5 pages, 5 figures. Prepared for 3rd International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions (Hard Probes 2008), A Toxa, Spain, June 8-14, 2008
We report results on quarkonium production from the STAR experiment at the Relativistic Heavy-Ion Collider (RHIC). J/psi spectra in p+p and Cu+Cu collisions at sqrt(s) = 200 GeV with transverse momenta in the range of 0.5-14 GeV/c and 5-8 GeV/c, respectively, are presented. We find that for p_T > 5 GeV/c yields in p+p collisions are consistent with those in minimum-bias Cu+Cu collisions scaled with the respective number of binary nucleon-nucleon collisions. In this range the nuclear modification factor, R_AA, is measured to be 0.9+-0.2(stat). For the first time at RHIC, high-p_T J/psi-hadron correlations were studied in p+p collisions. Implications from our measurements on J/psi production mechanisms, constraints on open bottom yields, and J/psi dissociation mechanisms at high-p_T are discussed. In addition, we give a brief status of measurements of Upsilon production in p+p and Au+Au collisions and present projections of future quarkonia measurements based on an upgrades to the STAR detector and increased luminosity achieved through stochastic cooling of RHIC.
In this paper, we summarize the perspectives on quarkonia detection in the ALICE experiment at the CERN LHC, both in the dielectron and dimuon decay channels.
A Large Ion Collider Experiment - ALICE will become operational with the startup of the Large Hadron Collider - LHC at the end of 2007. One focus of the physics program is the measurement of quarkonia in proton-proton and lead-lead collisions. Quarkonia states will be measured in two kinematic regions and channels: di-muonic decays will be measured in the forward region by the muon arm, the central part of the detector will measure di-electronic decays. The presented studies show the expected performance of the di-electron measurement in proton-proton and central lead-lead collisions.
Quarkonia suppression in nucleus-nucleus collisions is a powerful tool to probe the density and temperature of the medium created in heavy ion collisions. Forward rapidity measurements in $p(d)$+Au collisions are essential to understand how quarkonia states are affected by initial state effects, formation time, and local particle multiplicity. Earlier measurements in Au+Au collisions showed a stronger suppression of forward $J/ψ$ compared to mid-rapidity results, indicating the possibility of a smaller contribution of regenerated quarkonia states at forward rapidity. These proceedings report o…
Quarkonia provide a sensitive probe of the properties of the hot dense medium created in high energy heavy ion collisions. Hard scattering processes result in the production of heavy quark pairs that interact with the collision medium during hadronization. These in-medium interactions convey information about the fundamental properties of the medium itself and can be used to examine the modification of the QCD confining potential in the collision environment. Baseline measurements from p+p and d+Au collision systems are used to distinguish cold nuclear matter effects while measurements from he…
Heavy Quarkonium states modifications in relativistic heavy ion collisions have been of great interest since the proposal by Matsui and Satz of J/psi suppression as a signature of Quark-Gluon Plasma (QGP) formation. Recent studies suggest that the excited states chi_c, psi(2S) and Upsilon(3S) melt sequentially[1,2] and the amount of observed suppression depends on the state and medium conditions. Therefore, this suppression pattern may be used as a probe of the medium temperature. In this work we present preliminary results on the charmonium and bottomnium measurements performed by the STAR ex…
Muons from the decay of charmonium resonances are detected in the ALICE Experiment at the Large Hadron Collider(LHC) for pp and Pb-Pb collisions with a muon spectrometer, covering the forward rapidity region 2.5$<$ $y$ $<$4.0. Analysis of the nuclear modification factor ($R_{\rm AA}$) at forward rapidity are presented and compared with mid-rapidity results from electrons in the central barrel covering $|y|<$0.9. The roles of suppression and regeneration mechanisms are discussed, as well as the importance of the results of the forthcoming p-Pb data taking for the estimate of cold nuclear matter…
