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Elastic neutrino-electron scattering: a progress report on Exp734 at Brookhaven

Description: I will report preliminary results on elastic neutrino-electron scattering from data taken with the 200 ton segmented liquid scintillator - proportional drift-tube neutrino detector at Brookhaven. Features of the detector (such as the active target and long radiation length) permit a uniquely clean signal. Prospects of results from the completed analysis and further data taking are discussed.
Date: January 1, 1983
Creator: Abe, K.; Ahrens, L.A. & Amako, K.
Partner: UNT Libraries Government Documents Department

New Measurement of A{sub b} at the Z{sup 0} Resonance Using a Vertex Charge Technique

Description: We present a new preliminary measurement of the parity-violation parameter A{sub b} using a self-calibrating vertex-charge technique. In the SLD experiment we observe hadronic decays of Z{sup 0} bosons produced in collisions between longitudinally polarized electrons and unpolarized positrons at the SLAC Linear Collider. A sample of b{bar b} events is selected using the topologically reconstructed mass of B hadrons. From our 1996-1998 data sample of approximately 400,000 hadronic Z{sup 0} decays, we obtain A{sub b} = 0.897 {+-} 0.027(stat){sub -0.034}{sup +0.036}(syst).
Date: July 20, 1999
Creator: Abe, K
Partner: UNT Libraries Government Documents Department

Direct Measurement of A{sub c} using Inclusive Charm Tagging at the SLD Detector

Description: We report a new measurement of A{sub c} using data obtained by SLD in 1993-98. This measurement uses a vertex tag technique, where the selection of a c hemisphere is based on the reconstructed mass of the charm hadron decay vertex. The method uses the 3D vertexing capabilities of SLD's CCD vertex detector and the small and stable SLC beams to obtain a high c-event tagging efficiency and purity of 28% and 82%, respectively. Charged kaons identified by the CRID detector and the charge of the reconstructed vertex provide an efficient quark-antiquark tag, with the analyzing power calibrated from the data. We obtain a preliminary result of A{sub c} = 0.603 {+-} 0.028 {+-} 0.023.
Date: July 14, 1999
Creator: Abe, K
Partner: UNT Libraries Government Documents Department

Measurement of nu/sub e/ and anti nu/sub e/ elastic scattering as a test of the standard model

Description: Various tests of standard SU(2) x U(1) model of weak interactions which can be performed by measurements of electron and muon neutrino-electron elastic scattering are reviewed. Electron neutrino-electron elastic scattering has both a neutral current part as well as a charged current part, and therefore offers a unique place to measure the interference of these two amplitudes. A measurement of the y-dependence of neutrino-electron elastic scattering can separately measure g/sub V/ and g/sub A/ as well as test for the presence of S, P, or T terms. Several measurable quantities involving cross sections and the interference term are derived from the standard model. Various design considerations for an experiment to determine the NC-CC interference term and the y-dependence of muon neutrino-electron elastic scattering are discussed.
Date: January 1, 1982
Creator: Abe, K.; Taylor, F.E. & White, D.H.
Partner: UNT Libraries Government Documents Department

Measurement of the Z{sup 0}-lepton coupling asymmetries A{sub l}

Description: The authors present direct measurements of the Z{sup 0}-lepton coupling asymmetries, A{sub e}, A{sub {mu}}, and A{sub {tau}}. It is based on a data sample selected from 170 k Z{sup 0} decays collected by the SLD detector. The Z`s are produced by collisions of polarized e{sup {minus}} with unpolarized e{sup +} bunches at SLC. The couplings are extracted from the measurement of the left-right forward-backward asymmetry for each lepton species. The preliminary results (using information from all leptonic data for A{sub e}) are: A{sub e} = 0.148 {+-} 0.016, A{sub {mu}} = 0.102 {+-} 0.033 and A{sub {tau}} = 0.190 {+-} 0.034.
Date: July 22, 1996
Creator: Abe, K.; Abe, K.; Abt, I. & Collaboration, SLD
Partner: UNT Libraries Government Documents Department

