Badier, J.
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The Threshold Photoproduction of pi0 on Nucleons and on Few Nucleon Systems

Argan, P. ; Audit, G. ; Bloch, A. ; et al.
Phys.Lett.B 206 (1988) 4, 1988.
Inspire Record 251858 DOI 10.17182/hepdata.29971

The absolute value of the π 0 photoproduction cross section on the proton recently measured near threshold enables to reanalyze previous data collected on 2 H, 3 He, and 4 He relatively to the proton. Absolute cross sections are presented for these nuclei in the energy region extending up to 10 MeV above threshold. The threshold s-wave amplitudes for 2 H and 3 He thus obtained are discussed in relation with the neutron threshold amplitude E ( nπ 0 ) 0+ value.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Measurement of the Spin Density Matrix of $D^*$ Mesons Produced in $e^+ e^-$ Annihilations

The HRS collaboration Abachi, S. ; Akerlof, C. ; Baringer, P. ; et al.
Phys.Lett.B 199 (1987) 585-590, 1987.
Inspire Record 250823 DOI 10.17182/hepdata.30012

Vector mesons produced in the reaction e + e − →V+X at √ s =29 GeV were isolated by observing D ∗ mesons through the D ∗+ → D 0 π + decay. The D 0 decay modes used are D 0 →K3 π , K π , K π , and K π ( π 0 ). The data, which correspond to an integrated luminosity of 300 pb −1 , were collected by the High Resolution Spectrometer at PEP. Spin density matrix elements for the D ∗ meson are measured as a function of the energy sharing variable Z D ∗ . There is no evidence for alignment of D ∗ mesons produced in e + e − annihilation at our energy.

6 data tables
Table 1

Spin density matrix for D0 --> K PI decay mode.

Table 2

Spin density matrix for D0 --> K 3PI decay mode.

Table 3

Spin density matrix for D0 --> K PI (PI0) decay mode.

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Search for New Heavy Quarks at the CERN Proton - anti-Proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Z.Phys.C 37 (1988) 505-525, 1988.
Inspire Record 250763 DOI 10.17182/hepdata.15651

A search has also been made for a fourth generation, charge 1/3 quark (b'). Assuming that theb' mass is smaller than that of the top quark and that it can-not be produced inW decays, the mass limits, using the above procedures, are respectivelymb'>32 GeV/c2 andmb'>44 GeV/c2, both at 95% confidence level.

0 data tables

Study of Heavy Flavor Production in Events With a Muon Accompanied by Jet(s) at the {CERN} Proton - Anti-proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Z.Phys.C 37 (1988) 489-503, 1988.
Inspire Record 250762 DOI 10.17182/hepdata.15677

We present a study of heavy flavour (charm and beauty) production using data collected with the UA1 detector at the CERN Proton-Antiproton collider at a centre-of-mass energy of 630 GeV for an integrated luminosity of 556 nb−1. This follows our earlier study ofb\(\bar b\) andc\(\bar c\) production in dimuon events and the evidence for mixing betweenB0 and\(\bar B^0 \) states. Properties of an inclusive sample of events containing a muon withpT>6 GeV/c are compared with QCD predictions for heavy flavour production, using the ISAJET Monte Carlo program. The predicted largepT muon yield from heavy flavour production and decay agrees with the data to within 30%. For events with a muon ofpT>10 GeV/c and at least one jet withET>10 GeV, we measure the ratio charm/(charm+beauty) to be (24±8±9)%. We also show that the correlations observed between the two heavy quark jets expected by flavour conservation are consistent with the mixture of lowest and higher order QCD processes. We study in detail the topological and kinematic properties of a subsample of events containing a highpT muon and one or more jets. The good agreement of the theoretical predictions with our data in a region dominated by the production of charm and beauty shows that one of the main background sources to a new heavy quark signature is well understood.

3 data tables
Table 1

No description provided.

Table 2

Numerical values supplied by K.Wacker. Muon spectrum with at least one jet with PT > 12 GeV/c.

Table 3

No description provided.


Version 2
High Transverse Momentum Prompt Photon Production by $\pi^-$ and $\pi^+$ on Protons at 280-{GeV}/$c$

The WA70 collaboration Bonesini, M. ; Bonvin, E. ; Boóth, P.S. L. ; et al.
Z.Phys.C 37 (1988) 535, 1988.
Inspire Record 250394 DOI 10.17182/hepdata.15649

The inclusive cross sections for prompt photon production by π− and π+ on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and FeynmanxF ranges covered are 4.0<pT<7.0GeV/c and −0.45<xF<0.55 respectively. A quantitative comparison of the prompt photon cross section with next-to-leading order QCD predictions using Duke and Owens structure functions is performed.

