We discuss how a possible violation of the combined symmetry CPT in the B meson system can be investigated at the LHC. We show how a tagged and an untagged analysis of the decay modes of both Bd and Bs mesons can lead not only to a possible detection of a CPT-violating new physics but also to an understanding of its precise nature. The implication of CPT violation to a large mixing phase in the Bs system is also discussed. © 2010 The American Physical Society.

ANIRBAN KUNDU

Physics

S NANDI

S K PATRA

Fulltext

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Physical Review D - Particles, Fields, Gravitation and Cosmology

We discuss some possible signals of CPT violation in the Bs system that may be probed at the Large Hadron Collider. We show how one can construct combinations of observables coming from tagged and untagged decay rates of Bs→Ds±K that can unambiguously differentiate between CPT violating and CPT conserving new physics models contributing in Bs0-B̄s0 mixing. We choose this particular mode as an illustrative example for two reasons: (i) In the Standard Model, there is only one decay amplitude, so it is easier to untangle any new physics; (ii) Bs being a neutral meson, it is possible to unambiguously identify any sign of CPT violation that occurs only in mixing but not in decay. We define an observable which is useful to extract the CPT violating parameter in Bs decay, and also discuss how far the results are applicable even if CPT violation is present in both mixing and decay. © 2013 American Physical Society.

Bsâ†’DsK as a probe of CPT violation

The T-odd triple-product (TP) asymmetries in B decays to a pair of vector mesons are treated as a good probe of CP violation because of the CPT symmetry. If CPT is no longer a good symmetry, such correlations between T-odd and CP-odd observables do not exist, and one might get unexpected nonzero TP asymmetries as a signal for CPT violation. We give a general formalism of TP asymmetries in the presence of CPT violation, either in decay or in neutral meson mixing. We also discuss how the observables depending on the transversity amplitudes are modified, and compare our expressions with the LHCb results, showing that the study of TP asymmetries might turn out to be one of the best probes for CPT violation. © 2013 American Physical Society.

CPT violation and triple-product correlations in B decays

Recently observed anomalies in the Bs→J/ψ decay and the like-sign dimuon asymmetry Aslb hint at possible new physics (NP) in the B s-B̄s mixing. We parameterize the NP with four model-independent quantities: the magnitudes and phases of the dispersive part M12 and the absorptive part Γ12 of the NP contribution to the effective Hamiltonian. We constrain these parameters using the four observables ΔMs, ΔΓs, the mixing phase βsJ/ψ, and Aslb. Our quantitative fit indicates that the NP should contribute a significant dispersive as well as absorptive part. In fact, models that do not contribute a new absorptive part are disfavored at more than 99% confidence level. We extend this formalism to include CPT violation, and show that CPT violation by itself, or even in presence of CPT-conserving new physics without an absorptive part, helps only marginally in the simultaneous resolution of these anomalies. The NP absorptive contribution to B s-B̄s mixing therefore seems to be essential, and would imply a large branching fraction for channels like Bs→ τ+τ-. © 2011 American Physical Society.

Reconciling anomalous measurements in Bs-BÌ„s mixing: The role of CPT-conserving and CPT-violating new physics

We investigate new physics models that can increase the lifetime differences in the Bq-B̄q systems (q=d, s) above their standard model values. If both Bq as well as B̄q can decay to a final state through flavor dependent new physics interactions, the so-called Grossman bound may be evaded. As examples, we consider the scalar leptoquark model and λ′′ -type R-parity violating supersymmetry. We find that models with a scalar leptoquark can enhance ΔΓs/Γs all the way up to its experimental upper bound and ΔΓd/Γd to as much as ∼2.5%, at the same time allowing the CP violating phase βs to vary between -45° and 20°. R-parity violating supersymmetry models cannot enhance the lifetime differences significantly, but can enhance the value of βs up to ∼±20°. This may bring the values of ΔΓq/Γq as well as βs within the measurement capabilities of B factories and the B physics experiment at the Large Hadron Collider (LHCb). We also obtain bounds on combinations of these new physics couplings, and predict enhanced branching ratios of Bs/d→τ+τ-. © 2007 The American Physical Society.

Journal	Physical Review D - Particles, Fields, Gravitation and Cosmology
Publisher	AMER PHYSICAL SOC
ISSN	1550-7998
Open Access	No