Messner, R.L.
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Dimuon Production by Neutrons

Knapp, B. ; Lee, Won-Yong ; Leung, P. ; et al.
Phys.Rev.Lett. 34 (1975) 1044, 1975.
Inspire Record 2108 DOI 10.17182/hepdata.21935

A very narrow resonance with a mass of 3.1 GeV/c2 is observed in the reaction n+Be→μ++μ−+X. The total cross section for this process, as well as its P⊥2 and x distribution, are given.

1 data table
Table 1

The cross section per nucleon times the branching ratio.


Photoproduction of Narrow Resonances

Knapp, B. ; Lee, Won-Yong ; Leung, P. ; et al.
Phys.Rev.Lett. 34 (1975) 1040, 1975.
Inspire Record 2411 DOI 10.17182/hepdata.21280

A very narrow resonance with a mass of 3.105 GeV/c2 is observed in the reaction γ+Be→μ++μ−+X. The total cross section for this process, as well as its t distribution, is given.

1 data table
Table 1

THIS IS CROSS SECTION PER BERYLLIUM NUCLEUS ASSUMING ONLY COHERENT OR QUASI-ELASTIC SCATTERING FROM A SINGLE NUCLEON. FORWARD DIFFERENTIAL CROSS SECTIONS QUOTED IN TABLE 1 OF T. NASH ET AL., PRL 36, 1233 (1976).


Experimental Upper Limit on the Photoproduction Cross-Section for the psi (3105)

Martin, J.F. ; Bolon, C. ; Lanza, R.L. ; et al.
Phys.Rev.Lett. 34 (1975) 288, 1975.
Inspire Record 91767 DOI 10.17182/hepdata.21195

The experimental upper limit for the diffractive photoproduction of the ψ(3105) is 29 nb, with 90% confidence, at an average photon energy of 18.2 GeV.

1 data table
Table 1

No description provided.


Spin Parity Analysis of the B Meson

Chung, S.U. ; Protopopescu, S.D. ; Lynch, G.R. ; et al.
Phys.Rev.D 11 (1975) 2426, 1975.
Inspire Record 91530 DOI 10.17182/hepdata.24885

We have done a JP analysis of the low-mass π+ω system, using the reaction π+p→π+ωp at 7.1 GeV/c. We find that the B resonance cannot be JP=0− and must belong to the unnatural-parity series (1+, 2−, 3+,...), regardless of the amount of interference between the B and the background. If we assume that the B does not interfere with the background, we find that all JP states for the resonance are rejected except for 1+. Even if interference effects are allowed in the analysis, a good fit with reasonable parameters is obtained only with the 1+ hypothesis for the B meson. In an appendix, we give relevant theoretical formulas appropriate for a πω system with any number of spin-parity states and arbitrary degrees of interference among them.

1 data table
Table 1

TAKING INTO ACCOUNT 0- AND 1+ SMOOTH BACKGROUND UNDER THE B MESON. EVENTS WITH 1.08 < M(PI+ OMEGA) < 1.38 GEV.


Total Cross-Sections of $\pi^{\pm}$ and $K^{\pm}$ on Protons and Deuterons Between 50-GeV/c and 200-GeV/c

Carroll, A.S. ; Chiang, I.-H. ; Kycia, T.F. ; et al.
Phys.Rev.Lett. 33 (1974) 932, 1974.
Inspire Record 90204 DOI 10.17182/hepdata.21226

Total cross sections of π± and K± on protons and deuterons have been measured at 50, 100, 150, and 200 GeV/c. All of the cross sections rise with increasing momentum.

2 data tables
Table 1

No description provided.

Table 2

PARTICLE-ANTIPARTICLE CROSS SECTION DIFFERENCES - SOME COMMON ERRORS CANCEL.


