Physics 752 (Prof. Agashe) – Spring 2022

 

Topics (and reading material) for term paper

                                                                                                  

You are to write (and present) sometime during finals week a term paper (at least 10 pages

long). The basic idea of this term paper is that you should explore some topic beyond what is

done in lecture, either an extension of the standard model (SM) itself (e.g., topics 1-4 listed

below) or some detail of SM that we didn't have time to cover (e.g, topic 6). And, you

should try to focus more on theory aspect of that topic than on the relevant

experimental issues, since that is the feature of this course.

 

I have listed some possible topics below, including suggestions for background reading material  (which can, at the least, serve as starting point for writing the paper - of course you should, if possible, explore further).

You should also feel free to suggest other topics - I can discuss them with you before I

approve of them for the term paper.

 

Finally, I leave it up to all of you to “divide-up” the topics among yourselves: it is even possible for two of you to collaborate on different parts of the same topic, e.g., supersymmetry and extra dimensions (see # 2 and 3 below) each have theory and phenomenology components.

(1) Theory of neutrino masses [including Dirac mass just like for charged fermions;

Majorana  mass from SU(2)_L triplet VEV or see-saw mechanism]: see section 13.2 of Cheng

and Li or a review here.

(2) Supersymmetry (SUSY): see here

In particular, this can be sub-divided into

(a) more formal/abstract topic of how to build a supersymmetric model/break SUSY as in

sections 3, 4 and 6 of above review and

(b) applying these general principles to build the minimal supersymmetric SM (MSSM) as in

section 5 , 7 (and possibly 8).

If you wish, some of you can form a "team" to cover this topic.

(3) Extra dimensions: see lecture notes here

In particular, the eventual goal of term paper (again, if you wish, two of you can work together

on this topic) could be to solve one (or more) of exercises in appendices of above lectures.

(More lecture notes on this topic are in references of above.)

(4) Grand Unified Theories: for general reviews, see here; "Grand Unified Theories and

Proton Decay" by P. Langacker, Phys. Rept. 72, 185 (1981), QC1.P6563 and "Grand Unified

Theories" by G. G. Ross, QC794.6.G7 R67 1985.

This can be sub-divided into

(a) based on SU(5) group: see chapter 14 of Cheng and Li.

(b) based on SO(10) group

(5) Direct detection of Dark Matter: for general reviews of (particle physics candidates for)

dark matter, see here and here.

For the term paper, I suggest understanding/re-doing part of the analysis of direct detection of

dark matter done here. For example, why a Majorana fermion gives spin-dependent cross-

section for scattering off of nuclei by exchanging a Z boson in t-channel: see analysis of

diagram 3a starting on page 13 vs. Dirac fermion which also gives spin-INdependent effect:

see analysis of diagram 2a on page 9 onwards.

 

(6) Phenomenology of CP violation [including connecting the theory calculation of 4-quark

flavor-violating operators to hadronic data]: see section XIV-3 to XIV-6 of Donoghue,

Golowich and Holstein for B-mesons and chapter IX for Kaons or section 12.2 of Cheng

and Li, mainly for Kaons.

(We will do some analysis of Fig. 12.5 in Cheng and Li - at quark level - in lecture.)

Also, see the reviews here and here.