Baldini, A.
DN/DZ
Max results
Sort by Reverse order

Showing 6 of 26 results

Date

rivet Analysis
Inclusive $\phi$ Meson Production in Electron - Positron Interactions in the Energy Region of the $\Upsilon$ Resonances

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Z.Phys.C 41 (1989) 557, 1989.
Inspire Record 262551 DOI 10.17182/hepdata.15528

We report on a high precision measurement of ϕ-meson production in continuum events and in direct decays of the Υ(1S)- and Υ(2S)-mesons. The ratio of the total production rate of ϕ-mesons in direct Υ(1S)- and Υ(2S)-decays over that in continuum events is 1.32±0.08±0.09 and 1.07±0.13±0.11 respectively. This is compatible with the corresponding ratio obtained for lighter mesons, but is appreciably smaller than the relative baryon production rate.

6 data tables
Table 1

PHI meson cross section on the continuum.

Table 2

Differential particle density for PHI mesons in decays of upsilon(1S) and upsilon(2S).

Table 3

No description provided.

More…

Evidence for Anomalous Prompt Photons in Deep Inelastic Muon Scattering at 200-{GeV}

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 218 (1989) 248-256, 1989.
Inspire Record 261250 DOI 10.17182/hepdata.29855

The inclusive yield of photons has been measured from deep inelastic interactions of 200 GeV muons on hydrogen. After subtracting the contributions from hadron electromagnetic decays and Bethe-Heitler muon bremsstrahlung, residual photons are observed at low p T and low z at a mean level of 0.15±0.06 per interaction. The quark Compton scattering process is unable to explain the data, thus indicating an anomalous photon production.

2 data tables
Table 1

Z distribution of anomalous direct photons.

Table 2

PT distribution of anomalous direct photons.


Analysis of the Fragmentation Properties of Quark and Gluon Jets at the CERN SPS $p \bar{p}$ Collider

The UA1 collaboration Arnison, G. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Nucl.Phys.B 276 (1986) 253-271, 1986.
Inspire Record 229898 DOI 10.17182/hepdata.33618

A sample of two-jet events from the UA1 experiment at the CERN $p \bar{p}$ Collider has been used to study the fragmentation of high-energy quark and gluon jets into charged hadrons. Compared with lower-energy jets observed in $e^+ e^−$ and $pp$ collisions, the fragmentation function measured in the present experiment is softer (i.e. peaked to smaller values of z) and the mean internal transverse momentum is larger, mainly because of the effects of the QCD scaling violations. Using our knowledge of the quark and gluon structure functions in the proton, together with the QCD matrix elements, a statistical separation of quark and gluon jets is achieved within the present experiment. The fragmentation function for the gluon jets is found to be softer, and the angular spread of the fragmentation products larger, than is the case for quark jets.

1 data table
Table 1

No description provided.


A DETERMINATION OF THE FRAGMENTATION FUNCTIONS OF u QUARKS INTO CHARGED PIONS

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 160 (1985) 417-420, 1985.
Inspire Record 213987 DOI 10.17182/hepdata.49627

The fragmentation functions of u-quarks into positive and negative pions are determined from an analysis of identified pions produced in deep inelastic muon-deuterium scattering. The method adopted is not sensitive to the knowledge of the primary quark distribution functions. The fragmentation of u quarks to positive pions is found to fall less steeply in z than that to negative pions as expected in the quark parton model.

1 data table
Table 1

Here Z=P(P=3)/E(P=3).


$D^{*\pm}$ Production in Jets at the {CERN} {SPS} Collider

The UA1 collaboration Arnison, G. ; Allkofer, O.C. ; Astbury, A. ; et al.
Phys.Lett.B 147 (1984) 222-226, 1984.
Inspire Record 203147 DOI 10.17182/hepdata.30497

We report evidence for the production of the charged D ∗ mesons in pp̄ collisions at s = 540 GeV . The search was confined to the charged particle fragments of hadronic jets, which are expected to be predominantly gluon jets in this experiment. The fragmentation function and production rate for D ∗ in jets of average transverse momentum of 28 GeV/ c are given.

1 data table
Table 1

THE D*'S ARE CONSIDERED AS ARISING ONLY FROM FRAGMENTATION OF HADRONIC JETS ('GLUON' JETS). HERE THE <PT> OF THE JET IS AROUND 28 GEV THE DEFINITION OF Z IS P(D*).P(JET)/(P(JET))**2.


FRAGMENTATION IN NEUTRINO AND ANTI-NEUTRINOS CHARGED CURRENT INTERACTIONS ON PROTON AND NEUTRON

The AMSTERDAM-BERGEN-BOLOGNA-PADUA-PISA-SACLAY-TURIN collaboration Allasia, D. ; Angelini, C. ; Baldini, A. ; et al.
Z.Phys.C 24 (1984) 119-131, 1984.
Inspire Record 207322 DOI 10.17182/hepdata.16217

Some experimental properties of the charged hadronic fragments are compared for νp, νn,\(\bar vp\) and\(\bar vn\) interactions: multiplicities of forward and backward going particles,xF distributions for pions, fragmentation functions and theirQ2 andW2 dependence. The results are compared with the predictions of the Lund fragmentation model.

1 data table
Table 1

No description provided.