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High-Energy Physics with Hydrogen Bubble Chambers

Description: Five years ago, our laboratory undertook to adapt the bubble chamber, newly invented by Glaser, to operation with liquid hydrogen, and in large sizes. It was hoped taht this development would yield important new experimental data when the Bevatron was completed. Accompanying papers by other members of the hydrogen bubble chamber group describe the various chambers built in the five year period and the asociated data-reduction apparatus that is needed for efficient utilization of the chambers. Experiments with the 10-cm chamber have yielded interesting data on the interaction of 300-Mev bremsstrahlung radiation with protons, and have shown that a hydrogen bubble chamber is a convenient neutron spectrometer in the 10- to 25-Mev range, the full width (at half maximum) of the 14-mev neutron line from T + D is 1 Mev. This paper, however, describes only those experiments performed at the Bevatron with chambers of 25 cm and 40 cm.
Date: October 14, 1958
Creator: Alvarez, Luis W.
Partner: UNT Libraries Government Documents Department


Description: Increased activities in Cryogenic Engineering have brought about the need for a compilation of available data. The purpose of the Cryogenic Data Book is to provide a condensed source of reliable data and reference information for those working in the cryogenic field. Specifically the data were compiled with a view toward the design of liquid hydrogen bubble chambers.
Date: May 15, 1956
Creator: Engineerin, National Bureau of Standards. Cryogenic; Chelton, Dudley B.; Mann, Douglas B.; Byrns, R.A. & Hoard, H.S.
Partner: UNT Libraries Government Documents Department


Description: In order to study resonances in the {Sigma}-{pi} system, we have analyzed reactions in which a {Sigma} hyperon and two or three pions are produced in K{sup -}-p interactions at 1.22 {+-} 0.040 and 1.51 {+-} 0.050 GeV/c incident K{sup -} momentum (i. e., 1895 and 2025 MeV center-of-mass energy), using the Lawrence Radiation Laboratory's 72-in. hydrogen bubble chamber.
Date: June 12, 1962
Creator: Alston, Margaret H.; Alvarez, Luis W.; Ferro-Luzzi, Massimiliano; Rosenfeld, Arthur H..; Ticho, Harold K. & Wojcicki, Stanley G.
Partner: UNT Libraries Government Documents Department

Liquid Hydrogen Bubble Chambers

Description: After the first hydrocarbon bubble chambers were built by Donald Glaser in 1952, work was started at Chicago and Berkeley to find if liquid hydrogen could be used as the working fluid in a bubble chamber. In the fall of 1953, it was found by the Chicago group that superheated liquid hydrogen could be made to boil under the influence of ionizing radiation, but no tracks were observed. The observation of tracks at Berkeley a few months later completed the proof that hydrogen was a usable bubble chamber liquid. (Irradiated liquid nitrogen boils when superheated, but as of spring 1956 no one has seen tracks in liquid nitrogen.) In the past two years, the Chicago group has built several all-glass hydrogen chambers, the most recent of which is approximately 5.5 by 5.5 by 20 cm inside dimensions. Their chambers have been of the so-called clean variety (like Glaser's eariy ones), in which no boiling takes place unless ionizing particles aze present. They have used their latest chamber in an extensive study of the scattering of low-energy pions by protons.
Date: April 4, 1956
Creator: Alvarez, Luis W.
Partner: UNT Libraries Government Documents Department

Fast Electronics in High-Energy Physics

Description: A brief review of fast electronics is given, leading up to the present state of the art. Cherenkov counters in high-energy physics are discussed, including an example of a velocity-selecting Cherenkov counter. An electronic device to aid in aligning external beams from high-energy accelerators is described. A scintillation-counter matrix to identify bubble chamber tracks is discussed. Some remarks on the future development of electronics in high-energy physics experiments are included.
Date: August 8, 1958
Creator: Weigand, Clyde
Partner: UNT Libraries Government Documents Department

