Distinguishing between hierarchical and lopsided SO(10) models

Journal Article · Sat Oct 01 04:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.72.075002· OSTI ID:20713664

Rastogi, Parul ^[1]

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1. Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)

A comparative study of two predictive SO(10) models, namely, the BPW model (proposed by Babu, Pati and Wilczek) and the AB model (proposed by Albright and Barr) is done based on their predictions regarding CP and flavor violations. There is a significant difference in the structure of the fermion mass matrices in the two models (which are hierarchical for the BPW case and lopsided for the AB model) which gives rise to different CP and flavor violating effects. We include both standard model (SM) and supersymmetric (SUSY) contributions to these processes. Assuming flavor universality of SUSY-breaking parameters at a messenger scale M* > or approx. M{sub GUT}, it has been shown that renormalization group based post-GUT (grand unified theory) physics gives rise to large CP and flavor violations. While these effects were calculated for the BPW model recently, this is the first time (to our knowledge) that post-GUT contributions have been included for the AB model. The values of {delta}m{sub K}, {epsilon}{sub K}, {delta}m{sub B{sub d}} and S(B{sub d}{yields}J/{psi}K{sub S}) are found, in both models, to be close to SM predictions, in good agreement with data. Both models predict that S(B{sub d}{yields}{phi}K{sub S}) should lie in the range +0.65-0.74, close to the SM prediction and that the electric dipole moment (EDM) of the neutron {approx_equal}(fewx10{sup -26})e-cm, which should be observed in upcoming experiments. The lepton sector brings out marked differences between the two models. It is found that Br({mu}{yields}e{gamma}) in the AB model is generically much larger than that in the BPW model, being consistent with the experimental limit only with a rather heavy SUSY spectrum with (m{sub o},m{sub 1/2}){approx}(1000,1000) GeV. The BPW model, on the other hand, is consistent with the SUSY spectrum being as light as (m{sub o},m{sub 1/2}){approx}(600,300) GeV. Another distinction arises in the prediction for the EDM of the electron. In the AB model d{sub e} should lie in the range 10{sup -27}-10{sup -28}e-cm, and should be observed by forthcoming experiments. The BPW model gives d{sub e} to be typically 100 times lower than that in the AB case. Thus the two models can be distinguished based on their predictions regarding CP and flavor violating processes, and can be tested in future experiments.

• OSTI ID: 20713664
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 7 Vol. 72; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
CP INVARIANCE
ELECTRIC DIPOLE MOMENTS
ELECTRONS
GEV RANGE
HADRONIC PARTICLE DECAY
MATRICES
MUONS
NEUTRONS
RENORMALIZATION
REST MASS
SO-10 GROUPS
STANDARD MODEL
SUPERSYMMETRY
SYMMETRY BREAKING