389 research outputs found
Phase diagram at finite temperature and quark density in the strong coupling limit of lattice QCD for color SU(3)
We study the phase diagram of quark matter at finite temperature (T) and
finite chemical potential (mu) in the strong coupling limit of lattice QCD for
color SU(3). We derive an analytical expression of the effective free energy as
a function of T and mu, including baryon effects. The finite temperature
effects are evaluated by integrating over the temporal link variable exactly in
the Polyakov gauge with anti-periodic boundary condition for fermions. The
obtained phase diagram shows the first order phase transition at low
temperatures and the second order phase transition at high temperatures
separated by the tri-critical point in the chiral limit. Baryon has effects to
reduce the effective free energy and to extend the hadron phase to a larger mu
direction at low temperatures.Comment: 18 pages, 10 figure
Quadrupolar Kondo Effect in Non-Kramers Doublet System PrInAg2
We performed ultrasonic measurement on the rare-earth intermetallic compound
PrInAg_2 to examine the quadrupolar Kondo effect associated with the
non-Kramers Gamma_3 doublet ground state. The characteristic softening of the
elastic constant (c_{11}-c_{12})/2 below 10 K in PrInAg_2 is attributed to a
Curie term in quadrupolar susceptibility for the quadrupole O_2^2=J_x^2-J_y^2
of the stable Gamma_3 ground state. (c_{11}-c_{12})/2 turns to a slight
increase with the -lnT dependence below 0.1 K, which suggests the quenching of
the quadrupolar moment in the quadrupolar Kondo state. Under applied magnetic
fields of 10 T and 15 T above 8.7 T corresponding to the Kondo temperature T_K
of ~ 0.86 K, the behavior of (c_{11}-c_{12})/2 is described in terms of
quadrupolar susceptibility for the stable 4f^2 state.Comment: PDF, 10pages + 5figures, Strongly Correlated Electron
Quadrupole Susceptibility and Elastic Softening due to a Vacancy in Silicon Crystal
We investigate the electronic states around a single vacancy in silicon
crystal by using the Green's function approach. The triply degenerate vacancy
states within the band gap are found to be extended over a large distance
from the vacancy site and contribute to the reciprocal
temperature dependence of the quadrupole susceptibility resulting in the
elastic softening at low temperture. The Curie constant of the quadrupole
susceptibility for the trigonal mode () is largely
enhanced as compared to that for the tetragonal mode ().
The obtained results are consistent with the recent ultrasonic experiments in
silicon crystal down to 20 mK. We also calculate the dipole and octupole
susceptibilities and find that the octupole susceptibilities are extremely
enhannced for a specific mode.Comment: 6 pages, with 5 figure
Resonant X-Ray Scattering from URu_{2}Si_{2}
Based on a localized crystal electric field model for the U^{4+} in the
(5f)^2-configuration, we analyze the resonant x-ray scattering spectra around U
M_{IV} and M_{V} edges in URu_{2}Si_{2}, taking full Coulomb and spin-orbit
interactions into account. We consider two level schemes, a singlet model of
Santini and Amoretti and a doublet model of Ohkawa and Shimizu, and assume the
antiferroquadrupolar order and the antiferromagnetic order as candidates for
the ambient pressure phase and the high pressure phase. It is found that the
spectral shapes as a function of photon energy are independent of the assumed
level scheme, but are quite different between the antiferroquadrupole and
antiferromagnetic phases, This may be useful to determine the character of the
ordered phase.Comment: 8 pages, 5 figures, submitted to JPS
Methane budget estimates in Finland from the CarbonTracker Europe-CH4 data assimilation system
This is the final version. Available from the publisher via the DOI in this record.We estimated the CH4 budget in Finland for 2004–2014 using the CTE-CH4 data assimilation system with an extended atmospheric CH4 observation network of seven sites from Finland to surrounding regions (Hyytiälä, Kjølnes, Kumpula, Pallas, Puijo, Sodankylä, and Utö). The estimated average annual total emission for Finland is 0.6 ± 0.5 Tg CH4 yr−1. Sensitivity experiments show that the posterior biospheric emission estimates for Finland are between 0.3 and 0.9 Tg CH4 yr−1, which lies between the LPX-Bern-DYPTOP (0.2 Tg CH4 yr−1) and LPJG-WHyMe (2.2 Tg CH4 yr−1) process-based model estimates. For anthropogenic emissions, we found that the EDGAR v4.2 FT2010 inventory (0.4 Tg CH4 yr−1) is likely to overestimate emissions in southernmost Finland, but