Results from the SLD barrel CRID detector

Description: We report on operational experience with and experimental performance of the SLD barrel Cherenkov Ring Imaging Detector from the 1992 and 1993 physics runs. The liquid (C{sub 6}F{sub 14}) and gas (C{sub 5}F{sub 12}) radiator recirculation systems have performed well, and the drift gas supply system has operated successfully with TMAE for three years. Cherenkov rings have been observed from both the liquid and gas radiators. The number and angular resolution of Cherenkov photons have been measured, and found to be close to design specifications.
Date: November 1, 1993
Creator: Abe, K.; Antilogus, P. & Aston, D.
Partner: UNT Libraries Government Documents Department

Measurement of p p --> p x Between 50-GeV and 400-GeV

Description: The authors present measurements of the invariant cross section for the inclusive reaction p + p {yields} p + X in the region 0.14 < |t| < 0.38 GeV{sup 2}, 100 < s < 750 GeV{sup 2} and 0.07 < M{sub x/s}{sup 2} < 0.20.
Date: September 1, 1973
Creator: Abe, K.; De Lillo, T.; Robinson, B.; Sannes, F.; /Rutgers U., Piscataway; Carr, J. et al.
Partner: UNT Libraries Government Documents Department

Negative Pion - Proton Interactions at 200 GeV/c

Description: We propose here to take 50,000 pictures of the NAL 30-inch bubble chamber, filled with hydrogen and exposed to 200 GeV/c beams of negative pions. We intend to study the technical limitations of the use of a bubble chamber for such high energy interactions. At the same time we will investigate the physics contained in the pictures as much as and as soon as possible. We expect to finish the study made only by scanning in a month and to end all studies in six months after getting film. Even in the energy of 200 GeV region, interactions will be accompanied with some slow secondary particles, which will be the object of analysis most interest. However majority of interactions may have a jet like topology. We will mainly use our FSD for the analysis of this experiment and the accuracy in momentum measurement and the separation of each track in a condensed jet may be the main subjects of our technical study. In the 30-inch bubble chamber, we propose to insert a target plate and a gamma conversion plate, if the situation of the chamber will allow to do so. A short discussion for the insertion of plates will be shown later.
Date: July 1, 1971
Creator: Kitagaki, T.; Tanaka, S.; Abe, K.; Hasegawa, K.; Sugahara, R.; Tamai, K. et al.
Partner: UNT Libraries Government Documents Department

Results on nu/sub. mu. /e elastic scattering

Description: A measurement of the nu/sub ..mu../e elastic scattering cross section is presented. These data analyzed were run at the Brookhaven AGS wide band neutrino beam ((E/sub nu/) = 1.5 GeV).
Date: January 1, 1983
Creator: Ahrens, L.A.; Aronson, S.H.; Connolly, P.L.; Callas, J.L.; Cutts, D.; Amako, K. et al.
Partner: UNT Libraries Government Documents Department

Elastic scattering of muon neutrinos at BNL

Description: In this paper measurement of the purely leptonic reactions: nu/sub ..mu../e ..-->.. nu/sub ..mu../e and anti nu/sub ..mu../e ..-->.. anti nu/sub ..mu../e, and the semileptonic reactions: nu/sub ..mu../p ..-->.. nu/sub ..mu../p and anti nu/sub ..mu../p ..-->.. anti nu/sub ..mu../p are presented and discussed in terms of the standard model. The data also places limites of interest on the magnitudes of a possible neutrino charge radius and a neutrino magnetic moment.
Date: February 1, 1987
Creator: Abe, K.; Ahrens, L.A.; Amako, K.; Aronson, S.H.; Beier, E.W.; Callas, J.L. et al.
Partner: UNT Libraries Government Documents Department

Determination of sin/sup 2/theta/sub w/ by muon neutrino and anti-neutrino scattering by electrons

