5,177 research outputs found
Catalogue of solar activity during 1957
Catalog of major solar activity during 195
Solar activity catalogue. Volume I - Catalogue of solar activity during 1954 - 1956
Catalog of solar activity during 1954-195
Catalogue of Solar Activity During 1958, Volume III
Solar flares, sunspots, radio emissions, solar events, geomagnetic storms, solar-terrestrial effects, and balloon flights for 195
Solar activity catalogue. Volume 4 - Catalogue of solar activity during 1959
Solar activity catalog covering solar flares, terrestrial effects, plage regions, radio emissions, geomagnetic storms, and balloon flight
Expected characteristics of the subclass of Supernova Gamma-ray Bursts (S-GRBs)
The spatial and temporal coincidence between the gamma-ray burst (GRB) 980425
and supernova (SN) 1998bw has prompted speculation that there exists a class of
GRBs produced by SNe (``S-GRBs''). Robust arguments for the existence of a
relativistic shock have been presented on the basis of radio observations. A
physical model based on the radio observations lead us to propose the following
characteristics of supernovae GRBs (S-GRBs): 1) prompt radio emission and
implied brightness temperature near or below the inverse Compton limit, 2) high
expansion velocity of the optical photosphere as derived from lines widths and
energy release larger than usual, 3) no long-lived X-ray afterglow, and 4) a
single pulse (SP) GRB profile. Radio studies of previous SNe show that only
type Ib and Ic potentially satisfy the first condition. Accordingly we have
investigated proposed associations of GRBs and SNe finding no convincing
evidence (mainly to paucity of data) to confirm any single connection of a SN
with a GRB. If there is a more constraining physical basis for the burst
time-history of S-GRBs beyond that of the SP requirement, we suggest the 1% of
light curves in the BATSE catalogue similar to that of GRB 980425 may
constitute the subclass. Future optical follow-up of bursts with similar
profiles should confirm if such GRBs originate from some fraction of SN type
Ib/Ic.Comment: 11 pages of LaTeX with 1 figure. Submitted to the Astrophysical
Journal Letter
A Group Theoretical Identification of Integrable Equations in the Li\'enard Type Equation : Part II: Equations having Maximal Lie Point Symmetries
In this second of the set of two papers on Lie symmetry analysis of a class
of Li\'enard type equation of the form ,
where over dot denotes differentiation with respect to time and and
are smooth functions of their variables, we isolate the equations which
possess maximal Lie point symmetries. It is well known that any second order
nonlinear ordinary differential equation which admits eight parameter Lie point
symmetries is linearizable to free particle equation through point
transformation. As a consequence all the identified equations turn out to be
linearizable. We also show that one can get maximal Lie point symmetries for
the above Li\'enard equation only when (subscript denotes
differentiation). In addition, we discuss the linearising transformations and
solutions for all the nonlinear equations identified in this paper.Comment: Accepted for publication in Journal of Mathematical Physic
Catalogue of Solar Activity During 1960-1963, Volume V
Catalog on solar activity from 1960 to 196
Bumpy Black Holes in Alternate Theories of Gravity
We generalize the bumpy black hole framework to allow for alternative theory
deformations. We construct two model-independent parametric deviations from the
Kerr metric: one built from a generalization of the quasi-Kerr and bumpy
metrics and one built directly from perturbations of the Kerr spacetime in
Lewis-Papapetrou form. We find the conditions that these "bumps" must satisfy
for there to exist an approximate second-order Killing tensor so that the
perturbed spacetime still possesses three constants of the motion (a deformed
energy, angular momentum and Carter constant) and the geodesic equations can be
written in first-order form. We map these parameterized metrics to each other
via a diffeomorphism and to known analytical black hole solutions in
alternative theories of gravity. The parameterized metrics presented here serve
as frameworks for the systematic calculation of extreme-mass ratio inspiral
waveforms in parameterized non-GR theories and the investigation of the
accuracy to which space-borne gravitational wave detectors can constrain such
deviations.Comment: 17 pages, replaced with version published in Phys. Rev.
Lessons from the Field: A Systems Thinking Approach for Case Management Documentation
Case management is a core HIV health service that focuses on service coordination—the seamless access to an array of integrated services. Integration aims to reduce barriers to medical care. In the busy HIV health services environment, inadequate documentation of case management activities limits the capacity of stakeholders to know what happens during care encounters. This study used theory and qualitative inquiry to uncover best practices that support optimal case management documentation. Two research questions guided the inquiry: What principles should arise in higher order cognitive functioning among case managers during client encounters? What characteristics of a system level approach to care encounter documentation reinforces case management critical thinking skills? The study settings included two, Northeast Florida, Ryan White funded organizations. Findings indicated that the confluence of intrapersonal, interpersonal, organizational, community, and policy factors support more rather than less robust case management documentation. A multi-tired approach to documentation of services rendered is no panacea. However, it offers a useful framework for defining stakeholders’ roles and expectations and monitoring the performance of activities. Disseminating these findings in the local Ryan White network and the public domain may trigger dialog and more research about the preservation and effective use of documentation skills
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