| 1. |
- Schael, S, et al.
(författare)
-
Precision electroweak measurements on the Z resonance
- 2006
-
Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
-
Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
|
|
| 2. |
- Aaltonen, T., et al.
(författare)
-
Tevatron Run II combination of the effective leptonic electroweak mixing angle
- 2018
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 97:11
-
Tidskriftsartikel (refereegranskat)abstract
- Drell-Yan lepton pairs produced in the process p (p) over bar -> l(+)l(-) + X through an intermediate gamma*/Z boson have an asymmetry in their angular distribution related to the spontaneous symmetry breaking of the electroweak force and the associated mixing of its neutral gauge bosons. The CDF and D0 experiments have measured the effective-leptonic electroweak mixing parameter sin(2) theta(lept)(eff) using electron and muon pairs selected from the full Tevatron proton-antiproton data sets collected in 2001-2011, corresponding to 9-10 fb(-1) of integrated luminosity. The combination of these measurements yields the most precise result from hadron colliders, sin(2)theta(lept)(eff) = 0.23148 +/- 0.00033. This result is consistent with, and approaches in precision, the best measurements from electron-positron colliders. The standard model inference of the on-shell electroweak mixing parameter sin(2) theta(W), or equivalently the W-boson mass M-W, using the ZFITTER software package yields sin(2) theta(W) = 0.22324 +/- 0.00033 or equivalently, M-W = 80.367 +/- 0.017 GeV/c(2).
|
|
| 3. |
- Aaltonen, T., et al.
(författare)
-
Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron
- 2018
-
Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 120:4
-
Tidskriftsartikel (refereegranskat)abstract
- The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of root s = 1.96 TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is A(FB)(t (t) over bar) = 0.128 +/- 0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.
|
|
| 4. |
- Aaltonen, T., et al.
(författare)
-
Higgs boson studies at the Tevatron
- 2013
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:5, s. 052014-
-
Tidskriftsartikel (refereegranskat)abstract
- We combine searches by the CDF and D0 Collaborations for the standard model Higgs boson with mass in the range 90-200 GeV/c(2) produced in the gluon-gluon fusion, WH, ZH, t (t) over barH, and vector boson fusion processes, and decaying in the H -> b (b) over bar, H -> W+W-, H -> ZZ, H -> tau(+)tau(-), and H -> gamma gamma modes. The data correspond to integrated luminosities of up to 10 fb(-1) and were collected at the Fermilab Tevatron in p (p) over bar collisions at root s = 1.96 TeV. The searches are also interpreted in the context of fermiophobic and fourth generation models. We observe a significant excess of events in the mass range between 115 and 140 GeV/c(2). The local significance corresponds to 3.0 standard deviations at m(H) = 125 GeV/c(2), consistent with the mass of the Higgs boson observed at the LHC, and we expect a local significance of 1.9 standard deviations. We separately combine searches for H -> b (b) over bar, H -> W+W-, H -> tau(+)tau(-), and H -> gamma gamma. The observed signal strengths in all channels are consistent with the presence of a standard model Higgs boson with a mass of 125 GeV/c(2).
|
|
| 5. |
- Aaltonen, T., et al.
(författare)
-
Combination of measurements of the top-quark pair production cross section from the Tevatron Collider
- 2014
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:7
-
Tidskriftsartikel (refereegranskat)abstract
- We combine six measurements of the inclusive top-quark pair (t(sic)) production cross section (sigma(t)(sic)) from data collected with the CDF and D0 detectors at the Fermilab Tevatron with proton-antiproton collisions at root s = 1.96 TeV. The data correspond to integrated luminosities of up to 8.8 fb(-1). We obtain a value of sigma tt = 7.60 +/- 0.41 pb for a top-quark mass of m(t) = 172.5 GeV. The contributions to the uncertainty are 0.20 pb from statistical sources, 0.29 pb from systematic sources, and 0.21 pb from the uncertainty on the integrated luminosity. The result is in good agreement with the standard model expectation of 7.35(-0.33)(+0.28) pb at next-to-next-to-leading order and next-to-next-to leading logarithms in perturbative QCD.
|
|
| 6. |
- Aaltonen, T., et al.
