Jet quenching versus jet enhancement: a quantitative study of the BDMPS-Z gluon radiation spectrum

Abstract When an energetic parton propagates in a hot and dense QCD medium it loses energy by elastic scatterings or by medium-induced gluon radiation. The gluon radiation spectrum is suppressed at high frequency due to the LPM effect and encompasses two regimes that are known analytically: at high frequencies $$ \omega >{\omega}_c=\hat{q}{L}^2 $$ ω > ω c = q ̂ L 2 , where $$ \hat{q} $$ q ̂ is the jet quenching transport coefficient and L the length of the medium, the spectrum is dominated by a single hard scattering, whereas the regime ω < ωc is dominated by multiple low momentum transfers. In this paper, we extend a recent approach (dubbed the Improved Opacity Expansion (IOE)), which allows an analytic (and systematic) treatment beyond the multiple soft scattering approximation, matching this result with the single hard emission spectrum. We calculate in particular the NNLO correction analytically and numerically and show that it is strongly suppressed compared to the NLO indicating a fast convergence of the IOE scheme and thus, we conclude that it is sufficient to truncate the series at NLO. We also propose a prescription to compare the GW and the HTL potentials and relate their parameters for future phenomenological works.

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Soft Gluon Radiation off Heavy Quarks beyond Eikonal Approximation

Advances in High Energy Physics ◽

10.1155/2016/1298986 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10

Author(s):

Trambak Bhattacharyya ◽

Surasree Mazumder ◽

Raktim Abir

Keyword(s):

Quark Gluon Plasma ◽

Radiation Spectrum ◽

Eikonal Approximation ◽

Gluon Plasma ◽

Heavy Quarks ◽

Soft Gluon ◽

Plasma Medium ◽

Gluon Radiation ◽

Radiation Distribution ◽

Angle Scattering

We calculate the soft gluon radiation spectrum off heavy quarks (HQs) interacting with light quarks (LQs) beyond small angle scattering (eikonality) approximation and thus generalize the dead-cone formula of heavy quarks extensively used in the literatures of Quark-Gluon Plasma (QGP) phenomenology to the large scattering angle regime which may be important in the energy loss of energetic heavy quarks in the deconfined Quark-Gluon Plasma medium. In the proper limits, we reproduce all the relevant existing formulae for the gluon radiation distribution off energetic quarks, heavy or light, used in the QGP phenomenology.

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HEAVY QUARK ENERGY LOSS THROUGH SOFT QCD SCATTERING IN THE QGP

International Journal of Modern Physics E ◽

10.1142/s0218301307007489 ◽

2007 ◽

Vol 16 (07n08) ◽

pp. 2072-2078 ◽

Cited By ~ 1

Author(s):

KORINNA ZAPP ◽

GUNNAR INGELMAN ◽

JOHAN RATHSMAN ◽

JOHANNA STACHEL

Keyword(s):

Energy Loss ◽

Heavy Quark ◽

Jet Quenching ◽

Gluon Radiation ◽

Strong Suppression ◽

Charm Quarks ◽

Collisional Energy Loss ◽

Collisional Energy ◽

Model Based ◽

Quark Energy Loss

A strong suppression of non-photonic electrons in Au + Au collisions is observed at Rhic. This is in disagreement with the expected dominance of the energy loss via gluon radiation, which predicts a much weaker suppression of heavy flavours due to the dead cone effect. However, collisional energy loss is also important, as demonstrated recently by the Soft Colour Interaction Jet Quenching model. Based on this model we show that collisional energy loss of charm quarks gives a suppression of electrons of the observed magnitude, but the contribution from beauty decays, which dominates at intermediate and large p⊥, results in a somewhat weaker overall suppression of electrons than observed.

