Adriani, O.
Max results
Sort by Reverse order

Showing 10 of 2763 results

Date

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
Table 1

Errors are combined statistical and systematic.

Table 2

Errors are combined statistical and systematic.

Table 3

Errors are combined statistical and systematic.


rivet Analysis
Measurements of $\alpha^- s$ in $e^+ e^-$ Annihilation at $\sqrt{s}=53$.3-{GeV} and 59.5-{GeV}

The TOPAZ collaboration Adachi, I. ; Aihara, H. ; Doser, M. ; et al.
Phys.Lett.B 227 (1989) 495-500, 1989.
Inspire Record 279575 DOI 10.17182/hepdata.29800

We studied the energy-energy correlation (EEC) and its asymmetry (AEEC) using e + e − hadronic annihilation events obtained at √ s =53.3 GeV and 59.5 GeV with the TOPAZ detector at the TRISTAN collider. We used a Monte Carlo simulation combined with the QCD matrix elements by Gottschalk and Shatz and the Lund string fragmentation model. By comparing the experimental data with simulated events, we determined the strong coupling constant α s at both energies. The results are 0.129±0.007 (stat) ±0.010 (syst) at √ s =53.3 GeV and 0.122±0.008 (stat) ±0.010 (syst) at 59.5 GeV.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Evidence for New States Produced in the Central Region in the Reaction $p p \to p$(f) ($\pi^+ \pi^- \pi^+ \pi^-$) $p(s$) at 300-{GeV}/$c$

The WA76 collaboration Armstrong, T.A. ; Benayoun, Maurice ; Beusch, W. ; et al.
Phys.Lett.B 228 (1989) 536-542, 1989.
Inspire Record 280165 DOI 10.17182/hepdata.29783

The reaction pp→p f ( π + π − π + π − )p s , where the π + π − π + π − system is centrally produced, has been studied at 300 GeV/ c in an experiment designed to search for gluonic states. The π + π − π + π − mass spectrum shows evidence for the f 1 (1285) with a mass of 1281±1 MeV and a width of 31±5 MeV. In addition there is evidence for two new enhancements at masses of 1449±4 and 1901±13 MeV with widths of 78±18 and 312±61 MeV respectively. An analysis of the state at 1.45 GeV indicates that it is not a π + π − π + π − decay mode of the f 1 (1420) or ι η(1440) .

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Observation of Centrally Produced $\theta$ / F2 (1720) in the Reaction $p p \to p$(f) ($K \bar{K}$) $p(s$) at 300-{GeV}/$c$

The WA76 collaboration Armstrong, T.A. ; Benayoun, Maurice ; Beusch, W. ; et al.
Phys.Lett.B 227 (1989) 186-190, 1989.
Inspire Record 279351 DOI 10.17182/hepdata.29801

The K + K − and K S 0 K S 0 systems centrally produced in the reaction pp→p f K K p s have been studied at 300 GeV/ c incident momentum. Both the K + K − and the K S 0 K S 0 mass spectra show large resonant production. For the first time in hadron collisions, clear evidence is found for the θ f 2 (1720) with parameters m =1713±10 MeV, Γ =181±30 MeV for the K + K − decay mode and m =1706±10 MeV, Γ =104±30 MeV for the K S 0 K S 0 decay mode. A spin analysis of the K + K − spectrum shows that for the θ f 2 (1720) J P =2 + is strongly favoured while 0 + and 1 − are excluded.

2 data tables
Table 1

Density matrix elements contributing in the fits of angular distributions in the F2PRIME(1525) region.

Table 2

Density matrix elements contributing in the fits of angular distributions in the F2(1720) region.


Production of $\rho^+$, $\rho^-$, $\rho^0$ (770), $\eta$ (550), $\omega(783)$ and F2 (1270) Mesons in Anti-nucleon Neon and Neutrino Neon Charged Current Interactions

The BEBC WA59 collaboration Wittek, W. ; Aderholz, M. ; Allport, P. ; et al.
Z.Phys.C 44 (1989) 175, 1989.
Inspire Record 278996 DOI 10.17182/hepdata.15079

The production of the meson resonances ϱ(770) (all three charge states), η(550), ω(783) andf2(1270) in\(\bar v\) Ne and ν Ne charged current interactions is investigated in a bubble chamber experiment with BEBC at CERN. Except for thef2, the main features of resonance production are reasonably well described by the Lund model, although the average resonance multiplicities are overestimated by the model by (67±30)%. The average multiplicities of all resonances, including thef2, are well reproduced by a semiempirical model, whose parameters were determined from hadron interaction data.