(författare)
-
Observation of s-Channel Production of Single Top Quarks at the Tevatron
- 2014
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 112:23
-
Tidskriftsartikel (refereegranskat)abstract
- We report the first observation of single-top-quark production in the s channel through the combination of the CDF and D0 measurements of the cross section in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7 fb(-1) per experiment. The measured cross section is sigma(s) = 1.29(-0.24)(+0.26) pb. The probability of observing a statistical fluctuation of the background to a cross section of the observed size or larger is 1.8 x 10(-10), corresponding to a significance of 6.3 standard deviations for the presence of an s-channel contribution to the production of single-top quarks.
|
|
| 7. |
- Aaltonen, T., et al.
(författare)
-
Tevatron Constraints on Models of the Higgs Boson with Exotic Spin and Parity Using Decays to Bottom-Antibottom Quark Pairs
- 2015
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 114:15
-
Tidskriftsartikel (refereegranskat)abstract
- Combined constraints from the CDF and D0 Collaborations on models of the Higgs boson with exotic spin J and parity P are presented and compared with results obtained assuming the standard model value J(P) = 0(+). Both collaborations analyzed approximately 10 fb(-1) of proton-antiproton collisions with a center-of-mass energy of 1.96 TeV collected at the Fermilab Tevatron. Two models predicting exotic Higgs bosons with J(P) = 0(-) and J(P) = 2(+) are tested. The kinematic properties of exotic Higgs boson production in association with a vector boson differ from those predicted for the standard model Higgs boson. Upper limits at the 95% credibility level on the production rates of the exotic Higgs bosons, expressed as fractions of the standard model Higgs boson production rate, are set at 0.36 for both the J(P) = 0(-) hypothesis and the J(P) = 2(+) hypothesis. If the production rate times the branching ratio to a bottom-antibottom pair is the same as that predicted for the standard model Higgs boson, then the exotic bosons are excluded with significances of 5.0 standard deviations and 4.9 standard deviations for the J(P) = 0(-) and J(P) = 2(+) hypotheses, respectively.
|
|
| 8. |
- Aaltonen, T., et al.
(författare)
-
Combination of CDF and D0 W-Boson mass measurements
- 2013
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:5, s. 052018-
-
Tidskriftsartikel (refereegranskat)abstract
- We summarize and combine direct measurements of the mass of the W boson in root s = 1.96 TeV proton-antiproton collision data collected by CDF and D0 experiments at the Fermilab Tevatron Collider. Earlier measurements from CDF and D0 are combined with the two latest, more precise measurements: a CDF measurement in the electron and muon channels using data corresponding to 2.2 fb(-1) of integrated luminosity, and a D0 measurement in the electron channel using data corresponding to 4.3 fb(-1) of integrated luminosity. The resulting Tevatron average for the mass of the W boson is M-W = 80387 +/- 16 MeV. Including measurements obtained in electron-positron collisions at LEP yields the most precise value of M-W = 80385 +/- 15 MeV.
|
|
| 9. |
- Aaltonen, T., et al.
(författare)
-
Tevatron Combination of Single-Top-Quark Cross Sections and Determination of the Magnitude of the Cabibbo-Kobayashi-Maskawa Matrix Element V-tb
- 2015
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 115:15
-
Tidskriftsartikel (refereegranskat)abstract
- We present the final combination of CDF and D0 measurements of cross sections for single-top-quark production in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7 fb(-1) per experiment. The t-channel cross section is measured to be sigma(t) = 2.25(-0.31)(+0.29) pb. We also present the combinations of the two-dimensional measurements of the s- vs t-channel cross section. In addition, we give the combination of the s + t channel cross section measurement resulting in sigma(s+t) = 3.30(-0.40)(+0.52) pb, without assuming the standard model value for the ratio sigma(s)/sigma(t). The resulting value of the magnitude of the top-to-bottom quark coupling is vertical bar V-tb vertical bar = 1.02(-0.05)(+0.06), corresponding to vertical bar V-tb vertical bar > 0.92 at the 95% C. L.
|
|
| 10. |
- Abazov, V. M., et al.
(författare)
-
Study of double parton interactions in diphoton plus dijet events in p<(p)over bar> collisions at root s = 1.96 TeV
- 2016
-
Ingår i: PHYSICAL REVIEW D. - 2470-0010. ; 93:5
-
Tidskriftsartikel (refereegranskat)abstract
- We use a sample of diphoton + dijet events to measure the effective cross section of double parton interactions, which characterizes the area containing the interacting partons in proton-antiproton collisions, and find it to be sigma(eff) = 19.3 +/- 1.4(stat) +/- 7.8(syst) mb. The sample was collected by the D0 detector at the Fermilab Tevatron collider in p (p) over bar collisions at root s = 1.96 TeV and corresponds to an integrated luminosity of 8.7 fb(-1).
|
|
| 11. |
- Abazov, V. M., et al.
