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A cornerstone of Einstein's special relativity is Lorentz invariance-the postulate that all observers measure exactly the same speed of light in vacuum, independent of photon-energy. While special relativity assumes that there is no fundamental length-scale associated with such invariance, there is a fundamental scale (the Planck scale, l(Planck)(More)
Pulsars are born with subsecond spin periods and slow by electromagnetic braking for several tens of millions of years, when detectable radiation ceases. A second life can occur for neutron stars in binary systems. They can acquire mass and angular momentum from their companions, to be spun up to millisecond periods and begin radiating again. We searched(More)
User-level threads have been used to implement migratable MPI processes. This is a better strategy to implement load balancing mechanisms. That is because, in general, these threads are faster to create, manage and migrate than heavy processes and kernel threads. However, they present some issues concerning private data because they break the private(More)
Gamma-ray bursts (GRBs) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Gamma-ray Burst Monitor and Large Area Telescope onboard the Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades of gammaray energy. In September 2008, Fermi observed the exceptionally luminous GRB(More)
We revisit and use the dependence transformation method to generate parallel algorithms suitable for cluster and grid computing. We illustrate this method in two applications: to obtain a systolic matrix product algorithm, and to compute the alignment score of two strings. The product of two n × n matrices is viewed as multiplying two p × p matrices whose(More)
Energetic young pulsars and expanding blast waves [supernova remnants (SNRs)] are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a radio quiet pulsar located near the center of the compact synchrotron nebula inside the supernova remnant CTA 1. The(More)
We report the detection of high energy γ-ray emission from the young and energetic pul-sar PSR B1509−58 and its pulsar wind nebula (PWN) in the composite supernova remnant SNR G320.4−1.2 (aka MSH 15−52). Using 1 year of survey data with the Fermi-Large Area Telescope (LAT), we detected pulsations from PSR B1509−58 up to 1 GeV and extended γ-ray emission(More)
We report the detection of pulsed gamma-rays from the young, spin-powered radio pulsar PSR J2021+3651 using data acquired with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST). The light curve consists of two narrow peaks of similar amplitude separated by 0.468 ± 0.002 in phase. The first peak lags the maximum of the 2(More)
We report the detection of gamma-ray emissions above 200 megaelectron volts at a significance level of 17sigma from the globular cluster 47 Tucanae, using data obtained with the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. Globular clusters are expected to emit gamma rays because of the large populations of millisecond pulsars that they(More)
We present a measurement of the time-dependent CP-violating (CPV) asymmetries in B0-->K(0)(S)pi(0) decays based on 124x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. In a sample containing 122+/-16 signal decays, we obtain the magnitudes of the direct CPV asymmetry(More)