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A Markov Stochastic Process Theory of Cosmic-Ray Modulation
Zhang, Ming
This paper introduces the use of Markov stochastic process theory to study heliospheric modulation of cosmic rays. The basic cosmic-ray transport equation is reformulated with a set of stochastic differential equations that describe the guiding center and momentum of individual charged particles randomly walking in the heliospheric magnetic field.…
Dust in the Local Interstellar Wind
Zank, Gary P.; Slavin, Jonathan D.; Geiss, Johannes +13 more
The gas-to-dust mass ratios found for interstellar dust within the solar system, versus values determined astronomically for the cloud around the solar system, suggest that large and small interstellar grains have separate histories and that large interstellar grains preferentially detected by spacecraft are not formed exclusively by mass exchange…
Reactivation and Precise Interplanetary Network Localization of the Soft Gamma Repeater SGR 1900+14
Cline, T.; Hurley, K.; Kouveliotou, C. +5 more
In 1998 May, the soft gamma repeater SGR 1900+14 emerged from several years of quiescence and emitted a series of intense bursts, one with a time history unlike any previously observed from this source. Triangulation using Ulysses, BATSE, and KONUS data gives a 1.6 arcmin2 error box near the Galactic supernova remnant G42.8+0.6. This er…
Gravitationally Lensed Gamma-Ray Bursts as Probes of Dark Compact Objects
Hurley, K.; Norris, J. P.; Marani, G. F. +2 more
If dark matter in the form of compact objects comprises a large fraction of the mass of the universe, then gravitational lensing effects on gamma-ray bursts are expected. We utilize BATSE and Ulysses data to search for lenses of different mass ranges, which cause lensing in the milli, pico, and femto regimes. Null results are used to set weak limi…
Precise Interplanetary Network Localization of a New Soft Gamma Repeater, SGR 1627-41
Cline, T.; Hurley, K.; Kouveliotou, C. +5 more
We present Ulysses, Konus-Wind, and BATSE observations of bursts from a new soft gamma repeater that was active in 1998 June and July. Triangulation of the bursts results in a ~1.8d by 16" error box whose area is ~7.6 arcmin2 and which contains the Galactic supernova remnant G337.0-0.1. This error box intersects the position of a BeppoS…
Imprint of the Sun on the Solar Wind
Habbal, Shadia Rifai; Woo, Richard
Observations of the inner corona in polarized brightness by the Mauna Loa Mk III K-coronameter at 1.15 Rsolar and soft X-rays by Yohkoh at 1.03 Rsolar are combined with 1995 Ulysses radio occultation measurements of the solar wind to demonstrate that the signatures of the coronal hole boundary, active regions, and bright poin…
A Path Integral Approach to the Theory of Heliospheric Cosmic-Ray Modulation
Zhang, Ming
This paper introduces the path integral method, which has been widely used in quantum mechanics and statistical mechanics, into the field of cosmic-ray modulation theory to solve the Fokker-Planck equation for cosmic-ray transport. The path integral approach recognizes that the motion of cosmic rays is a Markov stochastic process. The derivation o…
The Search for Solar Gravity-Mode Oscillations: an Analysis Using ULYSSES Magnetic Field Data
Denison, David G. T.; Walden, Andrew T.
In 1995 Thomson, Maclennon, and Lanzerotti (TML) reported on work where they carried out a time-series analysis of energetic particle fluxes measured by Ulysses and Voyager 2 and concluded that solar g-mode oscillations had been detected. The approach is based on finding significant peaks in spectra using a statistical F-test. Using three sets of …