WEAK INTERACTIONS IN THE STANDARD MODEL AND BEYOND
Academic year 2022/2023
Lecturers: R. Contino and M. Nardecchia
Pratical info
Emails:
Time schedule:
Monday 14-16, aula Rasetti
Wednesday 16-18, aula Rasetti
Friday, 14-15, aula Conversi
Office hours: any time but better to send an email or arrange with the teacher:
Google Classroom code: ewowi3i
Exam dates in 2023
Students who want to give the exam need to i) register on Infostud (registrations close a few days before the opening date) and ii) sign up on the excel file by writing their names in one of the available slots (links to excel files will be made available after registration on Infostud is closed.
Winter Session, 1st call [Infostud opening date: 24 January] - Exams date(s): 27 January, to book the exam use this link
Winter Session, 2nd call [Infostud opening date: 10 February] - Exams date(s): 13 and 24 February, to book the exam use this link
Spring Extra Session [Infostud opening date: 16 April ] - Exams date(s): 2,3 and 18 of May, to book the exam use this link
Summer Session, 1st call [Infostud opening date: 27 June] - Exams date(s): 29 June, to book the exam use this link
Summer Session, 2nd call [Infostud opening date: 12 July] - Exams date(s): 18 July, to book the exam use this link
Fall Session [Infostud opening date: ] - Exams date(s):
Fall Extra Session [Infostud opening date: 12 September] - Exams date(s):
Lectures
Lectures by prof. Nardecchia
23/09/2022 [1h]: Introduciton and discussion about the program of the course.
28/09/2022 [2h]: Dimensional analysis, relevant energy scales. Rules to construct models. How to count physical parameters. Quantum numbers of the SM fields. [GT]
30/09/2022 [1h]: Muon Decay in the SM. [Sa]
Lectures by prof. Contino
03/10/2022 [2h]: Review of the SM lagrangian: field content and quantum numbers, electroweak symmetry breaking.
05/10/2022 [2h]: Review of the SM lagrangian: renormalizable xi gauges and unitary gauge, masses and couplings in the unitary gauge (tree level). Parity.
Lectures by prof. Nardecchia
07/10/2022 [1h]: Charge conjugation [We1]
10/10/2022 [2h]: Discrete symmetries recap, phenomenological implications. [We1] e [BLS]
12/10/2022 [2h]: CP violation in the SM. [GT] e [BLS]
17/10/2022 [2h]: CKM matrix and its parametrizations. Unitarity Triangle. Absence of tree level FCNC in the SM. [GT]
19/10/2022 [2h]: Exmples of FV in beyond the SM. 2HDM and flavour violation in the Z couplings. [GT]
21/10/2022 [1h]: FCNC at one loop. GIM mechanism at the quark level. [GT]
24/10/2022 [2h]: Running coupling constant. Ratio R and RGE. See chapter 3 of Introduction to QCD by M. Mangano
26/10/2022 [2h]: Universality of renormalization of the electric charge. Exact and approximate symmetries of QCD. [ScSc]
28/10/2022 [1h]: Spontaneous symmetry breaking of the chiral symmetry, lightest pseudo-scalar octect and goldstone bosons. [ScSc]
2/11/2022 [2h]: Anomalies in quantum field theory [S] chapter 75
4/11/2022 [1h]: Anomalies in quantum field theory [S] chapter 76.
7/11/2022 [1h]: Global anomalies, phenomenological implications.
9/11/2022 [2h]: EFT general aspects. EFT for GB, Chiral lagrangian [P]
11/11/2022 [1h]: Chiral lagrangian, external currents.[P]. [26+4]
14/11/2022 [2h]: Charged pion decay, test of lepton flavour universality, PNGB masses. [P] e [ScSc].
16/11/2022 [2h]: Semileptonic decays of light hadrons. Charged pion and neutron beta decays, Vud [G] chapter 4. [Sa] lecture 32.
18/11/2022 [2h]: Semileptonic kaon decays, Vus. [G] chapter 4. [32+4]
Lectures by prof. Contino
21/11/2022 [2h]: Accidental symmetries of the SM: baryon and lepton numbers. Neutrino masses via the Weinberg operator or from a right-handed neutrino, see-saw mechanism. Hierarchy problem of the SM (quick introduction).