The production of quarkonia in hadronic collisions provides a unique testing ground for understanding quantum chromodynamics (QCD) since it involves both the perturbative and non-perturbative regimes of this theory. Given that a satisfactory description of quarkonia production has not yet been achieved, new measurements that can provide new insights, helping to constrain models, are needed. The ALICE apparatus allows to measure inclusive J/$ψ$ production, as well as to separate prompt charmonia from those originating from b-hadron decays. The study of the azimuthal correlation of the emitted p…
ALICE is the dedicated heavy-ion experiment at the LHC. Its main physics goal is to study the properties of strongly-interacting matter at conditions of high energy density and high temperature expected to be reached in central Pb--Pb collisions. Charm and beauty quarks are well-suited tools to investigate this state of matter since they are produced in initial hard scatterings and are therefore generated early in the system evolution and probe its hottest, densest stage. ALICE recorded pp data at $\rm \sqrt{s}$ = 7 TeV and 2.76 TeV and Pb--Pb data at $\rm \sqrt{s}_{\rm NN}$=2.76 TeV in 2010 a…
Quarkonia (J/psi, psi', chi_C, Upsilon) production provides a sensitive probe of gluon distributions and their modification in nuclei; and is a leading probe of the hot-dense (deconfined) matter created in high-energy collisions of heavy ions. We will discuss the physics of quarkonia production in the context of recent p+p measurements at PHENIX. We next discuss Cold-Nuclear Matter (CNM) effects as seen in our measurements in $d+Au$ collisions - both for intrinsic physics such as gluon saturation and final-state dissociation, and as a baseline for studies in nucleus-nucleus collisions. Then we…
Measurements of quarkonia production in ultra-peripheral heavy-ion collisions are of important value to study photon-photon and photon-nucleus interactions, the partonic structure of nuclei, and mechanisms of vector-meson production. LHCb has studied both coherent $J/ψ$ and $ψ(2S)$ mesons in ultra-peripheral collisions using PbPb data at forward rapidity with the highest precision currently accessible. In addition, measurements of $Z$ production in $p$Pb collisions provide new constraints on the partonic structure of nucleons bound inside nuclei. Here will present these measurements of quarkon…
The PHENIX collaboration efforts towards constraining and understanding quarkonia production mechanisms are outlined. J/psi measurements and feed-down sources studies in p-p collisions at 200 GeV, together with their possible indications on the hadro-production mechanisms, are discussed. J/psi photo-production in ultra-peripheral collisions at 200 GeV is also examined. Finally, a glimpse of the first bottomonia results in minimum bias Au-Au collisions at 200 GeV and their implications are presented.
Heavy quarks (charm and bottom) are good probes of the hot and dense medium created in relativistic heavy ion collisions since they are mainly generated at the beginning of collisions and interact with the media in all collision stages. In addition, heavy flavor quarkonia production is thought to be uniquely sensitive to the deconfined medium of the Quark Gluon Plasma (QGP) through color screening. Heavy quark production has been studied by the PHENIX experiment at RHIC via measurements of single leptons from semi-leptonic decays in both the electron channel at mid-rapidity and in the muon cha…
Heavy-flavour hadrons, i.e. hadrons containing charm or beauty quarks, are effective probes to test perturbative-QCD (pQCD) calculations, to investigate the different hadronisation mechanisms, and to study the quark-gluon plasma (QGP) produced in relativistic heavy-ion collisions at the LHC. Measurements performed in pp and p-Pb collisions have recently revealed unexpected features not in line with the expectations based on previous measurements from $\rm{e^+e^-}$ and ep collisions, showing that charm fragmentation fractions are not universal. The investigation of initial-state effects such as…
We report new quarkonia measurements necessary to understand production mechanisms and cold nuclear matter effects in the yields observed at RHIC energy. Results obtained in p+p collisions collected during the 2006 RHIC Run include J/psi, Psi' and Upsilon differential cross sections as well as J/psi polarization. Revisited interpretations of the published J/psi nuclear modification factors and statistically improved observations in d+Au collisions taken in the 2008 Run are also discussed in the view of the recent understanding of the initial state effects and breakup cross section.
