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A proposal to study particle production spectra and multiplicities in high energy hadron-hadron collisions, and for a beam survey and quark search

Description: We propose an experimental study at the new 500 GeV accelerator of the differential cross-section for particle production in hadron-hadron collisions. The projectile, and the observed single particle, will range over all combinations of positive and negative {pi}, K and p, with momenta extending up to the highest available. Enough of the secondary particle momentum range will be covered to permit us to determine by integration the multiplicity of the produced particle. Single particles will be detected in a simple spectrometer consisting of wire chambers and a small bending magnet. The configuration of the spectrometer components will be variable so that the overall spectrometer length can be kept proportional to the secondary momentum. The momentum resolution {male}P/P = {+-}0.8% and the invariant phase space acceptance P{sup 2}d{Omega}dP/E = 1.3x10{sup -3} (GeV/c){sup 2} will then be the same at all momenta. Particle identification will be by means of threshold Cherenkov counters, with 10{sup 4}: 1 rejection up to at least 250 GeV/c. Our experimental arrangement is thought to be simple and yet powerful, and we propose its use initially with incident protons and a nuclear target for a beam survey and quark search. Subsequent measurements will be carried out with a hydrogen target in a high intensity secondary beam.
Date: June 15, 1970
Creator: Beier, E.W.; Kreinick, D.L.; Weisberg, H. & U., /Pennsylvania
Partner: UNT Libraries Government Documents Department

Studies of nuclear reaction at very low energies

Description: The deuteron radiative capture reactions on {sup 2}H, {sup 6}Li and {sup 10}B have been measured between center of mass energies of 20 and 140 keV. Of note is the observation that the gamma ray-to-charged particle branching ratio for the DD reaction appears independent of energy down to a center of mass energy of 20 keV, consistent with some and contrary to other theoretical models. We have investigated the ratio of the reactions D(d,p)T and D(d,n){sup 3}He down to c.m. energies of 3 keV and the ratio of the reactions 6Li(d,p){sup 7}Li and {sup 6}LI(d,{alpha}){sup 4}He down to a c.m. energy of 19 keV. The DD reaction ratio is independent of energy while the (d,p) branch of the D-{sup 6}Li evinces a significant enhancement at the lowest measured energies. We have continued our investigation of charged particle production from deuterium-metal systems at a modest level of activity. Noteworthy in this investigation is the observation of 3 MeV protons from deuteron beam loaded Ti and LiD targets subjected to extreme thermal disequilibria. Significant facility improvements were realized during the most recent contract period. Specifically the downstream magnetic analysis system proposed to eliminate beam induced contaminants has been installed and thoroughly tested. This improvement should allow the D(a,{gamma}){sup 6}Li reaction to be measured in the coming contract period. A scattering chamber required for the measurement of the {sup 7}Li({sup 3}He,p){sup 9}Be reaction has been designed, fabricated and installed on the accelerator. A CAMAC based charged particle identification system has been assembled also for use in our proposed measurement of the {sup 7}Li({sup 3}He, p){sup 9}Be.
Date: January 15, 1992
Creator: Cecil, F.E.
Partner: UNT Libraries Government Documents Department

Final report of the High Energy Physics Group at the University of South Alabama, April 15, 1990--April 14, 1997

Description: The experimental high energy physics group at the University of South Alabama worked on three experiments conducted at the Fermi National Accelerator Laboratory. These experiments were E-705, E-771, and E-871. The group helped in taking data, analysis of data, and for one experiment in the construction of a new spectrometer. Experiment E-705 used 300 GeV/c p, {pi}{sup {minus}}, {anti p} and {pi}{sup +} on Li to study hadronic production of charmonium and direct photon production. The authors participated in the E-705 data analysis. They helped in the assembly of the E-771 spectrometer. E-771 used 800 GeV/c p-Si interactions to study hadronic beauty production and charmonium production. The groups task was to bring up the electromagnetic calorimeter and interface it into the data acquisition system. Off-line work done for the analysis of E-771 concentrated on the electromagnetic reconstruction package. Other work done in conjunction with E-771 included the development of a tracking program that used the Hough Transformation. In March of 1994, the group joined Experiment E-871. This experiment is a search for CP violation. The group took responsibility for the scintillation trigger hodoscopes to be used by the experiment.
Date: August 15, 1998
Creator: Jenkins, C.M. & Clark, R.K.
Partner: UNT Libraries Government Documents Department

