| 1. |
- Abazov, M, et al.
(författare)
-
Direct Measurement of the Mass Difference between Top and Antitop Quarks
- 2009
-
Ingår i: Physical Review Letters. - 0031-9007. ; 103:13, s. 132001
-
Tidskriftsartikel (refereegranskat)abstract
- We present a measurement of the mass difference between t and (t) over bar quarks in lepton + jets final states of t (t) over bar events in 1 fb(-1) of data collected with the D0 detector from Fermilab Tevatron Collider p (p) over bar collisions at root s = 1.96 TeV. The measured mass difference of 3.8 +/- 3.7 GeV is consistent with the equality of t and (t) over bar masses. This is the first direct measurement of a mass difference between a quark and its antiquark partner.
|
|
| 2. |
- Abazov, M, et al.
(författare)
-
Measurement of B-s(0) Mixing Parameters from the Flavor-Tagged Decay B-s(0)-> J/psi phi
- 2008
-
Ingår i: Physical Review Letters. - 0031-9007. ; 101:24, s. 241801
-
Tidskriftsartikel (refereegranskat)abstract
- From an analysis of the flavor-tagged decay B-s(0)-> J/psi phi we obtain the width difference between the B-s(0) light and heavy mass eigenstates, Delta Gamma(s)=0.19 +/- 0.07(stat)(-0.01)(+0.02)(syst) ps(-1), and the CP-violating phase, phi(s)=-0.57(-0.30)(+0.24)(stat)(-0.02)(+0.08)(syst). The allowed 90% CL intervals of Delta Gamma(s) and phi(s) are 0.06
|
|
| 3. |
- Abazov, M, et al.
(författare)
-
Measurement of the WW Production Cross Section with Dilepton Final States in pp Collisions at s=1.96 TeV and Limits on Anomalous Trilinear Gauge Couplings
- 2009
-
Ingår i: Physical Review Letters. - 0031-9007. ; 103:19, s. 191801
-
Tidskriftsartikel (refereegranskat)abstract
- We provide the most precise measurement of the WW production cross section in pp collisions to date at a center of mass energy of 1.96 TeV, and set limits on the associated trilinear gauge couplings. The WW -> l nu l(')nu (l, l(')=e, mu) decay channels are analyzed in 1 fb(-1) of data collected by the D0 detector at the Fermilab Tevatron Collider. The measured cross section is sigma(pp -> WW)=11.5 +/- 2.1(stat+syst)+/- 0.7(lumi) pb. One- and two-dimensional 95% C.L. limits on trilinear gauge couplings are provided.
|
|
| 4. |
- Abazov, M, et al.
(författare)
-
Relative rates of B meson decays into psi(2S) and J/psi mesons
- 2009
-
Ingår i: Physical Review D. - 1550-7998. ; 79:11, s. 111102
-
Tidskriftsartikel (refereegranskat)abstract
- We report on a study of the relative rates of B meson decays into psi(2S) and J/psi mesons using 1.3 fb(-1) of p (p) over bar collisions at root s = 1.96 TeV recorded by the D0 detector operating at the Fermilab Tevatron Collider. We observe the channels B-s(0) -> psi(2S)phi, B-s(0) -> J/psi phi, B-+/- -> psi(2S)K-+/-, and B-+/- -> J/psi K-+/- and we measure the relative branching fractions for these channels to be B(B-s(0) -> psi(2S)phi)/B(B-s(0) -> J/psi phi)=0.53 +/- 0.10(stat)+/- 0.07(syst)+/- 0.06(B), B(B+ -> psi(2S)K+)/B(B+ -> J/psi K+)=0.63 +/- 0.05(stat)+/- 0.03(syst)+/- 0.07(B), where the final error corresponds to the uncertainty in the J/psi and psi(2S) branching ratio into two muons.
|
|
| 5. |
- Abazov, M, et al.
(författare)
-
Search for associated production of charginos and neutralinos in the trilepton final state using 2.3 fb(-1) of data
- 2009
-
Ingår i: Physics Letters B. - 0370-2693. ; 680:1, s. 34-43
-
Tidskriftsartikel (refereegranskat)abstract
- We report the results of a search for associated production of charginos and neutralinos using a data set corresponding to an integrated luminosity of 2.3 fb(-1) collected with the Demptyset experiment during Run II of the Tevatron proton-antiproton collider. Final states containing three charged leptons and missing transverse energy are probed for a signal from supersymmetry with four dedicated trilepton event selections. No evidence for a signal is observed, and we set limits on the product of production cross section and leptonic branching fraction. Within minimal supergravity, these limits translate into bounds on m(0) and m(1/2) that are well beyond existing limits.
|
|
| 6. |
- Abazov, M, et al.