This writeup summarizes recent CMS results on quarkonia measurements in pp, pPb and PbPb collisions at LHC. The excellent muon detection capability of CMS allows measurement of charmonia states at high transverse momentum ($p_T$) while the $Υ$ states can be reconstructed starting at zero $p_T$. The absolute and relative yields of different charmonia and bottomonia states modified in PbPb collisions (over pp collisions) are described. The vertexing capability of CMS enables measurement of B meson energy loss via its decay to J/$ψ$. An overview of these measurements is given. How these measureme…
Quarkonia (J/Psi, Psi', Upsilon) production provides a sensitive probe of gluon distributions and their modification in nuclei; and is a leading probe of the hot-dense (deconfined) matter created in high-energy collisions of heavy ions. I will discuss our current understanding of the modification of gluon distributions in nuclei and other cold-nuclear-matter effects in the context of recent p-p and p(d)-A quarkonia measurements. Then I will review the latest results for nucleus-nucleus collisions from RHIC, and together with the baseline results from d-A and p-p collisions, discuss several alt…
In this proceedings the recent STAR results of $J/ψ$ and $Υ$ production in $p+p$, $d$+Au and Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV at mid-rapidity are reported. $J/ψ$ $p_{T}$ spectra in $p+p$ and Au+Au collisions for both low and high $p_{T}$ are shown. $J/ψ$ nuclear modification factor ($R_{AA}$) in $d$+Au and Au+Au collisions and $Υ$ $R_{AA}$ in Au+Au collisions are reported. Also, $J/ψ$ polarization in $p+p$ collisions and $J/ψ$ $v_{2}$ for semi-central Au+Au collisions are presented.
Quarkonia have been studied in different collision system and energy in order to understand the effects of the hot and dense medium created in heavy-ion collisions. CMS is well suited to measure quarkonia decays to muons given the muon identification and charged particle tracking capability. We report here prompt, non-prompt J/ψ, and Υ production measured by the CMS experiment in pp collisions at \sqrt{s}=7 TeV. In addition, the J/ψ and Υ production in PbPb at \sqrt{s_{NN}}=2.76 TeV and pp collisions at the same per nucleon energy are measured and compared. Prompt and non-prompt J/ψ contributi…
High energy heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) produce a novel medium characterized by an initial energy density over an order of magnitude above the expected phase transformation value and that then evolves as a nearly inviscid liquid. Probing the medium with auto-generated particles is a key methodology to quantitatively determine the medium properties. Pairs of heavy quarks are an excellent probe since their spatial separation to form various quarkonia states spans the relevant range of color screening lengths in the medium. In this proceedings, we describe r…
Measurements of coherent charmonium production cross sections together with their ratio in ultra-peripheral PbPb collisions are studied at a nucleon-nucleon centre-of-mass energy of $5.02\,\mathrm{TeV}$, the differential cross-sections are measured as a function of rapidity and transverse momentum, separately. The photo-production of \jpsi mesons at low transverse momentum is studied in peripheral PbPb collisions, which confirms coherent \jpsi production in hadronic collisions. These latest results significantly improve previous measurements and are compared with some theoretical predictions.
ALICE is the dedicated heavy-ion experiment at the Large Hadron Collider (LHC). It is designed to provide excellent capabilities to study the quark-gluon plasma (QGP) in the highest energy density regime opened up by the LHC. Quarkonia are crucial probes of the QGP. High-precision data from pp collisions are an essential baseline, and serve as a crucial test for competing models of quarkonium hadroproduction. ALICE measures quarkonia down to pt=0 via their decay channels into e+e- at central (|y|<0.9) and into mu+mu- at forward rapidity (-4.0<y<-2.5). We present first results on the transverse…
School of Physics and Astronomy, Sun Yat-Sen University(中山大学物理学院);Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing, Sun Yat-Sen University(中山大学广东省量子计量与传感重点实验室)
The production of different quarkonium states provides unique insight to the hot and cold nuclear matter effects in the strongly interacting medium that is formed in high energy heavy ion collisions. While LHC explores the energy frontier, RHIC has a broad physics program to explore the nuclear modification at different energies in a wide range of systems. Some of the most interesting recent results on $J/ψ$ and $Υ$ production in p+p, d+Au and A+A collisions from PHENIX and STAR are summarized in this work.
