Qian, X.
Max results
Sort by Reverse order

Showing 10 of 2615 results

Date

rivet Analysis
INCLUSIVE gamma AND pi0 PRODUCTION CROSS-SECTIONS AND ENERGY FRACTIONS IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Bakken, J.A. ; et al.
Z.Phys.C 27 (1985) 187, 1985.
Inspire Record 205868 DOI 10.17182/hepdata.16101

Inclusive production cross sections for photons and π0's ine+e− annihilation at a center of mass energy of 29 GeV have been measured. The π0 production spectrum agrees with a corresponding measurement for π±. The ratio of the π0 inclusive rate to the average for π± is 0.92±0.14. The fractions of the total energy carried by photons and π0's are 0.244±0.016 and 0.217±0.033, respectively. The fraction of total energy carried by all stable hadrons, prompt leptons and photons is determined to be 0.938±0.045, leaving 0.062±0.045 for neutrinos.

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


Production of $\pi^0$ mesons in muon - hydrogen interactions at 200-GeV

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Z.Phys.C 18 (1983) 189, 1983.
Inspire Record 189283 DOI 10.17182/hepdata.16369

Thez andpT2 distributions of π0 mesons produced by the interaction of 200 GeV muons on hydrogen are presented. Comparisons are made with other π0 and charged hadron data and with the predictions of perturbative QCD. The data show a rise of 〈pT2〉 withW2 which is consistent with QCD, and withz2 which requires a contribution from a primordialkT. The fraction of total energy which appears as π0 mesons is 0.27±0.05.

1 data table match query
Table 1

No description provided.


$\rho^0$ and $\omega$ Production in Deep Inelastic $\mu p$ Interactions at 280-{GeV}/$c$

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Z.Phys.C 33 (1986) 167, 1986.
Inspire Record 231103 DOI 10.17182/hepdata.15815

Inclusive distributions of ρ0 and ω mesons have been measured in deep inelastic μ-p interactions at 280 GeV/c. A comparison of the ρ0 cross sections with other leptoproduction experiments is presented. The ω results represent the first observation of this inclusive channel in high energy leptoproduction. The ρ0 and ω yields are found to be equal as may be expected from the available density of states in isospin space. This contrasts with spin angular momentum where the vector to pseudoscalar meson ratio is suppressed relative to the available number of spin states.

4 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Jet Production and Fragmentation Properties in Deep Inelastic Muon Scattering

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Z.Phys.C 36 (1987) 527, 1987.
Inspire Record 247586 DOI 10.17182/hepdata.15717

None

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


Charm Production in Deep Inelastic Muon - Iron Interactions at 200-{GeV}/$c$

The European Muon collaboration Arneodo, M. ; Aubert, J.J. ; Bassompierre, G. ; et al.
Z.Phys.C 35 (1987) 1, 1987.
Inspire Record 230629 DOI 10.17182/hepdata.15765

Dimuon and trimuon events have been studied in deep inelastic muon scattering on an iron target at an incident muon energy of 200 GeV. The events are shown to originate mainly from charm production. Comparison of the measured cross sections with data taken at higher muon energies shows that charm production originates predominantly from transverse virtual photons. Within the framework of the photon gluon fusion model this indicates that the parity of the gluon is odd.

1 data table match query
Table 1

No description provided.


Transverse momentum of charged hadrons observed in deep inelastic muon scattering

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 95 (1980) 306, 1980.
Inspire Record 154081 DOI 10.17182/hepdata.27176

The transverse momenta of charged hadrons produced in high energy muon-proton scattering have been studied. The average squared transverse momentum 〈 p 2 ⊥ 〉 shows a strong dependence on z = E h / v characteristic of intrinsic momentum effects and a significant rise as a function of s = W 2 . The W 2 , q 2 , x and z dependences of the data are compared with the predictions of a perturbative QCD model.

4 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Event-by-event fluctuations of average transverse momentum in central Pb + Pb collisions at 158-GeV per nucleon.

The NA49 collaboration Appelshäuser, H. ; Bächler, J. ; Bailey, S.J. ; et al.
Phys.Lett.B 459 (1999) 679-686, 1999.
Inspire Record 498247 DOI 10.17182/hepdata.41648

We present first data on event-by-event fluctuations in the average transverse momentum of charged particles produced in Pb+Pb collisions at the CERN SPS. This measurement provides previously unavailable information allowing sensitive tests of microscopic and thermodynamic collision models and to search for fluctuations expected to occur in the vicinity of the predicted QCD phase transition. We find that the observed variance of the event-by-event average transverse momentum is consistent with independent particle production modified by the known two-particle correlations due to quantum statistics and final state interactions and folded with the resolution of the NA49 apparatus. For two specific models of non-statistical fluctuations in transverse momentum limits are derived in terms of fluctuation amplitude. We show that a significant part of the parameter space for a model of isospin fluctuations predicted as a consequence of chiral symmetry restoration in a non-equilibrium scenario is excluded by our measurement.

1 data table match query
Table 1

Studied YRAP (for PI's) is in a region of 4 TO 5.5.


A measurement of the photonuclear interactions of 180-GeV muons in iron

Alexa, C. ; Anderson, K. ; Antonaki, A. ; et al.
Eur.Phys.J.C 28 (2003) 297-304, 2003.
Inspire Record 621812 DOI 10.17182/hepdata.43173

The energy spectrum and the cross section of photonuclear interactions of 180 GeV muons in iron were measured at the CERN SPS using prototype modules of the ATLAS hadron calorimeter. The differential

2 data tables match query
Table 1

Measured differential cross section for fractional photonuclear muon energy loss.

Table 2

Total photonuclear cross section which gives best agreement of energy loss with theory. See text of paper for details.


Phi emission in central Pb + Pb collisions at 158-GeV/u.

The NA49 collaboration Pühlhofer, Falk ; Appelshäuser, H. ; Bächler, J. ; et al.
Nucl.Phys.A 638 (1998) 431-434, 1998.
Inspire Record 481889 DOI 10.17182/hepdata.36218

Data on φ -production obtained by the CERN NA49 experiment for central Pb+Pb collisions at 158 GeV/u are presented. Compared with pp interactions the φ -yield shows substantial strangeness enhancement: the φ /π ratio is found to increase by a factor of 2.6 ± 0.6, which is approximately the square of the K/π enhancement.

2 data tables match query
Table 1

5% most central collosions, MT - M0 = 0 - 1.4 GeV, preliminary data.

Table 2

5% most central events.


Hadron yields and hadron spectra from the NA49 experiment

The NA49 collaboration Jones, P.G. ; Afanasiev, S.V. ; Alber, T. ; et al.
Nucl.Phys.A 610 (1996) 188C-199C, 1996.
Inspire Record 432742 DOI 10.17182/hepdata.36468

Preliminary inclusive spectra of negative hadrons, net protons and neutral strange particles are presented, measured by the NA49 experiment in central Pb+Pb collisions at 158 GeV per nucleon. Comparison of their yields with those from the lighter S+S system suggests that the yields scale approximately with the number of participating nucleons.

4 data tables match query
Table 1

CENTRAL COLLISIONS, PRELIMINARY DATA.

Table 2

CENTRAL COLLISIONS, PRELIMINARY DATA.

Table 3

CENTRAL COLLISIONS, PRELIMINARY DATA.

More…