Hybrid bubble chamber studies of K+ p and K- p interactions at 75-GeV/c

Description: We propose to expose the FNAL 30' liquid hydrogen bubble chamber to K{sup +} and K{sup -} beams both at 75 GeV/c. Each exposure consists of 100,000 equivalent K pictures. We plan to use the upstream tagging system currently in place and a downstream spectrometer with acceptance considerably increased over that of the current PHC system. This new downstream system will also be equipped with a lead glass photon detector with good spatial and energy resolution. We will study comparison of K{sup +} and K{sup -} results, as well as results from {pi}{sup +}, {pi}{sup -} , and {bar p} beams at this energy which are the subject of separate proposals.
Date: January 1, 1975
Creator: Bugg, W.M.; Condo, G.T.; Hart, E.L.; Handler, T.; U., /Tennessee; Cohn, H.O. et al.
Partner: UNT Libraries Government Documents Department


Description: A sample of 2500 {Xi}{sup -} and 500 {Xi}{sup 0} hyperons, produced in {Xi}K, {Xi}K{pi}, and {Xi}K{pi}{pi} final states by K{sup -} (in H{sub 2}) at incident momenta of 1.7 to 2.7 BeV/c, has been analyzed. The data are from an exposure (K-63) of 26 events/{mu}b in the 72-inch bubble chamber; approximately 85% of the {Xi}{sup -} events and 60% of the {Xi}{sup 0} events have been analyzed. For the {Xi}, they determine the spin and decay parameters a{sub {Xi}} and {Phi}{sub {Xi}} = tan{sup -1} ({beta}{sub {Xi}}/{Gamma}{sub {Xi}}). Combining their data with 900 {Xi}{sup -} and 150 {Xi}{sup 0} events from an earlier experiment (K-72), they obtain the following results: (1) {Xi} spin - J = 1/2 favored over J = 3/2 by {approx} 2.5 standard deviations; (2) {Xi} decay parameters (assuming a{sub {Lambda}} = 0.647 {+-} 0.048) - a{sub {Xi}{sup -}} = -0.398 {+-} 0.041, {Phi}{sub {Xi}{sup -}} = 9.8{sup o} {+-} 9.0{sup o}; a{sub {Xi}{sup 0}} = -0.413 {+-} 0.104. They observe {Xi}*(1530) and {Xi}*(1817); their data are insufficient for analysis of suggested {Xi}* resonances at 1705 and 1933 MeV. They measure the {Xi}*(1530) electromagnetic mass difference {Delta}m = m({Xi}*{sup -}) = m({Xi}*{sup 0}) = 2.0 {+-} 3.2 MeV. Using data, part of which has already been described, they find for {Xi}*(1530): J {ge} 3/2 favored over J = 1/2 (the J = 1/2 hypothesis is {approx} 3.5% as probable as the J = 3/2 hypothesis); J{sup P} = 3/2{sup +} favored over 3/2{sup -} by {approx} 2.8 standard deviations. For {Xi}*(1817) decaying into {Xi}*(1530) + {pi}, the hypotheses J{sup P} = 1/2{sup +}, 1/2{sup -}, 3/2{sup -}, 5/2{sup +}, 7/2{sup -}, etc. (corresponding to {ell} = 1, 2, 0 and 2, 1 and 3, and 2 and 4, respectively) are favored over other hypotheses, but results ...
Date: September 10, 1966
Creator: Merrill, Jr., Deane W.
Partner: UNT Libraries Government Documents Department


Description: The recently completed 25-inch hydrogen bubble chamber combines excellent picture quality with a fast operating cycle. The chamber has a unique optical system and is designed to take several pictures each Bevatron pulse, in conjunction with the Bevatron rapid beam ejection system. At present the chamber operates twice per Bevatron pulse. The general features of the chamber constructiosn are shown in Figs. 1 and 2. The chamber is ten inches deep at the narrowest point. The magnet is of conventional water cooled design and in present operation produces a vertical field of 18.5 kgauss. With suitable generators it has produced a field of 22.8 kgauss. The most important new features are discussed below.
Date: July 8, 1964
Creator: Alvarez, Luis W.; Gow, J.D.; Barrera, Frank; Eckman, Glenn; Shand, Jim; Watt, R. et al.
Partner: UNT Libraries Government Documents Department