Studies of quarkonium production in heavy-ion collisions can be used for probing QGP properties. The suppression and regeneration of bound quarkonium states is sensitive to the medium properties. Modifications of the quarkonium polarization in Pb-Pb collisions with respect to pp collisions may give further insight into the suppression and regeneration mechanisms in the QGP. Quarkonia are also sensitive to the initial stages of heavy-ion collisions, and measurements in photonuclear collisions may help constrain the nuclear gluon-distribution at low Bjorken-$x$. In this work, recent quarkonium m…
The study of quarkonia in heavy-ion collisions has been the subject of intense experimental and theoretical effort, ever since their production was predicted to be sensitive to the formation of a deconfined state of strongly-interacting matter, known as the Quark-Gluon Plasma (QGP). In p-Pb collisions, Cold Nuclear Matter (CNM) effects, such as nuclear shadowing or partonic energy loss, are expected to influence quarkonium production. The study of such system is therefore crucial to shed light on the mechanisms taking place at the initial-state of quarkonium production, and to disentangle the …
Following on the discovery of a strongly interacting quark-gluon plasma (QGP) at RHIC, a program of detailed quarkonia measurements is crucial to understanding the nature of deconfinement. Lattice QCD calculations suggest a sequential melting of the quarkonia states in the deconfined medium. Such a melting would lead to a suppression in the measured charmonium and bottomonium yields. However, distinguishing a true suppression from shadowing, absorption, and recombination effects requires detailed measurements of the charmonium states (J/psi, psi', and chi_c) and bottomonium states (Y(1S), Y(2S…
Quarkonia were predicted to be suppressed in the "hot" deconfined matter known as the Quark Gluon Plasma (QGP), but they were also seen to suffer from "cold" nuclear matter effects (parton shadowing, nuclear absorption...). Both at SPS and RHIC, suppression beyond nuclear effects was observed, but the rapidity dependence of the RHIC result is not easy to interpret. I review here the current status of these results, their possible interpretations and the new measurements that could provide insights on quarkonia suppression. Some of them were presented at this conference.
The measurement of quarkonia production in relativistic heavy ion collisions provides a powerful tool for studying the properties of the hot and dense matter created in these collisions. To be really useful, however, such measurements must cover a wide range of quarkonia states and colliding species. The PHENIX experiment at RHIC has successfully measured J/psi, psi-prime, chi_c and Upsilon production in different colliding systems at various energies. In this talk I will present recent results from the PHENIX collaboration on charmonium production in d+Au, Cu+Au and U+U collisions at 200 GeV/…
In pp collisions at LHC energies, heavy quarks are produced in initial hard scatterings and then these quarks hadronize in either open heavy-flavor hadrons or quarkonia (e.g. J/$ψ$, $ψ(2S)$, $Υ$). The study of quarkonium production as a function of charged-particle multiplicity links soft and hard processes and allows one to study their interplay. While a linear increase of quarkonium production as a function of charged-particle multiplicity can be reasonably well understood in the context of multi-parton interactions, the observation of deviations with respect to a linear increase requires a …
Massachusetts Institute of Technology(麻省理工学院);Lawrence Berkeley National Laboratory(劳伦斯伯克利国家实验室);Brookhaven National Laboratory(布鲁克海文国家实验室);Los Alamos National Laboratory(洛斯阿拉莫斯国家实验室)
The cross-sections of coherent \jpsi and \psitwos production in ultra-peripheral PbPb collisions at a nucleon-nucleon center-of-mass energy of $5.02\,\mathrm{TeV}$ are measured using a data sample collected in 2018 at $\lhcb$, and the differential cross-sections are measured separately as a function of transverse momentum and rapidity. The photo-production of \jpsi mesons at low transverse momentum is studied in peripheral PbPb collisions, \jpsi candidates are reconstructed through the prompt decay into \mumu in the rapidity region of $2.0<y<4.5$. These results significantly improve previous m…
Suppression of quarkonia in heavy ion collisions with respect to proton-proton collisions due to the Debye screening of the potential between the heavy quarks was hypothesized to be a signature of the Quark Gluon Plasma (QGP). However, other effects besides Debye screening, such as the statistical recombination of quark anti-quark heavy flavor pairs, or co-mover absorption can also affect quarkonia production in heavy ion collisions. Quantifying the suppression of an entire family of quarkonium mesons can give us a model dependent constraint on the temperature. The suppression of Upsilon can b…
We study different processes responsible for the modification of quarkonia yields in the medium produced in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. The quarkonia and heavy flavour cross sections are estimated using the measurements in pp collisions at LHC energies and shadowing corrections are obtained using the EPS09 parametrizations. A kinetic model is used which incorporates quarkonia suppression inside the Quark Gluon Plasma (QGP), suppression due to hadronic comovers, and regeneration from recombination of heavy quark pairs. The quarkonia dissociation cross section due to gluon col…
In these proceedings, we report on the production of various open heavy-flavor hadrons and quarkonia in Au+Au collisions at sNN = 200GeV from the STAR experiment.
