Showing papers by "M. J. Shochet published in 2003"
TL;DR: In this paper, the authors report on measurements of differential cross sections dsigma/dp(T) for prompt charm meson production in ppmacr; collisions at sqrt[s]=1.96 TeV using 5.8+/-0.3 pb(-1) of data from the CDF II detector at the Fermilab Tevatron.
Abstract: We report on measurements of differential cross sections dsigma/dp(T) for prompt charm meson production in ppmacr; collisions at sqrt[s]=1.96 TeV using 5.8+/-0.3 pb(-1) of data from the CDF II detector at the Fermilab Tevatron. The data are collected with a new trigger that is sensitive to the long lifetime of hadrons containing heavy flavor. The charm meson cross sections are measured in the central rapidity region |y| K-pi(+), D(*+)-->D0pi(+), D+-->K-pi(+)pi(+), D(+)(s)-->phipi(+), and their charge conjugates. The measured cross sections are compared to theoretical calculations.
193 citations
TL;DR: In this paper, a search for the production of long-lived charged massive particles in a data sample of 90 pb(-1) of roots = 1.8 TeV p (p) over bar collisions recorded by the Collider Detector at Fermilab is reported.
Abstract: We report a search for the production of long-lived charged massive particles in a data sample of 90 pb(-1) of roots = 1.8 TeV p (p) over bar collisions recorded by the Collider Detector at Fermilab. The search uses the muonlike penetration and anomalously high ionization energy loss signature expected for such a particle to discriminate it from backgrounds. The data are found to agree with background expectations, and cross section limits of O(1) pb are derived using two reference models, a stable quark and a stable scalar lepton.
42 citations
TL;DR: In this paper, the MLLA cutoff scale was found to have a value of 230+/-40 MeV and the theoretical prediction of E(jet)sin theta(c) scaling was experimentally observed for the first time.
Abstract: Inclusive momentum distributions of charged particles in restricted cones around jet axes were measured in dijet events with invariant dijet masses in the range 80 to 600 GeV/c(2). Events were produced at the Fermilab Tevatron in p (p) over bar collisions with a center of mass energy of 1.8 TeV and recorded by the Collider Detector at Fermilab. The results were compared to perturbative QCD calculations carried out in the framework of the modified leading log approximation (MLLA) and assuming local parton-hadron duality. It was shown that the data follow theoretical predictions quite well over the whole range of the jet energies included in this analysis. We extracted the MLLA cutoff scale Q(eff) and found a value of 230+/-40 MeV. The theoretical prediction of E(jet)sin theta(c) scaling, where theta(c) is the cone opening angle, was experimentally observed for the first time. From the MLLA fits to the data, two more parameters were extracted: the ratio of parton multiplicities in gluon and quark jets, r=N-partons(g-jet)/N-partons(q- jet)=1.9+/-0.5, and the ratio of the number of charged hadrons to the number of predicted partons in a jet, K-LPHD(charged)=N- hadrons(charged)/N-partons=0.56+/-0.10.
33 citations
TL;DR: In a model where this boson would mediate interactions involving a massive right-handed neutrino (nu(R)) and have standard model strength couplings, these data are used to exclude a W' boson with mass between 225 and 536 GeV/c(2) at 95% confidence level.
Abstract: We report the results of a search for a W-' boson produced in p (p) over bar collisions at a center-of-mass energy of 1.8 TeV using a 106 pb(-1) data sample recorded by the Collider Detector at Fermilab. We observe no significant excess of events above background for a W-' boson decaying to a top and bottom quark pair. In a model where this boson would mediate interactions involving a massive right-handed neutrino (nu(R)) and have standard model strength couplings, we use these data to exclude a W-' boson with mass between 225 and 536 GeV/c(2) at 95% confidence level for M-W(')>M-nuR and between 225 and 566 GeV/c(2) at 95% confidence level for M-W(')
16 citations
TL;DR: In this paper, the mass difference m(D-s(+))-m(D+), where both the D-s and D+ are reconstructed in the phipi(+) decay channel, was measured using 11.6 pb(-1) of data collected by CDF II using the new displaced-track trigger.
Abstract: We present a measurement of the mass difference m(D-s(+))-m(D+), where both the D-s(+) and D+ are reconstructed in the phipi(+) decay channel. This measurement uses 11.6 pb(-1) of data collected by CDF II using the new displaced-track trigger. The mass difference is found to be m(D-s(+))-m(D+)=99.41+/-0.38(stat)+/-0.21(syst) MeV/c(2).
13 citations
TL;DR: In this paper, a search for associated production of the Y(1S) and a vector boson in 83 pb(-1) of p (p) over bar collisions at roots=1.8 TeV was presented.
