[en] In the relativistic heavy ion collisions, the initial spatial anisotropy due to the asymmetric geometric overlap of two colliding nuclei evolves into the observed final state, consisting of large numbers of produced particles with anisotropic momentum distributions in the transverse plane. We report on measurement of the elliptic (υ₂), triangular (υ₃) and quadrangular (υ₄) flow coefficients of charged particles at midrapidity, |η| < 0.8, for the transverse momentum range 0.2 < p_T < 20 GeV/c in Pb+Pb collisions at √S_NN = 2.76 TeV measured with the ALICE detector at the LHC. To extract the flow coefficients the event plane method is used. A set of ALICE forward detectors cover the pseudorapidity range of 2.5 < |η| < 5.1, and are sensitive to the azimuthal asymmetry of charged particles and inclusive photons. A large η gap between the charged particles reconstructed at midrapidity for which the flow coefficients are estimated and forward detectors used to obtain the event plane ensures the suppression of non-flow correlations. Results are compared with existing measurements at RHIC and LHC and also with hydrodynamic model calculations

[en] We explain by quantal density functional theory the physics of mapping from any bound nondegenerate excited state of Schroedinger theory to an S system of noninteracting fermions with equivalent density and energy. The S system may be in a ground or excited state. In either case, the highest occupied eigenvalue is the negative of the ionization potential. We demonstrate this physics with examples. The theory further provides a new framework for calculations of atomic excited states including multiplet structure

[en] Self-consistent density-functional calculations, in an exchange-only framework, are reported for the energies and moments of the 2³S excited states of the helium isoelectronic sequence. The total energy values show excellent agreement with exact nonrelativistic values while the moments are also quite satisfactory. (author). 18 refs., 1 fig., 3 tabs

[en] Silicon carbide (SiC) radiation detectors are being developed for high-temperature applications in harsh radiation environments. The wide band gap of SiC (3.25 eV) compared to conventional semiconductors such as silicon (1.1 eV) and the relatively high-radiation resistance of SiC make it a semiconductor, that is highly suited for such applications. In this paper, we report on charged particle response measurements with larger-sized diodes. The charged-particle response characteristics of these diodes were tested with ²³⁸Pu, ²⁴²Pu and ¹⁴⁸Gd alpha-particle sources in air. Energies deposited by alpha particles from these sources were calculated using the SRIM range-energy code. The peak shapes are nearly Gaussian, with a full-width at half-maximum for ¹⁴⁸Gd of 89.5 keV corresponding to 1562 keV deposited in the detector active volume. This measured resolution is greater than, but still comparable to, the resolution obtained with silicon alpha spectrometers. Range straggling for the energy fraction deposited in the 10-μm thick active layers contributes significantly to our observed energy resolution. Design parameters for an optimum SiC alpha spectrometer are discussed

[en] Resonances are used to study the properties of the strongly interacting hot and dense matter produced in ultrarelativistic heavy-ion collisions. The system produced in such collisions evolves through different stages from early partonic phase to the hadronic one. Resonances can probe the existence of hadron rescattering and regeneration effects after hadronization. These effects can change resonance yields which are measured through their hadronic decay channels

[en] We present new measurements related to spin alignment of K^*0 vector mesons at mid-rapidity for Pb–Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76\text{and}5.02\text{TeV}$. The spin alignment measurements are carried out with respect to production plane and 2^nd order event plane. At low p_T the spin density matrix element ρ₀₀ for K^*0 is found to have values slightly below 1/3, while it is consistent with 1/3, i.e. no spin alignment, at high p_T. Similar values of ρ₀₀ are observed with respect to both production plane and event plane. Within statistical and systematic uncertainties, ρ₀₀ values are also found to be independent of $\sqrt{s_{\mathrm{NN}}}$. ρ₀₀ also shows centrality dependence with maximum deviation from 1/3 for mid-central collisions with respect to both the kinematic planes. The measurements for K^*0 in pp collisions at $\sqrt{s}=13\text{TeV}$ and for K⁰_S (a spin 0 hadron) in 20-40% central Pb–Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76\text{TeV}$ are consistent with no spin alignment.

[en] The system created in ultrarelativistic non central heavy-ion collisions exhibits a large orbital angular momentum. We have presented the measurements of spin alignment of K^*0 and polarization of Λ. The measured polarization values of Λ hyperons are consistent with zero within the precision of the measurement and follow the trend of polarization decreasing with increasing energy as observed by the STAR collaboration. The measured value of ρ₀₀ for K^*0 vector meson is less than 1/3 for p_T < 2 GeV/c hinting at a possible spin alignment in Pb-Pb collisions at √sNN = 2.76 TeV

[en] The elliptic flow (ν₂) measurements are believed to provide information on the dynamics of the system formed in the heavy-ion collisions. In the present work, the inclusive photons ν₂ which can be measured has been studied using heavy-ion collision models. If the collisions at lower and higher energies require different cross-sections for explaining the measured distributions, it would expect a breakdown of the longitudinal scaling

[en] We present a method for studying the detection of jets in high energy hadronic collisions using multiplicity detectors at forward rapidity. Such a study enhances the physics scope of multiplicity detectors at forward rapidities in LHC. At LHC energies the jets may be produced with significant cross section at forward rapidities. A multi-resolution wavelet analysis technique can locate the spatial position of jets due to its feature of space-scale locality. The discrete wavelet proves to be very effective in probing physics simultaneously at different locations in phase space and at different scales to identify jet-like events. The key feature this analysis exploits is the difference in particle density in localized regions of the detector due to jet-like and underlying events. We find that this method has a significant sensitivity towards detecting jet position and its size. The jets can be found with the efficiency and purity of the order of 46% with a cut of three times the root mean square of the typical wavelet coefficients distribution in minimum bias events.

[en] More than 200 low-lying and moderately high-lying doubly excited states (^1.3S^e, ³P^o, ^1.3D^e, ^1.3F^o, ¹G^e) of He-isoelectronic systems (Z = 2-5) have been studied in the nonrelativistic Hohenberg-Kohn-Sham density-functional framework by incorporating the nonvariational work-function exchange potential suggested by Harbola and Sahni and a simple parametrized local Wigner-type correlation functional. In essence, a Kohn-Sham-type equation has been solved numerically. Our results on excited-state energies, excitation energies and differences between excitation energies are in good agreement with available experimental and theoretical results. In 50% of cases, the percentage deviation in the calculated excitation energy is less than unity. The estimates of the relatively small distances (0.02-0.1 au) of the He states below the corresponding N = 2, 3 4 ionization thresholds are in error by 0.5-34.9%, indicating that the Wigner correlation functional needs to be improved for greater accuracy. The excited radial densities display expected structures. Some new states are reported. (author)