Strange-Particle Production by 1170-MeV/c pi- Mesons

Description: Production of {Lambda} + K{sup 0}, {Sigma}{sup 0} + K{sup 0}, and {Sigma}{sup -} + K{sup +} by 1170-MeV/c {pi}{sup -} mesons has been studied in the Lawrence Radiation Laboratory 72-inch hydrogen bubble chamber, Cross sections, angular distributions, and polarizations are presented. The polarization of the {Sigma}{sup 0} is determined at four center-of-mass angles and found to be small everywhere. Based on published results for the reaction {pi}{sup +} + p {yields} {Sigma}{sup +}, K{sup +}, a comparison of the polarizations of {Sigma}{sup +}, {Sigma}{sup -}, and {Sigma}{sup 0} is made from the charge-independence triangle. A conclusion is reached that the {Sigma}{sup -} polarization should be large, and that the {Sigma}{sup -} and {Sigma}{sup +} polarizations should be opposite in sign.
Date: May 27, 1963
Creator: Anderson, Jared Arnold
Partner: UNT Libraries Government Documents Department

A Separated 1.17-Bev/c K- Meson Beam

Description: This report describes the design and testing of a 1.17-Bev/c separated K{sup -} beam designed in the fall of 1958 in connection with a 15-in. hydrogen bubble chamber experiment. At the target the K{sup -}/{pi}{sup -} ratio was 1/140. At the chamber, 4.0 K{sup -}-meson decay lengths from the target, and after two stages of electromagnetic separation, the K{sup -}/{pi}{sup -} ratio was 12.5, corresponding to a total pion suppression by a factor of about 10{sup 5}. The K{sup -} flux at the chamber was 0.87 K{sup -} mesons per 10{sup 10} protons impinging on the target.
Date: December 30, 1959
Creator: Eberhard, Phillippe; Good, Myron L. & Ticho, Harold K.
Partner: UNT Libraries Government Documents Department


Description: The authors report a study of the reaction K{sup -} + p {yields} {Lambda}{sup 0} + {pi}{sup +} + {pi}{sup -} produced by 1.15 Gev/c K{sup -} mesons and observed in the Lawrence Radiation Laboratory's 15-in. hydrogen bubble chamber. A preliminary report of these results was presented at the 1960 Rochester Conference. The beam was purified by two velocity spectrometers. A hyperon/observed during the run and the preliminary cross sections for various K{sup -} reactions at 1.15 Bev/c have been reported previously. Reaction (1) was the first one selected for detailed study, because it appeared to take place with relatively large probability and because the event, a 2-prong interaction accompanied by a V, was easily identified. In a volume of the chamber sufficiently restricted so that the scanning efficiency was near 100%, 255 such events were found. These events were measured, and the track data supplied to a computer which tested each event for goodness of fit to various kinematic hypotheses. The possible reactions, the distribution of events, and the corresponding cross sections are given in Table I. An event was placed in a given category of Table I if the {chi}{sup 2} probability for the other hypotheses was < 1%. It appears likely that the majority of the events in group(e) are also reactions of type (I). This belief is based on the following arguments: (1) since the kinematics of a {Lambda} {pi}{pi} fit (four constraints) are more overdetermined than those of a {Sigma}{sup 0} {pi}{pi} fit(two constraints), it is relatively easy for a {Lambda} {pi}{pi} reaction to fit a {Sigma}{sup 0} {pi}{pi} reaction, but only very few {Sigma}{sup 0} configurations can fit the {Lambda} {pi}{pi} reactions. (2) The events of group(e) when treated as {Sigma}{sup 0} {pi}{pi} reactions give a {chi}{sup 2} distribution which is much worse than ...
Date: October 24, 1960
Creator: Alston, Margaret; Alvarez, Luis W.; Eberhard, Philippe & Wojcicki, Stanley G.
Partner: UNT Libraries Government Documents Department