Description: Total and differential cross sections for ..nu../sub ..mu../ and /bar /nu///sub ..mu../ elastic scattering by electrons were measured. The best value of sin/sup 2/theta/sub w/, obtained by fits to the differential distributions, was found to be sin/sup 2/theta/sub w/ = 0.195 +- 0.018 +- 0.013. 11 refs., 3 figs., 1 tab.
Date: January 1, 1988
Creator: Abe, K.; Ahrens, L.A.; Amako, K.; Aronson, S.H.; Beier, E.W.; Callas, J.L. et al.
Partner: UNT Libraries Government Documents Department

A preliminary improved test of the flavor independence of strong interactions

Description: The authors present an improved comparison of the strong couplings of gluons to light (u, d, and s), c, and b quarks, determined from multijet rates in flavor-tagged samples of hadronic Z{sup 0} decays recorded with the SLC Large Detector at the SLAC Linear Collider between 1993 and 1995. Flavor separation on the basis of lifetime and decay multiplicity differences among hadrons containing light, c, and b quarks was made using the SLD precision tracking system, yielding tags with high purity and low bias against {ge} 3-jet final states. They find: {alpha}{sub s}{sup uds}/{alpha}{sub s}{sup all} = 0.997 {+-} 0.011(stat) {+-} 0.011(syst) {+-} 0.005(theory), {alpha}{sub s}{sup c}/{alpha}{sub s}{sup all} = 0.984 {+-} 0.042 {+-} 0.053 {+-} 0.022, {alpha}{sub s}{sup b}/{alpha}{sub s}{sup all} = 1.022 {+-} 0.019 {+-} 0.023 {+-} 0.012.
Date: June 1, 1997
Creator: Abe, K.; Abe, K.; Akagi, T. & Collaboration, SLD
Partner: UNT Libraries Government Documents Department

Preliminary measurement of prompt D{sup {+-}} and D*{sup {+-}} meson production and D*{sup {+-}} spin alignment in hadronic Z{sup 0} decays

Description: The authors have measured the production rates as a function of scaled energy x of prompt charmed pseudoscalar D{sup {+-}} and vector D*{sup {+-}} mesons in hadronic Z{sup 0} decays. The prompt signal components were isolated from the background of D mesons from B hadron decays using impact parameters of reconstructed D{sup {+-}} {yields} K{sup {minus_plus}}{pi}{sup {+-}}{pi}{sup {+-}} and D*-daughter D{sup 0} {yields} K{sup {minus}}{pi}{sup +} and D{sup 0} {yields} K{sup {minus}}{pi}{sup +}{pi}{sup {minus}}{pi}{sup +} candidates. Using the combined meson production rates the authors have measured the fraction of hadronic Z{sup 0} decays into c{bar c}, R{sub c} = 0.182 {+-} 0.027 (stat.) {+-} 0.012 (syst.) (Preliminary). Comparison of the D*{sup {+-}} and D{sup {+-}} rates gives a direct probe of vector (V) vs. pseudoscalar (P) meson production for charmed quarks, and for x > 0.4 they have measured P{sub V} = V/(V + P) = 0.65 {+-} 0.09(stat.) {+-} 0.03(syst.) {+-} 0.03 (BR) (Preliminary). They have measured the degree of spin alignment of the D*{sup {+-}} mesons along their flight direction and find it to be consistent with zero. They compared the latter two results with QCD- and model-based predictions of charm-quark jet fragmentation.
Date: June 1, 1997
Creator: Abe, K.; Abe, K.; Akagi, T. & Collaboration, SLD
Partner: UNT Libraries Government Documents Department

Measurement of the B{sup +} and B{sup 0} lifetimes with topological vertexing at SLD