(författare)
-
Evidence for Simultaneous Production of J/psi and Upsilon Mesons
- 2016
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 116:8
-
Tidskriftsartikel (refereegranskat)abstract
- We report evidence for the simultaneous production of J/psi and Upsilon mesons in 8.1 fb(-1) of data collected at root s = 1.96 TeV by the D0 experiment at the Fermilab p (p) over bar Tevatron Collider. Events with these characteristics are expected to be produced predominantly by gluon-gluon interactions. In this analysis, we extract the effective cross section characterizing the initial parton spatial distribution, sigma(eff) = 2.2 +/- 0.7(stat) +/- 0.9(syst) mb.
|
|
| 12. |
- Abazov, V. M., et al.
(författare)
-
Measurement of the forward-backward asymmetry of Lambda and (Lambda)over-bar production in p(p)over-bar collisions
- 2016
-
Ingår i: PHYSICAL REVIEW D. - 2470-0010. ; 93:3
-
Tidskriftsartikel (refereegranskat)abstract
- We study Lambda and (Lambda) over bar production asymmetries in p (p) over bar -> Lambda((Lambda) over bar )X, p (p) over bar -> J/psi Lambda((Lambda) over bar )X, and p (p) over bar -> mu(+/-)Lambda((Lambda) over bar )X events recorded by the D0 detector at the Fermilab Tevatron collider at root s = 1.96 TeV. We find an excess of Lambda's ((Lambda) over bar 's) produced in the proton (antiproton) direction. This forward-backward asymmetry is measured as a function of rapidity. We confirm that the (Lambda) over bar/Lambda production ratio, measured by several experiments with various targets and a wide range of energies, is a universal function of "rapidity loss," i.e., the rapidity difference of the beam proton and the lambda.
|
|
| 13. |
- Abazov, V. M., et al.
(författare)
-
Measurement of the inclusive t(t)over-bar production cross section in p(p)over-bar collisions at root s=1.96 TeV and determination of the top quark pole mass
- 2016
-
Ingår i: PHYSICAL REVIEW D. - 2470-0010. ; 94:9
-
Tidskriftsartikel (refereegranskat)abstract
- The inclusive cross section of top quark-antiquark pairs produced in p (p) over bar collisions at root s = 1.96 TeV is measured in the lepton + jets and dilepton decay channels. The data sample corresponds to 9.7 fb(-1) of integrated luminosity recorded with the D0 detector during Run II of the Fermilab Tevatron Collider. Employing multivariate analysis techniques we measure the cross section in the two decay channels and we perform a combined cross section measurement. For a top quark mass of 172.5 GeV, we measure a combined inclusive top quark-antiquark pair production cross section of sigma(t<(t)over bar) = 7.26 +/- 0.13(stat)(-0.50)(+0.57) (syst) pb which is consistent with standard model predictions. We also perform a likelihood fit to the measured and predicted top quark mass dependence of the inclusive cross section, which yields a measurement of the pole mass of the top quark. The extracted value is m(t) = 172.8 +/- 1.1(theo)(-3.1)(+3.3) (exp) GeV.
|
|
| 14. |
- Abazov, V. M., et al.
(författare)
-
B-s(0) lifetime measurement in the CP-odd decay channel B-s(0) -> J/Psi f(0)(980)
- 2016
-
Ingår i: PHYSICAL REVIEW D. - 2470-0010. ; 94:1
-
Tidskriftsartikel (refereegranskat)abstract
- The lifetime of the B-s(0) meson is measured in the decay channel B-s(0) -> J/Psi pi(+)pi(-) with 880 <= M pi+pi- <= 1080 MeV/c(2), which is mainly a CP-odd state and dominated by the f(0)(980) resonance. In 10.4 fb(-1) of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the B-s(0) meson is measured to be tau(B-s(0)) = 1.70 +/- 0.14(stat) +/- 0.05(syst) ps. Neglecting CP violation in B-s(0)/(B) over bar (0)(s) mixing, the measurement can be translated into the width of the heavy mass eigenstate of the B-s(0), Gamma(H) = 0.59 +/- 0.05(stat) +/- 0.02(syst) ps(-1).
|
|
| 15. |
- Abazov, V. M., et al.