23/11/2022 [2h]: Fujikawa approach to anomalies; anomaly-free matter content: vectorlike and (pseudo)real representations; anomaly of baryon and lepton numbers, accidental symmetry of the SM; constraints on hypercharges from anomaly cancellation. [We2]
25/11/2022 [1h]: SU(5) Grand Unification Theory: field content, running of gauge couplings, doublet-triplet splitting problem. [CL chapter 14]
28/11/2022 [2h]: Accidental symmetry of the SU(5) GUT and its connection to B-L; proton decay and bound on MGUT. [CL chapter 14] Examples of anomaly-free new matter content: vectorlike fermions vs 4th generation; decoupling.
30/11/2022 [2h]: Custodial symmetry of the SM; pattern of global symmetry breaking in the SM. Non-linear electroweak Lagrangian: analogy and differences with the QCD chiral Lagrangian. [CoAT]
2/12/2022 [1h]: More on non-linear electroweak Lagrangian and custodial symmetry: Higgs couplings and comparison with linear Lagrangian. [CoAT]
5/12/2022 [2h]: Behavior of scattering amplitudes at high energy for generic Higgs couplings; perturbativity and renormalizability of the EW chiral Lagrangian in the space of couplings. [CoAT]
7/12/2022 [2h]: Overview of Higgs physics at the LHC: production modes, decay channels, fit to Higgs couplings, double Higgs production. [see slides] The Standard Model with v < LambdaQCD: EW symmetry breaking from the quark condensate.
12/12/2022 [2h]: The Standard Model with v < LambdaQCD: overall pattern of global symmetry breaking, QCD condensate and its alignment, W and Z masses from the QCD dynamics. Technicolor Theories. [QS], [CL] sec.13.1, [TC]
14/12/2022 [2h]: Electroweak Precision Tests of the SM: EW schemes, LEP1 and SLC experiments, observables at the Z pole, Improved Born Approximation and pseudo-observables.
16/12/2022 [1h]: Electroweak Precision Tests of the SM: more pseudo-observables, experimental results at the Z pole, lepton and quark universality.
19/12/2022 [2.5 h]: Observables at LEP2 and Tevatron. Theoretical calculation of EWPT: structure of 1-loop corrections; dependence of EW pseudo-observables on the Higgs and top mass, definition of the Altarelli-Barbieri espilon parameters; deviation from universality in the Zbb coupling. Results of the fit to EWPT.
21/12/2022 [2h]: Corrections to EWPO from heavy New Physics: parameters S,T,W,Y of Barbieri et al. and comparison with S,T,U of Peskin-Takeuchi; short-distance vs long-distance effects; dim-6 operators corresponding to S,T,W,Y; 1-loop effects and renormalization of dim-6 operators.
9/1/2023 [2h]: The concept of Naturalness as applied to predicted observables in a theory: Barbieri-Giudice criterion and 't Hooft criterion. Naturalness of the EW scale, a.k.a. the SM Hierarchy Problem: predictability of energy scales; naturalness of the QCD scale; unnaturalness of the EW scale, estimate of tuning using quadratically divergent corrections to the Higgs mass term. Previous applications of the Naturalness criterion: the GIM mechanism.
11/1/2023 [2h]: Previous applications of the Naturalness criterion: more on the GIM mechanism; electromagnetic correction to the pion mass [Das]. The Little Hierarchy Problem.
Lectures by prof. Nardecchia
12/1/2023 [2h, 9:30 aula Careri]: Neutral meson mixings and oscillations. CP violation. [Lecture notes by G. Ridolfi, see below]
13/1/2023 [2h]: Direct CP violation. K-K bar mixing in the Standard Model.
