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in creator/contributor: "Andreotti, M."  
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Measurement of the resonance parameters of the chi(1)(1**3P(1)) and chi(2)(1**3P(2)) states of charmonium formed in antiproton-proton annihilations

Description: The authors have studied the {sup 3}P{sub J} ({chi}{sub e}) states of charmonium in formation by antiproton-proton annihilations in experiment E835 at the Fermilab Antiproton Source. The authors report new measurements of the mass, width, and B({chi}{sub cJ} {yields} {bar p}p) x {Lambda}({chi}{sub eJ} {yields} J/{psi} + anything) for the {chi}{sub c1} and {chi}{sub c2} by means of the inclusive reaction {bar p}p {yields} {chi}{sub cJ} {yields} J/{psi} + anything {yields} (e{sup +}e{sup -}) + an… more
Date: March 1, 2005
Creator: Andreotti, M.; Bagnasco, S.; Baldini, W.; Bettoni, D.; Borreani, G.; Buzzo, A. et al.
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Partner: UNT Libraries Government Documents Department
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A Study of anti-p p ---> two neutral pseudoscalar mesons at the chi(c0)(1**3 P0) formation energy

Description: Fermilab experiment E835 has studied reactions {bar p}p {yields} {pi}{sup 0}{pi}{sup 0}, {pi}{sup 0}{eta}, {eta}{eta}, {pi}{sup 0}{eta}' and {eta}{eta}' in the energy region of the {chi}{sub c0}(1{sup 3} P{sub 0}) from 3340 MeV to 3470 MeV. Interference between resonant and continuum production is observed in the {pi}{sup 0}{pi}{sup 0} and {eta}{eta} channels, and the product of the input and output branching fractions is measured. Limits on resonant production are set for the {pi}{sup 0}{eta} … more
Date: September 1, 2005
Creator: Andreotti, M.; Bagnasco, S.; Baldini, W.; Bettoni, D.; Borreani, G.; Buzzo, A. et al.
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Partner: UNT Libraries Government Documents Department
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Precision measurements of the total and partial widths of the psi(2S) charmonium meson with a new complementary-scan technique in anti-p p annihilations

Description: We present new precision measurements of the {Psi}(2S) total and partial widths from excitation curves obtained in antiproton-proton annihilations by Fermilab experiment E835 at the Antiproton Accumulator in the year 2000. A new technique of complementary scans was developed to study narrow resonances with stochastically cooled antiproton beams. It relies on precise revolution-frequency and orbit-length measurements, while making the analysis of the excitation curve almost independent of machin… more
Date: March 1, 2007
Creator: Andreotti, M.; Bagnasco, S.; Baldini, W.; Bettoni, D.; Borreani, G.; Buzzo, A. et al.
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Partner: UNT Libraries Government Documents Department
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A Barrel IFR Instrumented With Limited Streamer Tubes for BABAR Experiment

Description: The new barrel Instrumented Flux Return (IFR) of BABAR detector will be reported here. Limited Streamer Tubes (LSTs) have been chosen to replace the existing RPCs as active elements of the barrel IFR. The layout of the new detector will be discussed: in particular, a cell bigger than the standard one has been used to improve efficiency and reliability. The extruded profile is coated with a resistive layer of graphite having a typical surface resistivity between 0.2 and 0.4 MOhm/square. The tube… more
Date: November 15, 2006
Creator: Andreotti, M.
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Partner: UNT Libraries Government Documents Department
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Measurement of the branching ratios psi-prime ---> e+ e-, psi-prime ---> J/psi pi pi and psi-prime ---> J/psi eta

Description: The authors have measured several branching ratios for {psi}' decay using the data collected by FNAL E835 experiment during year 2000, obtaining {beta}({psi}' {yields} e{sup +}e{sup -}) = 0.0068 {+-} 0.0001 {+-} 0.0004, {beta}({psi}' {yields} J/{psi}{pi}{sup +}{pi}{sup -}) = 0.292 {+-} 0.005 {+-} 0.018, {beta}({psi}' {yields} J/{psi}{pi}{sup 0}{pi}{sup 0}) = 0.167 {+-} 0.005 {+-} 0.014 and {beta}({psi}' {yields} J/{psi}{eta}) = 0.028 {+-} 0.002 {+-} 0.002. They also present a measurement of the… more
Date: February 1, 2005
Creator: Andreotti, M.; Bagnasco, S.; Baldini, W.; Bettoni, D.; Borreani, G.; Buzzo, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of the angular distribution in anti-p p ---> psi(2S) ---> e+ e-

Description: The authors present the first measurement of the angular distribution for the exclusive process {bar p}p {yields} {psi}(2S) {yields} e{sup +}e{sup -} based on a sample of 6844 events collected by the Fermilab E835 experiment. They find that the angular distribution is well described by the expected functional form dN/d cos {theta}* {proportional_to} 1 + {lambda} cos{sup 2} {theta}*, where {theta}* is the angle between the antiproton and the electron in the center of mass frame, with {lambda} = … more
Date: December 1, 2004
Creator: Ambrogiani, M.; Andreotti, M.; Argiro, S.; Bagnasco, S.; Baldini, W.; Bettoni, D. et al.
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Partner: UNT Libraries Government Documents Department
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Performance and Aging Studies of BaBar Resistive Plate Chambers

Description: The BaBar detector is currently operating nearly 200 Resistive Plate Chambers (RPCs), constructed as part of an upgrade of the forward endcap muon detector in 2002. Although the average RPC efficiency remains high, numerous changes in the RPC performance (increased currents and rates) have been observed. A few of the highest rate RPCs have suffered efficiency losses of more than 15%. Several types of efficiency loss have been observed. Tests with humidified gas have shown that some of the lost … more
Date: October 13, 2006
Creator: Band, H. R.; Hollar, J.; Tan, P.; Anulli, F.; Baldini, R.; Calcaterra, A. et al.
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Partner: UNT Libraries Government Documents Department
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Performance of 2nd Generation BaBar Resistive Plate Chambers

Description: The BaBar detector has operated nearly 200 Resistive Plate Chambers (RPCs), constructed as part of an upgrade of the forward endcap muon detector, for the past two years. The RPCs experience widely different background and luminosity-driven singles rates (0.01-10 Hz/cm{sup 2}) depending on position within the endcap. Some regions have integrated over 0.3 C/cm{sup 2}. RPC efficiency measured with cosmic rays is high and stable. The average efficiency measured with beam is also high. However, a f… more
Date: July 12, 2005
Creator: Anulli, F.; Baldini, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Patteri, P. et al.
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Partner: UNT Libraries Government Documents Department
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