16,280 research outputs found
EMPIRICAL ISSUES IN CROP REINSURANCE DECISIONS
This paper investigates the role of reinsurance in the managing the liquidity or reserve fund risks facing a crop insurer. Using 31 years of data, combined with Monte Carlo simulation the paper illustrates a mechanism for calculating reinsurance premiums and determining the post insurance risk profile. The insured event is over a range of loss ratios, and the focus of the paper is on reserve fund balances.Reinsurance, crop insurance, agricultural risks, Crop Production/Industries, Risk and Uncertainty,
Fragmentation Function in Non-Equilibrium QCD Using Closed-Time Path Integral Formalism
In this paper we implement Schwinger-Keldysh closed-time path integral
formalism in non-equilibrium QCD to the definition of Collins-Soper
fragmentation function. We consider a high p_T parton in QCD medium at initial
time t_0 with arbitrary non-equilibrium (non-isotropic) distribution function
f(\vec{p}) fragmenting to hadron. We formulate parton to hadron fragmentation
function in non-equilibrium QCD in the light-cone quantization formalism. It
may be possible to include final state interactions with the medium via
modification of the Wilson lines in this definition of the non-equilibrium
fragmentation function. This may be relevant to study hadron production from
quark-gluon plasma at RHIC and LHC.Comment: 15 pages latex, Accepted for Publication in European Physical Journal
Parton Production Via Vacuum Polarization
We discuss the production mechanism of partons via vacuum polarization during
the very early, gluon dominated phase of an ultrarelativistic heavy-ion
collision in the framework of the background field method of quantum
chromodynamics.Comment: 3 pages, Latex, 3 figures (eps), to be published in JPhysG, SQM2001
proceeding
Irreversibility of field-induced magnetostructural transition in NiCoMnSb shape memory alloy revealed by magnetization, transport and heat capacity studies
The effects of magnetic field on the martensitic transition have been studied
in Ni45Co5Mn38Sb12. We find a large field-induced irreversibility in this
system, as revealed by the field dependence of resistivity, magnetization, and
heat capacity data. At the critical temperature, the field-induced conversion
of the martensitic to austenite phase is not reversible under any field
variation. At this temperature any energy fluctuation induces nucleation and
growth of the equilibrium austenite phase at the expense of the metastable
martensitic phase and gets arrested. All these three measurements completely
rule out the coexistence of austenite and martensitic phases in the
irreversibility regime.Comment: 13 pages, 4 figure
Star Clusters in the Magellanic Clouds-1: Parameterisation and Classification of 1072 Clusters in the LMC
We have introduced a semi-automated quantitative method to estimate the age
and reddening of 1072 star clusters in the Large Magellanic Cloud (LMC) using
the Optical Gravitational Lensing Experiment (OGLE) III survey data. This study
brings out 308 newly parameterised clusters. In a first of its kind, the LMC
clusters are classified into groups based on richness/mass as very poor, poor,
moderate and rich clusters, similar to the classification scheme of open
clusters in the Galaxy. A major cluster formation episode is found to happen at
125 +- 25 Myr in the inner LMC. The bar region of the LMC appears prominently
in the age range 60 - 250 Myr and is found to have a relatively higher
concentration of poor and moderate clusters. The eastern and the western ends
of the bar are found to form clusters initially, which later propagates to the
central part. We demonstrate that there is a significant difference in the
distribution of clusters as a function of mass, using a movie based on the
propagation (in space and time) of cluster formation in various groups. The
importance of including the low mass clusters in the cluster formation history
is demonstrated. The catalog with parameters, classification, and cleaned and
isochrone fitted CMDs of 1072 clusters, which are available as online material,
can be further used to understand the hierarchical formation of clusters in
selected regions of the LMC.Comment: 19 pages, 19figures, published in MNRAS on August 16, 2016
Supplementary material is available in the MNRAS websit
Downward shift of infrared conductivity spectral weight at the DDW transition: role of anisotropy
We consider the motion of conductivity spectral weight at a
finite-temperature phase transition at which density-wave (DDW)
order develops. We show that there is a shift of spectral weight to higher
frequencies if the quasiparticle lifetime is assumed to be isotropic, but a
shift to lower frequencies if the quasiparticle lifetime is assumed to be
anisotropic. We suggest that this is consistent with recent experiments on the
pseudogap phase of the cuprate superconductors and, therefore, conclude that
the observation of a downward shift in the spectral weight at the pseudogap
temperature does not militate against the DDW theory of the pseudogap.Comment: 8 pages, 7 figures. Added reference
Renormalization Group Equation and QCD Coupling Constant in the Presence of SU(3) Chromo-Electric Field
We solve renormalization group equation in QCD in the presence of SU(3)
constant chromo-electric field E^a with arbitrary color index a=1,2,...8 and
find that the QCD coupling constant \alpha_s depends on two independent
casimir/gauge invariants C_1=[E^aE^a] and C_2=[d_{abc}E^aE^bE^c]^2 instead of
one gauge invariant C_1=[E^aE^a]. The \beta function is derived from the
one-loop effective action. This coupling constant may be useful to study hadron
formation from color flux tubes/strings at high energy colliders and to study
quark-gluon plasma formation at RHIC and LHC.Comment: 13 pages latex, 4 eps figs, Eur. Phys. J.
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