Bebek, C.
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A High Statistics Measurement of the Nucleon Structure Function F(2) (X,$Q^2$) From Deep Inelastic Muon - Carbon Scattering at High $Q^2$

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.
Phys.Lett.B 195 (1987) 91-96, 1987.
Inspire Record 247013 DOI 10.17182/hepdata.30107

We present results from a high statistics study of the nucleon structure function F 2 ( x , Q 2 ) measured in deep inelastic scattering of muons on carbon in the kinematic range 0.25⩽ x ⩽0.80 and Q 2 ⩾25 GeV 2 . The analysis is based on 1.5×10 6 reconstructed events recorded at beam energies of 120, 200 and 280 GeV. R = σ L / σ T is found to be independent of x in the range 0.25⩽ x ⩽0.07 and 40 GeV 2 ⩽ Q 2 ⩽200 GeV 2 with a mean value R =0.015±0.013 ( stat ) ±0.026 (syst.).

19 data tables
Table 1

R=SIG(L)/SIG(T).

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Production of $\rho^0$ and F2 Mesons in $\pi^- p$ Interactions at 360-{GeV}/$c$

The LEBC-EHS collaboration Bailly, J.L. ; Banerjee, S. ; Castelli, E. ; et al.
Z.Phys.C 36 (1987) 545, 1987.
Inspire Record 247583 DOI 10.17182/hepdata.15699

We report on a study ofρ0 andf2 inclusive production in π−−p interactions at 360 GeV/c, using the LEBC-EHS set-up at CERN and reconstructing about 165000 events. Theρ0,f2 andρ30 cross sections are determined forxF>0,xF>0.4 andxF>0.6 respectively and theρ0 andf2 Feynman-x distributions and transverse momentum distributions are presented.

1 data table
Table 1

No description provided.


rivet Analysis
Observation of $\Omega^-$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

Klein, S. ; Himel, T. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 59 (1987) 2412, 1987.
Inspire Record 247900 DOI 10.17182/hepdata.20175

Inclusive Ω− production in e+e− annihilation at 29 GeV has been measured with the Mark II detector. From an integrated luminosity of 207 pb−1, we determine a production rate of 0.014±0.006±0.004 Ω−, Ω¯+ per hadronic event. This is roughly 35 times the Lund-model prediction of 0.0004 Ω−, Ω¯+ per hadronic event, but comparable to the Webber-model prediction of 0.006 Ω−, Ω¯+ per hadronic event. The large rate of Ω− production, compared with production rates for other baryons, and with theoretical predictions based on diquark models, indicates that spin suppression does not hold for Ω− production.

2 data tables
Table 1

Radiatively corrected inclusive cross section.

Table 2

Extrapolation to full momentum range.


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.


rivet Analysis
EXCLUSIVE PRODUCTION OF PROTON - ANTI-PROTON PAIRS IN TWO PHOTON COLLISIONS AT PEP

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 36 (1987) 3506, 1987.
Inspire Record 246557 DOI 10.17182/hepdata.23356

We report cross sections for the process γγ→pp¯ at center-of-mass energies W from 2.0 to 2.8 GeV. These results have been extracted from measurements of e+e−→e+e−pp¯ at an overall center-of-mass energy of 29 GeV, using the TPC/Two-Gamma facility at the SLAC storage ring PEP. Cross sections for the untagged mode [both photons nearly real] are shown to lie well above QCD predictions. Results are also presented for the single-tagged mode [one photon in the range 0.16<Q2<1.6 (GeV/c)2].

3 data tables
Table 1

Data read from graph in preprint. Statistical errors only.

Table 2

Data read from graph. Statistical errors only.

