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Observation of Anti-deuteron Production in Electron - Positron Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Harder, G. ; et al.
Phys.Lett.B 157 (1985) 326-332, 1985.
Inspire Record 214358 DOI 10.17182/hepdata.30409

The production of antideuterons has been observed in electron-positron annihilations at center-of-mass energies around 10 GeV. Antideuterons have been identified unambiguously by their energy loss in the drift chamber, their time-of-flight and the pattern of their energy deposition in the shower counters of the ARGUS detector. The production rate in the momentum range (0.6−1.8) GeV/ c is (1.6 −0.7 +1.0 ) × 10 −5 per hadronic event.

2 data tables
Table 1

Results from 6 antideuterons detected (3 from UPSI(2S), 2 from (IS) and 1 from (4S)).

Table 2

No description provided.


Inclusive Hadronic Production Cross-Sections Measured in Proton - Nucleus Collisions at s**(1/2) = 27.4-GeV

Crittenden, J.A. ; Hsiung, Y.B. ; Kaplan, D.M. ; et al.
Phys.Rev.D 34 (1986) 2584, 1986.
Inspire Record 231109 DOI 10.17182/hepdata.23462

We present results on the production of hadrons in collisions of 400-GeV/c protons with beryllium, copper, and tungsten nuclei. The data cover the region from 5.6 to 8.0 GeV/c in the transverse momentum of the final-state hadron and from 73° to 102° in the proton-nucleon center-of-momentum frame production angle theta*. The restriction of the data to values of xT (xT=2pT/ √s ) greater than 0.4 enriches the sample with hard collisions of valence quarks. Asymmetries about theta*=90° reflect the presence of neutrons in the target nuclei. The variation of the atomic-weight dependence parameter α with production angle is discussed in the context of the phenomenology of nucleonic structure within nuclei. We also extrapolate our measurements to a ‘‘deuteron’’ target to minimize nuclear effects and compare the result to QCD calculations.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Direct Photon Production at the {CERN} $\bar{p} p$ Collider

The UA2 collaboration Appel, J.A. ; Bagnaia, P. ; Banner, M. ; et al.
Phys.Lett.B 176 (1986) 239, 1986.
Inspire Record 229895 DOI 10.17182/hepdata.30247

Using the UA2 apparatus, the inclusive cross section has been measured for production of high- p T direct photons in p̄p collisions at s =546 GeV and s =630 GeV . The results are in good agreement with QCD predictions.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Direct Photon Production From Pions and Protons at 200-{GeV}/$c$

The NA3 collaboration Badier, J. ; Bardadin-Otwinowska, M. ; Bemporad, C. ; et al.
Z.Phys.C 31 (1986) 341, 1986.
Inspire Record 219999 DOI 10.17182/hepdata.15881

Direct photon production has been studied by an experiment performed with the NA3 spectrometer at CERN, using incident negative and positive beams at 200 GeV/c interacting with an isoscalar Carbon target. Two different triggers have been used; one of them requires the photon conversion. The experiment is sensitive to direct photons produced with 3.0≦PT≦6 GeV/c and center-of-mass rapidity −0.4≦y*≦1.2. Inclusive cross sections are given for incident π± and protons, and compared with second order QCD predictions; finally an estimation of the gluon structure function of the nucleon is given.

2 data tables
Table 1

Data from conversion trigger. Statistical errors only.

Table 2

Data from calorimeter trigger. Statistical errors only.


HIGH STATISTICS INCLUSIVE phi MESON PRODUCTION AT SPS ENERGIES

The ACCMOR collaboration Dijkstra, H. ; Bailey, R. ; Belau, E. ; et al.
Z.Phys.C 31 (1986) 375-389, 1986.
Inspire Record 18260 DOI 10.17182/hepdata.15894

Inclusive ϕ meson production has been measured for 100 GeV/c and 200 GeV/c incident π−,\(\bar p\) andK−, and for 120 GeV/c and 200 GeV/c incident π+,p andK+, using a Be target. A total of 630,000 ϕ mesons has been recorded in the kinematic range 0<xF<0.4. Presented are the differential cross sectionsdσ/dxF anddσ/dpT2. The longitudinal momentum distributions show that the strange valence quarks of the incidentK mesons play an important role in ϕ meson production, even at smallxF. The decay angular distribution of the ϕ meson is evaluated in the Gottfried-Jackson frame and is expressed in the elements of the density matrix. There is a small but significant cos2θGJ dependence for smallpT, which decreases for increasingpT.

34 data tables
Table 1

Note that the data is plotted in fig. 5 a factor 5 too large. The numbers here are correct.

Table 2

Note that the data is plotted in fig 5 a factor of 5 too large. The numbers here are correct.

Table 3

Note that the data is plotted in fig. 5 a factor of 5 too large. CT = The numbers here are correct.

