555 research outputs found
Inclusive Muon Capture in Light Nuclei
We study total muon capture rates in light nuclei, taking into account
renormalizations of the nuclear vector and axial vector strengths. We estimate
the influence in the results of uncertainties of the spin-isospin interaction
parameter and nuclear densities. A few of these reactions are theoretical
benchmarks for physics involving searches for neutrino oscillations. New
experiments in muon capture in several targets are suggested, in the light of
some discrepancies with theory, crudeness of some experimental results and
relevance to neutrino physics.Comment: 11 pages, Latex, no figures. Submitted to Phys.Lett.
Indirect Evidences of Wildlife Activities in Shoals of Western Ghats, a Biodiversity Hotspots
The presence of wildlife fauna and its activities were ascertained with the density of the scat, dung and other markings or droppings of the wildlife abode therein. Attempt was made to find out spatial differences in the activities of the wildlife populations and to comment on the abundance of different preys and predators within shola forests of Western Ghat hill forests, a Biodiversity hotspot in India. An indirect sampling method, Transect Count Method, was employed to count dung/pellet group/scat and other markings in that area. Pachyderms were found to be mostly dominant in Varagaliar and Punnumala shola patches while scats of all the three important predators, viz., tiger (Panthera tigris tigris), Indian wild dog (Cuon alpinus) and leopard (Panthera pardus) were encountered only in Varagaliar shola. Greater abundance was recorded from Indira Gandhi Wildlife Sanctuary than Silent Valley National Park may be because of the restriction of animal movements in the former due to topographical barriers and its existence as isolated shola patches that led to a greater concentration of wild fauna in a relatively segregated forest coverΠΡΠΈΡΡΡΡΡΠ²ΠΈΠ΅ ΠΎΡΠ³Π°Π½ΠΈΠ·ΠΌΠΎΠ² Π² ΠΏΡΠΈΡΠΎΠ΄Π½ΠΎΠΉ ΡΡΠ΅Π΄Π΅ ΠΈ ΠΈΡ
ΠΆΠΈΠ·Π½Π΅Π΄Π΅ΡΡΠ΅Π»ΡΠ½ΠΎΡΡΡ Π±ΡΠ»ΠΈ ΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½Ρ ΠΏΠΎ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΡΠ°ΡΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΡΠΊΡΠΊΡΠ΅ΠΌΠ΅Π½ΡΠΎΠ² ΠΈ Π΄ΡΡΠ³ΠΈΡ
ΠΌΠ΅ΡΠΎΠΊ ΠΆΠΈΠ²ΠΎΡΠ½ΡΡ
Π² ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Π½ΡΡ
ΠΌΠ΅ΡΡΠ°Ρ
. ΠΡΠ»ΠΈ ΡΠ΄Π΅Π»Π°Π½Ρ ΠΏΠΎΠΏΡΡΠΊΠΈ Π½Π°ΠΉΡΠΈ ΠΎΡΠ»ΠΈΡΠΈΡ Π² ΠΆΠΈΠ·Π½Π΅Π΄Π΅ΡΡΠ΅Π»ΡΠ½ΠΎΡΡΠΈ ΠΏΠΎΠΏΡΠ»ΡΡΠΈΠΉ Π΄ΠΈΠΊΠΈΡ
ΠΆΠΈΠ²ΠΎΡΠ½ΡΡ
, ΠΈ ΠΏΡΠΎΠΊΠΎΠΌΠΌΠ΅Π½ΡΠΈΡΠΎΠ²Π°ΡΡ ΠΌΠ½ΠΎΠ³ΠΎΠΎΠ±ΡΠ°Π·ΠΈΠ΅ Ρ
ΠΈΡΠ½ΠΈΠΊΠΎΠ² ΠΈ ΠΈΡ
ΠΆΠ΅ΡΡΠ² Π² Π»Π΅ΡΠ°Ρ
ΡΠΎΠ»Π°, ΠΌΠ΅ΡΡΠ°Ρ
Π½Π°ΠΈΠ±ΠΎΠ»ΡΡΠ΅Π³ΠΎ Π±ΠΈΠΎΡΠ°Π·Π½ΠΎΠΎΠ±ΡΠ°Π·ΠΈΡ Π² ΠΠ½Π΄ΠΈΠΈ. ΠΠ΅ΡΠΎΠ΄ ΠΊΠΎΡΠ²Π΅Π½Π½ΡΡ
ΠΎΠ±ΡΠ°Π·ΡΠΎΠ² ΠΈ ΠΌΠ΅ΡΠΎΠ΄ ΡΡΠ°Π½ΡΠ΅ΠΊΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΠ΄ΡΡΠ΅ΡΠ° Π±ΡΠ»ΠΈ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½Ρ Π΄Π»Ρ ΠΏΠΎΠ΄ΡΡΠ΅ΡΠ° ΡΠΊΡΠΊΡΠ΅ΠΌΠ΅Π½ΡΠΎΠ²/ΠΏΠΎΠ³Π°Π΄ΠΎΠΊ ΠΈ Π΄ΡΡΠ³ΠΈΡ
ΠΌΠ΅ΡΠΎΠΊ Π² ΠΈΡΡΠ»Π΅Π΄ΡΠ΅ΠΌΠΎΠΌ ΡΠ΅Π³ΠΈΠΎΠ½Π΅. Π£ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ Π½Π° Π½Π΅Π±ΠΎΠ»ΡΡΠΈΡ
ΡΡΠ°ΡΡΠΊΠ°Ρ
Π·Π΅ΠΌΠ»ΠΈ Π² ΡΠΎΠ»Π° ΠΠ°ΡΠ°Π³Π°Π»ΠΈΠ°Ρ ΠΈ ΠΡΠ½Π½ΡΠΌΠ°Π»Π° Π΄ΠΎΠΌΠΈΠ½ΠΈΡΡΡΡ ΡΠΎΠ»ΡΡΠΎΠΊΠΎΠΆΠΈΠ΅, ΡΠΎΠ³Π΄Π° ΠΊΠ°ΠΊ ΡΠΊΡΠΊΡΠ΅ΠΌΠ΅Π½ΡΡ Ρ
ΠΈΡΠ½ΠΈΠΊΠΎΠ² β ΡΠΈΠ³ΡΠ° (Panthera tigris tigris), ΠΊΡΠ°ΡΠ½ΠΎΠ³ΠΎ Π²ΠΎΠ»ΠΊΠ° (Cuon alpinus) ΠΈ Π»Π΅ΠΎΠΏΠ°ΡΠ΄Π° (Panthera pardus) β Π±ΡΠ»ΠΈ ΡΠ»ΡΡΠ°ΠΉΠ½ΠΎ ΠΎΠ±Π½Π°ΡΡΠΆΠ΅Π½Ρ ΡΠΎΠ»ΡΠΊΠΎ Π² ΡΠΎΠ»Π° ΠΠ°ΡΠ°Π³Π°Π»ΠΈΠ°Ρ. ΠΠ½Π°ΡΠΈΡΠ΅Π»ΡΠ½ΠΎ Π±ΠΎΠ»ΡΡΠ΅Π΅ ΠΊΠΎΠ»ΠΈΡΠ΅ΡΡΠ²ΠΎ Π±ΡΠ»ΠΎ Π·Π°ΡΠ΅Π³ΠΈΡΡΡΠΈΡΠΎΠ²Π°Π½ΠΎ Π² ΠΠ°ΠΏΠΎΠ²Π΅Π΄Π½ΠΈΠΊΠ΅ Π΄ΠΈΠΊΠΎΠΉ ΠΏΡΠΈΡΠΎΠ΄Ρ ΠΈΠΌ. ΠΠ½Π΄ΠΈΡΡ ΠΠ°Π½Π΄ΠΈ ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Ρ ΠΠ°ΡΠΈΠΎΠ½Π°Π»ΡΠ½ΡΠΌ ΠΏΠ°ΡΠΊΠΎΠΌ Β«Π’ΠΈΡ