Table 3

Data read from graph. Statistical errors only.


rivet Analysis
First Observation of $\gamma \gamma \to \omega \rho^0$

The ARGUS collaboration Albrecht, H. ; Andam, A.A. ; Binder, U. ; et al.
Phys.Lett.B 196 (1987) 101, 1987.
Inspire Record 247567 DOI 10.17182/hepdata.30104

The reaction γγ → 2 π + 2 π − π 0 has been studied using the the ARGUS detector at the e + e − storage ring DORIS II at DESY. The production of the vector-meson pair ωϱ 0 is observed for the first time. The cross section for γγ → ωϱ 0 and the topological cross section for γγ → 2 π + 2 π − π 0 are given. The angular distribution in ωϱ 0 events do not indicate any specific dominant spin-parity; they are consistent with isotropic production and decay of the ω and ϱ 0 mesons over the available W γγ range.

2 data tables
Table 1

Topological cross section.

Table 2

OMEGA RHO0 Production cross section.


>A Measurement of the $\bar{p} p \to \pi^+ \pi^-$ Reaction for 158-{MeV}/$c \le p(\bar{p}) \le$ 275-{MeV}/$c$

Bardin, G. ; Burgun, G. ; Calabrese, R. ; et al.
Phys.Lett.B 192 (1987) 471-474, 1987.
Inspire Record 246571 DOI 10.17182/hepdata.30155

A measurement of the total cross section for the reaction p p → π + π − has been performed for seven values of the incident momentum between 158 and 275 MeV/ c . The values obtained, if compared with previous results at higher momenta, agree with a 1/ß dependence. The differential cross section sssumed over the whole incident momentum range has also been measured and the result of a fit by Legendre polynomials is given.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

4*PI*LEG(L=0,P=4) = 1.07 +- 0.13 mb.


rivet Analysis
UA5: A general study of proton-antiproton physics at s**(1/2) = 546-GeV

The UA5 collaboration Alner, G.J. ; Alpgard, K. ; Anderer, P. ; et al.
Phys.Rept. 154 (1987) 247-383, 1987.
Inspire Record 244829 DOI 10.17182/hepdata.19330

None

3 data tables
Table 1

Mean charged multiplicity for NSD events extrapolated to the full phase space.

Table 2

Charged particle pseudorapidity density for NSD events at pseudorapidiy = 0.

Table 3

Corrected charged particle multiplicity distribution for NSD events.


Nuclear Effects on the Nucleon Structure Functions in Hadronic High Mass Dimuon Production

The NA10 collaboration Bordalo, P. ; Busson, P. ; Kluberg, L. ; et al.
Phys.Lett.B 193 (1987) 368, 1987.
Inspire Record 245533 DOI 10.17182/hepdata.30122

We compare the differential cross sections of high-mass muon pair production on deuterium and tungsten by incident negative pions of 140 and 286 GeV. We find an indication of a nuclear effect on the nucleon quark distributions comparable in magnitude to what is observed in muon-iron deep inelastic scattering, whereas the pion-quark distribution is unaffected, compatibly with QCD factorization.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Production of W's wiith Large Transverse Momentum at the CERN Proton - Antiproton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Phys.Lett.B 193 (1987) 389-398, 1987.
Inspire Record 246169 DOI 10.17182/hepdata.30164

We have measured the W transverse momentum distribution ( p T W ) using a sample of 323 W → eν and W → μν events produced in proton-antiproton collisions at the CERN collider. In the present letter we extend the study of the distribution up to p T W ∼- m W and compare to leading and higher order QCD. This comparison is a precise test of QCD with hadron colliders and the inclusive spectrum gives good agreement over a large range of p T W . However we observed two events at very large p T W (∼- 100 GeV/ c ) in which the W candidate recoils against an energetic di-jet system. Both events have a very large missing transverse energy and a jet-jet mass compatible with the W mass. In a separate analysis, a topologically similar event has been observed in which a high-mass di-jet system is balanced by a large missing transverse energy which could be interpreted as Z 0 → ν ν decay. We cannot easily explain these three events in terms of explicit second-order QCD calculations. However we cannot exclude at this stage the possibility that they are the result of non-gaussian fluctuations in the response of UA1 calorimetry or a statistical fluctuation in the data.

1 data table
Table 1

THESE NUMBERS WRE READ OFF FIG 1A.