Abundances in the Uranium-Rich Star CS 31082-001

The recent discovery by Cayrel et al. of U in CS 31082-001 along with Os and Ir at greatly enhanced abundances but with [Fe/H]=-2.9 strongly reinforces the argument that there are at least two kinds of SNII sources for r-nuclei. One source is the high-frequency H events responsible for heavy r-nuclei (A>135) but not Fe. The H-yields calculated from data on other ultra-metal-poor stars and the sun provide a template for quantitatively predicting the abundances of all other r-elements. In CS 31082-001 these should show a significant deficiency at A<135 relative to the solar r-pattern. It is proposed that CS 31082-001 should have had a companion that exploded as an SNII H event. If the binary survived the explosion, this star should now have a compact companion, most likely a stellar-mass black hole. Comparison of abundance data with predicted values and a search for a compact companion should provide a stringent test of the proposed r-process model. The U-Th age determined by Cayrel et al. for CS 31082-001 is, to within substantial uncertainties, in accord with the r-process age determined from solar system data. The time gap between Big Bang and onset of normal star formation only allows r-process chronometers to provide a lower limit on the age of the universe.Comment: 5 pages, 1 figur

SS Ari: a shallow-contact close binary system

Two CCD epochs of light minimum and a complete R light curve of SS Ari are presented. The light curve obtained in 2007 was analyzed with the 2003 version of the W-D code. It is shown that SS Ari is a shallow contact binary system with a mass ratio $q=3.25$ and a degree of contact factor f=9.4(\pm0.8%). A period investigation based on all available data shows that there may exist two distinct solutions about the assumed third body. One, assuming eccentric orbit of the third body and constant orbital period of the eclipsing pair results in a massive third body with $M_3=1.73M_{\odot}$ and P_3=87.0$yr. On the contrary, assuming continuous period changes of the eclipsing pair the orbital period of tertiary is 37.75yr and its mass is about$0.278M_{\odot}$. Both of the cases suggest the presence of an unseen third component in the system.Comment: 28 pages, 9 figures and 5 table

High Fill-Out, Extreme Mass Ratio Overcontact Binary Systems. X. The new discovered binary XY Leonis Minoris

The new discovered short-period close binary star, XY LMi, was monitored photometrically since 2006. It is shown that the light curves are typical EW-type and show complete eclipses with an eclipse duration of about 80 minutes. By analyzing the complete B, V, R, and I light curves with the 2003 version of the W-D code, photometric solutions were determined. It is discovered that XY LMi is a high fill-out, extreme mass ratio overcontact binary system with a mass ratio of q=0.148 and a fill-out factor of f=74.1%, suggesting that it is on the late evolutionary stage of late-type tidal-locked binary stars. As observed in other overcontact binary stars, evidence for the presence of two dark spots on both components are given. Based on our 19 epoches of eclipse times, it is found that the orbital period of the overcontact binary is decreasing continuously at a rate of dP/dt=-1.67\times10^{-7}\,days/year, which may be caused by the mass transfer from the primary to the secondary or/and angular momentum loss via magnetic stellar wind. The decrease of the orbital period may result in the increase of the fill-out, and finally, it will evolve into a single rapid-rotation star when the fluid surface reaching the outer critical Roche Lobe.Comment: 19 pages, 4 figures, 9 table

Kinematics and flux evolution of superluminal components in QSO B1308+326

Search for Doppler-boosting effect in flux evolution of superluminal components in blazars has been an important subject, which can help clarify their kinematic and emission properties. The kinematics and flux evolution observed at 15GHz for the three superluminal components (knot-c, -i and -k) in QSO B1308+326 (z=0.997) were investigated in detail. It is shown that the precessing jet nozzle model previously proposed by Qian et al. (1991, 2014, 2017, 2022a, 2022b) can be used to fully simulate their kinematics on pc-scales with a nozzle precession period of 16.9 yr. With the acceleration/deceleration in their motion found in the model-simulation of their kinematics we can derive their bulk Lorentz factor and Doppler factor as function of time and predict their Doppler-boosting effect. Interestingly, the flux evolution of the three superluminal components can be well interpreted in terms of their Doppler-boosting effect. The full explanation of both their kinematic behavior and flux evolution validates our precessing nozzle model and confirms that superluminal components are physical entities moving relativistically toward us at small viewing angles.Comment: 13 pages, 41 figure

Flux evolution and kinematics of superluminal components in blazar 3C345

The precessing jet-nozzle scenario previously proposed was applied to model-fit the kinematics of five superluminal components (C19,C20,C21,B5 and B7) of jet-B in blazar 3C345. Based on a specific pattern for the the precessing common trajectory of jet-B, the kinematic properties (including trajectory,coordinates, core separation and apparent velocity) were model-fitted and their flux evolution could be studied. Through model-simulation of their kinematic behavior, the bulk Lorentz factor, viewing angle and Doppler factor were derived as continuous functions of time and the association of their flux evolution with their Doppler-boosting effect was investigated. The 43GHz light-curves of the five superluminal components can be well interpreted in terms of their Doppler effect. The close association of their flux evolution with the Doppler-boosting effect firmly validates our precessing nozzle scenario and supports the traditional point-view that superluminal components are physical entities (traveling shocks or plasmoids) participating relativistic motion toward us at small angles. The model-simulation of kinematic behavior of superluminal components by using our precessing nozzle scenario with specific patterns (helical or ballistic) assumed for the precessing common trajectories yields the model-derived bulk Lorentz factor, apparent velocity, viewing angle and Doppler factor as continuous functions of time, which are most applicable to study the connection of flux evolution with Doppler boosting effect for the superluminal components.Comment: 18 pages and 63 figure

Relative Entropy: Free Energy Associated with Equilibrium Fluctuations and Nonequilibrium Deviations

Using a one-dimensional macromolecule in aqueous solution as an illustration, we demonstrate that the relative entropy from information theory, $\sum_k p_k\ln(p_k/p_k^*)$, has a natural role in the energetics of equilibrium and nonequilibrium conformational fluctuations of the single molecule. It is identified as the free energy difference associated with a fluctuating density in equilibrium, and is associated with the distribution deviate from the equilibrium in nonequilibrium relaxation. This result can be generalized to any other isothermal macromolecular systems using the mathematical theories of large deviations and Markov processes, and at the same time provides the well-known mathematical results with an interesting physical interpretations.Comment: 5 page