Π°Ρ ΠΠΎΠ»ΠΈΠ½Π°Β», Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎ, ΠΈΠ·-Π·Π° ΠΎΠ³ΡΠ°Π½ΠΈΡΠ΅Π½ΠΈΡ ΠΌΠΈΠ³ΡΠ°ΡΠΈΠΉ ΠΆΠΈΠ²ΠΎΡΠ½ΡΡ
ΡΠΎΠΏΠΎΠ³ΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈ Π±Π°ΡΡΠ΅ΡΠ°ΠΌΠΈ Π² ΠΏΡΠΎΡΠ»ΠΎΠΌ, ΡΡΠΎ ΠΏΡΠΈΠ²Π΅Π»ΠΎ ΠΊ Π±ΠΎΠ»ΡΡΠ΅ΠΉ ΠΊΠΎΠ½ΡΠ΅Π½ΡΡΠ°ΡΠΈΠΈ Π΄ΠΈΠΊΠΎΠΉ ΡΠ°ΡΠ½Ρ Π² ΠΎΡΠ½ΠΎΡΠΈΡΠ΅Π»ΡΠ½ΠΎ ΠΎΠ±ΠΎΡΠΎΠ±Π»Π΅Π½Π½ΠΎΠΌ Π»Π΅ΡΡ
Measurement of the Interior Structure of Thin Polymer Films Using Grazing Incidence Diffuse X-Ray Scattering
A method is developed for calculating the small-angle x-ray scattering originating from within the interior of
a thin film under grazing incidence illumination. This offers the possibility of using x-ray scattering to probe
how the structure of polymers is modified by confinement. When the diffuse scattering from a thin film is
measured over a range of incident angles, it is possible to separate the contributions to scattering from the
interfaces and the contribution from the film interior. Using the distorted-wave Born approximation the structure
factor, S q , of the film interior can then be obtained. We apply this method to analyze density fluctuations
from within the interior of a silicon supported molten polystyrene PS film. Measurements were made as a
function of film thickness ranging from one to ten times the polymer radius of gyration Rg . The compressibility,
calculated by extrapolating the measured S q to q=0, agrees well with that of bulk PS for thick films,
but thinner films exhibit a peak in S q near q=0. This peak, which grows with decreasing thickness, is
attributed to a decreased interpenetration of chains and a consequent enhanced compressibility.This work is
supported by NSF Grant No. DMR-0209542. Use of the Advanced
Photon Source at Argonne National Laboratory was
supported by U.S. Department of Energy, Office of Science,
Office of Basic Energy Sciences, under DOE Contract
No. DE-AC02-06CH11357
Stochastic dynamic stability analysis of composite curved panels subjected to non-uniform partial edge loading
The stochastic dynamic stability analysis of laminated composite curved panels under non-uniform partial edge loading is studied using finite element analysis. The system input parameters are randomized to ascertain the stochastic first buckling load and zone of resonance. Considering the effects of transverse shear deformation and rotary inertia, first order shear deformation theory is used to model the composite doubly curved shells. The stochasticity is introduced in Love's and Donnell's theory considering dynamic and shear deformable theory according to the Sander's first approximation by tracers for doubly curved laminated shells. The moving least square method is employed as a surrogate of the actual finite element model to reduce the computational cost. The results are compared with those available in the literature. Statistical results are presented to show the effects of radius of curvatures, material properties, fibre parameters, and non-uniform load parameters on the stability boundaries
Spin 0 and spin 1/2 particles in a spherically symmetric static gravity and a Coulomb field
A relativistic particle in an attractive Coulomb field as well as a static
and spherically symmetric gravitational field is studied. The gravitational
