Parker, D.L.
Single Differential Cross Section
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Antiproton-proton elastic scattering from 1.51–2.90 GeV/ c

Parker, D.L. ; Oh, B.Y. ; Smith, G.A. ; et al.
Nucl.Phys.B 32 (1971) 29-44, 1971.
Inspire Record 1392679 DOI 10.17182/hepdata.814

In a bubble chamber experiment, we have measured p p elastic scattering at nine momenta in the range 1.51–2.90 GeV/ c . The extrapolation of the small angle region to t = 0 is discussed and compared with results of other experiments. The differential cross sections are fitted to an adaptation of the Frahn-Venter optical model and also compared to Regge-pole model predictions.

19 data tables
Table 1

'1'. '2'. '3'.

Table 2

'1'. '3'.

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Cross-section for b jet production in anti-p p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 85 (2000) 5068-5073, 2000.
Inspire Record 531669 DOI 10.17182/hepdata.42975

Bottom quark production in pbar-p collisions at sqrt(s)=1.8 TeV is studied with 5 inverse picobarns of data collected in 1995 by the DO detector at the Fermilab Tevatron Collider. The differential production cross section for b jets in the central rapidity region (|y(b)| < 1) as a function of jet transverse energy is extracted from a muon-tagged jet sample. Within experimental and theoretical uncertainties, DO results are found to be higher than, but compatible with, next-to-leading-order QCD predictions.

1 data table
Table 1

No description provided.


rivet Analysis
The b anti-b production cross-section and angular correlations in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Lett.B 487 (2000) 264-272, 2000.
Inspire Record 499943 DOI 10.17182/hepdata.42088

We present measurements of the b-bbar production cross section and angular correlations using the D0 detector at the Fermilab Tevatron p-pbar Collider operating at sqrt(s) = 1.8 TeV. The b quark production cross section for |y(b)|<1.0 and p_T(b)>6 GeV/c is extracted from single muon and dimuon data samples. The results agree in shape with the next-to-leading order QCD calculation of heavy flavor production but are greater than the central values of these predictions. The angular correlations between b and bbar quarks, measured from the azimuthal opening angle between their decay muons, also agree in shape with the next-to-leading order QCD prediction.

3 data tables
Table 1

No description provided.

Table 2

The errors are combinations of statistical and systematic uncertainties.

Table 3

The distribution of MU+ MU- azimuthal angle difference.


Measurement of cross-section for gamma gamma ---> p anti-p

The CLEO collaboration Artuso, M. ; He, D. ; Goldberg, M. ; et al.
Phys.Rev.D 50 (1994) 5484-5490, 1994.
Inspire Record 358510 DOI 10.17182/hepdata.47137

A measurement of the cross section for γγ→pp¯ is performed at two-photon center-of-mass energies between 2.00 and 3.25 GeV. These results are obtained using e+e−→e+e−pp¯ events selected from 1.31 fb−1 of data taken with the CLEO II detector. The measured cross section is in reasonable agreement with previous measurements and is in excellent agreement with recent calculations based on a diquark model. However, leading order QCD calculations performed using the Brodsky-Lepage formalism are well below the measured cross section.

3 data tables
Table 1

Data read from graph.

Table 2

Data read from graph.

Table 3

Data read from graph.


EXCLUSIVE PRODUCTION OF PROTON - ANTI-PROTON PAIRS IN TWO PHOTON COLLISIONS AT PEP

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 36 (1987) 3506, 1987.
Inspire Record 246557 DOI 10.17182/hepdata.23356

We report cross sections for the process γγ→pp¯ at center-of-mass energies W from 2.0 to 2.8 GeV. These results have been extracted from measurements of e+e−→e+e−pp¯ at an overall center-of-mass energy of 29 GeV, using the TPC/Two-Gamma facility at the SLAC storage ring PEP. Cross sections for the untagged mode [both photons nearly real] are shown to lie well above QCD predictions. Results are also presented for the single-tagged mode [one photon in the range 0.16<Q2<1.6 (GeV/c)2].

3 data tables
Table 1

Data read from graph in preprint. Statistical errors only.

Table 2

Data read from graph. Statistical errors only.

Table 3

Data read from graph. Statistical errors only.


