At the early stage of heavy ion collisions, non-trivial topologies of the gauge fields can be created resulting in an imbalance of axial charge density and eventually separation of electric charges ...along the direction of the magnetic field produced in such collisions. This process is called the chiral magnetic effect (CME). In this work we implement such a charge separation at the partonic level in AMPT for Au+Au collisions at sNN=200GeV to study its consequence on experimental observables. We present the effects on the pion elliptic flow (v2) and the charged particle balance function (BF) for varying strengths of initial charge separation. We find that the shape of the balance function is sensitive to the increasing charge separation. v2 of pion shows a strong decreasing trend at higher transverse momenta (pT) with increasing charge separation. Charge balance functions show a peak at Δϕ∼180 with charge separation implemented in the partonic level as expected for the parity violation. We have also calculated parity observable γ in the form of BF's moments. γ shows a decreasing trend with charge separation. It has a negative value for charge separation produced by flipping more than 30% of quarks in the parton level. We also notice that <γ> for the same charge correlation and the opposite charge correlation shows negative and positive values, respectively.
The longitudinal asymmetry arises in relativistic heavy ion collisions due to fluctuation in the number of participating nucleons. This asymmetry causes a shift in the center of mass rapidity of the ...participant zone. The rapidity shift as well as the longitudinal asymmetry have been found to be significant at the top LHC energy for collisions of identical nuclei. We study the longitudinal asymmetry and its effect on charged particle rapidity distribution and anisotropic flow parameters at relatively lower RHIC energies using a model calculation. The rapidity shift is found to be more pronounced for peripheral collisions, smaller systems and also for lower beam energies due to longitudinal asymmetry. A detailed study has been done by associating the average rapidity shift to a polynomial relation where the coefficients of this polynomial characterize the effect of the asymmetry. We show that the rapidity shift may affect observables significantly at RHIC energies.
This paper, is devoted to the most important banking legislations for the day-to-day functioning of the State Bank of India, with respect to personnel policies. Special attention is given on the ...rules for the employees of State Bank of India and sortie important rules concerning functioning of the Bank. Department - The responsibility for the effective working and proper control over the cash department vests in the Cash Officer; under overall administrative control of the Branch Manager / Accountant. The work entrusted to the subordinate staff should be carried out in immediate presence of the Cash Officer, Deputy Cash Officer, Assistant Head Cashier or the Cashiers as the case may be. They are not at any time allowed to handle cash or other valuables independently.
The longitudinal asymmetry arises in relativistic heavy ion collisions due to fluctuation in the number of participating nucleons. This asymmetry causes a shift in the center of mass rapidity of the ...participant zone. The rapidity shift as well as the longitudinal asymmetry have been found to be significant at the top LHC energy for collisions of identical nuclei. We study the longitudinal asymmetry and its effect on charged particle rapidity distribution and anisotropic flow parameters at relatively lower RHIC energies using a model calculation. The rapidity shift is found to be more pronounced for peripheral collisions, smaller systems and also for lower beam energies due to longitudinal asymmetry. A detailed study has been done by associating the average rapidity shift to a polynomial relation where the coefficients of this polynomial characterize the effect of the asymmetry. We show that the rapidity shift may affect observables significantly at RHIC energies.
First experimental results are presented on event-by-event net-proton fluctuation measurements in Pb–Pb collisions at sNN=2.76 TeV, recorded by the ALICE detector at the CERN LHC. The ALICE detector ...is well suited for such studies due to its excellent particle identification capabilities and large acceptance, which is crucial for fluctuation analysis. The studies are focussed on second order cumulants, but the analysis technique used is more general and will be applied, in the near future, also to higher order cumulants.
At the early stage of heavy ion collisions, non-trivial topologies of the gauge fields can be created resulting in an imbalance of axial charge density and eventually separation of electric charges ...along the direction of the magnetic field produced in such collisions. This process is called the chiral magnetic effect (CME). In this work we implement such a charge separation at the partonic level in AMPT for Au+Au collisions at \(\sqrt{s_{NN}}\) = 200 GeV to study its consequence on experimental observables. We present the effects on the pion elliptic flow (\(v_2\)) and the charged particle balance function (BF) for varying strengths of initial charge separation. We find that the shape of the balance function is sensitive to the increasing charge separation. \(v_2\) of pion shows a strong decreasing trend at higher transverse momenta (\(p_T\)) with increasing charge separation. Charge balance functions show a peak at \(\Delta\phi \sim 180 \) with charge separation implemented in the partonic level as expected for the parity violation. We have also calculated parity observable \(\gamma\) in the form of BF's moments. \(\gamma\) shows a decreasing trend with charge separation. It has a negative value for charge separation produced by flipping more than 30 \(\%\) of quarks in the parton level. We also notice that \(<\gamma>\) for the same charge correlation and the opposite charge correlation shows negative and positive values, respectively.
The polarization of the Λ and Λ ¯ hyperons along the beam ( z ) direction, Pz , has been measured in Pb-Pb collisions at sNN=5.02 TeV recorded with ALICE at the Large Hadron Collider (LHC). The main ...contribution to Pz comes from elliptic flow-induced vorticity and can be characterized by the second Fourier sine coefficient Pz,s2= ⟨ Pzsin ( 2φ-2 Ψ 2 ) ⟩ , where φ is the hyperon azimuthal emission angle and Ψ 2 is the elliptic flow plane angle. We report the measurement of Pz,s2 for different collision centralities and in the 30%–50% centrality interval as a function of the hyperon transverse momentum and rapidity. The Pz,s2 is positive similarly as measured by the STAR Collaboration in Au-Au collisions at sNN=200 GeV , with somewhat smaller amplitude in the semicentral collisions. This is the first experimental evidence of a nonzero hyperon Pz in Pb-Pb collisions at the LHC. The comparison of the measured Pz,s2 with the hydrodynamic model calculations shows sensitivity to the competing contributions from thermal and the recently found shear-induced vorticity, as well as to whether the polarization is acquired at the quark-gluon plasma or the hadronic phase.
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