High $p_T \gamma$ and $\pi^0$ Production, Inclusive and With a Recoil Hadronic Jet, in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Sov.J.Nucl.Phys. 51 (1990) 836-845, 1990.
Inspire Record 281284 DOI 10.17182/hepdata.48816

None

3 data tables

Errors are combined statistical and systematic.

Errors are combined statistical and systematic.

Errors are combined statistical and systematic.


Direct Photon Plus Away - Side Jet Production in $p p$ Collisions at $s^1$/2 = 63-{GeV} and a Determination of the Gluon Distribution

The Axial Field Spectrometer collaboration Åkesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Z.Phys.C 34 (1987) 293, 1987.
Inspire Record 235690 DOI 10.17182/hepdata.15800

We have determined the double inclusive cross-section for opposite-side high-pT photons and away-side jets withθγ≈θjet≈90° produced inpp collisions at the CERN Intersecting Storage Rings at\(\sqrt s= 63\) GeV. Under the assumption that these events arise predominantly from the QCD gluon Compton process we have calculated the gluon structure function in the range 0.15≦x≦0.30 at an average square of the four-momentum transfer of 40 GeV2/c2. The data favour a soft gluon distribution in the proton.

2 data tables

No description provided.

No description provided.


The Production of Prompt Positrons at Low Transverse Momentum Increases With the Square of the Associated Charged Multiplicity

The Axial Field Spectrometer collaboration Åkesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 192 (1987) 463-470, 1987.
Inspire Record 244887 DOI 10.17182/hepdata.30156

We have measured the production of prompt positrons in pp collisions at √ s = 63 GeV and y = 0 in the p T interval 0.12< p T <1.0 GeV/c. The results indicate that the production of positrons at low p T (<0.4 GeV/ c ) is proportional to the square of the mean multiplicity in the central region | y | < 1. Such a quadratic dependence is not expected from final-state sources such as hadronic bremsstrahlung or hadronic decays, but is natural in models where low mass electron pairs are produced by interactions of constituents created during the collision.

3 data tables

No description provided.

No description provided.

No description provided.


Search for Direct $\gamma$ Production at Low Transverse Momentum in 63-{GeV} $p p$ Collisions

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Rev.D 36 (1987) 2615, 1987.
Inspire Record 246577 DOI 10.17182/hepdata.23325

We have searched for direct photons of low PT (≤1.0 GeV/c) at θc.m.=90° in pp collisions at √s =63 GeV. We used two independent methods: direct detection in NaI crystals and conversion to e+e− pairs. No signal is observed; the photon spectrum is well described by the decay of hadrons. The result is consistent with a direct low-PT photon signal reported at √s =12 GeV, but excludes a rapid growth of soft-photon production with √s .

1 data table

No description provided.


A Study of the Production of Two Direct Photons in $p p$ Collisions at the {CERN} {ISR}

The Axial Field Spectrometer collaboration Åkesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Z.Phys.C 32 (1986) 491-497, 1986.
Inspire Record 228954 DOI 10.17182/hepdata.15834

We have studied the processpp→γγ+X at\(\sqrt s= 63 GeV\) GeV in the central rapidity region. We report a positive signal at 96% C.L., a ratio γγ/e+e−=4.0±3.0 when the transverse momentum of each photon is above 2 GeV/c, and a cross-sectiondσ/dydMγγ=(5.5±2.7)×10−34 cm2/GeV when |y|<0.5,4<Mγγ<6 GeV.

1 data table

No description provided.


Inclusive $\eta$ Production at Low Transverse Momentum in 63-{GeV} $p p$ Collisions at the {CERN} Intersecting Storage Rings

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 178 (1986) 447, 1986.
Inspire Record 230636 DOI 10.17182/hepdata.30230

The inclusive production of η-mesons in pp collisions at √ s =63GeV and ϑ CM =90° has been measured for p T <1.5GeV/c. The η/π ratio decreases from its previously measured asymptotic value of η/π ∼ 0.5 at high transverse momentum, to η/π ≈0.3 at P T = 750MeV/c and η/π ≈ 0.01 at P T =300MeV/c, in a way that consistent with phase-space considerations, e.g. m T scaling. The η/π ratio, integrated from 0.2–1.5 GeV/ c , is found to be η/π=0.07±0.055.

1 data table

No description provided.


Multiplicity Distributions in $p \alpha$ and $\alpha \alpha$ Collisions in the {CERN} {ISR}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 119 (1982) 464, 1982.
Inspire Record 179518 DOI 10.17182/hepdata.6665

Measurements of charged particle multiplicity distributions in the central rapidity region in p-p and p-α, and α-α collisions are reported. They are better fitted to the “wounded nucleon” than to the “gluon string” model. The average transverse momenta, for all three reactions, are identical (and almost independent of multiplicity) up to very high multiplicities.

2 data tables

THE FIRST PP DATA IS AT 44 GEV, THE SECOND AT 63 GEV.

No description provided.


Anti-Baryon Production in the Central Region at the {ISR}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Nucl.Phys.B 246 (1984) 1-11, 1984.
Inspire Record 199804 DOI 10.17182/hepdata.33869

Using annihilation in a calorimeter as a trigger on antiprotons, we have measured the relative production cross sections of p , Λ and Ξ at y∼0 in the transverse momentum range 1 to 2 GeV/ c in pp collisions at √ s =63 GeV. We investigate correlations between the antibaryons and associated produced particles, and find evidence for local baryon number conservation.

1 data table

No description provided.


Inclusive Vector - Meson Production in the Central Region of $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Nucl.Phys.B 203 (1982) 27, 1982.
Inspire Record 176735 DOI 10.17182/hepdata.34135

Production of ϱ 0 , K ∗0 , K ∗0 , and φ have been measured in proton-proton collisions at the CERN Intersecting Storage Rings (ISR) at low p T in the central region. The transverse mass spectra are well described by exp (− aμ T ), with a = −6.4±0.2 GeV −1 . The cross sections for d σ/ d y| y=0 are 6.5±0.8±1.2 mb for ϱ 0 , 1.9±0.3±0.3 mb for K ∗) , 1.9±03±03 mb for K ∗0 , and 60.±0.12±0.13 mb for φ , where the first error is statistical and the second is sytematic.

2 data tables

No description provided.

No description provided.


Large Transverse Momentum Particle Production in $\alpha \alpha$ and $p p$ Collisions at the {CERN} {ISR}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Nucl.Phys.B 209 (1982) 309-320, 1982.
Inspire Record 178882 DOI 10.17182/hepdata.34016

The production of charged hadrons with high p T in αα collisions at √ s =126 GeV and pp collisions at √ s =31 and 63 GeV is compared, and the structure of the events associated with the high- p T particles is studied. The probability of finding associated particles close to the trigger particle increases strongly between √ s =31 and 63 GeV for pp collisions. For p T >2.5GeV/ c the αα/pp cross section ratio at the same energy per nucleon is measured to be 18.7 ± 2.0, to be compared with A 2 = 16, and a higher associated multiplicity is observed for αα.

1 data table

FIRST PP DATA IS AT SQRT(S)=31 AND THE SECOND PP DATA IS AT 63 GEV.