Limit on the B ---> u Coupling from Semileptonic B Decay

The CLEO collaboration Chen, A. ; Goldberg, M. ; Horwitz, N. ; et al.
Phys.Rev.Lett. 52 (1984) 1084, 1984.
Inspire Record 199380 DOI 10.17182/hepdata.20474

We have used the momentum spectrum of leptons produced in semileptonic B-meson decays to set a 90%-confidence-level upper limit on Γ(b→ulν)Γ(b→clν) of 4%. We also measure the semileptonic branching fractions of the B meson to be (12.0±0.7±0.5)% for electrons and (10.8±0.6±1.0)% for muons.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
Charged Meson Pair Production in $\gamma \gamma$ Interactions

Boyer, J. ; Burke, D.L. ; Butler, F. ; et al.
Phys.Rev.Lett. 56 (1986) 207, 1986.
Inspire Record 220003 DOI 10.17182/hepdata.20236

The cross section for the production of π+π− or K+K− pairs in γγ interactions is measured for mππ between 1.7 and 3.5 GeV/c2 and for two intervals of γγ center-of-mass scattering angle. Results are compared with predictions of a QCD model.

2 data tables
Table 1

Data read off graph.

Table 2

Data read off graph.


rivet Analysis
Pion and kaon pair production in photon-photon collisions

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 404, 1986.
Inspire Record 228072 DOI 10.17182/hepdata.20204

We report measurements of the two-photon processes e+e−→e+e−π+π− and e+e−→e+e−K+K−, at an e+e− center-of-mass energy of 29 GeV. In the π+π− data a high-statistics analysis of the f(1270) results in a γγ width Γ(γγ→f)=3.2±0.4 keV. The π+π− continuum below the f mass is well described by a QED Born approximation, whereas above the f mass it is consistent with a QCD-model calculation if a large contribution from the f is assumed. For the K+K− data we find agreement of the high-mass continuum with the QCD prediction; limits on f′(1520) and θ(1720) formation are presented.

5 data tables
Table 1

Data read from graph. Additional overall systematic error 20% not included.

Table 2

Data read from graph.. Additional overall systematic error 20% not included.

Table 3

Data read from graph.. Additional overall systematic error 20% not included.. The Q**2 dependence is normalized to unity for the bin centred on Q**2 = 0.

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Exclusive $\rho^0$, $\omega$ and $\phi$ Electroproduction

Cassel, D.G. ; Ahrens, L.A. ; Berkelman, Karl ; et al.
Phys.Rev.D 24 (1981) 2787, 1981.
Inspire Record 166020 DOI 10.17182/hepdata.24050

We have measured exclusive ρ0, ω, and φ meson electroproduction at the Cornell Wilson Synchrotron. The final ρ0 data sample included 4637 four-constraint e+p→e+π++π−+p events, with incident energy E=11.5 GeV and electroproduction variables Q2 and W in the region 0.7<Q2<4 GeV2 and 1.9<W<4 GeV. We find that the width of the forward ρ0 diffraction peak increases rapidly as the lifetime of the intermediate hadron states decreases below cΔτ=1 fm and that the peak is wider for longitudinal ρ0 than it is for transverse ρ0. The longitudinal-transverse cross-section ratio Rp=σLσT, obtained assuming s-channel helicity conservation, becomes constant at high Q2. At fixed W the diffractive vector-meson-dominance (VMD) model reproduces the Q2 dependence of our cross section, σ=(σT+εσL), but is is not able to account for the rapid decrease in the cross section with increasing W we observe. We find that σωσρ depends on W but is independent of Q2 for 0.7<Q2<3 GeV2 and 2.2<W<3.7 GeV. However, σω is substantially larger than the diffractive VMD cross section. Our results for σφ are consistent with the Q2 dependence of the diffractive VMD model for 0.8<Q2<4 GeV2 and 2<W<3.7 GeV, but this model again fails to predict the W dependence we observe.

8 data tables
Table 1

FOUR CHANNEL FIT TO TWO PION PRODUCTION ASSUMING NO INTERFERENCE.

Table 2

DEPENDENCE OF TOTAL, LONGITUDINAL (L) AND TRANSVERSE (U) DIFFERENTIAL CROSS SECTIONS ON C*DELTA(TAU), THE FORMATION TIME FOR VIRTUAL INTERMEDIATE HADRON STATES. DELTA(TAU) IS 1/DELTA(E) WHERE DELTA(E) IS E(RF=LAB,P=3) - NU = SQRT(NU**2 + Q2 + M(RHO)**2) - NU.

Table 3

No description provided.

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ELECTROPRODUCTION OF PI DELTA AND OTHER NONDIFFRACTIVE FINAL STATES

Day, C.T. ; Harding, D.J. ; Klinger, J.S. ; et al.
Phys.Rev.D 23 (1981) 576-586, 1981.
Inspire Record 166699 DOI 10.17182/hepdata.24078

This paper reports the results of an experiment measuring the parameters of various electroproduction reactions for a range in the electroproduction variables 0.7<Q2<4 GeV2 and 2<W2<16 GeV2. This report is limited to nondiffractive exclusive channels, with detailed results regarding the πΔ final states, statistically limited results for KΛ final states, and upper limits on the production of a number of event topologies containing a single unseen neutral particle.

16 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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