Study of Photons Produced Simultaneously with the J/psi Particles at the CERN Intersecting Storage Rings

Cobb, J.H. ; Iwata, S. ; Palmer, R.B. ; et al.
Phys.Lett.B 72 (1978) 497-499, 1978.
Inspire Record 122488 DOI 10.17182/hepdata.50369

As a part of the study of the inclusive production of electron pairs in pp collisions at the CERN Intersecting Storage Rings (ISR), a search has been performed for additional photons accompanying J/ψ particles. The results suggest that (43±21)% of the J/ψ's are produced via the photonic decay of one of the χ(3.5) states.

1 data table

The cross section times branching ratio.


MEASUREMENTS OF D (SIGMA) DE (T) IN COLLISIONS OF LIGHT NUCLEI AT S(NN)**(1/2) = 31.5-GEV

The AXIAL FIELD SPECTROMETER collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 231 (1989) 359-364, 1989.
Inspire Record 287781 DOI 10.17182/hepdata.29771

Calorimeter measurements of dσ de t for pp, dd, pα , and αα collisions at S nn =31.5 GeV are presented for the pseudorapidity interval | η cm | ⩽ 0.7, extending over eight decades to E t ⩾ 30 GeV. The data are compared with models that predict nuclear cross sections directly from pp data, under the assumption of independent nucleon scatters.

1 data table

The distributions are fitted D(SIG)/D(ET)=CONST*ET**POWER*EXP(-SLOPE*ET).


The Cross-Section for the Production of Massive electron Pairs and the Upsilon (9.5-GeV) in Proton Proton Collisions at the CERN ISR

Cobb, J.H. ; Iwata, S. ; Palmer, R.B. ; et al.
Phys.Lett.B 72 (1977) 273-277, 1977.
Inspire Record 122577 DOI 10.17182/hepdata.27504

Measurements of the cross section for the production of electron pairs with invariant masses between 4 and 8.7 GeV are presented as a function of the centre-of-mass energy ( s = 28 to s = 62 GeV ) of the colliding proton beams. A significant excess of events is observed in the region 8.7 to 10.3 GeV; these are ascribed to the ϒ(9.5 GeV) resonances and estimates of the production cross sections are given.

2 data tables

Axis error includes +- 40/40 contribution (Due to the uncertainty in efficiency).

Axis error includes +- 40/40 contribution (Due to the uncertainty in efficiency).


Study of Massive Electron Pair Production at the {CERN} Intersecting Storage Rings

Kourkoumelis, C. ; Resvanis, L.K. ; Filippas, T.A. ; et al.
Phys.Lett.B 91 (1980) 475-480, 1980.
Inspire Record 152742 DOI 10.17182/hepdata.27237

Data from a study of electron pairs produced in pp collisions (√ s = 5 and 63 GeV) are used to extend measurements of the scaling function down to m /√ s ≈ 0.07 (4.5 < m < 19 GeV). The dilepton continuum can be described by the scaling formula (fx475-1)

2 data tables

No description provided.

No description provided.


A Measurement of Direct Photon Production at Large P(T) at the {CERN} {ISR}

Diakonou, M. ; Kourkoumelis, C. ; Resvanis, L.K. ; et al.
Phys.Lett.B 91 (1980) 296-300, 1980.
Inspire Record 152520 DOI 10.17182/hepdata.27234

We have measured direct photon production in pp collisions at the CERN intersecting storage rings for c.m. energies 31 < √ s < 63 GeV and transverse momenta up to 9GeV/ c , using segmented lead/liquid-argon calorimeters. The ratio of direct photon to π 0 production is significantly larger than zero, starting at p T ≈ 4 GeV/ c and increasing to values of about 0.4 at 9GeV/ c . No significant √s dependence is seen.

1 data table

No description provided.


Characteristics of J/$\psi$ and $\Upsilon$ production at the {CERN} intersecting storage rings

Kourkoumelis, C. ; Resvanis, L. ; Filippas, T.A. ; et al.
Phys.Lett.B 91 (1980) 481-486, 1980.
Inspire Record 152744 DOI 10.17182/hepdata.27235

We present the B( d θ d y ) y=0 for J /ψ over thefull range of ISR energies and for ϒ at √ s = 53 and 63 GeV, using their dielectron decay mode. The average transverse momentum and the decay angles are presented. We found ( p T ) = 1.75 ± 0.19 GeV for ϒ, being higher than ( p T ) of the continuum and rising with √s. We present a comparison of the cross sections of J/ψ and ϒ with those of the continuum, at the same masses, as a function of √s. An appropriate scaling of the hadronic production of quark-antiquark narrow bound states involving ⋉, J/ψ, ψ′, ϒ, and ϒ′ is presented as a function of m /√ s at y = 0, and is compared with Drell-Yan scaling.

2 data tables

No description provided.

UPSILON HERE = UPSILON+UPSILON PRIME.


Inclusive $\pi^0$ Production at Very Large $p_T$ at the {ISR}

Kourkoumelis, C. ; Resvanis, L.K. ; Filippas, T.A. ; et al.
Phys.Lett.B 84 (1979) 271-276, 1979.
Inspire Record 141135 DOI 10.17182/hepdata.27343

Inclusive π 0 production at 90° has been studied at the ISR at s 1 2 = 52.7 and 62.4 GeV over the p T range from 7 to 15 GeV/ c . The two photons from π 0 decay yielded overlapping electromagnetic showers in the liquid-argon-Pb plate calorimeter detector system. Any direct photon production is included in these measurements. For large values of p T , the cross section is observed to decrease with p T more slowly than the p T −8 behaviour which has been observed at lower values of p T .

1 data table

No description provided.


Inclusive $\eta$ Production at High $p_T$ at the {ISR}

Kourkoumelis, C. ; Resvanis, L.K. ; Filippas, T.A. ; et al.
Phys.Lett.B 84 (1979) 277-280, 1979.
Inspire Record 141136 DOI 10.17182/hepdata.27350

The inclusive η production cross section at the CERN ISR has been measured for p T values of up to 11 GeV/ c . We find that the η π 0 cross-section ratio has an average value of 0.55 ± 0.07 and varies little with p T .

1 data table

No description provided.


Direct Production of High $p_T$ Single Photons at the {CERN} Intersecting Storage Rings

The Athens-Athens-Brookhaven-CERN collaboration Diakonou, M. ; Kourkoumelis, C. ; Resvanis, L.K. ; et al.
Phys.Lett.B 87 (1979) 292-296, 1979.
Inspire Record 143254 DOI 10.17182/hepdata.27293

Single photon production in pp collisions at 30 < √ s < 62 GeV has been measured with liquid-argon-lead calorimeters at the CERN ISR. This process remains approximately constant with increasing √ s . For fixed √ s , the single photon to π 0 ratio increases strongly with increase in p T . The γ π 0 ratio is about 0.2 for p T above 4.5 GeV/c.

1 data table

No description provided.


Study of Resolved High {P(T)} Neutral Pions at the {CERN} {ISR}

Kourkoumelis, C. ; Resvanis, L.K. ; Voulgaris, G. ; et al.
Phys.Lett.B 83 (1979) 257-260, 1979.
Inspire Record 140588 DOI 10.17182/hepdata.27353

The inclusive production of π 0 at large values of p T in pp collisions at the ISR has been studied. In this experiment the two photons are resolved and separately measured for p T values of up to 6 GeV/ c , giving confidence that the desired signal has been separated from various backgrounds.

1 data table

No description provided.