utilizing the modern accelerator technologies. We
analyze the (absence of) vacuum Cherenkov radiation, photon decay and
anomalous synchrotron losses at the Large ElectronPositron Collider
(LEP) and at Tevatron to put limits on a difference between the
gravitational and inertial masses of the relativistic
electrons/positrons. Our main result is the 0.1% upper limit on the
mentioned difference. I will further explain how this figure can be
improved with the analysis of a highenergy Compton scattering at the
future International Linear Collider (ILC).


August 4, 3h30PM
Thursday

J. Meng
(Peking University)

Covariant density functional theory for nuclear structure

Thomas Kuo 
July 27, 1PM
Wednesday

Michael Lublinsky
(BenGurion University)



July 15, 1PM
Friday

Song Shu
(Stony Brook)

One loop quantum fluctuations to the energy of the nontopological soliton in FriedbergLee model
I have used a practical method to calculate the oneloop quantum
correction to the energy of the nontopological soliton in
FriedbergLee model. The quantum effects which come from the
quarks of the Dirac sea scattering with the soliton bag are
calculated by a summation of the discrete and continuum energy
spectrum of the Dirac equation in the background field of soliton.
The phase shift of the continuum spectrum is numerically
calculated in an efficient way and all the divergences are removed
by the same renormalization procedure.


July 12, 1PM
Tuesday

Matti Järvinen
(École Normale Supérieure)

Magnetic field and theta dynamics in holographic QCD
I will start by an introduction to holographic QCD, concentrating on bottomup models where the backreaction of quarks to gluon dynamics is fully included (VQCD). I go on turning on a finite temperature and magnetic field, and demonstrate that inverse magnetic catalysis can be obtained. The physics of theta angle and axial anomaly can also be consistently included. In the limit of small quark mass, the predictions of the model agree with effective field theory: in particular the mass of the pions obey the GellMannOakesRenner relation and the etaprime meson obeys the WittenVeneziano relation.

René Meyer 
July 7, 12h30PM
Thursday

Rasmus Larsen



June 28, 1PM
Tuesday

Gabor Almasi
(GSI/BNL)

Fluctuations as probes of the chiral phase transition
Fluctuations of conserved charges are important observables that offer insight into the phase structure of strongly interacting matter. Around critical points, such as the chiral critical endpoint of QCD, higher order cumulants of the relevant quantities show universal behavior. The universal behavior of baryon number cumulants can be studied in effective models that lie in the same universality class as QCD. Such a model is for example the Quark Meson model. In my talk I discuss what one can learn from effective field theory studies of fluctuations and present my results obtained using the Functional Renormalization Group method in the Quark Meson model.

J.F. Paquet 
June 22, 1PM
Wednesday

Bin Wu
(Ohio State University)

Leading log resummation in highenergy parton production in QCD matter
In this talk I shall start with the double logarithmic correction to the transverse momentum broadening of highenergy parton in QCD matter. Such a double logarithmic term, averaged over the path length of the partons, can be taken as the radiative correction to the jet quenching parameter $\hat{q}$ and contributes to radiative energy loss. Then, I shall talk about how such a double log is hidden in the smallx evolution of a quarkantiquark dipole described by the BalitskyKovchegov equation in a large nucleus. At the end, I shall discuss that the smallx WW quark distribution includes such a medium double log as well as Sudakov double logs.

J.F. Paquet 
June 14, 1PM
Tuesday

Stefan Rechenberger
(Darmstadt/BNL)

The Functional Renormalization Group Method and Delayed Magnetic Catalysis
This talk will start with a very general introduction to the Functional Renormalization Group method, a powerful nonperturbative tool which can be applied to various problems. The second part of the talk will demonstrate this by discussing the influence of an external magnetic field on the chiral phase transition in the theory of strong interaction. The Functional Renormalization Group analysis shows that, driven by gluon dynamics, the chiral critical temperature decreases for small values of the magnetic field. For large values of the external field, however, the phase transition temperature increases.

J.F. Paquet 
June 6, 1PM
Monday

Yachao Qian
(Stony Brook University)

Form Invariance, Topological Fluctuations and Mass Gap of YangMills Theory

Ismail Zahed

June 3, 12h
Friday

Takumi Iritani
(Stony Brook University) 
Baryon interaction from lattice QCD
Baryon interactions are important quantities in nuclear physics. Both Luscher's finite volume method and HAL QCD method are used to calculate hadron interactions from lattice QCD. However, these two approaches give different results for nucleonnucleon system in the previous studies. For example, at unphysical pion mass, deuteron and dineutron become bound states in Luscher's method, while both channels are unbound in HAL QCD approach.
In this talk, I will clarify this puzzle, and show how to approach baryon interactions from lattice QCD correctly. I will also review recent progress of baryon potentials at physical pion mass from lattice QCD by HAL QCD Collaboration.


