Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Measurement of B Hadron Masses in Exclusive J/psi Decays with the CDF Detector
Author: Measurement of B-hadron Masses at CDF Run II
Author: Andreas KornPublisher:
ISBN:
Category :
Languages : en
Pages : 266
Book Description
We measure the mass of b-hadrons in exclusive J/[psi]-decay modes. The correct momentum scale is established by the following steps: validate and quantify distortions or systematic effects in the Central Outer Tracker and Silicon Vertex Detector, apply and fine tune the energy loss corrections per track, and finally tune the magnetic field scale. With the momentum scale established, we find: m(B) = 5279.10 ± 0.41 (stat) ± 0.36 (sys), m(B0) = 5279.63 ± 0.53 (stat) ± 0.33 (sys), m(B[s]0) = 5366.01 ± 0.73 (stat) ± 0.33 (sys), m(A[b]) = 5619.7 ± 1.2 (stat) ± 1.2 (sys) MeV/c2. The measurements of the A[b] and B[s], masses are the current world best. The value of the A[b] mass is consistent with the CDF run I measurement resolving a discrepancy in the PDG average.
CP Violation in {B_s}^0 -> J/psi.phi Decays
Author: Sabato LeoPublisher: Springer
ISBN: 3319079298
Category : Science
Languages : en
Pages : 146
Book Description
This thesis reports on the final measurement of the flavor-mixing phase in decays of strange-bottom mesons (B_s) into J/psi and phi mesons performed in high-energy proton-antiproton collisions recorded by the Collider Experiment at Fermilab. Interference occurs between direct decays and decays following virtual particle-antiparticle transitions (B_s-antiB_s). The phase difference between transition amplitudes (“mixing phase”) is observable and extremely sensitive to contributions from non-standard-model particles or interactions that may be very hard to detect otherwise – a fact that makes the precise measurement of the B_s mixing phase one of the most important goals of particle physics. The results presented include a precise determination of the mixing phase and a suite of other important supplementary results. All measurements are among the most precise available from a single experiment and provide significantly improved constraints on the phenomenology of new particles and interactions.
Measurement of the Inclusive B-Lifetime Using $\rm {J/\psi}$'s at the CDF Experiment
Author: Measuring the B-Lifetime Using Inclusive Jpsi at Cdf
Author: Hans WenzelPublisher: LAP Lambert Academic Publishing
ISBN: 9783843367356
Category :
Languages : en
Pages : 136
Book Description
This dissertation describes the measurement of the average B hadron lifetime using a high statistics sample of B--> J/psi X decays produced in proton antiproton collisions at a center of mass energy of 1.8 TeV at the Fermilab Tevatron. The integrated luminosity of the sample is 10.1 pb-1 recorded with the Collider Detector at Fermilab (CDF). In this analysis the decay vertex of the decay J/psi -->mu^+ mu^-$ as reconstructed by a silicon vertex detector is used to extract the lifetime from the data. We find the following value for the average b hadron lifetime: [ tau_{B} = 1.46 pm 0.06; (stat.); pm 0.06; (syst.); ps] This is the first measurement of the b-hadron lifetime at a hadron collider. It demonstrates that it is possible to access the large b-quark production cross section in $poverline{p}$ collisions and to achieve high statistics even in modes which have small product branching ratios as in this case: $BR(Brightarrow J/psi X) cdot BR(J/psi rightarrow mu^+ mu^-) = 7.7 times 10^{-4}$.
Measurement of the $B \to J/\psi X$ Inclusive Cross-section at the Collider Detector at Fermilab
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The Collider Detector at Fermilab (CDF) is a multi-purpose detector designed to study proton-antiproton collisions at center-of-mass energies of 1.96 TeV/c2. One of the most importatn components of CDF is the silicon tracking detector. A detailed description of the testing and construction of the CDF silicon tracker is presented. Measurements of the tracking efficiency of the completed detector are also provided. Using 36 pb−1 of the J/[psi] data sample collected by CDF between February and October 2002, the inclusive B → J/[psi] X cross-section is measured in p{bar p} interactions at √s = 1.96 TeV/c2. The fraction of J/[psi] events arising from the decay of b hadrons is extracted using an unbinned maximum likelihood fit to the decay length of the J/[psi] candidates. The p{sub T} dependent differential cross section for inclusive B → J/[psi] X events with rapidity.
Measurement of $b$ Hadron Lifetimes in Exclusive Decays Containing a $J/\psi$ in $p-̂$ Pbar Collisions at $\sqrt{s}
Author: La Vallese
Author: B-physics Measurements at the Tevatron
Author: S. D'AuriaPublisher:
ISBN:
Category :
Languages : en
Pages : 8
Book Description
We present experimental results on b-hadron mass measurements and b-meson oscillations based on integrated luminosity of 250 to 450 pb{sup -1} of p{bar p} collisions at {radical}s = 1.98 TeV by the CDF and D0 collaborations at the TeVatron. The masses of b-hadrons have been measured precisely by the CDF collaboration in decays containing a J/{psi}. A blind search of the decay mode B{sub c} {yields} J/{psi}{pi}{sup +} resulted in a peak of 18.9 {+-} 5.4 candidates at a mass value of 6287.0 {+-} 4.5 {+-} 1.1 MeV/c{sup 2}. A new limit has been set to the decay B{sub d, s} {yields} {mu}{sup +}{mu}{sup -}. Both the CDF and D0 collaborations are in the position to put a limit on the frequency of the B{sub s} oscillations. D0 reports {Delta}m{sub s}> 5.0 ps{sup -1}.
Mass and Lifetime Measurements with Exclusive B Reconstruction at CDF.
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Lifetimes and masses of B mesons have been measured in exclusively reconstructed decays including J/[psi] [yields] [mu][sup +] decays. In 19.3 pb[sup [minus]1] of [bar p]p collisions at [radical]s = 1.8 TeV taken in 19920--93 at the Fermilab Tevatron collider, approximately 300 B mesons have been fully reconstructed. The measurements require precise determination of the helical track parameters of charged particle tracks. We find M(B[sub S][sup O]) = 5367.7 [plus-minus] 2.4 [plus-minus] 4.8 MeV/c[sup 2], [tau](B[sup +]) = 1.61 [plus-minus] 0.16 [plus-minus] 0.05 ps, and [tau](B[sup O]) = 1.57 [plus-minus] 0.18 [plus-minus] 0.08 ps.