Heavy Flavor

Depending on the energy scale, there are two mechanisms that generate quark masses with different degrees of importance: current quark masses are generated by the electroweak symmetry breaking mechanism (Higgs mass) and spontaneous chiral symmetry breaking leads to the constituent quark masses in QCD (QCD mass). The QCD interaction strongly affects the light quarks (u, d, s) while the heavy quark masses (c, b, t) are mainly determined by the Higgs mechanism. In high-energy nuclear collisions at RHIC, heavy quarks are produced through gluon fusion and qq¯ annihilation. Heavy quark production is also sensitive to the parton distribution function. Unlike the light quarks, heavy quark masses are not modified by the surrounding QCD medium (or the excitations of the QCD medium) and the value of their masses is much higher than the initial excitation of the system. It is these differences between light and heavy quarks in a medium that make heavy quarks an ideal probe to study the properties of the hot and dense medium created in high-energy nuclear collisions.

 

Heavy flavor analyses at STAR can be separated into quarkonia, open heavy flavor and heavy flavor leptons.


 

First QA Plots for MTD

 

Upsilons in U+U, Warsaw regional meeting 2014

Efficiency studies, Raa and pT-spectrum.

Upsilons in U+U 193 GeV, status report

 Please find the attached slides

Upsilon 1S, 2S, 3S embedding QA

The full sample is ready. Please see the slides for the QA plots.

Alignment Update

Speaker : Michael Lomnitz


Talk time : 13:50, Duration : 00:20

 

Responses to Collaboration comments

PXL calibration

Speaker : Michael Lomnitz


Talk time : 13:30, Duration : 00:20

 

Upsilons in UU - Embedding QA and E/p

1. QA of available 1S embedding sample
2. Issue of dropping E/p means in real data

DNP_Abstract_Updated

 

Upsilon pp, dAu, AuAu GPC E-mail Responses

 This is a page to house long e-mail responses.

First look at Upsilons in Uranium

HF pwg 5/23/2013 notes:

1. Zoom on plots, peak area too tiny
2. Cluster energy on paired electron candidate

QA under new library of SL11d_embed

ry2009d and cone support material

Issue:

 This entry is to summarize the status of the ry2009a and ry2009d comparison. 

Upsilons in 2011 pp500 and an outlook for 2013

 We ran over the pp500 data from 2011 looking for upsilons.

HF Update, Trigger discussion for pp 500 GeV Run 13

 Update for HF Phone meeting regarding the discussion on the triggering on Upsilons for Run 13.
This is a summary of the email thread in the HF hypernews found here:

Presentations

 Page for uploading presentation drafts.

STAR Regional Meeting: Heavy Quark Production and Correlations 2012

2012-11-04
2012-11-06
Poland
-
from Monday, 5 November 2012 to Wednesday, 7 November 2012
Faculty of Physics, Warsaw University of Technology, Warsaw
Conference organizing committee information :
  • Jaroslav Bielcik (CTU)
  • Martin Girard (WUT)
  • Adam Kisiel (WUT)
  • Leszek Kosarzewski (WUT)
  • Grazyna Odyniec (LBNL)
  • Piotr Ostrowski (WUT)
  • Tomasz Pawlak (WUT)
  • Jan Pluta (WUT)
  • Michal Sumbera (NPI)
  • Barbara Trzeciak (WUT)
  • Hanna Zbroszczyk (WUT) - Chairperson
Conference duration: 3 days

STAR Regional Meeting: Heavy Quark Production and Correlations 2012 takes place at Faculty of Physics of Warsaw University of Technology

Upsilon pp, dAu, AuAu Paper Documents

 This page is for collecting the following documents related to the Upsilon pp (2009), dAu (2008) and AuAu (2010) paper:

Upsilon cross-section in p+p collisions at sqrt(sNN) = 200 GeV, 2009 data - h+/h-

h+/h-: Comparison Between the Reproduction vs the Original Production

L0 Trigger: Systematic Uncertainty