June 2, 3h30PM
Thursday

Sören Schlichting
(Brookhaven National Lab) 
Nonequilibrium dynamics of topological transitions and axial charges 
J.F. Paquet 
May 18, 12h
Wednesday

Aleksas Mazeliauskas
(Stony Brook)

Initial conditions for hydrodynamics from weakly coupled preequilibrium evolution
We use effective kinetic theory, accurate at weak coupling, to simulate
the preequilibrium evolution of transverse energy and flow perturbations in heavyion collisions. We provide
a Green function which propagates the initial perturbations to the energymomentum tensor at a time
when hydrodynamics becomes applicable. With this map,
the complete prethermal evolution from saturated nuclei to hydrodynamics can be modelled in a perturbatively controlled way.
[https://arxiv.org/abs/1605.04287]


May 16, 12h30
Monday

Heikki Mantysaari
(Brookhaven National Lab) 
Incoherent diffraction as a probe of proton structure fluctuations
Exclusive vector meson production can be used to directly probe the gluon density of a hadron. Measuring the cross section differentially in momentum transfer makes it possible to determine the transverse density profile (via coherent diffraction) and density fluctuations (incoherent diffraction) of the target hadron. This knowledge of the geometric fluctuations of the proton is particularly important for understanding collective phenomena observed in protonnucleus collisions.
We calculate coherent and incoherent diffractive vector meson production in photonproton scattering in the Color Glass Condensate framework. The dipole model used in the calculation is constrained by the proton structure function data. By implementing subnucleon scale fluctuations using the constituent quark model or the IPglasma framework we demonstrate that incoherent gammap scattering measurements from HERA suggest that the proton shape has large eventbyevent fluctuations.

J.F. Paquet 
April 28, 4PM
Thursday

Daniel Tapia Takaki
(University of Kansas) 
Nuclear gluon effects in gamma+Pb collisions at the LHC
By studying quarkonia photonuclear production, the ALICE and CMS collaborations have recently provided experimental evidence of nuclear gluon effects in gamma+Pb interactions at unprecedentedly low Bjorkenx values in the Pb nucleus. In this talk, an experimental and theoretical review about these studies will be given. The prospect of innovative quarkonia and jet measurements using the Run 2 data at the LHC will be described.

Abhay Deshpande 
April 28, 10AM
Thursday

Gökçe Başar
(University of Maryland)

Going with the flow: sign problem, Lefschetz thimbles and beyond
Monte Carlo methods, a robust way of studying field theories and many body systems, suffer from the sign problem when the action is complex. This includes an important set of problems such as most field theories, including QCD, and strong correlated electronic systems at finite density, as well as computation of real time quantities like transport coefficients. I will show that lifting the path integration to a complex manifold provides a way to ameliorate the sign problem, and introduce a new algorithm for carrying on such a computation. I will give some quantum mechanical examples with severe sign problems, including finite density of fermions and real time observables where Monte Carlo simulations can be profitably performed by this method. Finally I will discuss the 3+1d Bose gas with nonzero chemical potential.


April 27, 13h
Wednesday

Mauricio Adrian Ruis
(University of Minnesota)

Two charges in a magnetic field


April 22, 12h30
Friday

Rene Meyer
(Stony Brook)

Holographic YangMillsChernSimons Defects
ChernSimons gauge theories in 3 dimensions are an important class of quantum field theories, both because they (and their matter extensions) offer some of the few solvable QFTs in more than 2 dimensions, and because of their realworld applications in condensed matter theory.
In this talk we will discuss domain walls that shift the value of the ChernSimons level in field theories described in the IR by ChernSimonsYangMills theory, and their embedding in gauge/gravity correspondence in terms of D7 branes on the AdS soliton geometry. After carrying out holographic renormalization to evaluate the free energy with sources, we evaluate the behavior of correlation functions on and between defects, and from this derive interesting phase transitions as a function of defect separation and temperature. We will also comment on possible implications for the fractional quantum hall effect and a connection to 2d (holographic) QCD.


April 8, 12h30
Friday

Mark Mace
(Stony Brook/BNL)

Sphalerons Far From Equilibrium and Associated Phenomena
In this talk, I will present a first computation of sphalerons in the glasma; the highly occupied, weakly coupled gluon dominated preequilibrium matter created at early times after an ultrarelativistic heavy ion collisions. The sphaleron transition is a well known ingredient in the generation of anomalous vector current in a strong magnetic field, the socalled Chiral Magnetic Effect. We perform classicalstatistical realtime lattice simulations to study the dynamics of these topological transitions; simplifying our description by employing SU(2) gauge fields and neglecting the longitudinal expansion for this first study. I will show that the nonequilibrium sphaleron transition rate is time dependent and nonMarkovian, in addition to being dominant in comparison to the thermal equilibrium sphaleron transition rate. In addition, we can measure the scaling and separation of physical scales in analogy to those from thermal equilibrium, in order to parameterize this rate and understand the approach to equilibrium. I will then demonstrate that it is the magnetic screening length, which we extract nonpertrubatively, that controls this rate. Additionally, I will briefly mention studies of related anomalous transport effects that we plan on studying using this first principles classicalstatistical realtime lattice technology.