(författare)
-
Combination of D0 measurements of the top quark mass
- 2017
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 95:11
-
Tidskriftsartikel (refereegranskat)abstract
- We present a combination of measurements of the top quark mass by the D0 experiment in the lepton + jets and dilepton channels. We use all the data collected in Run I (1992-1996) at root s = 1.8 TeV and Run II (2001-2011) at root s = 1.96 TeV of the Tevatron p (p) over bar collider, corresponding to integrated luminosities of 0.1 fb(-1) and 9.7 fb(-1), respectively. The combined result is: m(t) = 174.95 +/- 0.40(stat)+/- 0.64(syst) GeV = 174.95 +/- 0.75 GeV.
|
|
| 16. |
- Abazov, V. M., et al.
(författare)
-
Evidence for a B-s(0)pi(+/-) State
- 2016
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 117:2
-
Tidskriftsartikel (refereegranskat)abstract
- We report evidence for a narrow structure, X(5568), in the decay sequence X(5568) -> B-s(0)pi(+/-), B-s(0) -> J/psi phi, J/psi -> mu(+)mu(-), phi -> K+K-. This is evidence for the first instance of a hadronic state with valence quarks of four different flavors. The mass and natural width of this state are measured to be m = 5567.8 +/- 2.9(stat)(-1.9)(+0.9) (syst) MeV/c(2) and Gamma = 21.9 +/- 6.4(stat)(-2.5)(+5.0) (syst) MeV/c(2). If the decay is X(5568) -> B-s*pi(+/-). B-s(0)gamma pi(+/-) with an unseen gamma, m(X(5568)) will be shifted up by m(B-s*) - m(B-s(0)) similar to 49 MeV/c(2). This measurement is based on 10.4 fb(-1) of p (p) over bar collision data at root s = 1.96 TeV collected by the D0 experiment at the Fermilab Tevatron collider.
|
|
| 17. |
- Abazov, V. M., et al.
(författare)
-
Evidence for Z(c)(+/-)(3900) in semi-inclusive decays of b-flavored hadrons
- 2018
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 98:5
-
Tidskriftsartikel (refereegranskat)abstract
- We present evidence for the exotic charged charmoniumlike state Z(c)(+/-)(3900) decaying to J/psi pi(+/-) in semi-inclusive weak decays of b-flavored hadrons. The signal is correlated with a parent J/psi pi(+)pi(-) system in the invariant-mass range 4.2-4.7 GeV that would include the exotic structure Y(4260). The study is based on 10.4 fb(-1) of p (p) over bar collision data collected by the D0 experiment at the Fermilab Tevatron collider.
|
|
| 18. |
- Abazov, V. M., et al.
(författare)
-
Inclusive Production of the X(4140) State in p(p)over-bar Collisions at D0
- 2015
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 115:23
-
Tidskriftsartikel (refereegranskat)abstract
- We present a study of the inclusive production of the X(4140) state with the decay to the J/psi phi final state in hadronic collisions. Based on 10.4 fb(-1) of p (p) over bar collision data collected by the D0 experiment at the Fermilab Tevatron collider, we report the first evidence for the prompt production of an X(4140) state and find the fraction of X(4140) events originating from b hadrons to be f(b) = 0.39 +/- 0.07 (stat) +/- 0.10 (syst). The ratio of the nonprompt X(4140) production rate to the B-s(0) yield in the same channel is R = 0.19 +/- 0.05 (stat) +/- 0.07 (syst). The values of the mass M = 4152.5 +/- 1.7 (stat)(-5.4)(+/- 6.2)(syst) MeV and width Gamma = 16.3 +/- 5.6 (stat) +/- 11.4 (syst) MeV are consistent with previous measurements.
|
|
| 19. |
- Abazov, V. M., et al.
(författare)
-
Measurement of the direct CP violating charge asymmetry in B-+/- -> mu(+/-)nu D-mu(0) decays
- 2017
-
Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 95:3
-
Tidskriftsartikel (refereegranskat)abstract
- We present the first measurement of the CP violating charge asymmetry in B-+/- -> mu(+/-)nu D-mu(0) decays using the full Run II integrated luminosity of 10.4 fb(-1) in proton-antiproton collisions collected with the D0 detector at the Fermilab Tevatron Collider. We measure a difference in the yield of B- and B+ mesons in these decays by fitting the reconstructed invariant mass distributions. This results in an asymmetry of A(mu D0) = [-0.14 +/- 0.20] %, which is consistent with standard model predictions.
|
|
| 20. |
- Abazov, V. M., et al.
