Hadron-hadron correlations at low and high pTp_T in heavy-ion collisions

The modification of two particle correlations within a jet due to its propagation through dense strongly interacting matter is explored. Different properties of the medium may be probed by varying the momentum of the detected hadrons. Very high transverse momentum ($p_T$) correlations sample the gluon density of the medium; the minimal modification on the same side as the trigger is consistent with the picture and parameters of partonic energy loss. Lower momentum hadrons, sensitive to the presence of composite structures in the medium may excite collective modes such as Cherenkov radiation, resulting in conical patterns in the detected correlations.Comment: 4 pages, 4 figures, Latex. To appear in the proceedings of the International Conference on Strong & Electroweak Matter 2006, Brookhaven National Laboratory, May 10-13, 200

Jet Quenching: the medium modification of the single and double fragmentation functions

The physics of the quenching of hard jets in dense matter is briefly reviewed. This is presented within the framework of the partonic medium modification of the fragmentation functions. Modifications in both deeply inelastic scattering (DIS) off large nuclei and high-energy heavy-ion collisions are presented.Comment: 4 pages, 4 figures, Proceedings of the First Meeting of the APS Topical Group on Hadronic Physics, Fermilab, Batavia, Illinois, Oct 24-26, 200

Jet modification in the next decade: a pedestrian outlook

In this review, intended for non-specialists and beginners, we recount the current status of the theory of jet modification in dense matter. We commence with an outline of the "traditional" observables which may be calculated without recourse to event generators. These include single and double hadron suppression, nuclear modification factor versus reaction plane etc. All of these measurements are used to justify both the required underlying physical picture of jet modification as well as the final obtained values of jet transport coefficients. This is followed by a review of the more modern observables which have arisen with the ability to reconstruct full jets, and the challenges faced therein. This is followed by a preview of upcoming theoretical developments in the field and an outlook on how the interface between these developments, phenomenological improvements, and upcoming data will allow us to quantitatively determine properties of the medium which effect the modification of hard jets.Comment: 21 pages, 10 figure

Singularity Free Rainbow Universe

Isotropic quantum cosmological perfect fluid model is studied in the formalism of Rainbow gravity. It is found that the only surviving matter degree of freedom played the role of cosmic time. It is possible to find the wave packet naturally with a suitable choice of the Rainbow functions which resulted from the superposition of the wave functions of the Schr$\ddot{o}$dinger-Wheeler-deWitt equation. The many-worlds interpretation of quantum mechanics is applied to investigate the behavior of the scale factor and the behaviour is found to depend on the operator ordering. It is shown that the model in the Rainbow framework naturally avoids singularity and a bouncing non-singular universe is found.Comment: This essay received an honorable mention in the 2013 Essay Competition of the Gravity Research Foundatio

Study of Wgamma events at the CMS with 7 TeV LHC data

The measurement of the inclusive cross section for Wgamma production is presented based on 36/ pb of data acquired with the CMS detector from 7 TeV LHC collisions in 2010. Comparisons are made with the predictions of the standard model. The W bosons are identified through their leptonic decays to electrons and muons. The Wgamma cross section is sensitive to anomalous triple-gauge couplings and hence this measurement probes physics beyond the standard model.Comment: Proceedings of talk given at Rencontres de Moriond, EWK session, La Thuile, Italy, 2011, on behalf of the CMS collaboration. 5 pages, 4 figure

Quantum Rainbow Cosmological Model With Perfect Fluid

Isotropic quantum cosmological perfect fluid model is studied in the formalism of Rainbow gravity. It is found that the only surviving matter degree of freedom played the role of cosmic time. With the suitable choice of the Rainbow functions it is possible to find the wave packet naturally from the superposition of the wave functions of the Schr$\ddot{o}$dinger-Wheeler-deWitt equation. The many-worlds interpretation of quantum mechanics is applied to investigate the behavior of the scale factor and the behavior is found to depend on the operator ordering. It is shown that the model in the Rainbow framework may avoid singularity yielding a bouncing non-singular universe.Comment: To appear in Int. J. Mod. Phys. D. arXiv admin note: substantial text overlap with arXiv:1305.370