March 3, 3h30PM
Thursday

Yuta Kikuchi
(Stony Brook)

Mesoscopic dynamics of fermionic cold atoms: quantitative analysis of transport coefficients and relaxation times
We give a quantitative analysis of the shear viscosity, heat conductivity, and viscous relaxation times, using the novel microscopic expressions derived by the renormalization group (RG) method, where the Boltzmann equation is faithfully solved to extract the hydrodynamics without recourse to any ansatz. We examine the quantum statistical effects, temperature dependence, and scatteringlength dependence of the transport coefficients and the viscous relaxation times. The numerical calculation shows that the relation $\tau_\pi=\eta/P$, which is derived in the relaxationtime approximation (RTA) and is used in the most literature, turns out to be satisfied quite well, while the similar relation for the viscous relaxation time $\tau_J$ of the heat conductivity is satisfied only approximately with a considerable error.


February 18, 3h30PM
Thursday

Niklas Mueller
(BNL/Heidelberg)

Anomalyinduced dynamics in strong field QED
We investigate the impact of the AdlerBellJackiw axial anomaly on the realtime dynamics of quantum electrodynamics in the strong field regime.
While it is known that there is no net production of axial charges in equilibrium situations, we show that there are intriguing consequences if one considers the farfromequilibrium dynamics.
Using realtime lattice simulations we study the evolution of the electromagnetic field for initial conditions which lead to the production of vector and axial charges via the Schwinger effect and the axial anomaly.
We show that the Chiral Magnetic Effect, which has been predicted in the context of ultrarelativistic heavy ion collisions, can result in nontrivial experimental signatures, which could possibly be observed in future highintensity laser experiments.
Further I will give an outlook and first results on anomalous particle production in nonAbelian backgrounds as a first step towards the investigation of the Chiral Magnetic Effect using realtime lattice methods.

Dima Kharzeev 
February 12, 12h
Friday

Matthew Lippert
(Long Island University  Brooklyn) 
Phases of Holographic QCD
This talk will be a review of holographic QCD, focused primarily on the SakaiSugimoto model. I will explain the strengths and weaknesses of the SakaiSugimoto model, especially as compared with other holographic models, and I will present the results of the phase diagram at nonzero baryon charge.

Rene Meyer 
February 11, 3h30PM
Thursday

Takumi Iritani
(Stony Brook) 
Finite temperature phase transition of Nf = 3 SU(3) gauge theory with exact center symmetry
Confinement is often discussed in terms of center symmetry, however, quarks break this symmetry explicitly, and there are no definite order parameters for "confinement". In this talk, we introduce a formulation of center symmetric QCDlike theory with quarks by introducing specific boundary conditions. We discuss center and chiral phase transitions of such QCDlike theory at finite temperature from lattice QCD calculation.


January 29, 12h30PM
Friday

Yukinao Akamatsu
(Stony Brook) 
Kinetic regime of hydrodynamic fluctuation and renormalization 

January 15, 12h30PM
Friday 
Rasmus Larsen
(Stony Brook) 
Confinement and Chiral symmetry breaking from an Interacting Instantondyon ensemble for 2 colors and Nf flavors 

January 14, 4PM
Thursday

Ismail Zahed
(Stony Brook) 
Flow in spectra (part 2) 

January 11, 1PM
Monday

Ismail Zahed
(Stony Brook) 
Flow in spectra (part 1) 

January 8, 12h30PM
Friday

Edward Shuryak
(Stony Brook) 
New semiclassical method for QM and QFTs 

December 4 
Sergey Syritsyn 
TBA 
Robert Shrock 
December 2 
HueyWen Lin 
Frontiers in Lattice Nucleon Structure 
Robert Shrock 
November 30 
Yasumichi Aoki 
TBA 
Robert Shrock 
October 8, 4PM 
J. Noronha 
TBA 

October 9, 1PM 
Jacob Sonnenscheim 
TBA 

October 13, 1PM 
Jacob Sonnenschein 
TBA 

September 17, 4PM 
Yukinao Akamatsu 
Heavy Quarks in the QGP as Open Quantum
Sys

Edward Shuryak 
September 11, 1PM 
Song Shu 
Chiral Solitons 
Edward Shuryak 
September 3, 4PM 
Stanislaw Glazek 
Asymptotic Freedom of Gluons in the Fock Space 
Dima Kharzeev 