Antiprotons and the Crystal Ball

Description: During the 1998 running of the Crystal Ball experiment, a couple of brief test runs were done with the C6 beamline tuned to produce antiprotons. Specifically, one shift on July 29th produced runs 329-334 with the beam momentum set for 650 MeV/c, run 355 was done on July 31st with a 550 MeV/c beam momentum, and run 926-929 were obtained in a single shift on November 3rd, also with a beam momentum of 550 MeV/c. The beam tune for the November data was greatly superior to that of the July data, however. Therefore, only the November data have been analyzed in detail, and the results of this analysis are presented in this note. Due to the paucity of statistics that were obtained, it was decided not to attempt to publish the results. However, the results are valuable as a tool for planning a possible future program of dedicated measurements of antiproton-proton annihilation into all-neutral final states using the Crystal Ball. The data in fact show that the Crystal Ball with its large angular acceptance and multi-photon capability would be an excellent detector for such an experiment. Only one other such experiment (the Crystal Barrel experiment at CERN/LEAR) has ever been done in the past. Also in this document is a survey of published results for old antiproton-proton experiments, some discussion of physics issues that are relevant to measurements of {anti p} + p {r_arrow} all-neutral final states, and some estimates about the kinds of experiments they could contemplate doing in the C6 and D6 lines at the AGS.
Date: November 15, 1999
Creator: Allgower, C. & Peaslee, D.
Partner: UNT Libraries Government Documents Department

Crystal ball single event display

Description: The Single Event Display (SED) is a routine that is designed to provide information graphically about a triggered event within the Crystal Ball. The SED is written entirely in FORTRAN and uses the CERN-based HICZ graphing package. The primary display shows the amount of energy deposited in each of the NaI crystals on a Mercator-like projection of the crystals. Ten different shades and colors correspond to varying amounts of energy deposited within a crystal. Information about energy clusters is displayed on the crystal map by outlining in red the thirteen (or twelve) crystals contained within a cluster and assigning each cluster a number. Additional information about energy clusters is provided in a series of boxes containing useful data about the energy distribution among the crystals within the cluster. Other information shown on the event display include the event trigger type and data about {pi}{sup o}`s and {eta}`s formed from pairs of clusters as found by the analyzer. A description of the major features is given, along with some information on how to install the SED into the analyzer.
Date: October 15, 1997
Creator: Grosnick, D.; Gibson, A.; Allgower, C. & Alyea, J.
Partner: UNT Libraries Government Documents Department

Setting limits and making discoveries in CDF

Description: This paper presents the statistical methods used in setting limits and discovery significances in the search for new particles in the CDF experiment at the Fermilab Tevatron. For single-channel counting experiments the collaboration employs the classical Helene formula, with Bayesian integration over systematic uncertainties in the signal acceptance and background. For more complex cases such as spectral fits and combining channels, likelihood-based methods are used. In the discoveries of the top quark and B{sub c} meson, the significance was estimated from the probability of the null hypothesis, using toy Monte Carlo methods. Lastly, in the recent SUSY/Higgs Workshop the Higgs Working Group used a method of combining channels and experiments based on the calculation of the joint likelihood for a particular experimental outcome, and averaging over all possible outcomes.
Date: May 15, 2000
Creator: Conway, J.
Partner: UNT Libraries Government Documents Department

A limit on {sigma} {center_dot} BR (B{sub c}{sup {+-}} {yields} J/{psi} + {pi}{sup {+-}})/{sigma} {center_dot} BR(B{sub u}{sup {+-}} {yields} J/{psi} + K{sup {+-}}) in {radical}s = 1.8 TeV proton-antiproton collisions

Description: We report on the results of a search for the B{sub c} (b{bar c}) meson in the decay B{sub c}{sup +-} {yields} J/{psi} + {pi}{sup +-}. This search is guided by a control sample of decays of B{sub u} mesons to J/{psi} + K and uses {approx_equal} 75pb{sup -1} of data collected at the Collider Detector Facility (CDF) at Fermilab. The lifetime of the B{sub c} meson is unknown, so the 95% confidence level limit on {sigma} {center_dot} BR(B{sub c} {yields} {psi} + {pi})/{sigma} {center_dot} BR(B{sub u} {yields} {psi} + K) is obtained as a function of the B{sub c} lifetime.
Date: July 15, 1995
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department