Sunghoon Jung    (정성훈) 

     Department of Physics and Astronomy, Center for Theoretical Physics,
     Seoul National University

     sunghoonj at snu.ac.kr ,   nejsh21 at gmail.com

I work on theoretical particle physics phenomenology, primarily on the ways to probe and understand the fundamental Nature beyond the Standard Model, from collider experiments, gravitational-wave observations, dark-matter detections, and cosmological probes.


Research Interests and Highlights:
My publications can be found at INSPIRES-HEP ("ea jung, sunghoon") and Google Scholar.   (Authors are in an alphabetical order.)

         
 Gravitational-Wave Fringe allows seeing dark matter.      Resonance Dip is another appearance of Higgs bosons.

1. Higgs phenomenology:  What physics lies beyond the Higgs boson? Anything that makes the Higgs work in the way observed will be many steps closer to the EARLY UNIVERSE.

  - Higgs precision study is the next step in digging out hints of the Early Universe.   -- We have been developing a
model-independent theoretical framework for the precision Higgs analysis.
  - 'Resonance dips' are new but generic appearances of heavy Higgs particles.   -- We have been developing a theoretical framework to describe them and exploring their exciting phenomenology.
  - The Higgs and the Higgsino are necessarily intimate particles.   -- We have discovered novel relations between those particles, which can help discover SUSY and resolve the LHC Inverse problem.
  - The Higgs-portal is an inevitable renormalizable interaction.   -- We studied the Abelian Higgs sector with the Higgs-portal and kinetic mixing, as a simple portal to the dark sector.
  - Can the Higgs potential be initially flat (hence, non-existent) at the Planck scale?   -- The scale invariance with U(1)B-L shows an exciting possibility.  
2. Gravitational Wave era:  What can we SEE with the GW? WHAT and HOW can we learn about particle physics frontiers and the Early Universe? 

  - 'GW Fringe' makes it possible to see the Universe.   -- We have been developing this new fantastic gravitational-lensing observable to probe dark matter and structures of the Universe.
  - LIGO + mid-frequency band has a great physics potential for probing dark matter of the Universe.   -- We have been exploring its various potentials and implications.
  - Surprisingly, the Doppler effect is not fully appreciated and utilized in the GW observation.   -- We pointed out that it can maximize our ability to localize the GW, which is possible in the LIGO + mid-band.
  - More exciting ideas are coming up soon.

3. Dark Matter mysteries:  What is it? Where is it? We need NEW possibilities and new ways to look for it.

  - GW Fringe is a new way to probe compact dark matter (such as primordial black holes, dark stars, axion mini-clusters) and cosmic strings.
  - GWs from binary mergers are inherently and exquisitely sensitive to light scalar dark matter (such as fuzzy or axion-like), coherently oscillating in the background of binary mergers.
  - Very Degenerate Higgsino Dark Matter can lead to unusual annihilation signals, induced by Sommerfeld-Ramsauer-Tounsend effects.

4. Supersymmetry at (future) colliders:  Is SUSY dead? What does the absence of discovery at the LHC imply for experimental and theoretical directions? Any 'future SUSY' will be qualitatively DIFFERENT from old SUSY that we have been looking for.

  - Prospects for Electroweakino and Gluino Discovery at a 100 TeV Hadron Collider:
  - Higgs and Higgsino signals in future SUSY:
  - Can SUSY be discovered through resonances?   --  Stoponium signals.
  - Displaced signals are ubiquitous from the Higgsino, Axino, Gravitino, and very light charginos

5. Top quarks:  Why is only the top quark so heavy, as heavy as the electroweak scale? It necessarily participates in the electroweak symmetry breaking. How and why?

  - Top-pair four-Fermi operators lead to various observables and physic insights from Renormalization Group Evolution. Can you believe RGE can teach us about top Afb?
  - Correlation of Top Asymmetries: Loop Versus Tree Origins   --  We can distinguish different origins.
  - Top Quark Forward-Backward Asymmetry from New t-channel Physics   --  awkward, but awesome.
  - Randall-Sundrum model likes the top quark   --  predilection of top quarks in RS models.



Lecture Notes:

- Higgs resonance dip and nothingness:  formalism and phenomenology
- Gravitational lensing:  formalism and application to gravitational wave

- Higgs mechanism:  (1) Landau-Ginzberg and Higgs, (2) Scaling and criticality, (3) Phase transition phenomena
- MadGraph:  basic usage



Group Activities:

- SNU CTP/NAPP Seminars.  (Regularly on Thursday 4pm at 56-521. If you are interested, please let me know. Anyone is welcome to attend.)
- SNU particle physics group Journal Club.
SnailLectures.  (SNU, Kunkuk, Yonsei, ChungAng  regularly gather and enjoy particle physics in the weekend afternoons. Lectures are generally aimed at graduate students.)

2018
- KIAS Winter Camp on Particle Physics.  (for undergrads. Dec. 26-29, 2018 @ Bloombista)
- Lecture series by Prof. James D. Wells - "Naturalness".  (Dec. 10-12, 2018 @ 56-521. Both theorists and expts, grads and undergrads are all welcome to join.)
- Lecture series by Prof. Kiwoon Choi - "Axions".   (Mar~Apr, 2018)
- Lectures by Prof. Eung Jin Chun on "Leptogenesis" and Chang Sub Shin on "Inflation".   (Apr, May, 2018)

2017
- "Higgs Mini-Workshop: Precision, BSM and Cosmology"  (Prof. Michael Peskin (SLAC, Stanford) and Junping Tian (Univ. of Tokyo) are our special guests.) 
KIAS Winter Camp on Particle Physics.  (for undergrads. Dec. 26-29, 2017 @ Bloombista)



Course Teaching:

- Quantum Field Theory 1 (19 Spring) :  Peskin&Schroder, Schwartz
- Particle Physics (18 Fall) :  Peskin new book
- Particle Physics in the Early Universe (18 Spring) :  Kolb and Turner 
- Modern Particle Physics Phenomenology (17 Fall) :  Electroweak precision, Higgs, QCD and Collider, Vacuum structures of Gauge theories



Mini CV:

- 2017 : Assistant Professor at Seoul National University.
- 2015 : Research Associate at SLAC, Stanford University. 
- 2012 : Research Fellow at KIAS. (alternative to military service duty as well)
- 2011 : Postdoc Researcher at University of Chicago, Enrico Fermi Institute. 
- 2011 : Ph.D at University of Michigan, Ann Arbor, under the supervision of James D. Wells.
- 2006 : BS in physics at Postech.



Awards and Honors:

- TJ Park (POSCO) Science Fellowship (2018-19) as a junior faculty
- Samsung Scholarship (2006-2010) as a Ph.D student