21 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

EXCLUSIVE MEASUREMENTS OF LIGHT FRAGMENT PRODUCTION AT FORWARD ANGLES IN Ne - Pb AND Ne - NaF COLLISIONS AT E/A = 400-MeV AND 800-MeV

Bastid, N. ; Alard, J.P. ; Arnold, J. ; et al.
Nucl.Phys.A 506 (1990) 637-654, 1990.
Inspire Record 25478 DOI 10.17182/hepdata.36887

Emission of light fragments at small angles is studied in relativistic heavy ion collisions using the Diogene plastic wall for both symmetrical and non-symmetrical target-projectile systems with 400 MeV per nucleon and 800 MeV per nucleon incident neon nuclei. Efficiency of multiplicity measurements in the small angle range for the selection of central or peripheral collisions is confirmed for asymmetric systems. Differential production cross sections of Z = 1 fragments show evidence for the existence of two emitting sources. The apparent temperature of each source is obtained from comparison with a thermodynamical model.

2 data tables
Table 1

THE NUCLEUS IS NAF. CHARGED PARTICLES IN THE CENTRAL DRIFT CHAMBER OF THE DIOGENE DETECTOR.

Table 2

THE NUCLEUS IS NAF. CHARGED PARTICLES IN THE CENTRAL DRIFT CHAMBER OF THE DIOGENE DETECTOR. THE EVENT SELECTION:A HEAVY FRAGMENT(Z>=6) IS REGISTRED IN THE PLASTIC WALL OF THE DIOGENE.


EXCLUSIVE PRODUCTION OF p anti-p pi+ pi- IN PHOTON-PHOTON COLLISIONS

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 40 (1989) 2772, 1989.
Inspire Record 279349 DOI 10.17182/hepdata.23017

We report a measurement of the e+e−→e+e−pp¯π+π− process with the TPC/Two-Gamma facility at the PEP e+e− storage ring at SLAC. Forty-five pp¯π+π− events were identified in data corresponding to an integrated e+e− luminosity of 142 pb−1. The cross section for γγ→pp¯π+π− is given both as a function of the γγ center-of-mass energy Wγγ, with Wγγ between 2.5 and 5.5 GeV, and as a function of the in variant mass squared q2 of one of the photons, with −q2<7 GeV2. This cross section falls much less rapidly with Wγγ than does the cross section for a similar process, γγ→pp¯. No Δ0Δ¯0 production is observed, and only a small fraction of the events at low Wγγ is consistent with γγ→Δ++Δ¯−−, Δ++p¯π−, or Δ¯−−pπ+. In an expanded search through the same data, four events compatible with either ΛΛ¯(Λ→pπ−) or Σ0Λ¯(Σ0→Λγ) production were found.

2 data tables
Table 1

Statistical errors only.

Table 2

Data read from graph.


$\tau$ Production and Decay With the Cello Detector at {PETRA}

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Dainton, J.B. ; et al.
Phys.Lett.B 222 (1989) 163-172, 1989.
Inspire Record 276859 DOI 10.17182/hepdata.29824

The reaction e + e − → τ + τ − has been studied at centre of mass energies between 14.0 and 46.8 GeV with the CELLO detector at the PETRA e + e − collider. We present results for the cross section σ τ and the charge asymmetry A τ . The results are in good agreement with the standard model. We have also measured the topological decay rates BR 1 , BR 3 and BR 5 for the inclusive decay of the τ lepton into one, three and five charge particles. The results confirm and improve earlier CELLO measurements at other energies. We find for the combined values at all energies BR 1 = (84.9 ± 0.4 ± 0.3)%, BR 3 = (15.0 ± 0.4 ± 0.3)% and BR 5 = (0.16 ± 0.13 ± 0.04)%.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Corrected for radiative effects and background contributions.


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
Table 1

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


Observation of Double $\phi$ Meson Production in the Central Region for the Reaction $p p \to p$(f) ($K^+ K^- K^+ K^-$) $p(s$) at 300-{GeV}/$c$

The WA76 collaboration Armstrong, T.A. ; Benayoun, Maurice ; Beusch, W. ; et al.
Phys.Lett.B 221 (1989) 221-226, 1989.
Inspire Record 276743 DOI 10.17182/hepdata.29825

The reaction pp→p f (K + K − K + K − )p s in which the K + K − K + K − system is centrally produced has been studied at 300 GeV/ c . φφ production has been observed and the ratio σ (φK + K − )/ σ ( φφ ) is 1.0±0.3. The cross section for central production of φφ is found to be the same at 300 GeV/ c and 85 GeV/ c . An angular analysis of the φφ system favours J P =2 + over 0 − .

1 data table
Table 1

No description provided.