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Testing the Reliability of the Soft-Gluon Approximation for High p⊥ Particles

Proceedings ◽

10.3390/proceedings2019010013 ◽

2019 ◽

Vol 10 (1) ◽

pp. 13

Author(s):

Bojana Blagojevic ◽

Magdalena Djordjevic ◽

Marko Djordjevic

Keyword(s):

Energy Loss ◽

Jet Quenching ◽

Soft Gluon ◽

Radiative Energy ◽

Gluon Radiation ◽

Radiative Energy Loss ◽

First Order ◽

Analytical Expressions ◽

Made In

The soft-gluon approximation assumes that a high p ⊥ parton propagating through dense QCD matter loses only a small amount of its energy via gluon radiation. This assumption is made in many different jet quenching approaches, which nevertheless predicted a sizable radiative energy loss of such particles. This questions the reliability of this approximation, which must then be reconsidered. To address this issue, we relaxed the soft-gluon approximation within the DGLV formalism to the first order in opacity. The obtained analytical expressions are notably different from the soft-gluon case. Surprisingly the numerical effects that stem from waiving this assumption on fractional radiative energy loss and number of radiated gluons are small. Additionally, the effect on suppression is negligible, which can be intuitively understood by the cancellation of the opposite effects on the above mentioned variables. Consequently, our results surprisingly indicate that, contrary to the doubts mentioned above, the soft-gluon approximation remains well-founded within the DGLV formalism. We also investigate the effects of this assumption in the case of a dynamical medium, which suggests generality of the conclusions presented here.

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MEDIUM-INDUCED GLUON RADIATION AND JET QUENCHING IN HEAVY-ION COLLISIONS

Modern Physics Letters A ◽

10.1142/s0217732304013106 ◽

2004 ◽

Vol 19 (04) ◽

pp. 271-285 ◽

Cited By ~ 10

Author(s):

CARLOS A. SALGADO

Keyword(s):

Heavy Ion Collisions ◽

Heavy Ion ◽

High Energy ◽

Jet Quenching ◽

Gluon Radiation ◽

Initial State ◽

New Developments ◽

Ion Collisions ◽

Reliable Interpretation ◽

Comparison With Experimental Data

In this brief review, we summarize the new developments on the description of gluon radiation by energetic quarks traversing a medium as well as the observable consequences in high-energy heavy-ion collisions. Information about the initial state is essential for a reliable interpretation of the experimental results and will also be reviewed. Comparison with experimental data from RHIC and expectation for the future LHC will be given.

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JET MEASUREMENTS IN p+p AND D+Au COLLISIONS WITH STAR AT RHIC

International Journal of Modern Physics E ◽

10.1142/s0218301311020034 ◽

2011 ◽

Vol 20 (07) ◽

pp. 1651-1655

Author(s):

◽

JAN KAPITÁN

Keyword(s):

Quantitative Study ◽

Heavy Ion Collisions ◽

Heavy Ion ◽

Jet Quenching ◽

Dense Medium ◽

Initial State ◽

Ion Collisions ◽

Promising Tool ◽

200 Gev ◽

Nuclear Effects

Full jet reconstruction in heavy-ion collisions is a promising tool for the quantitative study of properties of the dense medium produced at RHIC. In addition to baseline measurements in p + p , results from d + Au collisions are needed to disentangle initial state nuclear effects from medium-induced k T broadening and jet quenching. We present mid-rapidity inclusive jet p T spectra and di-jet correlations (k T ) in 200 GeV p + p and d + Au collisions from the 2007-2008 RHIC run.

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Electron-Mirror Microscopic Aspects of Ferroelectric Domains of BaTiO3 And Ca2Sr (C2H5CO2)6

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069387 ◽

1970 ◽

Vol 28 ◽

pp. 478-479

Author(s):

Teruo Someya ◽

Jinzo Kobayashi

Keyword(s):

Surface Layer ◽

Electric Fields ◽

Quantitative Study ◽

Recent Progress ◽

Ferroelectric Domain ◽

Resolving Power ◽

Surface Pattern ◽

Crystal Surfaces ◽

One Dimensional ◽

Ferroelectric Domains

Recent progress in the electron-mirror microscopy (EMM), e.g., an improvement of its resolving power together with an increase of the magnification makes it useful for investigating the ferroelectric domain physics. English has recently observed the domain texture in the surface layer of BaTiO3. The present authors ) have developed a theory by which one can evaluate small one-dimensional electric fields and/or topographic step heights in the crystal surfaces from their EMM pictures. This theory was applied to a quantitative study of the surface pattern of BaTiO3).

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