Description: The lifetimes of the B{sup +} (B{sub u}) and B{sup 0} (B{sub d}) mesons have been measured using a sample of 150,000 hadronic Z{sup 0} decays collected by the SLD experiment at the SLC between 1993 and 1995. The analysis reconstructs the decay length and charge of the B meson using a novel topological technique. This method results in a high statistics sample of 6,033 (3,665) charged (neutral) vertices. The ratio of B{sup +}:B{sup 0} decays in the charged (neutral) sample is 1.8:1 (1:2.3).
Date: July 1, 1996
Creator: Abe, K.; Abe, K.; Abt, I. & Collaboration, SLD
Partner: UNT Libraries Government Documents Department

Production of {pi}{sup {+-}}, K{sup {+-}}, K{sup 0}, K*{sup 0}, {phi}, p and {Lambda}{sup 0} in hadronic Z{sup 0} decays

Description: The authors have measured production rates as a function of momentum of the identified hadrons {pi}{sup +}, K{sup +}, K{sup 0}, K*{sup 0}, {phi}, p, {Lambda}{sup 0} and their antihadrons in inclusive hadronic Z{sup 0} decays, as well as separately in decays into light, c and b flavors. In addition they have compared hadron and antihadron production rates in light quark (rather than antiquark) jets. The SLD Cherenkov Ring Imaging Detector was used to identify charged hadrons. The vertex detector was used to tag high-purity samples of light- and b-flavor events. The electron beam polarization was used to tag samples of quark and antiquark jets. Clear flavor dependences are observed, consistent with expectations based upon measured production and decay properties of heavy hadrons. They use the light-flavor results to test the predictions of MLLA QCD and of various fragmentation models. Differences between hadron and antihadron production in light quark jets are observed at high momentum fraction, providing direct evidence that higher-momentum particles are more likely to contain a primary quark or antiquark, and they use these results to make a new direct measurement of strangeness suppression in the jet fragmentation process.
Date: June 1, 1997
Creator: Abe, K.; Abe, K.; Akagi, T. & Collaboration, SLD
Partner: UNT Libraries Government Documents Department

Symmetry tests in polarized Z{sup 0} decays to b{anti b}g

Description: Angular asymmetries have been measured in polarized Z{sup 0} decays to b{anti b}g collected by the SLD experiment at the SLC. A high purity b{anti b}g event sample is selected utilizing lifetime information given by the SLD CCD pixel vertex detector and the stable micron-size SLC beams, and the b- and {anti b}-jets are identified using lifetime information and momentum-weighted track charge. The forward-backward asymmetry is observed in the b-jet polar angle distribution, and the parity-violation parameter is measured to test the Standard Model. Two angular correlations between the three-jet plane and the Z{sup 0} polarization are studied. The CP-even and T-odd angular asymmetry, and the CP-odd and T-odd angular asymmetry are sensitive to physics beyond the Standard Model. The authors measure the expectation values of these quantities to be consistent with zero and set limits on the correlations.
Date: June 1, 1997
Creator: Abe, K.; Abe, K.; Akagi, T. & Collaboration, SLD
Partner: UNT Libraries Government Documents Department

Measurement of N* Production in p p ---> p N* between 9-GeV/c and 300-GeV/c

Description: The authors have measured the missing-mass spectrum of p + p {yields} p + MM in the region 1.5 < MM < 7.0 GeV using the acceleration ramp of the NAL machine between 9 and 300 GeV/c and the H{sub 2} jet target. They observe strong N*(1690) and N*(2190) production and are continuing the search for heavier mass resonances.
Date: August 1, 1973
Creator: Abe, K.; Alspector, J.; Bomberowitz, R.; Cohen, K.J.; Colleraine, A.P.; De Lillo, T. et al.
Partner: UNT Libraries Government Documents Department

Missing Mass Spectra from p p ---> p X from 9-GeV/c to 300-GeV/c

Description: Missing mass spectra were obtained by measuring recoil protons from the reaction p + p {yields} p + X in the Jacobian peak region at |t| = 0.175 and 0.25 (GeV/c){sup 2}. The incident momentum range from 9 to 300 GeV/c was covered continuously by taking data during the acceleration ramp of the Fermi National Accelerator Laboratory machine. Our missing mass range varied from 1.5 to 8.5 GeV and we observed the well known N*(1688) and N*(2l90) but no significant structures at higher mass.
Date: June 1, 1974
Creator: Abe, K.; Alspector, J.; Bomberowitz, R.; Cohen, K.J.; De Lillo, T.; Harrison, W.C. et al.
Partner: UNT Libraries Government Documents Department