References
[CoAT] R. Contino, CERN Academic Training Lectures on Electroweak Symmetry Breaking
On Naturalness and the Hierarchy Problem
't Hooft "Naturalness, chiral symmetry and spontaneous chiral symmetry breaking" in Recent Developments in Gauge Theories, Cargese Lectures, 1979
Barbieri and Giudice, NPB 306 (1988) 63
Susskind PRD 20 (1979) 2619
Giudice and Rattazzi, GGI Tea Breaks Focus Meeting on "Naturalness and the future of High Energy Physics", link to video and slides
Barbieri, Strumia, hep-ph/0007265
For a recent fit to EWPO in the SMEFT framework, see: J. de Blas et al., PoS EPS-HEP2017 (2017) 467, arXiv:1710.05402
For recent bounds on stops and gluinos, see SUSY Summary Plots in ATL-PHYS-PUB-2022-013
On the GIM Mechanism
Glashow, Iliopoulos Maiani, PRD 2 (1970) 1285
Maiani, arXiv:1303.6154
see also: [Bu], [Si]
On Electroweak Precision Tests
LEP data and final results: hep-ex/0412015; hep-ex/0509008; arXiv:1012.2367
Precision Tests of the Standard Electroweak Model, P. Langacker editor (World Scientific)
Montagna, Nicrosini, Piccinini, hep-ph/9802302
Barbieri, Cargese Lectures
Matchev, TASI Lectures hep-ph/0402031
HepFit: Ciuchini et al. arXiv:1306.4644; De Blas et al. arXiv:1608.01509, arXiv:1116.05354
GFitter: Baak et al. arXiv:1107.0975
On the determination of delta(alfa)_had: Burkhardt and Pietrzyk arXiv:1106.2991
On Anomalous TGC: Hagiwara et al. NPB 282 (1987) 253; Gounaris et al. PRD 61 (2000) 073013
On epsilon parameters: Altarelli, Barbieri PLB 253 (1990) 161; Altarelli, Barbieri, Caravaglios NPB 405 (1993) 3
On S,T,W,Y: Barbieri et al. NPB 703 (2004) 127
From arXiv:
[Bu] A. Buras, arXiv:hep-ph/9806471
[Co] R. Contino, arXiv:1005.4269
[GT] Y. Grossmann, P. Tanedo, arXiv:1711.03624
[Man] A. Manohar, arXiv:1804.05683
[Ma] S. Martin, arXiv:hep-ph/9709356
[P] A. Pich, arXiv:hep-ph/9806303
[ScSc] S. Scherer, R. Schindler, arXiv:hep-ph/0505265
[Si] L. Silvestrini, arXiv:1905.00798
[Wi] S. Willenbrock, hep-ph/0410370
[Dr] H. K. Dreiner, H. E. Haber, S. P. Martin hep-ph/0812.1594
[QS] C. Quigg, R. Shrock, PRD 79 (2009) 096002, arXiv:0901.3958
[TC] L. Susskind, PRD 20 (1979) 2619, S. Weinberg, PRD 13 (1976) 974
[Das] Das et al., PRL 18 (1967) 759
Books:
[BLS] G. Branco, L. Lavoura, J. Silva, CP Violation
[CL] T.P. Cheng, L.F. Li, Gauge Theory of Elementary Particle
[DGH] J. Donoghue, E. Golowich, B. Holstein, Dynamics of the Standard Model
[Ge] H. Georgi, Weak Interactions
[MS] F. Mandl, G. Shaw, Quantum Field Theory
[PS] M. Peskin, D. Shroeder, An introduction to Quantum Field Theory
[Sc] M. Schwartz, Quantum Field theory and the Standard Model
[Sr] M. Srednicki, Quantum Field Theory
[We1] S. Weinberg, Quantum Field Theory , Volume 1
[We2] S. Weinberg, Quantum Field Theory , Volume 2
[GK] C. Giunti, C. W. Kim, Fundamentals of Neutrino Physics and Astrophysics
[RG] V. A. Rubakov, D. S . Gorbunov, Introduction to the Theory of the Early Universe (Hot Big Bang Theory)
[KT] E. W. Kolb, M. S. Turner, The Early Universe
Other lectures online:
Notes, slides, plots
Slides (powerpoint, pdf) on Higgs physics
Plots on EWPT
More Links: