Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)最新文献

{"title":"Modeling coherence effects of gluon emission for heavy flavor studies","authors":"W. Ke, Yingru Xu, S. Bass","doi":"10.22323/1.355.0032","DOIUrl":"https://doi.org/10.22323/1.355.0032","url":null,"abstract":"Heavy quarks with large transverse momenta lose energy mainly through radiative processes. However, a Monte-Carlo implementation of gluon emission in an event-by-event fluctuating medium background is a non-trivial task. This is because the Landau-Pomeranchuk-Migdal (LPM) effect of the medium-induced bremsstrahlung introduces coherence over long distances that may be comparable to the typical expansion time scale or even the size of the QGP fireball. We have developed a new partonic transport model to implement the LPM effect approximately. The simulated in-medium bremsstrahlung spectra quantitatively agree with leading order theory calculations in a static medium and also display expected reduction in an expanding medium. Integrating the transport model into a multistage heavy-flavor dynamical model for heavy-ion collisions, we extract the heavy-quark transport coefficient by comparing to open heavy-flavor measurements at the LHC.","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115248186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From Saturation to high $p_t$ jets: toward a unified picture of particle production at all transverse momenta","authors":"J. Jalilian-Marian","doi":"10.22323/1.355.0011","DOIUrl":"https://doi.org/10.22323/1.355.0011","url":null,"abstract":"We propose a new formalism that aims to unify particle production in high energy hadron/nucleus collisions; from collinear factorization approach in pQCD at high pt (large x) to Color Glass Condensate framework which describes multi-particle production at low pt (small x). To do so we consider scattering of a quark projectile from a classical color field representing small x gluons of the target to all order in the field and a dynamical gluon field representing large x gluons of the target proton or nucleus. We then compute the \"tree-level\" scattering cross section. We discuss the effects of the one-loop corrections to our tree-level cross section which is expected to lead to leading twist pQCD and DGLAP evolution equation of the cross section at high pt and the JIMWLK evolution equation of Color Glass Condensate at low x.","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117091451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probing the Constituent of QCD Plasma in CUJET3.1/CIBJET framework","authors":"S. Shi, J. Liao, M. Gyulassy","doi":"10.22323/1.355.0030","DOIUrl":"https://doi.org/10.22323/1.355.0030","url":null,"abstract":"In this proceeding we report results of a comprehensive global analysis of ultra-relativistic heavyion collision data using the updated CUJET3.1 framework. By comparing CUJET results with (CUJET3.1) versus without (CUJET2.0) chromo-magnetic monopole (cmm) degrees of freedom, we find that the cmm scenario is more favored by experimental data. Finally, we use the event-byevent generalization of the CUJET framework, CIBJET, and show that fluctuations in the initial conditions do not significantly alter our conclusions for RAA and v2.","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127487823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurements and Calculations of $hat{q}L$ via transverse momentum broadening in RHI collisions using di-hadron correlations","authors":"M. Tannenbaum","doi":"10.22323/1.355.0021","DOIUrl":"https://doi.org/10.22323/1.355.0021","url":null,"abstract":"The renewed interest in analyzing RHIC data on di-hadron correlations as probes of final state transverse momentum broadening as shown at Quark Matter 2018~cite{MiklosQM2018} by theoretical calculations~cite{ChenCCNUPLB773} compared to experimental measurements~cite{PXppg074, STARPLB760} led me to review the quoted theoretical calculations and experimental measurements because the theoretical calculation~cite{ChenCCNUPLB773} does not show the correct errors of the PHENIX measurements~cite{PXppg074,PXppg083} as published. The above references were checked and fits were performed to the published measurements with the correct errors~cite{PXppg074,PXppg083} to determine $hat{q}L$ from the measured azimuthal broadening to compare with the theoretical calculation~cite{ChenCCNUPLB773}. The new fits with the correct errors give values of on the order of \u0000$-1pm 1$ GeV$^2$, clearly inconsistent with the value of $hat{q}L=13$ GeV$^2$ claimed in the theoretical calculations~cite{ChenCCNUPLB773}. One STAR measurement~cite{STARPLB760}, that I had previously analyzed~cite{MJTPLB771}, quoted in Ref.~cite{ChenCCNUPLB773} gave a value of $ =0.86pm 0.87$ GeV$^2$ also inconsistent with the theoretical claim~cite{ChenCCNUPLB773}. As a check I calculated the values of $hat{q}L$ from a more recent PHENIX measurement with superior errors~cite{ppg106}. The values of $hat{q}L$ from these measurements also had the interesting effect of being consistent with zero for larger values of associated $p_{Ta}geq 3$ GeV/c. This effect is well known from all previous measurements of the ratio of the $p_{Ta}$ distributions in Au+Au to p+p for a given trigger $p_{Tt}$ called $I_{AA}$~cite{STARPLB760,ppg106,ALICEPLB763} which remain constant for $p_{Ta}geq 3$ GeV/c. One possible explanation is that for $p_{Ta}geq 3$ GeV/c, which is at a fraction $approx 1$% of the $x_Eapprox p_{Ta}/p_{Tt}$ distribution, these hard fragments are distributed narrowly around the jet axis so that they are not strongly affected by the medium~cite{YacineIJMPA}. Hence, di-jets rather than di-hadrons at RHIC are proposed as an improved azimuthal broadening measurement to determine $hat{q}L$ and possibly $hat{q}$.","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133157406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Generator-level studies for Z/photon-tagged jet measurements and effects of angular resolution driven by heavy-ion background","authors":"K. Tatar","doi":"10.22323/1.355.0016","DOIUrl":"https://doi.org/10.22323/1.355.0016","url":null,"abstract":"Photon+jet events are generated using PYTHIA 8 and their fraction of quark-jet and gluon-jet events are studied by mapping the photon+jet production to parton densities. Measurements had shown that photon+jet momentum imbalance and azimuthal angle correlations have wide distributions even in the absence of a QCD medium. Sources of widening are investigated via parton level processes in PYTHIA 8, finding that initial-state radiation is the dominant source. Correlations at RHIC energies are shown to have sharper distributions than those at LHC energies, as the effects of vacuum processes become smaller with lower collision energy. Sensitivity of jet observables to the heavy-ion underlying event (UE) are studied using toy events. Jet observables are compared between jets recombined with E-scheme and winner-take-all (WTA) schemes. The jet pointing angle in WTA scheme is found to be much less sensitive to the heavy-ion UE.","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116886499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Systematic studies of di-jet imbalance measurements at STAR","authors":"N. Elsey","doi":"10.22323/1.355.0024","DOIUrl":"https://doi.org/10.22323/1.355.0024","url":null,"abstract":"","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"137 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127513602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PHENIX Results of $π^0$-Hadron Correlation","authors":"Cheuk-Ping Wong","doi":"10.22323/1.355.0004","DOIUrl":"https://doi.org/10.22323/1.355.0004","url":null,"abstract":"","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116167923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Event plane dependence of jet quenching studied via azimuthal correlations and differential jet shape in Au--Au collisions at $sqrt{s_{NN}}=200$ GeV with the STAR detector at RHIC","authors":"J. Mazer","doi":"10.22323/1.355.0014","DOIUrl":"https://doi.org/10.22323/1.355.0014","url":null,"abstract":"Jet quenching, which describes the energy lost by jets while interacting with the medium, can be studied using azimuthal correlations of associated hadrons with respect to a trigger jet, and by probing the jet substructure by measuring the differential jet shape. This work will present details of both analyses and explore the impact of a jet’s orientation with respect to the event plane, defined by the beam direction and the vector of the impact parameter. This will allow for the study of the path length dependence of medium modifications to the jets and their associated hadrons. Both analyses will reconstruct full (charged + neutral) jets in mid-peripheral Au+Au collisions at √ sNN = 200 GeV with the STAR detector at RHIC. The analysis for the event plane dependent jet-hadron correlations uses a robust method, known as the Reaction Plane Fit (RPF) method to remove the complex, flow-dominated heavy-ion background from the correlation functions. The event plane dependence of jet-correlated yields is quantified through ratios of yields from different jet azimuthal angle with respect to the event plane. Compared to a similar measurement made by the ALICE Collaboration, STAR has increased statistics and smaller uncertainties. No significant path length dependence of jet modifications in the medium is seen within uncertainties, which is consistent with the previous conclusion at the LHC. A first study of the differential jet shape at RHIC energies is performed with an extension to also include the event plane dependence. The jet shape variable will be used to probe the internal jet structure by looking at the radial profile of transverse momentum inside the most energetic jet of each triggered event (leading jet). This work shows early hints of a possible event plane dependence of the differential jet shape and motivates further study.","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"139 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127212703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gamma-hadron and related Two- Particle Azimuthal correlations studies in PHENIX","authors":"A. Pun","doi":"10.22323/1.355.0001","DOIUrl":"https://doi.org/10.22323/1.355.0001","url":null,"abstract":"","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123971200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detector Concepts of the Electron-Ion Collider","authors":"J. Repond","doi":"10.22323/1.355.0015","DOIUrl":"https://doi.org/10.22323/1.355.0015","url":null,"abstract":"","PeriodicalId":210258,"journal":{"name":"Proceedings of 13th International Workshop in High pT Physics in the RHIC and LHC Era — PoS(High-pT2019)","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126171452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}