• DOI:10.1103/PhysRevC.84.044914
• Corpus ID: 118488966

Constituent quark scaling violation due to baryon number transport

@article{Dunlop2011ConstituentQS,
  title={Constituent quark scaling violation due to baryon number transport},
  author={John Charles Dunlop and Michael Annan Lisa and Paul Richard Sorensen},
  journal={Physical Review C},
  year={2011},
  volume={84},
  pages={044914}
}

• J. Dunlop, M. Lisa, P. Sorensen
• Published 15 July 2011
• Physics
• Physical Review C

In ultrarelativistic heavy-ion collisions at {radical}s{sub NN} {approx} 200 GeV, the azimuthal emission anisotropy of hadrons with low and intermediate transverse momentum (p{sub T} {approx}< 4 GeV/c) displays an intriguing scaling. In particular, the baryon (meson) emission patterns are consistent with a scenario in which a bulk medium of flowing quarks coalesces into three-quark (two-quark) 'bags.' While a full understanding of this number-of-constituent-quark (NCQ) scaling remains elusive, it is suggestive of a thermalized bulk system characterized by colored dynamical degrees of freedom - a quark-gluon plasma (QGP). In this scenario, one expects the scaling to break down as the central energy density is reduced below the QGP formation threshold; for this reason, NCQ-scaling violation searches are of interest in the energy scan program at the Relativistic Heavy Ion Collider. However, as {radical}s{sub NN} is reduced, it is not only the initial energy density that changes; there is also an increase in the net baryon number at midrapidity, as stopping transports entrance-channel partons to midrapidity. This phenomenon can result in violations of simple NCQ scaling. Still in the context of the quark coalescence model, we describe a specific pattern for the breakdown of the scaling that includes different flow strengths formore » particles and their antipartners. Related complications in the search for recently suggested exotic phenomena are also discussed.« less