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An Experimental Study of the a-Dependence of $J/\psi$ Photoproduction

The Fermilab Tagged Photon Spectrometer collaboration Sokoloff, M.D. ; dos Anjos, J.C.C. ; Appel, J.A. ; et al.

Phys.Rev.Lett. 57 (1986) 3003, 1986.

Inspire Record 235061 DOI 10.17182/hepdata.20205

We have studied the photoproduction of Jψ mesons on H, Be, Fe, and Pb targets using real photons at a mean energy of 120 GeV. The pT2 spectra were used to separate the coherent diffractive signals from the incoherent signals. Parametrizing the per-nucleus cross sections in terms of power-law dependences, Aα, we find that αcoh=1.40±0.06±0.04 for the coherent diffractive signals and αincoh=0.94±0.02±0.03 for the incoherent signals.

1 data table

Table 1

CROSS-SECTIONS ARE RELATIVE TO THAT FOR INCOHERENT J/PSI PRODUCTION OFF BERYLLIUM.

NEW RESULTS ON NUCLEAR EFFECTS IN DEEP INELASTIC MUON SCATTERING ON DEUTERIUM AND IRON TARGETS

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.

JINR-E1-86-591, 1986.

Inspire Record 238756 DOI 10.17182/hepdata.39470

None

2 data tables

Table 1

VALUES OBTAINED USING ASSUMPTION R=0.

Table 2

VALUES OBTAINED USING ASSUMPTION R=0.

A-dependence of Polarization of $\Lambda^0$ Produced Inclusively in Neutron - Nucleus Interactions

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.

Z.Phys.C 36 (1987) 27, 1987.

Inspire Record 237043 DOI 10.17182/hepdata.39599

TheA-dependence of the polarization ofΛ0,s produced inclusively in neutron-nucleus interactions at a mean neutron momentum of about 40 GeV/c has been measured in an experiment performed using the BIS-2 spectrometer at the Serpukhov accelerator. Carbon, Aluminium and Copper targets were used. TheΛ0,s were produced in the kinematical region of 0.6<pT<1.3 GeV/c and 0.2<xF<0.9. Describing the polarization of theΛ0,s by ℘=a·A a value of (−0.15+0.07/−0.60) was obtained by a fit to our data.

2 data tables

Table 1

POLARIZATION IS DESCRIBED BY A POWER LOW: POL = C*A**B, WHERE C = -1.1, +0.4, -0.3 , A- ATOMIC NUMBER AND B = -0.15, +0.07, -0.6.

Table 2

$\Xi^-$ and $\Omega^-$ Inclusive Production in $\Xi^-$ Be Interactions at 116-{GeV}/$c$

Biagi, S.F. ; Bourquin, M. ; Brown, R.M. ; et al.

Z.Phys.C 34 (1987) 187-200, 1987.

Inspire Record 233256 DOI 10.17182/hepdata.15801

The cross sections for Ξ− and Ω− inclusive production in Ξ− Be collisions at 116 GeV/c have been measured in the kinematic domain [0.1<xF<0.9, 0<pT<1.7 GeV/c]. The integrated cross sections per nucleon are found to be about twice as large as in Ξ−p collisions. The invariant cross sections increase by a factor of 70 for the Ξ−s and of 100 for the Ω−s between the central region (xF∼0.2) and the projectile fragmentation region (xF∼0.8). In the central region, they have about the same magnitude as the ones for Ξ− and Ω− inclusive production inp nucleon collisions. The Ξ− and Ω− polarisations have been measured over the same kinematic domain and are found to be compatible with zero.

4 data tables

Table 1

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rivet Analysis
Observation of Tensor and Scalar Mesons Produced in $e^+ e^-$ Annihilation at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.

Phys.Rev.Lett. 57 (1986) 1990, 1986.

Inspire Record 18688 DOI 10.17182/hepdata.20227

The production of the tensor mesons f0(1270) and K*0(1430) and the scalar meson S(975) has been observed in e+e− annihilation at 29 GeV center-of-mass energy by use of data obtained with the high-resolution spectrometer at the SLAC e+e− storage ring PEP. The mean multiplicities for meson momenta greater than 1450 MeV/c are 〈nf0〉=0.11±0.04, 〈nK*0(1430)〉=0.10±0.06, and 〈nS〉=0.05±0.02 per hadronic event. The fragmentation functions of the tensor mesons are in good agreement with the predictions of the Webber cluster model. The data are consistent with a predominant strange-quark content on the S meson.

2 data tables

Table 1

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Table 2

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Multiplicity of Charged Particles in 800-{GeV} $p p$ Interactions

The LEBC-MPS collaboration Ammar, R. ; Aziz, T. ; Banerjee, S. ; et al.

Phys.Lett.B 178 (1986) 124-128, 1986.

Inspire Record 231133 DOI 10.17182/hepdata.6558

Results are reported concerning the charged-particle multiplicity distribution obtained in an exposure of the high-resolution hydrogen bubble chamber LEBC to a beam of 800 GeV protons at the Fermilab MPS. This is the first time that such data have been available at this energy. The distribution of the number n ch of charged particles produced in inelastic interactions obeys KNO-scaling. The average multiplicity is 〈 n ch 〉 = 10.26±0.15. For n ch ⩾8 the data can be well fitted to a negative binomial. The difference between the overall experimental multiplicity distribution and that resulting from the latter fit is in agreement with the contribution expected from diffractive processes.

5 data tables

Table 1

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BACKWARD SCATTERING IN pi- p ---> p pi-, anti-p p ---> pi+ pi-, K- p ---> p K- AND anti-p p ---> p anti-p AT 8-GeV/c AND 12-GeV/c

The CERN-Lisbon-Moscow-Neuchatel-College de France-Paris collaboration Armstrong, T.A. ; Baubillier, M. ; Brient, J.C. ; et al.

Nucl.Phys.B 284 (1987) 643, 1987.

Inspire Record 230626 DOI 10.17182/hepdata.33525

Data on the reactions π − p → p π − , p p → π + π − , K − p → pK and p p → p p at 8 and 12 GeV/ c are presented. Our results agree with line reversal symmetry (between π − p → p π − and p p → π + π − ), Regge pole behaviour for non-exotic reactions ( π − p → p π − , p p → π + π − ), and universal behaviour for exotic reactions ( p p → p p , K − p → pK − ) with d σ /d u | u =0 ∼ s −10 excluding the existence of a “glory” mechanism in p p elastic backward scattering in our energy range.

4 data tables

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A Comparison of the Particle Flow in Three Jet and Radiative Two Jet Events From $e^+ e^-$ Annihilation at $e$({CM}) = 29-{GeV}

Sheldon, P.D. ; Trilling, G. ; Petersen, A. ; et al.

Phys.Rev.Lett. 57 (1986) 1398, 1986.

Inspire Record 230941 DOI 10.17182/hepdata.20219

We have made a detailed comparison of the charged-particle flow in three-jet events (e+e−→qq¯g) and radiative two-jet events (e+e−→qq¯γ) from e+e− annihilation at Ec.m.=29 GeV. Accurate comparisons can be made because these two event types have similar topologies. In the angular region between the quark and antiquark jets, we observe substantially fewer charged tracks in the two-jet events than in the radiative three-jet events.

4 data tables

Table 1

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