Measurements of μμ pairs from open heavy flavor and Drell-Yan in p+p collisions at s=200 

Abstract

PHENIX reports differential cross sections of μμ pairs from semileptonic heavy-flavor decays and the Drell-Yan production mechanism measured in p þ p collisions at ffiffi ffi s p ¼ 200 GeV at forward and backward rapidity (1.2 < jηj < 2.2). The μμ pairs from cc, bb, and Drell-Yan are separated using a template fit to unlike-and like-sign muon pair spectra in mass and p T. The azimuthal opening angle correlation between the muons from cc and bb decays and the pair-p T distributions are compared to distributions generated using PYTHIA and POWHEG models, which both include next-to-leading order processes. The measured distributions for pairs from cc are consistent with PYTHIA calculations. The cc data present narrower azimuthal correlations and softer p T distributions compared to distributions generated from POWHEG. The bb data are well described by both models. The extrapolated total cross section for bottom production is 3.75 AE 0.24ðstatÞ AE 0.35 0.50 ðsystÞ AE 0.45ðglobalÞ ½μb, which is consistent with previous measurements at the Relativistic Heavy Ion Collider in the same system at the same collision energy and is approximately a factor of 2 higher than the central value calculated with theoretical models. The measured Drell-Yan cross section is in good agreement with next-to-leading-order quantumchromodynamics calculations.

Nuclear-modification factor of charged hadrons at forward and backward rapidity in p + Al and p +

“…A detailed description of the three models and a previous study for muons can be found in Refs. [49,50]. The variation of the combined acceptance and efficiency for π ± and K ± between the three models is less than 2% in p T and η.…”

Pion-induced Drell-Yan processes within TMD factorization

“…In the TMD regime the same effect has been observed in [1] (for the same experiments that are considered in [21]), namely, about 40% deficit in the normalization that decreases with the increase of energy (see table 3 in [1]). Note, both analyses [21] and [1] have not a problem with the description of PHENIX data [47] that have a similar range of Q but measured in the collider regime. A similar problem was also observed in semi-inclusive deep-inelastic scattering (SIDIS) [48].…”

Measurement ofJ/ψat forward and backward rapidity inp+p,p+Al,Acharya1, Adare2, Aidala3 et al. 2020Phys. Rev. CSelf Cite

“…The mass spectra contain muon pairs from J/ψ decays, as well as significant contributions from combinations of real muons not from a J/ψ, as well as misidentified hadrons. Details about the dimuon selection to reduce the background contributions are described in [40,41].…”