NAL bubble chamber proposal: K-p and p anti-p interactions at 200 GeV

Description: We propose to study K{sup -}p and {bar p}p interactions at 200 GeV in the hydrogen filled NAL 30'' bubble chamber with a supplementary visual spectrometer. We request 200,000 pictures. This exposure is intended as a follow up experiment to our proposal ''Multiparticle {pi}{sup -}p Interactions at 130 GeV and at the Highest Energy'' of April 23, 1971.
Date: April 1, 1971
Creator: Barnes, V.E.; Carmony, D.D.; Christian, R.S.; Fowler, E.C.; Gaidos, J.A.; Garfinkel, A.F. et al.
Partner: UNT Libraries Government Documents Department

anti-p d interactions from 20-GeV to 60-GeV

Description: We will study the reaction {bar p}n {yields} {bar p}p{sup {paragraph}-} at 20, 40, and 60 GeV/c in a bubble chamber experiment using a sample of 1,000,000 pictures.
Date: June 1, 1970
Creator: Bishop, J.M.; Huwe, D.O.; Reynolds, B.G.; Yarger, H.L. & U., /Ohio
Partner: UNT Libraries Government Documents Department

A search for charmed particles in pi- d at 200 GeV/c

Description: The authors have searched for evidence of charmed production in {pi}{sup -}d interactions by examining a sample of pictures from the FNAL 30-inch bubble chamber. A downstream muon detector was used to tag events in which a muon emerged. Results of the search is presented.
Date: April 1, 1975
Creator: Hayes, K.; Klems, J.H.; Ko, W.; Lander, R.L.; Pellett, D.; Yager, P. et al.
Partner: UNT Libraries Government Documents Department

Proposal to study anti-p induced reactions by means of the 15 foot bubble chamber, i.e.: - anti-p d interactions at 50-GeV/c and 80-GeV/c - anti-p p interactions at 80-GeV/c

Description: As a continuation of the work done at Strasbourg we are proposing to study the {bar p}d interactions at {approx} 50 and {approx} 80 GeV/c and also {bar p}p interactions at {approx}80 GeV/c. The exact values of the momenta are not very crucial although we would like to have the same value ( {approx}80 GeV/c) for the {bar p}d and {bar p}p experiments. Because of the lack of data in this momentum range each of the proposed runs will be interesting by itself as will be seen from the physics discussed below.
Date: June 1, 1975
Creator: Fridman, A. & /Strasbourg, IReS
Partner: UNT Libraries Government Documents Department

A proposal to study slow secondary particle distributions in pi -p and pp reactions in the 30 inch bubble chamber

Description: A set of runs for the 30 inch hydrogen bubble chamber for {pi}{sup -} and proton at various momenta is proposed for a total of 200,000 useable fames. The runs are aimed at providing quick answers to questions relating to the limiting fragmentation hypothesis as well as a preliminary survey of multiparticle final states.
Date: April 1, 1971
Creator: Eisenstein, B.; Ascoli, G.; Brown, R.; Eisenstein, L.; Hansen, J.D.; Kruse, U. et al.
Partner: UNT Libraries Government Documents Department

Study of multiparticle production in a small bubble chamber

Description: The authors propose to study 60,000 inelastic interactions in a small ({le} 80-inch) hydrogen chamber. They request four exposures of 15,000 interactions each, using both {pi}{sup -} and p as beam particles, at the two beam momenta 100 and 200 GeV/c. This requires 100,000 to 200,000 pictures, depending on the size of the chamber used. They couple this proposal to the strong recommendation that a small bubble chamber be available as soon as the machine provides experimental beams.
Date: June 1, 1970
Creator: Chapman, J.; Lys, J.; Ring, H.; Roe, B.; Sinclair, D.; VanderVelde, J. et al.
Partner: UNT Libraries Government Documents Department

KP and -kp interactions from ~ 20 - 60 GeV/c in a large liquid hydrogen bubble chamber

Description: The authors propose to study Kp and {bar K}p interactions in the energy regions immediately above those now accessible by exposing the NAL large liquid hydrogen bubble chamber to a neutral K{sub L}{sup o} beam.
Date: June 1, 1970
Creator: Crennel, D.J.; Gordon, H.; Lai, K.W.; Hough, P.V.C.; Scarr, J.M.; /Brookhaven et al.
Partner: UNT Libraries Government Documents Department