{ital B}{sub {ital s}}-{ital {bar B}}{sub {ital s}} mixing, {ital CP} violation, and extraction of CKM phases from untagged {ital B}{sub {ital s}} data samples

Journal Article · Fri Sep 01 04:00:00 EDT 1995 · Physical Review, D

DOI:https://doi.org/10.1103/PhysRevD.52.3048· OSTI ID:122276

Dunietz, I ^[1]

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1. Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, Illinois 60510 (United States)

A width difference of the order of 20% has previously been predicted for the two mass eigenstates of the {ital B}{sub {ital s}} meson. The dominant contributor to the width difference is {ital b}{r_arrow}{ital c{bar c}s} transition, with final states common to both {ital B}{sub {ital s}} and {ital {bar B}}{sub {ital s}}. All current experimental analyses fit the time dependences of flavor-specific {ital B}{sub {ital s}} modes to a single exponential, which essentially determines the average {ital B}{sub {ital s}} lifetime. We stress that the same data sample allows even the measurement of the width difference. To see that, this article reviews the time-dependent formulas for tagged {ital B}{sub {ital s}} decays, which involve rapid oscillatory terms depending on {Delta} {ital mt}. In untagged data samples the rapid oscillatory terms cancel. Their time evolutions depend only on the much more slowly varying exponential falloffs. We discuss in detail the extraction of the two widths, and identify the large (small) {ital CP}-even (-odd) rate with that of the light (heavy) {ital B}{sub {ital s}} mass eigenstate. It is demonstrated that decay length distributions of some {ital untagged} {ital B}{sub {ital s}} modes, such as {rho}{sup 0}{ital K}{sub {ital S}},{omega}{ital K}{sub {ital S}},{ital D}{sub {ital s}}{sup (*){plus_minus}}{ital K}{sup (*){minus_plus}}, can be used to extract the notoriously difficult CKM unitarity triangle {gamma}. Sizable {ital CP}-violating effects may be seen with such {ital untagged} {ital B}{sub {ital s}} data samples. Listing {Delta}{Gamma} as an observable allows for additional important standard model constraints. Within the CKM model, the ratio {Delta}{Gamma}/{Delta}{ital m} involves no CKM parameters, only a hadronic uncertainty. Thus a measurement of {Delta}{Gamma}({Delta}{ital m}) would predict {Delta}{ital m}({Delta}{Gamma}), up to the uncertainty. (Abstract Truncated)

• Research Organization: Fermi National Accelerator Laboratory
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 122276
• Journal Information: Physical Review, D, Journal Name: Physical Review, D Journal Issue: 5 Vol. 52; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ANTI-B NEUTRAL MESONS
B MESONS
BRANCHING RATIO
CP INVARIANCE
EIGENSTATES
KOBAYASHI-MASKAWA MATRIX
MASS
MIXING
STANDARD MODEL
TIME DEPENDENCE
UNITARITY
VIOLATIONS
WIDTH