A general maximum entropy principle for self-gravitating perfect fluid

We consider a self-gravitating system consisting of perfect fluid with spherical symmetry. Using the general expression of entropy density, we extremize the total entropy $S$ under the constraint that the total number of particles is fixed. We show that extrema of $S$ coincides precisely with the relativistic Tolman-Oppenheimer-Volkoff (TOV) equation of hydrostatic equilibrium. Furthermore, we apply the maximum entropy principle to a charged perfect fluid and derive the generalized TOV equation. Our work provides a strong evidence for the fundamental relationship between general relativity and ordinary thermodynamics.Comment: 13 pages, no figure. The arguments have been improved so that the assumption p=p(\rho) is no longer neede

New tabulate genus Sutherlandia (Coelenterata, Anthozoa) from Pennsylvanian of Oklahoma and Kansas

8 p., 3 fig.http://paleo.ku.edu/contributions.htm

Identification of a Previously Unobserved Dissociative Ionization Pathway in Time-Resolved Photospectroscopy of the Deuterium Molecule

Citation: Cao, W., Laurent, G., Ben-Itzhak, I., & Cocke, C. L. (2015). Identification of a Previously Unobserved Dissociative Ionization Pathway in Time-Resolved Photospectroscopy of the Deuterium Molecule. Physical Review Letters, 114(11), 5. doi:10.1103/PhysRevLett.114.113001A femtosecond vacuum ultraviolet (VUV) pulse with high spectral resolution (< 200 meV) is selected from the laser-driven high order harmonics. This ultrafast VUV pulse is synchronized with an infrared (IR) laser pulse to study dissociative ionization in deuterium molecules. At a VUV photon energy of 16.95 eV, a previously unobserved bond-breaking pathway is found in which the dissociation direction does not follow the IR polarization. We interpret it as corresponding to molecules predissociating into two separated atoms, one of which is photoionized by the following IR pulse. A time resolved study allows us to determine the lifetime of the intermediate predissociation process to be about 1 ps. Additionally, the dissociative ionization pathways show high sensitivity to the VUV photon energy. As the VUV photon energy is blueshifted to 17.45 eV, the more familiar bond-softening channel is opened to compete with the newly discovered pathway. The interpretation of different pathways is supported by the energy sharing between the electron and nuclei

Increased net muscle protein balance in response to simultaneous and separate ingestion of carbohydrate and essential amino acids following resistance exercise

Relative to essential amino acids (EAAs), carbohydrate (CHO) ingestion stimulates a delayed response of net muscle protein balance (NBAL). We investigated if staggered ingestion of CHO and EAA would superimpose the response of NBAL following resistance exercise, thus resulting in maximal anabolic stimulation. Eight recreationally trained subjects completed 2 trials: combined (COMB - drink 1, CHO+EAA; drink 2, placebo) and separated (SEP - drink 1, CHO; drink 2, EAA) post-exercise ingestion of CHO and EAA. Drink 1 was administered 1 h following an acute exercise bout and was followed 1 h later by drink 2. A primed, continuous infusion of l-[ring-13C6]-phenylalanine was combined with femoral arteriovenous sampling and muscle biopsies for the determination of muscle protein kinetics. Arterial amino acid concentrations increased following ingestion of EAA in both conditions. No difference between conditions was observed for phenylalanine delivery to the leg (COMB: 167 &plusmn; 23 &mu;mol&middot;min-1&middot;(100 mL leg vol)-1 &times; 6 h; SEP: 167 &plusmn; 21 &mu;mol&middot;min-1&middot;(100 mL leg vol)-1 &times; 6 h, P &gt; 0.05). In the first hour following ingestion of the drink containing EAA, phenylalanine uptake was 50% greater for the SEP trial than the COMB trial. However, phenylalanine uptake was similar for COMB (110 &plusmn; 19 mg) and SEP (117 &plusmn; 24 mg) over the 6 h period. These data suggest that whereas separation of CHO and EAA ingestion following exercise may have a transient physiological impact on NBAL, this response is not reflected over a longer period. Thus, separation of CHO and EAA ingestion is unnecessary to optimize post-exercise muscle protein metabolism