field is treated perturbatively and the energy levels are obtained for both
spin 0 (Klein-Gordon) and spin 1/2 (Dirac) particles. The results are shown to
coincide with each other as well as the result of the nonrelativistic
(Schrodinger) equation in the nonrelativistic limit.Comment: 12 page
Reaction and Axial Vector Coupling
The reaction is studied in the region of low
to investigate the effect of deuteron structure and width of the
resonance on the differential cross section. The results are used to extract
the axial vector coupling from the experimental data on
this reaction. The possibility to determine this coupling from electroweak
interaction experiments with high intensity electron accelerators is discussed.Comment: 14 pages, REVTEX, 5 figure
Fractional two-branes, toric orbifolds and the quantum McKay correspondence
We systematically study and obtain the large-volume analogues of fractional
two-branes on resolutions of orbifolds C^3/Z_n. We study a generalisation of
the McKay correspondence proposed in hep-th/0504164 called the quantum McKay
correspondence by constructing duals to the fractional two-branes. Details are
explicitly worked out for two examples -- the crepant resolutions of C^3/Z_3
and C^3/Z_5.Comment: 34 pages, 2 figures, LaTeX (JHEP3 style); (v2) typos corrected; (v3)
sec 3 reorganise
Fractional Branes in Non-compact Type IIA Orientifolds
We study fractional D-branes in the Type-IIA theory on a non-compact
orientifold of the orbifold C^3/Z_3 in the boundary state formalism. We find
that the fractional D0-branes of the orbifold theory become unstable due to the
presence of a tachyon, while there is a stable D-instanton whose tachyon gets
projected out. We propose that the D-instanton is obtained after tachyon
condensation. We evidence this by calculating the Whitehead group of the
Abelian category of objects corresponding to the boundary states as being
isomorphic to Z_2.Comment: 29 pages, Latex2e minor corrections. references updated. Version
accepted in JHE
A quantum McKay correspondence for fractional 2p-branes on LG orbifolds
We study fractional 2p-branes and their intersection numbers in non-compact
orbifolds as well the continuation of these objects in Kahler moduli space to
coherent sheaves in the corresponding smooth non-compact Calabi-Yau manifolds.
We show that the restriction of these objects to compact Calabi-Yau
hypersurfaces gives the new fractional branes in LG orbifolds constructed by
Ashok et. al. in hep-th/0401135. We thus demonstrate the equivalence of the
B-type branes corresponding to linear boundary conditions in LG orbifolds,
originally constructed in hep-th/9907131, to a subset of those constructed in
LG orbifolds using boundary fermions and matrix factorization of the
world-sheet superpotential. The relationship between the coherent sheaves
corresponding to the fractional two-branes leads to a generalization of the
McKay correspondence that we call the quantum McKay correspondence due to a
close parallel with the construction of branes on non-supersymmetric orbifolds.
We also provide evidence that the boundary states associated to these branes in
a conformal field theory description corresponds to a sub-class of the boundary
states associated to the permutation branes in the Gepner model associated with
the LG orbifold.Comment: LaTeX2e, 1+39 pages, 3 figures (v2) refs added, typos and report no.
correcte
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