Search Publications
Observation of solar energetic particle (SEP) events associated with narrow CMEs
Valtonen, E.; Al-Sawad, A.; Allawi, H. +1 more
We report here on two proton energetic particle events observed by the Energetic and Relativistic Nuclei and Electron (ERNE) instrument on the Solar and Heliospherical Observatory (SOHO). Both events were impulsive (SEP) events with intensities of >10-3 cm-2 sr-1 s-1 MeV-1 at an energy rang…
Angular Clustering of Fir-Selected Galaxies in the Akari All-Sky Survey
Oyabu, S.; Takeuchi, T. T.; Pollo, A. +1 more
We present the first measurement of the angular two-point correlation function for AKARI 90-$\mu$m point sources, detected outside of the Milky Way plane and other regions characterized by high Galactic extinction, and categorized as extragalactic sources according to our far-infrared-color based criterion (Pollo et al. 2010). This is the first me…
On the spatial character of the ∼10 h electron spectrum modulation in the Jovian magnetosphere
Anagnostopoulos, G. C.; Karanikola, I.
On its voyage in the south duskside Jovian magnetosphere, after leaving the plasma sheet, Ulysses entered a large scale high latitude layer of energetic ions and electrons, extending from ∼49 RJ to ∼83 RJ. Ulysses traveled within this region from the end of day 41 until the first magnetopause crossing, early on day 43, 1992 a…
Observations of a broad and dynamic region of radiation in geospace
Chen, Jiasheng; Lyu, Ling-Hsiao
The solar wind particles can directly access the high-altitude cusp. They could create large diamagnetic cavities with a size of 6RE (Earth radii) in the latitudinal direction and >10RE in the longitudinal direction at an altitude of 7-8RE, and up to 10.5RE in the depth; they could depress the field f…
Dayside and nightside segments of a polar arc: The particle characteristics
Parks, G. K.; Zhang, Y.; Lee, J. -J. +8 more
Using multiple satellites and a ground-based radar network, the physical characteristics of a polar arc and its evolution are investigated under quiet solar wind conditions. The average electron energy is higher at the near-midnight segment than at the sunward extension of the polar arc. Both polar arc segments are positioned primarily on closed m…
Archival HST study of novae. I. The Seyfert galaxy NGC 3627
Alis, S.; Saygaç, A. T.
A V-band nova search was carried out in NGC 3627 with archival Hubble Space Telescope WFPC2 data which was obtained in the period between November 1997 and January 1998. A total of four novae candidates were discovered which corresponds to a global nova rate of R = 83.65 ± 7.58 yr -1. Taking into account the K-band luminosity obtained f…
The History of Variable Stars: A Fresh Look
Hatch, R. A.
(Abstract only) For historians of astronomy, variable stars are important for a simple reason - stars change. But good evidence suggests this is a very modern idea. Over the millennia, our species has viewed stars as eternal and unchanging, forever fixed in time and space - indeed, the Celestial Dance was a celebration of order, reason, and stabil…
Foreground Predictions for the Cosmic Microwave Background Power Spectrum from Measurements of Faint Inverted Radio Sources at 5 GHz
White, Richard L.; Becker, Robert H.; Schneider, Michael D. +1 more
We present measurements of a population of matched radio sources at 1.4 and 5 GHz down to a flux limit of 1.5 mJy in 7 deg2 of the NOAO Deep Field South. We find a significant fraction of sources with inverted spectral indices that all have 1.4 GHz fluxes less than 10 mJy and are therefore too faint to have been detected and included in…
Systematic Bundle Adjustment of HRSC Image Data
Schmidt, R.; Bostelmann, J.; Heipke, C.
The European Mars Express mission was launched in June 2003 and sent into orbit around Mars. On board the orbiter is the German High Resolution Stereo Camera (HRSC). This multi-line sensor images the Martian surface with a resolution of up to 12m per pixel in three dimensions and provides RGB and infra-red color information. The usage of the stere…
Plasma particle simulations on stray photoelectron current flows around a spacecraft
Miyake, Y.; Usui, H.; Nakashima, H. +1 more
In tenuous space plasmas, photoelectron flows produce complex current paths among multiple conducting elements of spacecraft, which may influence the current-voltage characteristics of double-probe electric field sensors. We performed full-particle simulations on this effect by assuming a sensor configuration that is typical of recent designs like…