McDonald, K.T.
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SEARCH FOR EXCLUSIVE J / psi PRODUCTION

Chiang, I.H. ; Johnson, R.A. ; Kwan, B.P. ; et al.
Phys.Rev.D 34 (1986) 1619, 1986.
Inspire Record 228262 DOI 10.17182/hepdata.23503

We have searched for exclusive hadronic J/ψ production by looking for narrow resonances in the e+e− mass spectrum of the reaction π−p→e+e−n. No events were observed in the region around 3.1 GeV/c2. The cross section for the reaction π−p→J/ψ n at 13 GeV/c is no more than 103 pb at the 90% confidence level.

1 data table match query
Table 1

Corrected cross section based on 7.4 pct branching ratio.


Inclusive $\mu$ - Pair Production at 150 GeV by $\pi^+$ Mesons and Protons

Anderson, K.J. ; Henry, G.G. ; McDonald, K.T. ; et al.
Phys.Rev.Lett. 37 (1976) 799, 1976.
Inspire Record 3993 DOI 10.17182/hepdata.21035

We report the measurements of the inclusive μ-pair production by 150-GeV protons and π+ mesons on beryllium. Absolute cross sections as well as the Feynman-x and PT dependence are presented in the mass region between 0.211 and 3.5 GeV/c2. Upper limits are also given for the inclusive production of η and ρ′(1600) mesons.

7 data tables match query
Table 1

DATA OBTAINED FROM FIGURE BY A.A. LEBEDEV.

Table 2

DATA OBTAINED FROM FIGURE BY A.A. LEBEDEV.

Table 3

No description provided.

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A Determination of the Pion Structure Function from Muon Pair Production

Newman, C.B. ; Anderson, K.J. ; Coleman, R.N. ; et al.
Phys.Rev.Lett. 42 (1979) 951, 1979.
Inspire Record 140037 DOI 10.17182/hepdata.20767

Data on muon-pair production by pions are used to determine the momentum distribution for valence quarks in the pion. The shape of a nucleon structure function is also obtained and is compared with a calculation based on existing data.

1 data table match query
Table 1

No description provided.


Experimental Study of Muon Pairs Produced by 252-GeV Pions on Tungsten

Conway, J.S. ; Adolphsen, C.E. ; Alexander, J.P. ; et al.
Phys.Rev.D 39 (1989) 92-122, 1989.
Inspire Record 280845 DOI 10.17182/hepdata.23151

We present the results of a study of muon pairs with invariant masses greater than 4.05 GeV/c2 produced in high-energy pion-nucleon interactions. The production cross section together with the inferred pion and nucleon structure functions are reported and compared with other experiments and with QCD predictions. The transverse-momentum distributions are also presented. Finally, the full angular distribution in cosθ and φ is given as a function of mass, Feynman x, and transverse momentum. Longitudinal photon polarization is seen in the lower portion of the mass range at high xπ. This result is compared with a higher-twist model.

18 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

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Hadronic Production of Massive Muon Pairs: Dependence on Incident Particle Type and on Target Nucleus.

Branson, J.G. ; Sanders, G.H. ; Smith, A.J.S. ; et al.
Phys.Rev.Lett. 38 (1977) 1334-1337, 1977.
Inspire Record 123331 DOI 10.17182/hepdata.21006

Data from a study of muon pairs produced in hadron-nucleus collisions are compared with the Drell-Yan model. Comparison of dimuon production by π+ and π− mesons on an isoscalar target shows evidence for a charge asymmetry characteristic of an isospin-nonconserving electromagnetic process. The average transverse momentum of the pairs increases smoothly with pair mass. Data taken on carbon and tin targets are used to extract the dependence on target atomic weight.

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


Large Transverse Momentum Photons from High-Energy Proton Proton Collisions

Darriulat, P. ; Dittmann, P. ; Eggert, K. ; et al.
Nucl.Phys.B 110 (1976) 365, 1976.
Inspire Record 109343 DOI 10.17182/hepdata.35743

We have performed a simultaneous measurement of the large transverse momentum (1.6 to 3.8 GeV/ c ) yields of single photons and of photon pairs at 90° production angle in pp collisions at ISR energies. Production cross sections for each of these two processes are compared.

