7,358 research outputs found
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 three dimensional fluid dynamics at next-to-leading twist
The modification of the single inclusive spectrum of high transverse momentum
() pions emanating from an ultra-relativistic heavy-ion collision is
investigated. The deconfined sector is modelled using a full three dimensional
(3-D) ideal fluid dynamics simulation. Energy loss of high partons and
the ensuing modification of their fragmentation is calculated within
perturbative QCD at next-to-leading twist, where the magnitude of the higher
twist contribution is modulated by the entropy density extracted from the 3-D
fluid dynamics simulation. The nuclear modification factor () for pions
with a GeV as a function of centrality as well as with respect to
the reaction plane is calculated. The magnitude of contributions to the
differential within small angular ranges, from various depths in the
dense matter is extracted from the calculation and demonstrate the correlation
of the length integrated density and the from a given depth. The
significance of the mixed and hadronic phase to the overall magnitude of energy
loss are explored.Comment: 5 pages, 4 figures, Revte
Signals of spinodal hadronization: strangeness trapping
If the deconfinement phase transformation of strongly interacting matter is
of first-order and the expanding chromodynamic matter created in a high-energy
nuclear collision enters the corresponding region of phase coexistence, a
spinodal phase separation might occur. The matter would then condense into a
number of separate blobs, each having a particular net strangeness that would
remain approximately conserved during the further evolution. We investigate the
effect that such `strangeness trapping' may have on strangeness-related
hadronic observables. The kaon multiplicity fluctuations are significantly
enhanced and thus provide a possible tool for probing the nature of the phase
transition experimentally.Comment: 15 pages, 11 eps figure
Universality in Fluid Domain Coarsening: The case of vapor-liquid transition
Domain growth during the kinetics of phase separation is studied following
vapor-liquid transition in a single component Lennard-Jones fluid. Results are
analyzed after appropriately mapping the continuum snapshots obtained from
extensive molecular dynamics simulations to a simple cubic lattice. For near
critical quench interconnected domain morphology is observed. A brief period of
slow diffusive growth is followed by a linear viscous hydrodynamic growth that
lasts for an extended period of time. This result is in contradiction with
earlier inclusive reports of late time growth exponent 1/2 that questions the
uniqueness of the non-equilibrium universality for liquid-liquid and
vapor-liquid transitions.Comment: 6 pages, 5 figure
Local electromagnetic properties of magnetic pnictides: A comparative study probed by NMR measurement
75As and 31P NMR studies are performed in PrCoAsO and NdCoPO respectively.
The Knight shift data in PrCoAsO indicate the presence of an antiferromagnetic
interaction between the 4f moments along the c axis in the ferromagnetic state
of Co 3d moments. We propose a possible spin structure in this system. The 75As
quadrupolar coupling constant, increases continuously with the decrease
of temperature and is found to vary linearly with the intrinsic spin
susceptibility, Kiso. This indicates a possibility of the presence of a
coupling between charge density and spin density fluctuations. Further, 31P NMR
Knight shift and spin lattice relaxation rate (1/T1) in the paramagnetic state
of NdCoPO indicate that the differences between LaCoPO and NdCoPO with SmCoPO
are due to the decrement of inter layer separation and not due to the moments
of 4f electrons. Nuclear spin lattice relaxation time (T1) in NdCoPO shows weak
anisotropy at 300 K. Using self consistent renormalization (SCR)theory of
itinerant ferromagnet, it is shown that in the ab plane, the spin fluctuations
are three dimensional ferromagnetic in nature. From SCR theory the important
spin fluctuation parameters (, , ) are evaluated. The
similarities and dissimilarities of the NMR results in As and P based systems,
with different rare earths have also been discussed.Comment: 18 pages,13 figures, accepted for publication in J. Phys. Condens.
Matte
Linkage mapping of quantitative trait loci in humans: an overview
In this article, we provide an overview of the different statistical procedures that have been developed for linkage mapping of quantitative trait loci. We outline the model assumptions, the data requirements and the underlying tests for linkage for the different methods
Baryonic Strangeness and Related Susceptibilities in QCD
The ratios of off-diagonal to diagonal conserved charge susceptibilities
e.g., chi_{BS}/chi_{S}, chi_{QS}/chi_{S}, related to the quark flavor
susceptibilities, have proven to be discerning probes of the flavor carrying
degrees of freedom in hot strongly interacting matter. Various constraining
relations between the different susceptibilities are derived based on the
Gell-Mann-Nishijima formula and the assumption of isospin symmetry. Using
generic models of deconfined matter and results form lattice QCD, it is
demonstrated that the flavor carrying degrees of freedom at a temperature above
1.5T_c are quark-like quasiparticles. A new observable related by isospin
symmetry to C_{BS} = -3chi_{BS}/chi_{S} and equal to it in the baryon free
regime is identified. This new observable, which is blind to neutral and
non-strange particles, carries the potential of being measured in relativistic
heavy-ion collisions.Comment: 12 pages, 5 figures, RevTex
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