10,425 research outputs found
Wigner's -matrix elements for - A Generating Function Approach
A generating function for the Wigner's -matrix elements of is
derived. From this an explicit expression for the individual matrix elements is
obtained in a closed form.Comment: RevTex 3.0, 22 pages, no figure
Coping Ability of Medical and Nursing Students: A Cause of Concern
Background: Medical students today are subject to a variety of stress; academic, social, emotional or stress in the form of affliction of health during their stay at medical school. The physiological response to these depends on various factors including their inherent coping abilities. This study was designed to examine the coping ability of medical and nursing students at the time of admission to medical school. Materials and Methods: 42 medical and 34 nursing students volunteered for the study. They were administered the BAI questionnaire and classified as good and poor adjusters based on their score. Results: The study revealed an unsatisfactory overall coping ability to be prevalent among medical and nursing students. Conclusion: This study showed that there is a need for orientation and counselling of medical and nursing students at the start of college
Evolution of Proto-Neutron stars with kaon condensates
We present simulations of the evolution of a proto-neutron star in which
kaon-condensed matter might exist, including the effects of finite temperature
and trapped neutrinos. The phase transition from pure nucleonic matter to the
kaon condensate phase is described using Gibbs' rules for phase equilibrium,
which permit the existence of a mixed phase. A general property of neutron
stars containing kaon condensates, as well as other forms of strangeness, is
that the maximum mass for cold, neutrino-free matter can be less than the
maximum mass for matter containing trapped neutrinos or which has a finite
entropy. A proto-neutron star formed with a baryon mass exceeding that of the
maximum mass of cold, neutrino-free matter is therefore metastable, that is, it
will collapse to a black hole at some time during the Kelvin-Helmholtz cooling
stage.
The effects of kaon condensation on metastable stars are dramatic. In these
cases, the neutrino signal from a hypothetical galactic supernova (distance
kpc) will stop suddenly, generally at a level above the background in
the SuperK and SNO detectors, which have low energy thresholds and backgrounds.
This is in contrast to the case of a stable star, for which the signal
exponentially decays, eventually disappearing into the background. We find the
lifetimes of kaon-condensed metastable stars to be restricted to the range
40--70 s and weakly dependent on the proto-neutron star mass, in sharp contrast
to the significantly larger mass dependence and range (1--100 s) of
hyperon-rich metastable stars.Comment: 25 pages, 14 figures. Submitted to Astrophysical Journa
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