We study exclusive charmonium and bottomonium production in ultra-peripheral heavy-ion collisions and electron-ion collisions within the dipole picture. We employ heavy quarkonium light-front wavefunctions obtained within the basis light-front quantization framework, which has some features of the light-front holographic QCD. We focus on comparison with measurements of exclusive charmonium and bottomonium production in ultraperipheral $pp$, $p$Pb and PbPb collisions at LHC and find reasonable agreement with the cross sections. We also discuss the coherent production cross-section ratios of exc…
Open heavy-flavour and quarkonia measurements are important tools to study the hot and dense partonic medium formed in ultra-relativistic heavy-ion collisions. The modification of their production in those collisions, with respect to the pp and p-Pb ones, can help in the characterization of this medium. Quarkonia and open heavy-flavour production is measured in ALICE in the three different collision systems, at mid- and forward rapidity. A selection of those results recently obtained in Pb-Pb and p-Pb collisions by the ALICE Collaboration is presented.
Quarkonia ($J/ψ$, $ψ$', $Υ$) production provides a sensitive probe of gluon distributions and their modification in nuclei; and is a leading probe of the hot-dense (deconfined) matter created in high-energy collisions of heavy ions. We will discuss the current understanding of the production process and of the cold-nuclear-matter effects that modify this production in nuclei in the context of recent p+p and p(d)+A quarkonia measurements. Then we will review the latest results for nucleus-nucleus collisions from RHIC, and together with the baseline results from d+A and p+p collisions, discuss s…
This paper presents the CMS measurements of quarkonia and open heavy flavor production in \pp, \pPb, and \PbPb collisions at \sqrtsnn = 2.76 and 5.02 TeV. A brief outlook of the near-future CMS heavy flavor physics analyses is provided at the end.
Measurements of quarkonia (heavy quark and antiquark bound states) and open-heavy flavour hadrons in hadronic collisions provide a unique testing ground for understanding quantum chromodynamics (QCD). Although recently there was significant progress, our understanding of hadronic collisions has been challenged by the observation of intriguing effects in high-multiplicity proton-proton (pp) and p-Pb collisions, such as collective phenomena. The excellent particle identification, track and decay-vertex reconstruction capabilities of the ALICE experiment are exploited to measure quarkonia as well…
Heavy quarks are produced at the first instant of a nucleus--nucleus collision and therefore are an important tool to study the subsequent high energy-density medium formed in ultra-relativistic heavy-ion collisions. A series of experimental efforts for understanding the properties of the Quark--Gluon Plasma (QGP), a medium consisting of a deconfined state of quarks and gluons, are based on measuring the bound states of heavy quark--anti-quark pairs known as quarkonia. However, the medium modification of heavy-flavour hadron production includes also the contribution of Cold Nuclear Matter (CNM…
Quarks of heavy flavors are useful tool to study quark-gluon plasma created in heavy-ion collisions. Due to their high mass and early production time, heavy quarks experience the entire evolution of the system created in these collisions. Open heavy flavor meson measurements are sensitive to the energy loss in the QGP, while quarkonia are sensitive to the temperature of the QGP as they dissociate because of Debye-like screening of color charges. This presentation is a summary of the latest heavy flavor studies performed at RHIC. Results from both STAR and PHENIX experiments are presented, comp…
Three measurements that broaden the scope of the experimental investigation of quarkonia modifications in heavy ion collisions are presented. Although the current statistical precision on the first two measurements does not allow one to draw significant conclusions, J/$ψ$ elliptic flow and high pT suppression results are important proofs of principle measurements, and make the case for higher luminosities at RHIC. Finally, the first measurement of an upper limit on the nuclear modification R_AA of dielectrons in the $Υ$ mass region in Au+Au collisions is presented. The results show a significa…
Heavy quarks are produced in the early stages of nucleus-nucleus collisions and can therefore provide important insight into the Quark-Gluon Plasma (QGP). Quarkonia are proposed as crucial probes to study the QGP. The extent of the medium modification for heavy-quark quarkonium production in heavy-ion collisions is measured in terms of a nuclear modification factor $R_{\rm AA}$, defined as the quarkonium yield in heavy-ion collisions divided by the relative quarkonium cross section in pp collisions scaled by the nuclear overlap function. A possible path-length dependent quarkonium dissociation…
