5,439 research outputs found
The Interplanetary Network Supplement to the BeppoSAX Gamma-Ray Burst Catalogs
Between 1996 July and 2002 April, one or more spacecraft of the
interplanetary network detected 787 cosmic gamma-ray bursts that were also
detected by the Gamma-Ray Burst Monitor and/or Wide-Field X-Ray Camera
experiments aboard the BeppoSAX spacecraft. During this period, the network
consisted of up to six spacecraft, and using triangulation, the localizations
of 475 bursts were obtained. We present the localization data for these events.Comment: 89 pages, 3 figures. Submitted to the Astrophysical Journal
Supplement Serie
An Analysis of the Tradeoffs between Policy Instruments to Induce Dairy Producers in California to Participate in a Centralized Digester
Tradeoff between different utility rates and policy intervention to induce dairy producer to join a regional digester are studied. Results demonstrate that a regional digester for the dairy industry in California is feasible given the digester receives 0.0925 per kWh with no intervention.Agricultural and Food Policy, Livestock Production/Industries,
A Note on Probability Trees
Not many introductory probability and statistics textbooks emphasize the use of probability trees to make complex probability calculations. This is puzzling in view of the power that trees bring to organizing such calculations for students. An effective classroom technique is discussed is this note
A Note On MLEs For Normal Distribution Parameters Based On Disjoint Partial Sums Of A Random Sample
Maximum likelihood estimators are computed for the parameters of a normal distribution based on disjoint partial sums of a random sample. It has application in the disaggregation of financial data
On the Length of NHL Shootouts
When NHL teams are tied after 60 minutes of regulation time and 5 minutes of sudden-death overtime, they go to a shootout to determine who gets the overtime point. Teams alternate shots until a winner is determined. The probability of observing shootouts of various lengths is calculated
Nature of fault planes in solid neutron star matter
The properties of tectonic earthquake sources are compared with those deduced
here for fault planes in solid neutron-star matter. The conclusion that
neutron-star matter cannot exhibit brittle fracture at any temperature or
magnetic field is significant for current theories of pulsar glitches, and of
the anomalous X-ray pulsars and soft-gamma repeaters.Comment: 5 AAS LaTeX pages 1 eps figur
TeV Burst of Gamma-Ray Bursts and Ultra High Energy Cosmic Rays
Some recent experiments detecting very high energy (VHE) gamma-rays above
10-20 TeV independently reported VHE bursts for some of bright gamma-ray bursts
(GRBs). If these signals are truly from GRBs, these GRBs must emit a much
larger amount of energy as VHE gamma-rays than in the ordinary photon energy
range of GRBs (keV-MeV). We show that such extreme phenomena can be reasonably
explained by synchrotron radiation of protons accelerated to \sim 10^{20-21}
eV, which has been predicted by Totani (1998a). Protons seem to carry about
(m_p/m_e) times larger energy than electrons, and hence the total energy
liberated by one GRB becomes as large as \sim 10^{56} (\Delta \Omega / 4 \pi)
ergs. Therefore a strong beaming of GRB emission is highly likely. Extension of
the VHE spectrum beyond 20 TeV gives a nearly model-independent lower limit of
the Lorentz factor of GRBs, as \gamma \gtilde 500. Furthermore, our model
gives the correct energy range and time variability of ordinary keV-MeV
gamma-rays of GRBs by synchrotron radiation of electrons. Therefore the VHE
bursts of GRBs strongly support the hypothesis that ultra high energy cosmic
rays observed on the Earth are produced by GRBs.Comment: Final version to appear in ApJ Lett. Emphasizing that the extremely
large energy required in this model is not theoretically impossible if GRB
emission is strongly beamed. References update
Detailed transonic flow field measurements about a supercritical airfoil section
The transonic flow field about a Whitcomb-type supercritical airfoil profile was measured in detail. In addition to the usual surface pressure distributions and wake surveys, schlieren photographs were taken and velocity vector profiles were determined in the upper surface boundary layer and in the near wake. Spanwise variations in the measured pressures were also determined. The data are analyzed with the aid of an inviscid transonic finite-difference computer program as well as with boundary layer modeling and calculation schemes
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