0 data tables match query

EXPERIMENTAL SEARCH FOR NARROW RESONANCES IN THE REACTION PI- P ---> GAMMA GAMMA N AT 13-GEV/C

Chiang, I.H. ; Johnson, R.A. ; Kwan, B.P. ; et al.
Phys.Lett.B 140 (1984) 145-148, 1984.
Inspire Record 206508 DOI 10.17182/hepdata.30553

Using a double arm electromagnetic calorimeter we have searched for narrow states produced in the exclusive reaction π − p→γγn at 13 GeV/c. No enhancements were observed in the mass range 2.0–4.0 GeV/c 2 . For example, the 90% confidence limit on η c production is σ ( π − p→ η c n)× B ( η c → γγ ) < 44 pb.

1 data table match query
Table 1

UPPER LIMIT (90 PCT CL) FOR SIG*BR(ETA/C --> 2 GAMMA).


Production of the $J/\psi$ and $\psi^{\prime}$ (3.7) by 225 GeV/c $\pi^{\pm}$ and Proton Beams on C and SN Targets.

Branson, J.G. ; Sanders, G.H. ; Smith, A.J.S. ; et al.
Phys.Rev.Lett. 38 (1977) 1331-1334, 1977.
Inspire Record 123330 DOI 10.17182/hepdata.21022

We present results of a large-acceptance experiment in which muon pairs were observed in the mass range 0.6 to 6.0 GeV/c2. Emphasis is given to features of the production of Jψ and ψ′(3.7) particles. We find [Bσ]ψ′(3.7)[Bσ]Jψ to be 0.007±0.004 for p-C and 0.018±0.007 for π+-C interactions. Comparison with results from e+e− storage rings indicates that both the Jψ and the ψ′(3.7) are produced strongly rather than electromagnetically in our experiment.

1 data table match query
Table 1

No description provided.


Measurement of the Ratio of Sea to Valence Quarks in the Nucleon

Heinrich, J.G. ; Adolphsen, C.E. ; Alexander, J.P. ; et al.
Phys.Rev.Lett. 63 (1989) 356-359, 1989.
Inspire Record 285060 DOI 10.17182/hepdata.20030

The ratio of sea to valence quarks for nucleons in tungsten has been measured for the fractional momentum range 0.04<xN<0.36. The determination is based on the relative production rate of muon pairs by π+ and π− beams on a tungsten target. The results provide the most accurate determination to date of this ratio in the region xN<0.1 and Q2>20 GeV2, and are in good agreement with earlier measurements.

1 data table match query
Table 1

No description provided.


Higher twist effects in the reaction pi- N ---> mu+ mu- X at 253-GeV/c

Heinrich, J.G. ; Biino, C. ; Greenhalgh, J.F. ; et al.
Phys.Rev.D 44 (1991) 1909-1932, 1991.
Inspire Record 324652 DOI 10.17182/hepdata.22829

The distributions of quarks in the pion and nucleon are extracted from measurements of the reaction π−N→μ+μ−X at 253 GeV/c in a naive Drell-Yan analysis, as well as QCD-corrected analyses at leading-log and next-to-leading-log order. As xπ→1 the pion structure function shows a term that varies as 1mμμ4, which we interpret as a higher-twist effect. Additionally, the angular distribution of the μ+ in the muon-pair rest frame tends towards sin2θ as xπ→1 and as mμμ→0 in a manner consistent with higher-twist effects. When the strongly mass-dependent higher-twist effects are included as part of the pion structure function, the nucleon structure function agrees well with leading-twist results from deeply inelastic lepton-hadron scattering. A significant advance of the present work is the extension of the analysis to low masses by the subtraction of the Jψ and ψ′ resonances from the continuum. Our analysis covers the kinematic range 0.4<xπ<1.0 and 0.02<xN<0.33 with 3.0<mμμ<8.55 GeV/c2. Cross sections for ψ′ production are presented in an appendix.

3 data tables match query
Table 1

No description provided.

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No description provided.