arXiv subjects

G. Rakness

Publications and source records attributed to G. Rakness.

7 recordsLinked to original sources

arXiv2023

Workshop on a future muon program at FNAL

The Snowmass report on rare processes and precision measurements recommended Mu2e-II and a next generation muon facility at Fermilab (Advanced Muon Facility) as priorities for the frontier. The Workshop on a future muon program at FNAL was held in March 2023 to discuss design studies for Mu2e-II, organizing efforts for the next generation muon facility, and identify synergies with other efforts (e.g., muon collider). Topics included high-power targetry, status of R&D for Mu2e-II, development of compressor rings, FFA and concepts for muon experiments (conversion, decays, muonium and other opportunities) at AMF. This document summarizes the workshop discussions with a focus on future R&D tasks needed to realize these concepts.

hep-ex↗

arXiv2022

Mu2e-II: Muon to electron conversion with PIP-II

An observation of Charged Lepton Flavor Violation (CLFV) would be unambiguous evidence for physics beyond the Standard Model. The Mu2e and COMET experiments, under construction, are designed to push the sensitivity to CLFV in the mu to e conversion process to unprecedented levels. Whether conversion is observed or not, there is a strong case to be made for further improving sensitivity, or for examining the process on additional target materials. Mu2e-II is a proposed upgrade to Mu2e, with at least an additional order of magnitude in sensitivity to the conversion rate over Mu2e. The approach and challenges for this proposal are summarized. Mu2e-II may be regarded as the next logical step in a continued high-intensity muon program at FNAL.

hep-ex↗

arXiv2005

Neutral Pion Suppression at Forward Rapidities in d+Au Collisions at STAR

Measurements of the inclusive yields of pi0 mesons in p+p and d+Au collisions at center of mass energy sqrt(s_NN)=200 GeV and pseudorapidity =4.00 (d beam direction) are reported. The yield for p+p collisions is in general agreement with perturbative QCD calculations. The d+Au yield is in agreement with a calculation which models the Au nucleus as a Color Glass Condensate for forward particle production. The nuclear modification factor derived from the inclusive yields is qualitatively consistent with models which suppress the gluon density in nuclei.

hep-ex↗

arXiv2005

Forward Pion Production in p+p and d+Au Collisions at STAR

Measurements are reported of the production of high energy pi-zero mesons from the STAR experiment in p+p and d+Au collisions at sqrt(s_NN)=200 GeV and =4.00 (d beam direction). The inclusive yield agrees with perturbative QCD calculations in p+p collisions, but is found to be reduced in d+Au collisions. The azimuthal correlations of the forward pi-zero with charged hadrons at midrapidity agree with PYTHIA in p+p collisions, but are suppressed in d+Au collisions. The results are consistent with the conjecture that the gluon density in nuclei is suppressed.

hep-ex↗

arXiv2005

Future of low-x forward physics at RHIC

The rapidity dependence of inclusive and coincident particle production in d(p)+Au collisions at RHIC can be used to probe nuclear parton distribution functions down to small momentum fractions where theory anticipates that parton saturation could be present. This paper describes how such experiments could be completed.

hep-ex↗

arXiv2005

Forward Pion Production in Hadron Collisions at STAR

Measurements are reported of the production of high energy pi^0 mesons at large pseudorapidity, coincident with charged hadrons at mid-rapidity, for proton+proton and deuteron+gold collisions at sqrt{s_{NN}}=200 GeV. The p+p cross section for inclusive pi^0 production follows expectations from next-to-leading order perturbative QCD. A suppression of the back-to-back azimuthal correlations was observed in d+Au, qualitatively consistent with the gluon saturation picture. Experimental uncertainties regarding the inclusive measurement are discussed.

nucl-ex↗

arXiv2002

Analyzing Powers for Forward p+p->pi0+X at STAR

Preliminary results of the analyzing power for the production of forward, high-energy pi0 mesons from collisions of transversely polarized protons at sqrt(s)=200 GeV from STAR are presented. The kinematic ranges covered by the data are x_F=0.2-0.6 and p_T=1-3 GeV/c. The analyzing power at sqrt(s)=200 GeV is found to be comparable to that observed at sqrt(s)=20 GeV.

hep-ex↗