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Kaon production in <math altimg="si1.gif"><ovl type="bar" style="s">p</ovl>p</math> reactions at a centre-of-mass energy of 540 GeV

The Bonn UA5 & Brussels UA5 & Cambridge UA5 & CERN UA5 & Stockholm UA5 collaborations Alner, G.J. ; Alpgard, K. ; Anderer, P. ; et al.
Nucl.Phys.B 258 (1985) 90624 505-539, 1985.
Inspire Record 214234 DOI 10.17182/hepdata.8127

Using the UA5 detector, the inclusive central production of Ks<sup loc="post">0</sup> and K<sup loc="post">±</sup> mesons has been measured in non-single-diffractive interactions at the CERN SPS <math altimg="si1.gif"><ovl type="bar" style="s">p</ovl>p</math> Collider at a c.m. energy of 540 GeV. The average transverse momentum is found to be 〈pT〉 = 0.57±0.03 GeV/c in the rapidity range |y|<2.5, which is an increase of about 30% over the top ISR energy. The K/π ratio has increased from about 8% at ISR energies to 9.5±0.9±0.7% (the last error is systematic) at 540 GeV. The average number of Ks<sup loc="post">0</sup> per non-single-diffractive event is 1.1±0.1 and the inclusive inelastic cross section is estimated at 49±5 mb.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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High Transverse Momentum $\pi^0$ Production by $\pi^-$ and $\pi^+$ on Protons at 280-{GeV}/$c$

The WA70 collaboration Bonesini, M. ; Bonvin, E. ; Booth, P.S. L. ; et al.
Z.Phys.C 37 (1987) 39-50, 1987.
Inspire Record 250754 DOI 10.17182/hepdata.15679

The inclusive cross sections for π0 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<7.0 GeV/c and −0.45<xF<0.6 respectively. The data are compared with leading order QCD calculations.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A Measurement of $\pi^0$ Production at Large Transverse Momentum in $\pi^- p$, $\pi^+ p$ and $p p$ Collisions at 300-{GeV}/$c$

The NA24 collaboration De Marzo, C. ; De Palma, M. ; Favuzzi, C. ; et al.
Phys.Rev.D 36 (1987) 16, 1987.
Inspire Record 236249 DOI 10.17182/hepdata.23354

Cross sections for inclusive π0 production at large transverse momentum pT were measured in π−p, π+p, and pp collisions at 300 GeV/c. The cross-section ratio σ(π−p→π0X)/σ(π+p→π0X) was found to be consistent with unity in the pT region of 1 to 5 GeV/c. The cross-section ratio σ(π+p→π0X)/σ(pp→π0X) however is growing with increasing pT and increasing π0 c.m.-system rapidity in agreement with parton-model expectations, where the partons in the pions have on average higher momenta than in the proton.

1 data table
Table 1

THERE IS ALSO A 1 PCT UNCERTAINTY IN THE PT SCALE AND A 7 PCT UNCERTAINTY IN THE NORMALISATION.


A Measurement of Direct Photon Production at Large Transverse Momentum in $\pi^- p$, $\pi^+ p$ and $p p$ Collisions at 300-{GeV}/$c$

The NA24 collaboration De Marzo, C. ; De Palma, M. ; Favuzzi, C. ; et al.
Phys.Rev.D 36 (1987) 8, 1987.
Inspire Record 236248 DOI 10.17182/hepdata.23324

Cross sections for inclusive direct photon production in π−p, π+p, and pp collisions at 300 GeV/c are measured at transverse momenta pT up to 7 GeV/c (xT=0.6). For π−p→γX also the rapidity distribution is presented. The cross-section ratio σ(π−p→γX)/σ(π+p→γX) is found to be 1 at pT=4 GeV/c and rises with increasing pT. This observation signals the occurrence of valence-quark–antiquark annihilation. The results are in good agreement with QCD predictions.

1 data table
Table 1

THERE IS ALSO A 1 PCT UNCERTAINTY IN THE PT SCALE AND A 7 PCT UNCERTAINTY IN THE NORMALISATION.


Production of High Transverse Momentum Prompt Photons and Neutral Pions in Proton Proton Interactions at 280-GeV/c

The WA70 collaboration Bonesini, M. ; Bonvin, E. ; Booth, P.S.L. ; et al.
Z.Phys.C 38 (1988) 371, 1988.
Inspire Record 252633 DOI 10.17182/hepdata.15647

The inclusive cross sections for production of prompt photons and π0s by 280 GeV/c protons incident on a liquid hydrogen target, have been measured forpT in the range 4.0 to 6.5 GeV/c and for |xF|<0.45. A quantitative comparison of the prompt photon cross section with next-to-leading order QCD predictions using Duke and Owens structure functions is performed. Phenomenological fits to the π0 and prompt photon cross sections are given.

6 data tables
Table 1

Invariant cross section.

Table 2

No description provided.

Table 3

Invariant cross section.

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