16 data tables
Table 1

Invariant cross section.

Table 1

Invariant cross section. UPDATE (03 DEC 2018): systematic error of 4th bin for PT = 4.37 GEV/C corrected from 13.5 to 13.2, slight corrections to PT weighted averages (4.11 -> 4.12, 4.36 -> 4.37, 4.61 -> 4.62, 5.72 -> 5.71, 6.37 -> 6.36).

Table 2

Invariant cross section.

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Charged $K^*$ Production in $e^+ e^-$ Annihilations at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Lett.B 199 (1987) 151-154, 1987.
Inspire Record 22433 DOI 10.17182/hepdata.6521

We report a measurement of the charged K ∗ (892) production in e + e − annihilations at 29 GeV center-of-mass energy. The 300 pb −1 data sample used for this analysis is obtained with the High Resolution Spectrometer at the SLAC storage ring PEP. The total mean multiplicity is measured to be 〈n K ∗± (892) 〉=0.62±0.045±0.04 per hadronic event. Evidence is also given for the production of a charged K 2 ∗ (1430) tensor meson.

6 data tables
Table 1

Extrapolation to full x-range using Lund model.

Table 2

Data requested from authors.

Table 3

Extrapolation to full x-range usisng fragmentation friction predicted by the Webber cluster model.

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Energy Dependence of the Charge Asymmetry a ($T (\pi$), $\theta$) in $\pi d$ Elastic Scattering

Smith, G.R. ; Gill, D.R. ; Ottewell, D. ; et al.
Phys.Rev.C 38 (1988) 240-250, 1988.
Inspire Record 250814 DOI 10.17182/hepdata.26223

Angular distributions of charge asymmetry A(Tπ,θ), have been measured for πd elastic scattering. Data were obtained in the backward hemisphere for pion bombarding energies of 143, 180, 220, and 256 MeV. The results are compared with predictions employing different mass and width parameters for the delta isobars.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurements of r and a Search for Heavy Quark Production in e+ e- Annihilation at s**(1/2) = 50-GeV and 52-GeV

The AMY collaboration Sagawa, H. ; Mori, T. ; Abe, K. ; et al.
Phys.Rev.Lett. 60 (1988) 93, 1988.
Inspire Record 251270 DOI 10.17182/hepdata.20143

The ratio R of the cross section for e+e− annihilation into hadronic final states to the QED cross section for muon-pair production is measured to be 4.34±0.45±0.30 and 4.23±0.20±0.21 at c.m. energies of 50 and 52 GeV, respectively. From these values of R and an analysis of the event shapes we deduce a 95%-confidence-level upper limit for the production rate of new heavy charge +23e or −13e quarks to be 0.19 units of R.

1 data table
Table 1

No description provided.


High Transverse Momentum $J/\psi$ Production at the {CERN} Proton - Anti-proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Phys.Lett.B 200 (1988) 380-390, 1988.
Inspire Record 250764 DOI 10.17182/hepdata.28173

We have studied high transverse momentum J/ψ production in p p interactions at s =630 GeV . The measured cross section times branching fraction for J/ψ→μ + μ − production with p T ⩾5 GeV / c and | y |<2.0 is 7.5±0.7±1.2 nb . The event topology is used to establish that there is J/ψ production from both the direct production of c c bound states and the decay of B hadrons. The inferred yield of J/ψ from beauty decays is compatible with our estimates of beauty production in other channels.

3 data tables
Table 2

Data extracted from figure with g3data.

Table 3

Data extracted from figure with g3data.


Observation of the Selective Coupling of $K^*$ States to the $K^- \eta$ Channel

Aston, D. ; Awaji, N. ; Bienz, T. ; et al.
Phys.Lett.B 201 (1988) 169-175, 1988.
Inspire Record 250272 DOI 10.17182/hepdata.30009

The K − η effective mass spectrum in the reaction K − p→K − π + π − π 0 p at 11 GeV/ c has a prominent peak at ≈1.75 GeV/ c 2 , which is shown to be due to the K 3 ∗ (1780) by a spherical harmonic moments analysis and amplitude decomposition; there is no significant signal for K 2 ∗ (1430). The measured branching fractions for the leading L =1 and L =2 K ∗, s, [BF(K 2 ∗ (1430)→Kη) <0.45% at the 95% CL and BF ( K 3 ∗ (1780)→ Kη )=9.4±3.4%] confirm the SU(3) prediction that the Kη channel couples preferentially to odd spin K *, s.

2 data tables
Table 1

Numerical data of acceptance corrected spherical harmonic moments requested from authors.

Table 2

Including systematic error.