(författare)
-
Search for Dark Photons from Supersymmetric Hidden Valleys
- 2009
-
Ingår i: Physical Review Letters. - 0031-9007. ; 103:8, s. 081802
-
Tidskriftsartikel (refereegranskat)abstract
- We search for a new light gauge boson, a dark photon, with the D0 experiment. In the model we consider, supersymmetric partners are pair produced and cascade to the lightest neutralinos that can decay into the hidden sector state plus either a photon or a dark photon. The dark photon decays through its mixing with a photon into fermion pairs. We therefore investigate a previously unexplored final state that contains a photon, two spatially close leptons, and large missing transverse energy. We do not observe any evidence for dark photons and set a limit on their production.
|
|
| 7. |
- Abazov, M, et al.
(författare)
-
Search for Long-Lived Charged Massive Particles with the D0 Detector
- 2009
-
Ingår i: Physical Review Letters. - 0031-9007. ; 102:16, s. 161802
-
Tidskriftsartikel (refereegranskat)abstract
- We search for long-lived charged massive particles using 1.1 fb(-1) of data collected by the D0 detector at the Fermilab Tevatron pp Collider. Time-of-flight information is used to search for pair produced long-lived tau sleptons, gauginolike charginos, and Higgsino-like charginos. We find no evidence of a signal and set 95% C.L. cross section upper limits for staus, which vary from 0.31 to 0.04 pb for stau masses between 60 and 300 GeV. We also set lower mass limits of 206 GeV (171 GeV) for pair produced charged gauginos (Higgsinos).
|
|
| 8. |
- Abazov, M, et al.
(författare)
-
Search for Resonant Diphoton Production with the D0 Detector
- 2009
-
Ingår i: Physical Review Letters. - 0031-9007. ; 102:23, s. 231801
-
Tidskriftsartikel (refereegranskat)abstract
- We present a search for a narrow resonance in the inclusive diphoton final state using similar to 2.7 fb(-1) of data collected with the D0 detector at the Fermilab Tevatron p (p) over bar Collider. We observe good agreement between the data and the background prediction, and set the first 95% C. L. upper limits on the production cross section times the branching ratio for decay into a pair of photons for resonance masses between 100 and 150 GeV. This search is also interpreted in the context of several models of electroweak symmetry breaking with a Higgs boson decaying into two photons.
|
|
| 9. |
- Abazov, M, et al.
(författare)
-
Search for the lightest scalar top quark in events with two leptons in p(p)over-bar collisions at root s=1.96 TeV
- 2009
-
Ingår i: Physics Letters B. - 0370-2693. ; 675:3-4, s. 289-296
-
Tidskriftsartikel (refereegranskat)abstract
- We report results of a search for the pair production of the lightest supersymmetric partner of the top quark, (t) over bar (1), using a data set corresponding to an integrated luminosity of 1 fb(-1) collected by the D circle divide detector at a p (p) over bar center-of-mass energy of 1.96 TeV at the Fermilab Tevatron collider. Both scalar top quarks are assumed to decay into a b quark, a charged lepton and a scalar neutrino. The search is performed in the electron Plus muon and dielectron final states. The signal topology consists of two isolated leptons, missing transverse energy, and jets. We find no evidence for this process and exclude regions of parameter space in the framework of the minimal supersymmetric standard model.
|
|
| 10. |
- Abazov, M, et al.
(författare)
-
Search for Third Generation Scalar Leptoquarks Decaying into tau b
- 2008
-
Ingår i: Physical Review Letters. - 0031-9007. ; 101:24, s. 241802
-
Tidskriftsartikel (refereegranskat)abstract
- We have searched for third generation leptoquarks (LQ(3)) using 1.05 fb(-1) of data collected with the D0 detector at the Fermilab Tevatron Collider operating at s=1.96 TeV. We set a 95% C.L. lower limit of 210 GeV on the mass of a scalar LQ(3) state decaying solely to a b quark and a tau lepton.
|
|
