Aliev, Malik
DSIG/DYRAP
Max results
Sort by Reverse order

Showing 3 of 63 results

Measurement of high-p(T) single electrons from heavy-flavor decays in p + p collisions at s**(1/2) = 200-GeV.

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 97 (2006) 252002, 2006.
Inspire Record 725484 DOI 10.17182/hepdata.57283

The momentum distribution of electrons from decays of heavy flavor (charm and beauty) for midrapidity |y| < 0.35 in p+p collisions at sqrt(s) = 200 GeV has been measured by the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) over the transverse momentum range 0.3 < p_T < 9 GeV/c. Two independent methods have been used to determine the heavy flavor yields, and the results are in good agreement with each other. A fixed-order-plus-next-to-leading-log pQCD calculation agrees with the data within the theoretical and experimental uncertainties, with the data/theory ratio of 1.72 +/- 0.02^stat +/- 0.19^sys for 0.3 < p_T < 9 GeV/c. The total charm production cross section at this energy has also been deduced to be sigma_(c c^bar) = 567 +/- 57^stat +/- 224^sys micro barns.

3 data tables
Table 1

Heavy-flavor decay electrons invariant differential cross-section An additional 10% normalization uncertainty is to add.

Table 2

Differential charm cross section To obtain this value, the differential "charm-decay" electrons cross-section, integrated over PT>0.4 GeV/c, has been extrapolated down to PT=0 using the spectrum shape predicted by a fixed-order-plus-next-to-leading-log (FONLL)calculation. The contribution from beauty and beauty cascades, estimated to be 0.1 microbarn, has been substracted, and the c->e branching ratio used was 9.5 +- 1.0%.

Table 3

Total charm cross section To obtain the total charm cross section, the differential charm cross section has been extrapolated to the whole rapidity range, using a HVQMNR rapidity distribution with aCTEQ5M PDF.


Measurement of inclusive differential cross sections for Upsilon(1S) production in p anti-p collisions at s**(1/2) = 1.96-TeV

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 94 (2005) 232001, 2005.
Inspire Record 676877 DOI 10.17182/hepdata.51525

We present measurements of the inclusive production cross sections of the Upsilon(1S) bottomonium state in ppbar collisions at sqrt(s) = 1.96 TeV. Using the Upsilon(1S) to mu+mu- decay mode for a data sample of 159 +- 10 pb^-1 collected by the D0 detector at the Fermilab Tevatron collider, we determine the differential cross sections as a function of the Upsilon(1S) transverse momentum for three ranges of the Upsilon(1S) rapidity: 0 < |y| < 0.6, 0.6 < |y| < 1.2, and 1.2 < |y| < 1.8.

2 data tables
Table 1

Cross section per unit of rapidity times branching ratio to MU+ MU-. Systematic (DSYS) error does not include the 6.1 PCT uncertainty on the luminosity.

Table 2

Normalized differential cross section for UPSI(1S) production.. Errors contain statistical and systematics (excluding luminosity error).


QCD studies with e+ e- annihilation data at 130-GeV and 136-GeV.

The OPAL collaboration Alexander, G. ; Allison, John ; Altekamp, N. ; et al.
Z.Phys.C 72 (1996) 191-206, 1996.
Inspire Record 418007 DOI 10.17182/hepdata.47564

We have studied hadronic events produced at LEP at centre-of-mass energies of 130 and 136 GeV. Distributions of event shape observables, jet rates, momentum spectra and multiplicities are presented and compared to the predictions of several Monte Carlo models and analytic QCD calculations. From fits of event shape and jet rate distributions to\({\mathcal{O}}(\alpha _s^2 ) + NLLA\) QCD calculations, we determineαs(133 GeV)=0.110±0.005(stat.)±0.009(syst.). We measure the mean charged particle multiplicity 〈nch〉=23.40±0.45(stat.) ±0.47(syst.) and the position ζ0 of the peak in the ζp = ln(1/xp) distribution ζ0=3.94±0.05(stat.)±0.11(syst.). These results are compared to lower energy data and to analytic QCD or Monte Carlo predictions for their energy evolution.

23 data tables
Table 1

Determination of alpha_s.

Table 2

Multiplicity and high moments.

Table 3

Tmajor distribution.

More…