Total Cross-Sections of p and anti-p on Protons and Deuterons Between 50-GeV/c and 200-GeV/c

Carroll, A.S. ; Chiang, I.-H. ; Kycia, T.F. ; et al.
Phys.Rev.Lett. 33 (1974) 928, 1974.
Inspire Record 90202 DOI 10.17182/hepdata.21291

Proton and antiproton total cross sections on protons and deuterons have been measured at 50, 100, 150, and 200 GeV/c. The proton cross sections rise with increasing momentum. Antiproton cross sections fall with increasing momentum, but the rate of fall decreases between 50 and 150 GeV/c, and from 150 to 200 GeV/c there is little change in cross section.

2 data tables
Table 1

No description provided.

Table 2

ANTIPARTICLE-PARTICLE CROSS SECTION DIFFERENCES.


Further observation of muonless neutrino-induced inelastic interactions.

Aubert, Bernard ; Benvenuti, A.C. ; Cline, D. ; et al.
Phys.Rev.Lett. 32 (1974) 1454-1457, 1974.
Inspire Record 882 DOI 10.17182/hepdata.21934

We report here additional positive results of a search for muonless neutrino- and anti-neutrino-induced events using an enriched antineutrino beam and a muon identifier of relatively high geometric detection efficiency. The ratio of muonless to muon event rates is observed to be R=0.20±0.05. We observe no background derived from ordinary neutrino or antineutrino interactions that is capable of explaining the muonless signal.

1 data table
Table 1

No description provided.


Observation of an A3 Amplitude Phase Change

Thompson, G. ; Badewitz, R.C. ; Gaidos, J.A. ; et al.
Phys.Rev.Lett. 32 (1974) 331, 1974.
Inspire Record 772 DOI 10.17182/hepdata.21334

A spin and parity decomposition is presented of the (π+π+π−) final state formed opposite a proton by incident 13-GeV/c π+ mesons. The A3 enhancement is identified as the 2− amplitude decaying to f0π+ via an S wave. A change in relative phase is noted between the 2−S amplitude and the other principal contributions; this is not incompatible with analyses of the (3π)− system. The method employs the University of Illinois three-body partialwave analysis program.

1 data table
Table 1

A3+ DEFINED AS JP=2- S-WAVE.


Study of the R Meson Produced in 13-GeV/c pi+ p Interactions

Thompson, G. ; Gaidos, J.A. ; McIlwain, R.L. ; et al.
Nucl.Phys.B 69 (1974) 220-236, 1974.
Inspire Record 759 DOI 10.17182/hepdata.32359

The missing mass spectrum opposite the proton in a 750 000 picture exposure, 13 GeV/ c π + p bubble chamber experiment, is investigated in two and four pion channels for structures observed or denied by boson spectrometers at the same energy in the reaction π − p→X − p.

2 data tables
Table 1

BREIT-WIGNER FITS.

Table 2

FOR 1.6 < M(4PI) < 1.8 GEV.


Partial Wave Analysis of the (pi+ pi+ pi-) System Through the Region of the A3 Meson

Thompson, G. ; Badewitz, R.C. ; Gaidos, J.A. ; et al.
Nucl.Phys.B 69 (1974) 381-398, 1974.
Inspire Record 760 DOI 10.17182/hepdata.32348

A recent spin-parity analysis of the π + π + π − system formed opposite a proton and a coherent deuteron by incident 13 GeV/ c 2 π + mesons, is extended to a three-pion mass of 1.9 GeV/ c . Relative proportions of the contributing partial waves are presented, from threshold, and the A 3 region is discussed in detail. Contrary to results with the (3 π ) − system, a change in phase is noted for the 2 − amplitude decaying to f 0 π + via am S-wave.

7 data tables
Table 1

FOR A3+ DEFINED AS 2+ S-WAVE WITH 1.5 < M(3PI) < 1.8 GEV).

Table 2

CONSTRAINT IMPLIES RHO(11) + RHO(1-1) = 0.

Table 3

CONSTRAINT IMPLIES RHO(11) + RHO(1-1) = 0.

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