Measurements Of Recoil Ion Longitudinal Momentum Transfer In Multiply Ionizing Collisions Of Fast Heavy Ions With Multielectron Targets

The longitudinal momentum transfer to the recoil ion in collisions of 1 MeV/amu bare F ions with Ne are resolved for final charge states of both projectile and recoil ions. We observe the recoil to be thrown backwards in electron-capture events, reflecting the physical impact of the electron translation factor. The size of the momentum transfer is in agreement with classical trajectory Monte Carlo calculations for low charge state recoil ions but not for high charge state recoil ions. © 1993 The American Physical Society

Velocity Dependence Of One- And Two-electron Processes In Intermediate-velocity Ar16++He Collisions

We report investigations of one- and two-electron processes in the collisions of 0.9-keV/u to 60-keV/u (vp=0.19-1.55 a.u.) Ar16+ ions with He targets. The cross sections for these processes were measured by observing the final charges of the Ar ions and the recoiling target ions in coincidence. The average Q values for the capture channels were determined by measuring the longitudinal momenta of the recoiling target ions. Single capture (SC) is the dominant process and is relatively independent of the projectile energy. The two-electron transfer-ionization (TI) process is the next largest and slowly increases with projectile energy. The Q values for both SC and TI decrease with increasing projectile energy. Our data thereby suggest that electrons are captured into less tightly bound states as the collision velocity is increased. Both double capture and single ionization are much smaller and fairly independent of the projectile energy. The energy independence of SI is somewhat surprising as our energy range spans the region of the target electron velocity where ionization would be expected to increase. Our analysis suggests that the ionization process is being suppressed by SC and TI processes. © 1993 The American Physical Society

Momentum Spectra of Electrons Rescattered from Rare-Gas Targets Following Their Extraction by One- and Two-Color Femtosecond Laser Pulses

We have used velocity-map imaging to measure the three-dimensional momenta of electrons rescattered from Xe and Ar following the liberation of the electrons from these atoms by 45 fs, 800 nm intense laser pulses. Strong structure in the rescattering region is observed in both angle and energy, and is interpreted in terms of quantitative rescattering (QRS) theory. Momentum images have also been taken with two-color (800 nm + 400 nm) pulses on Xe targets. A strong dependence of the spectra on the relative phase of the two colors is observed in the rescattering region. Interpretation of the phase dependence using both QRS theory and a full solution to the time-dependent Schrödinger equation shows that the rescattered electrons provide a much more robust method for determining the relative phase of the two colors than do the direct electrons

On the investigations of galaxy redshift periodicity

In this article we present a historical review of study of the redshift periodicity of galaxies, starting from the first works performed in the seventies of the twentieth century until the present day. We discuss the observational data and methods used, showing in which cases the discretization of redshifts was observed. We conclude that galaxy redshift periodisation is an effect which can really exist. We also discussed the redshift discretization in two different structures: the Local Group of galaxies and the Hercules Supercluster. Contrary to the previous studies we consider all galaxies which can be regarded as a structure member disregarding the accuracy of velocity measurements. We applied the power spectrum analysis using the Hann function for weighting, together with the jackknife error estimator. In both the structures we found weak effects of redshift periodisation.Comment: 10 pages, 4 figures, to be published in Part. and Nucl. Lett. 200

Orientation Dependence of the Ionization of CO and NO in an Intense Femtosecond Two-Color Laser Field

Two-color (800- and 400-nm) short (45-fs) linearly polarized pulses are used to ionize and dissociate CO and NO. The emission of Cq+, Nq+, and O⁺ fragments indicates that the higher ionization rate occurs when the peak electric field points from C to O in CO and from N to O in NO. This preferred direction is in agreement with that predicted by Stark-corrected strong-field-approximation calculations