Constituent quark scaling violation due to baryon number transport
Abstract
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 »
- Authors:
- Publication Date:
- Research Org.:
- Brookhaven National Lab. (BNL), Upton, NY (United States). Relativistic Heavy Ion Collider (RHIC)
- Sponsoring Org.:
- USDOE SC OFFICE OF NUCLEAR PHYSICS
- OSTI Identifier:
- 1049222
- Report Number(s):
- BNL-96763-2012-JA
Journal ID: ISSN 0556-2813; PRVCAN; R&D Project: PO-003; KB0202012; TRN: US1204415
- DOE Contract Number:
- DE-AC02-98CH10886
- Resource Type:
- Journal Article
- Journal Name:
- Physical Review, C (Nuclear Physics)
- Additional Journal Information:
- Journal Volume: 84; Journal Issue: 4; Journal ID: ISSN 0556-2813
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; ANISOTROPY; BARYON NUMBER; BARYONS; BREAKDOWN; COALESCENCE; DEGREES OF FREEDOM; ENERGY DENSITY; HADRONS; HEAVY IONS; QUARK MATTER; QUARKS; TRANSPORT; TRANSVERSE MOMENTUM; relativistic heavy ion collider
Citation Formats
C, Dunlop J, and Lisa, M.A., Sorensen, P. Constituent quark scaling violation due to baryon number transport. United States: N. p., 2011.
Web. doi:10.1103/PhysRevC.84.044914.
C, Dunlop J, & Lisa, M.A., Sorensen, P. Constituent quark scaling violation due to baryon number transport. United States. https://doi.org/10.1103/PhysRevC.84.044914
C, Dunlop J, and Lisa, M.A., Sorensen, P. 2011.
"Constituent quark scaling violation due to baryon number transport". United States. https://doi.org/10.1103/PhysRevC.84.044914.
@article{osti_1049222,
title = {Constituent quark scaling violation due to baryon number transport},
author = {C, Dunlop J and Lisa, M.A., Sorensen, P.},
abstractNote = {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 for particles and their antipartners. Related complications in the search for recently suggested exotic phenomena are also discussed.},
doi = {10.1103/PhysRevC.84.044914},
url = {https://www.osti.gov/biblio/1049222},
journal = {Physical Review, C (Nuclear Physics)},
issn = {0556-2813},
number = 4,
volume = 84,
place = {United States},
year = {Mon Oct 31 00:00:00 EDT 2011},
month = {Mon Oct 31 00:00:00 EDT 2011}
}