RUI: Theoretical Investigation of CP Violation in Extensions of the Standard Model

Taylor University, Upland IN

Investigators

Abstract

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." One of the strongest emphases in particle physics today is on searching for signals of "new physics", that is, physics beyond the Standard Model (SM). The next few years could witness important discoveries as the Large Hadron Collider (LHC) experimentalists map out physics at the TeV scale. Complementary searches for new physics (NP) are also underway at low energies, using indirect probes. Results from neutrino physics have already provided exciting hints regarding the structure of physics beyond the SM. Future neutrino experiments will continue to map out the masses, mixings and CP properties of neutrinos and to probe their essential nature (i.e., Majorana or Dirac). On another front, LHCb is expected to build on the precision B meson measurements made at Babar and Belle; a possible Super Flavor Factory could extend this reach, and would also make important contributions to tau and charm studies. Several of the low- and high-energy experiments are expected to employ CP-odd observables in the search for NP, since many extensions of the SM contain novel sources of CP violation. CP-odd observables can be useful discriminators between NP and SM effects; furthermore, such observables could help discern the structure of NP. The Principal Investigator will assess phenomenological effects of several extensions of the SM, concentrating on observables that are odd under CP. A complementary focus of the proposed work is expected to be the constraint, modification or generalization of various extensions of the SM. The proposed work will include emphases on both low- and high-energy processes. In the former case, the effects of new particles will be sought. In the latter, studies will be performed assuming that new particles could be produced on-shell in a collider environment. Specific projects include the calculation of rate asymmetries in chargino, stau and sbottom decays within supersymmetry, as well as investigations of top quark decays and certain B decays to vector-vector final states. Some of the broader impacts are that the proposed work will be useful to experimentalists as they begin to sift through large amounts of data searching for signals of NP. The direct involvement of several undergraduate students in the research will enhance the educational experiences of those students and will better prepare them for entrance into top graduate schools. The increased level of undergraduate research will also help the institution attract highly qualified undergraduate students to the physics program and will be particularly helpful in attracting more female and minority students, who are currently underrepresented in the physics program at Taylor.