Using the dilute-dense factorization in the Color Glass Condensate framework, we investigate the azimuthal angular correlation between a heavy quarkonium and a charged light hadron in proton-nucleus collisions. We extract the second harmonic $v_2$, commonly known as the elliptic flow, with the light hadron as the reference. This particular azimuthal angular correlation between a heavy meson and a light hadron has first been measured at the LHC recently. The experimental results indicate that the elliptic flows for heavy-flavor mesons ($J/ψ$ and $D^0$) are almost as large as those for light had…
The main focus of the heavy flavor program at RHIC is to investigate the properties of the dense matter produced in heavy-ion collisions by studying its effect on open heavy flavor and quarkonia production. This in turn requires a detailed understanding of their production in elementary p+p collisions so that the dense matter effects can be later unfolded. In this paper, we present the first mid-rapidity cross section measurement of bottomonium at $\sqrt{s}=200$ GeV with the STAR experiment. We compare our results with perturbative QCD calculations. A brief status on the study of charmonium in…
In recent years, PHENIX has studied many important observables related to heavy-flavor physics through their leptonic decay measurements including the invariant yield of electrons from nonphotonic sources, and prompt single muons, both of which are dominated by D and B mesons. Charm and beauty cross-sections were measured and compared through single lepton, and lepton-hadron correlations in p+p collisions at $\sqrt{s}$ = 200 GeV. Observables for quarkonia production such as invariant yield and polarization were also measured in p+p collisions. In Au+Au collisions, preliminary results for the $…
The dissociation of quarkonia in the medium created in heavy ion collisions is still one of the most debated topics in the heavy ion community. Progress in understanding the effect relies on a broad range of measurements in collisions with different nuclear sizes, covering a broad rapidity range. This presentation will report the $J/ψ$ measurements performed by the PHENIX collaboration at forward and backward rapidities of 1.2 $< |y| <$ 2.2 in $p$+Al, $p$+Au, and $^3$He+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV, and the corresponding nuclear modification factors.
The study of quarkonium production in relativistic heavy ion collisions provides insight into the properties of the produced medium. The lattice studies show a sequential suppression of quarkonia states when compared to normal nuclear matter; which further affirms that a full spectroscopy including bottomonium can provide us a better thermometer for the matter produced under extreme conditions in relativistic heavy ion collisions. With the completion of the STAR Electromagnetic Calorimeter and with the increased luminosity provided by RHIC in Run 6 and 7, the study of $Υ$ production via the di…
The inclusive production cross sections at forward rapidity of J/$ψ$, $ψ$(2S), $Υ$(1S) and $Υ$(2S) are measured in pp collisions at $\sqrt{s} = 7$ TeV with the ALICE detector at the LHC. The analysis is based in a data sample corresponding to an integrated luminosity of 1.35 pb$^{-1}$. Quarkonia are reconstructed in the dimuon-decay channel and the signal yields are evaluated by fitting the $μ^+μ^-$ invariant mass distributions. The differential production cross sections are measured as a function of the transverse momentum $p_{\rm T}$ and rapidity $y$, over the ranges $0 < p_{\rm T} < 20$ GeV…
Quarkonia represent excellent tools for understanding the role of multiparton interactions (MPI) in small systems, i.e., pp and p-A collisions. Probing MPI with quarkonia can be done directly by looking at quarkonium associated production, or indirectly by studying the multiplicity dependence of quarkonium production. In these proceedings, the results from the ALICE experiment on direct and indirect MPI probes are discussed. The self-normalized yields of charmonium production as a function of the charged-particle multiplicity in pp and p--Pb collisions at \sqrt{s} = 13 TeV and \sqrt{s_{NN} = 8…
Measurements of quarkonium production in heavy-ion collisions have played an essential role in understanding the properties of the Quark Gluon Plasma created in such collisions. In early 2014, the Muon Telescope Detector, designed to trigger on and identify muons based on its precise timing information, was fully installed in STAR. It opens the door to measure quarkonia via the di-muon channel for the first time at the STAR experiment, with the potential to separate different Υ states. In this talk, we present the measurements of J/ψ suppression and elliptic flow at mid-rapidity in Au+Au colli…
In these proceedings, an overview of recent quarkonium measurements in nuclear collisions carried out at both RHIC and LHC is presented. In p+p collisions, despite theoretical progresses made in understanding the production mechanisms for quarkonia, a complete picture is still yet to be achieved. In p+A collisions where measurements are done to quantify the cold nuclear matter effects, significant suppression of quarkonium production is observed for low transverse momentum region at both forward- and mid-rapidities. Furthermore, results from A+A collisions show the interplay of dissociation an…