Azimuthal correlations of D-mesons in pp+pp and pp+Pb collisions at LHC energies

We study the correlations of D mesons produced in $p$+$p$ and $p$+Pb collisions. These are found to be sensitive to the effects of the cold nuclear medium and the transverse momentum ($p_T$) regions we are looking into. In order to put this on a quantitative footing, as a first step we analyse the azimuthal correlations of D meson-charged hadron(Dh), and then predict the same for D meson -anti D meson ($D\overline{D}$) pairs in $p$+$p$ and $p$+Pb collisions with strong coupling at leading order $\cal{O}$($\alpha_{s}^{2}$) and next to leading order $\cal{O}$($\alpha_{s}^{3}$) which includes space-time evolution (in both systems), as well cold nuclear matter effects (in $p$+Pb). This also sets the stage and baseline for the identification and study of medium modification of azimuthal correlations in relativistic collision of heavy nuclei at the Large Hadron Collider.Comment: 12 pages, 4 figure

Evaluating the Utility of Fly Ash for Waste Containment Application

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Qualitative aspects of Volterra integro-dynamic system on time scales

This paper deals with the resolvent, asymptotic stability and boundedness of the solution of time-varying Volterra integro-dynamic system on time scales in which the coefficient matrix is not necessarily stable. We generalize at time scale some known properties about asymptotic behavior and boundedness from the continuous case. Some new results for discrete case are obtained

Empirical determination of charm quark energy loss and its consequences for azimuthal anisotropy

We propose an empirical model to determine the form of energy loss of charm quarks due to multiple scatterings in quark gluon plasma by demanding a good description of production of D mesons and non-photonic electrons in relativistic collision of heavy nuclei at RHIC and LHC energies. Best results are obtained when we approximate the momentum loss per collision $\Delta p_T \propto \alpha \, p_T$, where $\alpha$ is a constant depending on the centrality and the centre of mass energy. Comparing our results with those obtained earlier for drag coefficients estimated using Langevin equation for heavy quarks we find that up to half of the energy loss of charm quarks at top RHIC energy could be due to collisions while that at LHC energy at 2760 GeV/A the collisional energy loss could be about one third of the total. Estimates are obtained for azimuthal anisotropy in momentum spectra of heavy mesons, due to this energy loss. We further suggest that energy loss of charm quarks may lead to an enhanced production of D-mesons and single electrons at low $p_T$ in AA collisions.Comment: 11 pages, 3 figures, Typographical errors corrected, Key-words and PACS indices added, sequence of figures corrected, references added in section 3, discussions expande

Child protection in Pakistan: Legislation & implementation

Children are an integral part of any society. Their dependency on others for the fulfilment of their basic needs like food, shelter, education, safety and security makes them a vulnerable group. Society is judged on its ability to provide for the needs of the vulnerable. Provision of each of these needs is the responsibility of primary caregivers but requires assistance from multiple agencies working at the national level to ensure an effective delivery. Children’s rights can be defined as “the rights, which are concerned both with the protection of the individual child and with the creation of the conditions in which all children can develop to their full potential.” [1] The larger domains in which these rights are usurped are those related to education, health, neglect, abuse (physical, emotional, and sexual), corporal punishment, and child labour