Global Slim Accretion Disk Solutions Revisited

We show that there exists a maximal possible accretion rate, beyond which global slim disk solutions cannot be constructed because in the vertical direction the gravitational force would be unable to balance the pressure force to gather the accreted matter. The principle for this restriction is the same as that for the Eddington luminosity and the corresponding critical accretion rate, which were derived for spherical accretion by considering the same force balance in the radial direction. If the assumption of hydrostatic equilibrium is waived and vertical motion is included, this restriction may become even more serious as the value of the maximal possible accretion rate becomes smaller. Previous understanding in the literature that global slim disk solutions could stand for any large accretion rates is due to the overestimation of the vertical gravitational force by using an approximate potential. For accretion flows with large accretion rates at large radii, outflows seem unavoidable in order for the accretion flow to reduce the accretion rate and follow a global solution till the central black hole.Comment: Accepted by Ap

Slim disks around Kerr black holes revisited

We investigate stationary slim accretion disks around Kerr black holes. We construct a new numerical method based on the relaxation technique. We systematically cover the whole parameter space relevant to stellar mass X-ray binaries. We also notice some non-monotonic features in the disk structure, overlooked in previous studies.Comment: 12 pages, 11 figures. The relativistic slim accretion disk solutions have been published online at http://users.camk.edu.pl/as/slimdisk. An appendix containing the manual for the data available online has been added to the previous version of the pape

SLIM--An Early Work Revisited

An early, but at the time illuminating, piece of work on how to deal with a general, linearly coupled accelerator lattice is revisited. This work is based on the SLIM formalism developed in 1979-1981

Body dissatisfaction revisited : on the importance of implicit beliefs about actual and ideal body image

Body dissatisfaction (i.e., a negative attitude towards one’s own physical appearance) is assumed to originate from a perceived discrepancy between the actual physical appearance (i.e., actual body image) and the desired ideal state of the body (i.e., ideal body image). We assessed implicit beliefs about these two aspects of the body image independently using two Relational Responding Tasks (RRT) in a sample of participants who were either low or high in explicitly reported body dissatisfaction. As hypothesized, differences in body dissatisfaction exerted a differential influence on the two RRT scores. The implicit belief that one is thin was less pronounced in participants who were strongly dissatisfied with their body relative to participants who were more satisfied with their body. The implicit desire to be thin (i.e., thin ideal body image), in contrast, tended to be more pronounced in participants who exhibited a high degree of body dissatisfaction as compared to participants who exhibited a low degree of body dissatisfaction. Hierarchical regression analyses also revealed that the RRT scores were predictive of self-reported body dissatisfaction, even over and above the predictive validity of some (but not all) explicit predictors of body dissatisfaction that were included in the present study. More generally, these findings contribute to the empirical validation of the RRT as a measure of implicit beliefs in the context of body dissatisfaction

An analytic relation for the thickness of accretion flows

We take the vertical distribution of the radial and azimuthal velocity into account in spherical coordinates, and find that the analytic relation c_{s0}/(v_K \Theta) = [(\gamma -1)/(2\gamma)]^{1/2} is valid for both geometrically thin and thick accretion flows, where c_{s0} is the sound speed on the equatorial plane, v_K is the Keplerian velocity, \Theta is the half-opening angle of the flow, and \gamma is the adiabatic index.Comment: 4 pages, 2 figures, accepted by Science in China Series

Two dimensional numerical simulations of Supercritical Accretion Flows revisited

We study the dynamics of super-Eddington accretion flows by performing two-dimensional radiation-hydrodynamic simulations. Compared with previous works, in this paper we include the $T_{\theta\phi}$ component of the viscous stress and consider various values of the viscous parameter $\alpha$. We find that when $T_{\theta\phi}$ is included, the rotational speed of the high-latitude flow decreases, while the density increases and decreases at the high and low latitudes, respectively. We calculate the radial profiles of inflow and outflow rates. We find that the inflow rate decreases inward, following a power law form of $\dot{M}_{\rm in}\propto r^s$. The value of $s$ depends on the magnitude of $\alpha$ and is within the range of $\sim 0.4-1.0$. Correspondingly, the radial profile of density becomes flatter compared with the case of a constant $\dot{M}(r)$. We find that the density profile can be described by $\rho(r)\propto r^{-p}$, and the value of $p$ is almost same for a wide range of $\alpha$ ranging from $\alpha=0.1$ to $0.005$. The inward decrease of inflow accretion rate is very similar to hot accretion flows, which is attributed to the mass loss in outflows. To study the origin of outflow, we analyze the convective stability of slim disk. We find that depending on the value of $\alpha$, the flow is marginally stable (when $\alpha$ is small) or unstable (when $\alpha$ is large). This is different from the case of hydrodynamical hot accretion flow where radiation is dynamically unimportant and the flow is always convectively unstable. We speculate that the reason for the difference is because radiation can stabilize convection. The origin of outflow is thus likely because of the joint function of convection and radiation, but further investigation is required.Comment: 16 pages, 13 figures, accepted for publication in Ap

Vertical Structure of Neutrino-Dominated Accretion Disk and Applications to Gamma-Ray Bursts

We revisit the vertical structure of neutrino-dominated accretion flows in spherical coordinates. We stress that the flow should be geometrically thick when advection becomes dominant. In our calculation, the luminosity of neutrino annihilation is enhanced by one or two orders of magnitude. The empty funnel along the rotation axis can naturally explain the neutrino annihilable ejection.Comment: 13 pages, 3 figures, accepted for publication in Ap

Che

Che (1967) is dedicated to the memory of Major Ernesto Guevara. This slim issue tackles A View from Harlem, Peace and Power, Detroit Cops: Brutal or Stupid, Reflections On A Riot, A Modest Proposal Revisited, Build Up to a Revolution, and Cuba; Fidelistas Vs. Communists. This publication is a booklet featuring articles mainly concerned with the politics of the time. The booklet is filled with simple type-writer typed pages and an orange cover paper cover with the title Che drawn on. The articles included cover topics ranging from the death of Che Guevara, race in Harlem, the Black Power movement, police brutality, the Vietnam War, and Cuba. Together, the articles paint a very interesting view of a portion of American politics and social issues in the late 1960s presented by Wooster students. This publication covers sensitive topics.https://openworks.wooster.edu/alternative_voices/1002/thumbnail.jp