the extent of overestimation and possible relocation of emissions are difficult to derive from the current observation network. The posterior emission estimates were especially reliant on prior information in central Finland. However, based on analysis of posterior atmospheric CH4, we found that the anthropogenic emission distribution based on a national inventory is more reliable than the one based on EDGAR v4.2 FT2010. The contribution of total emissions in Finland to global total emissions is only about 0.13%, and the derived total emissions in Finland showed no trend during 2004–2014. The model using optimized emissions was able to reproduce observed atmospheric CH4 at the sites in Finland and surrounding regions fairly well (correlation > 0.75, bias < ± ppb), supporting adequacy of the observations to be used in atmospheric inversion studies. In addition to global budget estimates, we found that CTE-CH4 is also applicable for regional budget estimates, where small scale (1x1 in this case) optimization is possible with a dense observation network.Natural Environment Research Council (NERC)NordFrosk Nordic Centre of ExcellenceAcademy of FinlandEuropean Research Council (ERC)Swiss National Science Foundation (SNSF)Swedish Research Counci
Isolated neutron stars and studies of their interiors
In these lectures presented at Baikal summer school on physics of elementary
particles and astrophysics 2011, I present a wide view of neutron star
astrophysics with special attention paid to young isolated compact objects and
studies of the properties of neutron star interiors using astronomical methods.Comment: 28 pages, lecture notes for the Baikal-2011 summer school on physics
of elementary particles and astrophysic
Endoplasmic spreading requires coalescence of vimentin intermediate filaments at force-bearing adhesions
10.1091/mbc.E12-05-0377Molecular Biology of the Cell24121-30MBCE
Pairing in nuclear systems: from neutron stars to finite nuclei
We discuss several pairing-related phenomena in nuclear systems, ranging from
superfluidity in neutron stars to the gradual breaking of pairs in finite
nuclei. We focus on the links between many-body pairing as it evolves from the
underlying nucleon-nucleon interaction and the eventual experimental and
theoretical manifestations of superfluidity in infinite nuclear matter and of
pairing in finite nuclei. We analyse the nature of pair correlations in nuclei
and their potential impact on nuclear structure experiments. We also describe
recent experimental evidence that points to a relation between pairing and
phase transitions (or transformations) in finite nuclear systems. Finally, we
discuss recent investigations of ground-state properties of random two-body
interactions where pairing plays little role although the interactions yield
interesting nuclear properties such as 0+ ground states in even-even nuclei.Comment: 74 pages, 33 figs, uses revtex4. Submitted to Reviews of Modern
Physic
Orbital effects of a monochromatic plane gravitational wave with ultra-low frequency incident on a gravitationally bound two-body system
We analytically compute the long-term orbital variations of a test particle
orbiting a central body acted upon by an incident monochromatic plane
gravitational wave. We assume that the characteristic size of the perturbed
two-body system is much smaller than the wavelength of the wave. Moreover, we
also suppose that the wave's frequency is much smaller than the particle's
orbital one. We make neither a priori assumptions about the direction of the
wavevector nor on the orbital geometry of the planet. We find that, while the
semi-major axis is left unaffected, the eccentricity, the inclination, the
longitude of the ascending node, the longitude of pericenter and the mean
anomaly undergo non-vanishing long-term changes. They are not secular trends
because of the slow modulation introduced by the tidal matrix coefficients and
by the orbital elements themselves. They could be useful to indepenedently
constrain the ultra-low frequency waves which may have been indirectly detected
in the BICEP2 experiment. Our calculation holds, in general, for any
gravitationally bound two-body system whose characteristic frequency is much
larger than the frequency of the external wave. It is also valid for a generic
perturbation of tidal type with constant coefficients over timescales of the
order of the orbital period of the perturbed particle.Comment: LaTex2e, 24 pages, no figures, no tables. Changes suggested by the
referees include
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