3,450 research outputs found
Non-isothermal filaments in equilibrium
The physical properties of the so-called Ostriker isothermal filament
(Ostriker 1964) have been classically used as benchmark to interpret the
stability of the filaments observed in nearby clouds. However, recent continuum
studies have shown that the internal structure of the filaments depart from the
isothermality, typically exhibiting radially increasing temperature gradients.
The presence of internal temperature gradients within filaments suggests that
the equilibrium configuration of these objects should be therefore revisited.
The main goal of this work is to theoretically explore how the equilibrium
structure of a filament changes in a non-isothermal configuration. We solve the
hydrostatic equilibrium equation assuming temperature gradients similar to
those derived from observations. We obtain a new set of equilibrium solutions
for non-isothermal filaments with both linear and asymptotically constant
temperature gradients. Our results show that, for sufficiently large internal
temperature gradients, a non-isothermal filament could present significantly
larger masses per unit length and shallower density profiles than the
isothermal filament without collapsing by its own gravity. We conclude that
filaments can reach an equilibrium configuration under non-isothermal
conditions. Detailed studies of both the internal mass distribution and
temperature gradients within filaments are then needed in order to judge the
physical state of filaments.Comment: 5 pages, 2 figures, accepted for publication in A&
Status of the commissioning of ATLAS
The status of commissioning and readiness of the ATLAS experiment is reviewed, covering the installation of the last components, the test of the magnetic system, the combined runs with cosmic rays, the test of the computing system and the preparation for physics studies. The status of the detector with the first LHC beams in September 2008 is presented
Regional Organisations and Mechanisms for Democracy Protection in Latin America, the Caribbean and the European Union
Status of ATLAS commissioning
The readiness of ATLAS is presented, covering the last installation and integration operations, combined runs with cosmic rays, commissioning of the computing system and preparation for early physics, and discussing the status of the system at the start-up of LHC
Evolution of the Normal State of a Strongly Interacting Fermi Gas from a Pseudogap Phase to a Molecular Bose Gas
Wave-vector resolved radio frequency (rf) spectroscopy data for an ultracold
trapped Fermi gas are reported for several couplings at Tc, and extensively
analyzed in terms of a pairing-fluctuation theory. We map the evolution of a
strongly interacting Fermi gas from the pseudogap phase into a fully gapped
molecular Bose gas as a function of the interaction strength, which is marked
by a rapid disappearance of a remnant Fermi surface in the single-particle
dispersion. We also show that our theory of a pseudogap phase is consistent
with a recent experimental observation as well as with Quantum Monte Carlo data
of thermodynamic quantities of a unitary Fermi gas above Tc.Comment: 9 pages, 9 figures. Substantially revised version (to appear in Phys.
Rev. Lett.
THE PALLADIOLIBRARY GEO-MODELS: AN OPEN 3D ARCHIVE TO MANAGE AND VISUALIZE INFORMATION-COMMUNICATION RESOURCES ABOUT PALLADIO
Abstract. The paper describes objectives, methods, procedures and outcomes of the development of the digital archive of Palladio works and documentation: the PALLADIOLibrary of Centro Internazionale di Studi di Architettura Andrea Palladio di Vicenza (CISAAP). The core of the application consists of fifty-one reality-based 3D models usable and navigable within a system grounded on GoogleEarth. This information system, a collaboration of four universities bearers of specific skills returns a comprehensive, structured and coherent semantic interpretation of Palladian landscape through shapes realistically reconstructed from historical sources and surveys and treated for GE with Ambient Occlusion techniques, overcoming the traditional display mode
Pseudorapidity Distribution of Charged Particles in PbarP Collisions at root(s)= 630GeV
Using a silicon vertex detector, we measure the charged particle
pseudorapidity distribution over the range 1.5 to 5.5 using data collected from
PbarP collisions at root s = 630 GeV. With a data sample of 3 million events,
we deduce a result with an overall normalization uncertainty of 5%, and typical
bin to bin errors of a few percent. We compare our result to the measurement of
UA5, and the distribution generated by the Lund Monte Carlo with default
settings. This is only the second measurement at this level of precision, and
only the second measurement for pseudorapidity greater than 3.Comment: 9 pages, 5 figures, LaTeX format. For ps file see
http://hep1.physics.wayne.edu/harr/harr.html Submitted to Physics Letters
HISTONE DEACETYLASE INHIBITION AFFECTS SODIUM IODIDE SYMPORTER (NIS) EXPRESSION AND INDUCES ¹³¹I CYTOTOXICITY IN ANAPLASTIC THYROID CANCER CELLS.
Transverse Momentum Distributions for Heavy Quark Pairs
We study the transverse momentum distribution for a of heavy quarks
produced in hadron-hadron interactions. Predictions for the large transverse
momentum region are based on exact order QCD perturbation theory.
For the small transverse momentum region, we use techniques for all orders
resummation of leading logarithmic contributions associated with initial state
soft gluon radiation. The combination provides the transverse momentum
distribution of heavy quark pairs for all transverse momenta. Explicit results
are presented for pair production at the Fermilab Tevatron collider
and for pair production at fixed target energies.Comment: LaTeX (27 pages text, 8 figures not included, but available on
request
Shape-resonant superconductivity in nanofilms: from weak to strong coupling
Ultrathin superconductors of different materials are becoming a powerful
platform to find mechanisms for enhancement of superconductivity, exploiting
shape resonances in different superconducting properties. Here we evaluate the
superconducting gap and its spatial profile, the multiple gap components, and
the chemical potential, of generic superconducting nanofilms, considering the
pairing attraction and its energy scale as tunable parameters, from weak to
strong coupling, at fixed electron density. Superconducting properties are
evaluated at mean field level as a function of the thickness of the nanofilm,
in order to characterize the shape resonances in the superconducting gap. We
find that the most pronounced shape resonances are generated for weakly coupled
superconductors, while approaching the strong coupling regime the shape
resonances are rounded by a mixing of the subbands due to the large energy gaps
extending over large energy scales. Finally, we find that the spatial profile,
transverse to the nanofilm, of the superconducting gap acquires a flat behavior
in the shape resonance region, indicating that a robust and uniform multigap
superconducting state can arise at resonance.Comment: 7 pages, 4 figures. Submitted to the Proceedings of the Superstripes
2016 conferenc
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