(författare)
-
Measurement of the Effective Weak Mixing Angle in p¯p→Z/γ∗→ℓ+ℓ− Events
- 2018
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 120:24
-
Tidskriftsartikel (refereegranskat)abstract
- We present a measurement of the effective weak mixing angle parameter sin(2)theta(l)(eff) in p (p) over bar -> Z/gamma* -> mu(+)mu(-) events at a center-of-mass energy of 1.96 TeV, collected by the D0 detector at the Fermilab Tevatron Collider and corresponding to 8.6 fb(-1) of integrated luminosity. The measured value of sin(2)theta(l)(eff)[mu mu] = 0.23016 +/- 0.00064 is further combined with the result from the D0 measurement in p (p) over bar -> Z/gamma* -> e(+)e(-) events, resulting in sin(2)theta(l)(eff)[comb] = 0.23095 +/- 0.00040. This combined result is the most precise measurement from a single experiment at a hadron collider and is the most precise determination using the coupling of the Z/gamma* to light quarks.
|
|
| 21. |
|
|
| 22. |
- Abazov, V. M., et al.
(författare)
-
Measurement of the top quark mass using the matrix element technique in dilepton final states
- 2016
-
Ingår i: PHYSICAL REVIEW D. - 2470-0010. ; 94:3
-
Tidskriftsartikel (refereegranskat)abstract
- We present a measurement of the top quark mass in p (p) over bar collisions at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron collider. The data were collected by the D0 experiment corresponding to an integrated luminosity of 9.7 fb(-1). The matrix element technique is applied to t (t) over bar events in the final state containing leptons (electrons or muons) with high transverse momenta and at least two jets. The calibration of the jet energy scale determined in the lepton + jets final state of t (t) over bar decays is applied to jet energies. This correction provides a substantial reduction in systematic uncertainties. We obtain a top quark mass of m(t) = 173.93 +/- 1.84 GeV.
|
|
| 23. |
- Abazov, V. M., et al.
(författare)
-
Measurement of top quark polarization in t(t)over-bar lepton+jets final states
- 2017
-
Ingår i: PHYSICAL REVIEW D. - 2470-0010. ; 95:1
-
Tidskriftsartikel (refereegranskat)abstract
- We present a measurement of top quark polarization in t (t) over bar pair production in p (p) over bar collisions at root s = 1.96 TeV using data corresponding to 9.7 fb(-1) of integrated luminosity recorded with the D0 detector at the Fermilab Tevatron Collider. We consider final states containing a lepton and at least three jets. The polarization is measured through the distribution of lepton angles along three axes: the beam axis, the helicity axis, and the transverse axis normal to the t (t) over bar production plane. This is the first measurement of top quark polarization at the Tevatron using lepton + jet final states and the first measurement of the transverse polarization in t (t) over bar production. The observed distributions are consistent with standard model predictions of nearly no polarization.
|
|
| 24. |
- Abazov, V. M., et al.
(författare)
-
Precise measurement of the top quark mass in dilepton decays using optimized neutrino weighting
- 2016
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 752, s. 18-26
-
Tidskriftsartikel (refereegranskat)abstract
- We measure the top quark mass in dilepton final states of t (t) over bar events in p (p) over bar collisions at root s = 1.96 TeV, using data corresponding to an integrated luminosity of 9.7 fb(-1) at the Fermilab Tevatron Collider. The analysis features a comprehensive optimization of the neutrino weighting method to minimize the statistical uncertainties. We also improve the calibration of jet energies using the calibration determined in t (t) over bar -> lepton + jets events, which reduces the otherwise limiting systematic uncertainty from the jet energy scale. The measured top quark mass is m(t) = 173.32 +/- 1.36(stat) +/- 0.85(syst) GeV.
|
|
| 25. |
- Abazov, V. M., et al.
(författare)
-
Search for Violation of CPT and Lorentz Invariance in B-s(0) Meson Oscillations
- 2015
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 115:16
-
Tidskriftsartikel (refereegranskat)abstract
- We present the first search for CPT-violating effects in the mixing of B-s(0) mesons using the full Run II data set with an integrated luminosity of 10.4 fb(-1) of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. We measure the CPT-violating asymmetry in the decay B-s(0) -> mu D-+/-(s)+/- as a function of celestial direction and sidereal phase. We find no evidence for CPT-violating effects and place limits on the direction and magnitude of flavor-dependent CPT- and Lorentz-invariance violating coupling coefficients. We find 95% confidence intervals of Delta a(perpendicular to) < 1.2 x 10(-12) GeV and (-0.8 < Delta a(T) - 0.396 Delta a(Z) < 3.9) x 10(-13) GeV.
|
|