Abstract: We present a search for associated production of the Y(1S) and a vector boson in 83 pb(-1) of p (p) over bar collisions at roots=1.8 TeV collected by the CDF experiment in 1994-1995. We find no evidence of the searched signal in the data, and set upper limits to the production cross sections.
12 citations
TL;DR: The results from a similar measurement performed in a subsample of pp events containing a leading (high longitudinal momentum) antiproton were reported in this paper, and large pseudorapidity gaps are presumed to be due to Pomeron exchanges and are the signature for diffraction.
Abstract: The results from a similar measurement performed in a subsample of pp events containing a leading (high longitudinal momentum) antiproton. As such, large pseudorapidity gaps are presumed to be due to Pomeron exchanges and are the signature for diffraction. The process with a leading beam particle in the final state, which is kinematically associated with an adjacent pseudorapidity gap, is known as single diffraction dissociation (SD), while that with a central gap as double diffraction dissociation (DD).
12 citations
TL;DR: In this paper, a study was performed to search for the production of a new heavy vector gauge boson in 1.8 TeV pp collisions and decaying into the tb final state.
Abstract: A study was performed to search for the production of a new heavy vector gauge boson in 1.8 TeV pp collisions and decaying into the tb final state. No evidence was obtained for a signal above the expected background contributions. A fit of the final state invariant mass distribution was used to exclude a W′ boson with 225
11 citations
TL;DR: In this paper, a search for the flavor-changing neutral current decay D/sup 0/ to mu/sup +/ mu /sup -/ in pp collisions at square root s=1.96 TeV using 65 pb/sup -1/ of data collected by the CDF II experiment at the Fermilab Tevatron Collider.
Abstract: We report on a search for the flavor-changing neutral current decay D/sup 0/ to mu /sup +/ mu /sup -/ in pp collisions at square root s=1.96 TeV using 65 pb/sup -1/ of data collected by the CDF II experiment at the Fermilab Tevatron Collider. A displaced-track trigger selects long-lived D/sup 0/ candidates in the D/sup 0/ to mu /sup +/ mu /sup -/ search channel, the kinematically similar D/sup 0/ to pi /sup +/ pi /sup -/ channel used for normalization, the Cabibbo-favored D/sup 0/ to K/sup -/ pi /sup +/ channel used to optimize the selection criteria in an unbiased manner, and their charge conjugates. Finding no signal events in the D/sup 0/ to mu /sup +/ mu /sup -/ search window, we set an upper limit on the branching fraction B(D/sup 0/ to mu /sup +/ mu /sup -/) lt or=2.5*10/sup -6/ (3.3*10/sup -6/) at the 90% (95%) confidence level.
10 citations
9 citations
TL;DR: In this paper, lepton flavor violating decays of a heavy neutral particle in pp collisions at √s = 18 TeV were studied and the position of PP collisions along the beam line was measured in the vertex time projection chamber (VTX).
Abstract: Lepton flavor violating decays of a heavy neutral particle in pp collisions at √s = 18 TeV were studied The position of PP collisions along the beam line was measured in the vertex time projection chamber (VTX) The results show no evidence for new particles with lepton flavor violating decays The limits on the cross section for production and decay of single sneutrino with R-parity violating interactions were also set
TL;DR: In this article, a search for a high mass, narrow width particle that decays directly to $e\ensuremath{\mu}$, $e \ensuredmath{\tau}$, or $\ensurem{m} \ensure m{m}.
Abstract: We report on a search for a high mass, narrow width particle that decays directly to $e\ensuremath{\mu}$, $e\ensuremath{\tau}$, or $\ensuremath{\mu}\ensuremath{\tau}$. We use approximately $110\text{ }\mathrm{p}{\mathrm{b}}^{\mathrm{\ensuremath{-}}\mathrm{1}}$ of data collected with the Collider Detector at Fermilab from 1992 to 1995. No evidence of lepton flavor violating decays is found. Limits are set on the production and decay of sneutrinos with $R$-parity violating interactions.
21 Mar 2003-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: The SVT architecture and design is briefly covered and reports on the SVT building/commissioning experience (hardware and software) and on the first results from the initial running are reported.
Abstract: The Collider Detector at Fermilab (CDF) Silicon Vertex Tracker (SVT) is a device that works inside the CDF Level 2 trigger to find and fit tracks in real time using the central silicon vertex detector information. SVT starts from tracks found by the Level 1 central chamber fast trigger and adds the silicon information to compute transverse track parameters with offline quality in about . The CDF SVT is fully installed and functional and has been exercised with real data during the spring and summer 2001. It is a complex digital device of more than 100 VME boards that performs a dramatic data reduction (only about one event in a thousand is accepted by the trigger). Diagnosing rare failures poses a special challenge and SVT internal data flow is monitored by dedicated hardware and software. This paper briefly covers the SVT architecture and design and reports on the SVT building/commissioning experience (hardware and software) and on the first results from the initial running.