A Proposal to Search for Charmed Particle Production Near Threshold

Description: We propose to search for charmed particle production thresholds by looking for anomalies in the ratio of K{sup -}/{pi}{sup -} production at P{sub T} {approx} 1 GeV/c as the incident energy is varied. Any anomalous behavior will be further investigated using a two arm effective mass spectrometer.
Date: November 1, 1974
Creator: Gross, D.; Nitz, D.; Olsen, S.; U., /Rochester; Abe, K.; Bomberowitz, R. et al.
Partner: UNT Libraries Government Documents Department

Inclusive Cross Sections for p n ---> p X between 50-GeV and 400-GeV

Description: The authors have measured the inclusive cross sections for the reaction p + d {yields} p + X in the region 0.14 < |t| < 0.38 GeV{sup 2}, 100 < s < 750 GeV{sup 2} and 0.80 < x < 0.93 using the acceleration ramp and deuterium gas jet target at Fermilab. These measurements are combined with the earlier measurements of p + p {yields} p + X to obtain invariant cross sections for p + n {yields} p + X.
Date: January 1, 1975
Creator: Robinson, B.; Abe, K.; Carr, J.; Keyne, J.; Pagnamenta, A.; Sannes, F. et al.
Partner: UNT Libraries Government Documents Department

Progress and commissioning of the SLD Cherenkov Ring Imaging Detector

Description: We report the recent progress of the SLD Cherenkov Ring Imaging Detector. All of the individual components of the device (TPC's, mirrors, liquid radiator trays) have been completed and installed. Almost half of the electronics packages are installed and operational, and the data acquisition system has been commissioned. The liquid C{sub 6}F{sub 14} recirculation system is functioning. The drift gas supply systems are operating well with TMAE, and the gaseous Freon C{sub 5}F{sub 12} recirculator is being brought on-line. Our monitor and control systems are fully functional. The commissioning of all 40 TPCs at full operating voltage has gone very smoothly. The system shows a remarkable immunity to the SLC backgrounds, and yields very clean events, while operating with a single electron sensitivity.
Date: November 1, 1991
Creator: Abe, K.; Hasegawa, K.; Suekane, F.; Yuta, H.; Antilogus, P.; Aston, D. et al.
Partner: UNT Libraries Government Documents Department

The endcap Cherenkov ring imaging detector at SLD

Description: The authors present the Cherenkov Ring Imaging Detector in the endcap regions of the SLD detector and report initial performance. The endcap CRID was completed and commissioned in 1993 and is fully operational for the 1994 run. First Cherenkov rings have been observed. The endcap CRID detectors and fluid systems are described and initial operational experience is discussed.
Date: May 1, 1995
Creator: Abe, K.; Hasegawa, K.; Hawegawa, Y.; Iwasaki, Y.; Suekane, F.; Yuta, H. et al.
Partner: UNT Libraries Government Documents Department

Electrostatic design of the barrel CRID (Cherenkov Ring Imaging Detector) and associated measurements

Description: We report on the electrostatic design and related measurements of the barrel Cherenkov Ring Imaging Detector for the Stanford Large Detector experiment at the Stanford Linear Accelerator Center Linear Collider. We include test results of photon feedback in TMAE-laden gas, distortion measurements in the drift boxes and corona measurements. 13 refs., 21 figs.
Date: April 1, 1990
Creator: Abe, K.; Hasegawa, K.; Suekane, F.; Yuta, H. (Tohoku Univ., Sendai (Japan). Dept. of Physics); Antilogus, P.; Aston, D. et al.
Partner: UNT Libraries Government Documents Department