403 research outputs found
Geophysical Research
Contains reports on two research projects.National Aeronautics and Space Administration (Grant NGR-22-009-131)National Aeronautics and Space Administration (Grant NGR-22-009-114)National Aeronautics and Space Administration (Contract NAS 12-436
Congenital tumors and nonimmune hydrops fetalis
Peer Reviewe
Universal behavior of multiplicity differences in quark-hadron phase transition
The scaling behavior of factorial moments of the differences in
multiplicities between well separated bins in heavy-ion collisions is proposed
as a probe of quark-hadron phase transition. The method takes into account some
of the physical features of nuclear collisions that cause some difficulty in
the application of the usual method. It is shown in the Ginzburg-Landau theory
that a numerical value of the scaling exponent can be determined
independent of the parameters in the problem. The universality of
characterizes quark-hadron phase transition, and can be tested directly by
appropriately analyzed data.Comment: 15 pages, including 4 figures (in epsf file), Latex, submitted to
Phys. Rev.
A Color Mutation Model of Soft Interaction in High Energy Hadronic Collisions
A comprehensive model, called ECOMB, is proposed to describe multiparticle
production by soft interaction. It incorporates the eikonal formalism, parton
model, color mutation, branching and recombination. The physics is conceptually
opposite to the dynamics that underlies the fragmentation of a string. The
partons are present initially in a hadronic collision; they form a single,
large, color-neutral cluster until color mutation of the quarks leads to a
fission of the cluster into two color-neutral subclusters. The mutation and
branching processes continue until only pairs are left in each small
cluster. The model contains self-similar dynamics and exhibits scaling behavior
in the factorial moments. It can satisfactorily reproduce the intermittency
data that no other model has been able to fit.Comment: 24 pages including 11 figures in revtex epsf styl
Modified Gravity on the Brane and Dark Energy
We analyze the dynamics of an AdS5 braneworld with matter fields when gravity
is allowed to deviate from the Einstein form on the brane. We consider exact
5-dimensional warped solutions which are associated with conformal bulk fields
of weight -4 and describe on the brane the following three dynamics: those of
inhomogeneous dust, of generalized dark radiation, and of homogeneous
polytropic dark energy. We show that, with modified gravity on the brane, the
existence of such dynamical geometries requires the presence of non-conformal
matter fields confined to the brane.Comment: Revised version published in Gen. Rel. Grav. Typos corrected, updated
reference and some remarks added for clarity. 11 pages, latex, no figure
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Search for MSSM Higgs bosons decaying to μ+μ-in proton-proton collisions at √s=13TeV
A search is performed for neutral non-standard-model Higgs bosons decaying to two muons in the context of the minimal supersymmetric standard model (MSSM). Proton-proton collision data recorded by the CMS experiment at the CERN Large Hadron Collider at a center-of-mass energy of 13TeVwere used, corresponding to an integrated luminosity of 35.9fb-1. The search is sensitive to neutral Higgs bosons produced via the gluon fusion process or in association with a bbquark pair. No significant deviations from the standard model expectation are observed. Upper limits at 95% confidence level are set in the context of the mmod+hand phenomenological MSSM scenarios on the parameter tanβas a function of the mass of the pseudoscalar Aboson, in the range from 130 to 600GeV. The results are also used to set a model-independent limit on the product of the branching fraction for the decay into a muon pair and the cross section for the production of a scalar neutral boson, either via gluon fusion, or in association with bquarks, in the mass range from 130 to 1000GeV
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