Nuclear Experiment
We present measurements of the transverse-momentum dependence of elliptic flow $v_2$ for identified pions and (anti)protons at midrapidity ($|\eta|<0.35$), in 0%--5% central $p$$+$Au and $^3$He$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV.…
The large statistics accumulated during the LHC Run-1 and Run-2 have provided the unique opportunity to study the properties of the Quark-Gluon Plasma using rare hard probes. The ALICE Collaboration has presented new results on the jet…
The heavy flavor studies at RHIC help improve the knowledge of the bottom/charm quark production and can test Quantum Chromodynamics (QCD). Compared to the LHC/Tevatron, the RHIC heavy flavor production originates from different partonic…
The double-polarization observable $E$ was studied for the reaction $\gamma p\to p\omega$ using the CEBAF Large Acceptance Spectrometer (CLAS) in Hall B at the Thomas Jefferson National Accelerator Facility and the longitudinally-polarized…
Ultra-peripheral Pb-Pb collisions, in which the two nuclei pass close to each other, but at an impact parameter greater than the sum of their radii, provide information about the initial state of nuclei. In particular, heavy vector meson…
Highly energetic jets and photons are complementary probes for the kinematics and the topology of nuclear collisions. Jets are collimated sprays of charged and neutral particles, which are produced in the fragmentation of hard scattered…
We present results from STAR's first dedicated fixed-target run conducted in 2015 with Au + Au collisions at sqrt(s_NN) = 4.5 GeV. Directed flow of protons and lambdas, elliptic flow of identified hadrons, HBT radii, as well as pion, K^0_s,…
We present the first results from the STAR MTD of mid-rapidity charmonium measurements via the di-muon decay channel in p$+$p, p$+$Au, and Au$+$Au collisions at $\sqrt{s_{_{\rm NN}}}=200$~GeV at RHIC. The inclusive $J/\psi$ production cross…
In late 2015, the ALICE collaboration recorded data from Pb--Pb collisions at the unprecedented energy of \sqrt{s_{\rm NN}}~5.02~TeV. The transverse-momentum ($p_{\rm T}$) spectra of pions, kaons and protons are presented. The evolution of…
We present two measurements related to jet production in p+p and central Au+Au collisions at $\sqrt{{s}_{NN}}$=200 GeV. Firstly, a study of semi-inclusive charged recoil jets coincident with high-$\rm{p_{T}}$ direct-photon and neutral…
Heavy quarks (charm and bottom) are a sensitive probe of the Quark-Gluon Plasma (QGP) created in high-energy nuclear collisions. The modification of their phase-space in the QGP reflects the physical property of the QGP because they are…
Direct photons, being colorless objects, provide an unmodified control particle that can be used in conjunction with jets to probe the quark-gluon plasma. To leading order the direct photon momentum balances the momentum of opposing jets…
We report the first measurement of $\Lambda_c^+$ (average of $\Lambda_c^+$ and $\bar{\Lambda}_c^-$) baryon production and significantly improved measurement of $D_s^+$ (average of $D_s^+$ and $D_s^-$) meson production, within the rapidity…
At RHIC, enhancements in the baryon-to-meson ratio for light hadrons and hadrons containing strange quarks have been observed in central heavy-ion collisions compared to those in p+p and peripheral heavy-ion collisions in the intermediate…
We present STAR measurements of the charge-dependent three-particle correlator $\gamma^{a,b}=\langle \cos(\phi_1^{a}+\phi_2^{b}-2\phi_3)\rangle/v_{2}\{2\}$ and elliptic flow $v_{2}\{2\}$ in U+U, Au+Au and p+Au collisions at RHIC. The…
One key difference in current energy loss models lies in the treatment of the Altarelli-Parisi, AP, splitting functions. It has been shown that the shared momentum fraction, henceforth called Jet Splitting Function $z_g$ as determined by…
One key difference in current energy loss models lies in the treatment of the Altarelli-Parisi, AP, splitting functions. It has been shown that the shared momentum fraction, henceforth called Jet Splitting Function $z_g$ as determined by…
Direct photon-hadron correlations are a golden channel to study parton in-medium energy loss in QGP. The modification of the effective fragmentation function for the away-side jet can be measured by comparing integrated away-side yields of…
The ALICE experiment is dedicated to the study of the Quark-Gluon Plasma (QGP), a state of matter where, due to high temperature and density, quarks and gluons are deconfined. One of the probes studied to investigate this state of matter is…
The measurement of direct photon production in Pb-Pb collisions at $ \sqrt{s_{\rm{NN}}} = 2.76 $ TeV and in pp collisions at $ \sqrt{s}= 7 $ TeV with the ALICE experiment is presented. In Pb-Pb collisions a clear direct photon signal below…