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

Data from conversion trigger. Statistical errors only.

Data from calorimeter trigger. Statistical errors only.


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

The NA3 collaboration Badier, J. ; Bardadin-Otwinowska, M. ; Bemporad, C. ; et al.
Phys.Lett.B 164 (1985) 184-188, 1985.
Inspire Record 217947 DOI 10.17182/hepdata.30329

We present results from a direct photon pair search performed with the NA3 spectrometer, using incident positive and negative beams at 200 GeV/ c interacting with a carbon target. The experiment is sensitive to photons with p T >1.8 GeV / c and −0.4⩽y ∗ ⩽1.0 , one in each arm of the apparatus. A 3 standard deviation signal is seen in τ − and p interactions. The cross section is higher than the second order QCD calculations, but systematic errors are large.

1 data table

No description provided.


Inclusive High $p_T \pi^0$ Production From $\pi^\pm$ and Protons at 200-{GeV}/$c$

The NA3 collaboration Badier, J. ; Bardadin-Otwinowska, M. ; Bemporad, C. ; et al.
Z.Phys.C 30 (1986) 45, 1986.
Inspire Record 216588 DOI 10.17182/hepdata.15912

We have measured the inclusive cross-section for π0 production at large transverse momentum by 200 GeV/c positive and negative hadron beams on Carbon targets (2.9<PT<6 GeV/c; −0.4<y*<1.2). We used the NA3 spectrometer at the CERNSPS.

2 data tables

CONVERSION TRIGGER SELECTION.

CALORIMETER TRIGGER SELECTION.


$\psi \psi$ Production and Limits on Beauty Meson Production From 400-{GeV}/$c$ Protons

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
Phys.Lett.B 158 (1985) 85, 1985.
Inspire Record 213878 DOI 10.17182/hepdata.30379

From a study of multimuon events obtained in a high luminosity proton-platinum experiment at 400 GeV/ c , we find 5 ± 4 ψψ events, which correspond to a production cross section σ ( ψψ = 27 ± 10 pb. The observed production is compared to the ψψ events previously found in the same apparatus from incoming π − ; a comparison with QCD predictions is performed, giving a good agreement with expectations from gluon-gluon fusion. Finally, using like-sign dimuon, trimuon and quadrimuon events, we give model-dependent upper limits on beauty meson production: 2 nb/nucleon for central models, 20 nb/nucleon for diffractive production.

1 data table

No description provided.


STUDY OF THE LOW MASS DIMUON CONTINUUM PRODUCED IN HADRONIC INTERACTIONS

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
Phys.Lett.B 142 (1984) 446, 1984.
Inspire Record 199414 DOI 10.17182/hepdata.30530

We present here the analysis of low mass dimuon events (1.8 < M μμ < 2.6 GeV / c 2 ) produced by positive and negative pion and proton beams at 200 GeV / c . Using the difference between the π - and the π + cross sections, and comparing to the Drell-Yan model, we find a K -factor of 2.47 ± 0.5. Only about 1 2 of the events can be attributed to the Drell-Yan mechanism. If the remaining events are attributed to muonic decays of D mesons we findan upper limit for the cross section of charmed meson production.

2 data tables

No description provided.

No description provided.


{Drell-Yan} Events From 400-{GeV}/$c$ Protons: Determination of the $K$ Factor in a Large Kinematical Domain

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
Z.Phys.C 26 (1985) 489, 1985.
Inspire Record 199644 DOI 10.17182/hepdata.16140

We present the analysis of ∼30,000 high mass dimuons (Mμμ>4.5 GeV/c2) produced in 400 GeV/c proton-platinum interactions. A determination of theK-factor is given for different values ofxF andMμμ, and its variations are compared to QCD predictions. The proton structure functions derived from these events are compared to the values obtained in deep inelastic lepton scattering.

1 data table

No description provided.


Experimental J/psi Hadronic Production from 150-GeV/c to 280-GeV/c

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
Z.Phys.C 20 (1983) 101, 1983.
Inspire Record 191240 DOI 10.17182/hepdata.2212

A detailed study ofJ/ψ hadronic production has been performed in a high statistics experiment (more than 1.5 106J/ψ observed in their dimuon decay mode). Data have been taken with incident π±,K±,p±, on hydrogen and platinum targets, at 150, 200 and 280 GeV/c. We find from the observed nuclear dependance of the cross sections, that about 18% of theJ/ψ are produced diffractively. Using known structure functions of the quarks in the nucleon and in the pion, we derive estimations for the gluon structure functions.

11 data tables

No description provided.

No description provided.

No description provided.

More…

Production of Low Mass Dimuons at High Transverse Momentum: Study of $\rho$, $\omega$, $\phi$ Resonances

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
Phys.Lett.B 122 (1983) 441-447, 1983.
Inspire Record 181912 DOI 10.17182/hepdata.30755

We use low mass dimuons (0.35 < M μμ ⩽ 2 GeV/ c 2 ) to analyse the production at high transverse momentum ( P T ⩾ 2 GeV/ c ) of the resonances ϱ, ω, π. We have studied the variation of the cross section with the type of incident particle (π, K, p) at 150, 200, 280 GeV/ c and the nuclear effects by comparison of platinum and hydrogen targets. There is no significant difference between the slopes of the transverse momentum distributions with those observed at lower P T (0 < P T < 2 GeV/ c ), meanwhile x F -distributions show a leading effect in the production of gf by kaons at these relatively high transverse momenta.

3 data tables

No description provided.

No description provided.

No description provided.


Test of Nuclear Effects in Hadronic Dimuon Production

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
Phys.Lett.B 104 (1981) 335, 1981.
Inspire Record 166153 DOI 10.17182/hepdata.31167

We present the final analysis of the nuclear effects on the cross section of dimuon production, using simultaneously a hydrogen and a platinum target in a 150, 200 and 280 GeV pion beam. For the dimuon mass interval 4.1 to 8.5 GeV, the ratio of the cross sections is in agreement with the Drell-Yan model within a 10% error, mainly due to systematics. The variation of this ratio with the dimuon mass, x 1 and x 2 is also in good agreement, and no variation with the transverse momentum is observed.

5 data tables

No description provided.

No description provided.

No description provided.

More…