Measurement of the strength of B0anti B0 oscillations with the ARGUS detector
Description
Using data collected with the ARGUS detector at the e+e- storage ring DORIS II at DESY, particle-antiparticle oscillations in the Bd0 system have been studied. Besides the standard method of tagging the b-flavor with fast leptons, a new technique has been introduced based on identifying the B-meson quark content with charged D*-mesons, thereby also separating neutral and charged B-decays. Combining the different methods applied, the strength of B0anti B0 oscillations, expressed in terms of the mixing parameter r, was found to be (19.1 ± 5.1 ± 4.4)%. Exploiting unitarity of the CKM matrix, this value leads to a lower limit on the top quark mass of mt > or approx. 55 GeV/c2. Using the upper bound on mt from neutral current data (mt < 190 GeV/c2) this analysis also constraints the CKM element vertical strokeVtdvertical stroke to be larger than vertical strokeVtdvertical stroke > 0.006. Furthermore this measurement predicts the strength of the yet unobserved Bs0 ↔ anti Bs0 transitions to lie in the range rs > or approx. 0.8. (orig.)
Availability note (English)
Available from FIZ Karlsruhe.Abstract (German)
Unter Verwendung der mit dem Detektor ARGUS am e+e--Speicherring DORIS II bei DESY aufgezeichneten Daten wurden Teilchen-Antiteilchen Oszillationen im System der Bd0-Mesonen untersucht. Neben der Standard Methode, den b-Flavor mit schnellen Leptonen zu taggen, wurde eine neue Technik entwickelt, die den B-Meson Quarkinhalt anhand geladener D*-Mesonen identifiziert, was gleichzeitig eine Separation neutraler und geladener B-Zerfaelle erlaubt. Das kombinierte Ergebnis fuer die Staerke der B0anti B0 Oszillatoren, ausgedrueckt durch den Mischungsparameter r, wurde zu (19.1 ± 5.1 ± 4.4)% gemessen. Unter Ausnutzung der Unitaritaet der CKM Matrix laesst sich aus diesem Wert eine untere Grenze fuer die Masse des top Quarks von mt > or approx. 55 GeV/c2 ermitteln. Zusammen mit der aus neutralen Strom-Prozessen resultierenden Einschraenkung von mt < 190 GeV/c2 kann aus dieser Analyse auch das CKM Element vertical strokeVtdvertical stroke auf Werte vertical strokeVtdvertical stroke > 0.006 eingegrenzt werden. Darueberhinaus schraenkt diese Messung die Staerke der bisher unbeobachteten Bs0 ↔ anti Bs0 Uebergaenge ein auf den Bereich rs > or approx. 0.8. (orig.)Additional details
Additional titles
- Original title (German)
- Messung der Staerke von B
Publishing Information
- Imprint Pagination
- 106 p.
- Report number
- DESY-F15--91-02
INIS
- Country of Publication
- Germany
- Country of Input or Organization
- Germany
- INIS RN
- 23003279
- Subject category
- S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
- Resource subtype / Literary indicator
- Numerical Data, Thesis, Non-conventional Literature
- Descriptors DEI
- ANNIHILATION; ANTI-B NEUTRAL MESONS; B NEUTRAL MESONS; CONFIGURATION MIXING; D NEUTRAL MESONS; D*-2010 MESONS; EFFECTIVE MASS; ELECTRON SPECTRA; ELECTRON-POSITRON INTERACTIONS; ELECTRONS; EXPERIMENTAL DATA; GEV RANGE 01-10; GEV RANGE 10-100; HADRONIC PARTICLE DECAY; KOBAYASHI-MASKAWA MATRIX; LIMITING VALUES; MASS SPECTRA; MATRIX ELEMENTS; MIXING RATIO; MUON PAIRS; MUONS MINUS; MUONS PLUS; PAIR PRODUCTION; PIONS PLUS; POSITRONS; QUARKS; REST MASS; SEMILEPTONIC DECAY; TOP PARTICLES
- Descriptors DEC
- ANTILEPTONS; ANTIMATTER; ANTIPARTICLES; B MESONS; BEAUTY PARTICLES; BOSONS; CHARM PARTICLES; CHARMED MESONS; D MESONS; DATA; DECAY; ELEMENTARY PARTICLES; ENERGY RANGE; FERMIONS; GEV RANGE; HADRONS; INFORMATION; INTERACTIONS; LEPTON-LEPTON INTERACTIONS; LEPTONS; MASS; MATRICES; MATTER; MESONS; MUONS; NUMERICAL DATA; PARTICLE DECAY; PARTICLE INTERACTIONS; PARTICLE PRODUCTION; PIONS; POSTULATED PARTICLES; PSEUDOSCALAR MESONS; SPECTRA; VECTOR MESONS; WEAK PARTICLE DECAY