4,557 research outputs found
Gridding of near vertical unrectified space photographs
Gridding of near vertical unrectified space photograph
The Influence of Reaction Rates on the Final p-Abundances
The astrophysical p-process is responsible for the origin of the proton rich
nuclei,which are heavier than iron. A huge network involving thousands of
reaction rates is necessary to calculate the final p-abundances. But not all
rates included in the network have a strong influence on the p-nuclei
abundances. The p-process was investigated using a full nuclear reaction
network for a type II supernovae explosion when the shock front passes through
the O/Ne layer. Calculations were done with a multi-layer model adopting the
seed of a pre-explosion evolution of a 25 mass star. In extensive simulations
we investigated the impact of single reaction rates on the final p-abundances.
The results are important for the strategy of future experiments in this field.Comment: 4 page
An overview of the communications technology satellite project: Executive summary
An overview of the Communications Technology Satellite (CTS) project, a joint venture between NASA and the Canadian Department of Communications is given. A brief technical description of the CTS spacecraft and its cognate hardware and operations, a history of the CTS project, and a list of the CTS experiments and demonstrations conducted during the course of the project are given
Effect of resonance decays on hadron elliptic flows
The influence of resonance decays on the elliptic flows of stable hadrons is
studied in the quark coalescence model. Although difference between the
elliptic flow of pions from resonance decays, except the rho meson, and that of
directly produced pions is appreciable, those for other stable hadrons are
small. Since there are more pions from the decays of rho mesons than from other
resonances, including resonance decays can only account partially the deviation
of final pion elliptic flow from the observed scaling of hadron elliptic flows,
i.e., the hadron elliptic flow per quark is the same at same transverse
momentum per quark. The remaining deviation can be explained by including the
effect due to the quark momentum distribution inside hadrons.Comment: 13 pages and 5 figures, version pubblished in PRC, updated references
and figure
Trionic phase of ultracold fermions in an optical lattice: A variational study
To investigate ultracold fermionic atoms of three internal states (colors) in
an optical lattice, subject to strong attractive interaction, we study the
attractive three-color Hubbard model in infinite dimensions by using a
variational approach. We find a quantum phase transition between a
weak-coupling superconducting phase and a strong-coupling trionic phase where
groups of three atoms are bound to a composite fermion. We show how the
Gutzwiller variational theory can be reformulated in terms of an effective
field theory with three-body interactions and how this effective field theory
can be solved exactly in infinite dimensions by using the methods of dynamical
mean field theory.Comment: 14 PRB pages, 8 figure
A chiral crystal in cold QCD matter at intermediate densities?
The analogue of Overhauser (particle-hole) pairing in electronic systems
(spin-density waves with non-zero total momentum ) is analyzed in
finite-density QCD for 3 colors and 2 flavors, and compared to the
color-superconducting BCS ground state (particle-particle pairing, =0). The
calculations are based on effective nonperturbative four-fermion interactions
acting in both the scalar diquark as well as the scalar-isoscalar quark-hole
('') channel. Within the Nambu-Gorkov formalism we set up the coupled
channel problem including multiple chiral density wave formation, and evaluate
the resulting gaps and free energies. Employing medium-modified
instanton-induced 't Hooft interactions, as applicable around
GeV (or 4 times nuclear saturation density), we find the 'chiral crystal phase'
to be competitive with the color superconductor.Comment: 14 pages ReVTeX, including 11 ps-/eps-figure
Interpretation of Recent SPS Dilepton Data
We summarize our current theoretical understanding of in-medium properties of
the electromagnetic current correlator in view of recent dimuon data from the
NA60 experiment in In(158 AGeV)-In collisions at the CERN-SPS. We discuss the
sensitivity of the results to space-time evolution models for the hot and dense
partonic and hadronic medium created in relativistic heavy-ion collisions and
the contributions from different sources to the dilepton-excess spectra.Comment: To appear in the proceedings of the 19th International Conference on
Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter 2006) v2:
references added, minor typos correcte
High back mutation rate in homo-allelic crosses of asco
High back mutation rate in homo-allelic crosses of asc
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