Kourkoumelis, C.
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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
Table 1

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

Table 2

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
Table 1

No description provided.

Table 2

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
Table 1

No description provided.

Table 2

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
Table 1

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
Table 1

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
Table 1

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
Table 1

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
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


High p(t) Direct Photon Production in p p Collisions

Anassontzis, E. ; Karabarbounis, A. ; Kourkoumelis, C. ; et al.
Z.Phys.C 13 (1982) 277-289, 1982.
Inspire Record 176956 DOI 10.17182/hepdata.16410

Direct photon and neutral-pion production have been measured inpp collisions at the CERN ISR for 30<\(\sqrt s \)<63 GeV and transverse momenta up to 12 GeV/c. The direct photon signal relative to neutral-pion production increases withpT and shows little\(\sqrt s \)-dependence. Results are reported from a variety of running conditions, and details are given on the method of analysis and on the evaluation of systematic errors for the inclusive cross-section of single-photon and neutral-pion production.

0 data tables

A Study of the Production of High $p$(t) $\pi^0$'s at the {CERN} Intersecting Storage Rings

Kourkoumelis, C. ; Resvanis, L.K. ; Filippas, T.A. ; et al.
Z.Phys.C 5 (1980) 95-104, 1980.
Inspire Record 152946 DOI 10.17182/hepdata.16617

The inclusive cross-section for π0 production near 90° inpp collisions at the CERN Intersecting Storage Rings has been studied for thepT range 3<pT<16GeV/c at four different centre-of-mass energies (\(\sqrt s = 30.6\), 44.8, 52.7, and 62.8 GeV). In this experiment the two photons from the π0→yy decay were resolved and measured separately forpT values up to 10 GeV/c. Results indicate an agreement with thepT−8 behaviour for the lower values ofpT and a slower decrease of the cross-section for the higher values ofpT. The high-pT data deviate from the scaling expressionpT−nF(xT), which holds for the lowerpT values (pT<8GeV/c).

4 data tables
Table 1

USING RETRACTED GEOMETRY.

Table 2

USING SUPER-RETRACTED GEOMETRY.

Table 3

USING SUPER-RETRACTED GEOMETRY.

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