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Barnard's Star and the M Dwarf Temperature Scale
De Robertis, M. M.; Dawson, P. C.
The recently measured angular diameter of Barnard's star, together with its large and precise parallax, and a spectral energy distribution that extends from the near-ultraviolet to almost 12 µm establish some of the star's fundamental properties-we find a bolometric luminosity L=(3.46+/-0.17)×10-3Lsolar, radius R=0.200+…
86 GHz SiO maser survey of late-type stars in the inner Galaxy. II. Infrared photometry of the SiO target stars
Menten, K. M.; Omont, A.; Habing, H. J. +2 more
We present a compilation and study of DENIS, 2MASS, ISOGAL, MSX and IRAS 1-25 µm photometry for a sample of 441 late-type stars in the inner Galaxy, which we previously searched for 86 GHz SiO maser emission \citep{messineo02}. The comparison of the DENIS and 2MASS J and KS magnitudes shows that most of the SiO targets are indeed …
October-November 2003's space weather and operations lessons learned
Barbieri, L. P.; Mahmot, R. E.
The Sun-Earth space weather related to sunspots NOAA 484, 486, and 488 affected a number of NASA spacecraft and instruments between mid-October and early November 2003. Information available from Earth and space science missions indicate that about 59% of the spacecraft and about 18% of the instrument groups experienced some effect from the solar …
The configuration of simple short-duration solar microwave bursts
Nindos, A.; Kundu, M. R.; Grechnev, V. V.
Using data from the Nobeyama Radioheliograph (NoRH) we study the source configuration of four simple short-duration 17 and 34 GHz bursts which have also been observed partially by the Yohkoh Soft X-ray Telescope (SXT). Two events are consistent with a single flaring loop configuration. In one of them the flaring loop is resolved in the SXT images.…
The X-ray, optical and radio evolution of the GRB 030329 afterglow and the associated SN2003dh
O'Brien, P. T.; Osborne, J. P.; Page, K. L. +3 more
Extensive X-ray, optical and radio observations of the bright afterglow of the gamma-ray burst GRB 030329 are used to construct the multifrequency evolution the event. The data are fitted using the standard fireball shock model to provide estimates of the initial energy, ɛ= 6.8 × 1052 erg sr-1, the density of the ambient medi…
On the Spatial Dependence of Low-Degree Solar p-Mode Frequency Shifts from Full-Disk and Resolved-Sun Observations
Korzennik, S. G.; Jiménez-Reyes, S. J.; García, R. A. +1 more
We have analyzed low angular degree (low-l) solar p-mode frequency shifts extracted from two types of observations, both made by instruments on board the ESA/NASA Solar and Heliospheric Observatory satellite during a period that covers the rising phase of activity, cycle 23 (1995-2002). The first are full-disk (Sun-as-a-star) averages made in Dopp…
Galactic Center Extinction: Evidence of Metallic Needles in the General Interstellar Medium
Dwek, Eli
The extinction curve derived from Infrared Space Observatory mid-infrared observations of the Galactic center (GC) exhibits a surprisingly flat behavior in the ~3-8 µm region, contrary to the deep minimum expected from standard interstellar dust models consisting of bare silicate and graphite dust particles. We show that this extinction is l…
A variable ultra-luminous X-ray source in the colliding galaxy NGC 7714
Motch, C.; Soria, R.
We studied the colliding galaxy NGC 7714 with two XMM-Newton observations, six months apart. The galaxy contains two bright X-ray sources: we show that they have different physical nature. The off-nuclear source is an accreting compact object, one of the brightest ultraluminous X-ray sources (ULXs) found to date. It showed spectral and luminosity …
GRB 021211 as a Faint Analog of GRB 990123: Exploring the Similarities and Differences in the Optical Afterglows
Bloom, J. S.; Caldwell, Nelson; Garnavich, Peter M. +7 more
We present BVRCJHKs photometry of the optical afterglow of the gamma-ray burst GRB 021211 taken at the Magellan, MMT, and WIYN observatories between 0.7 and 50 days after the burst. We find an intrinsic spectral slope at optical and near-infrared wavelengths of 0.69+/-0.14 at 0.87 days. The optical decay during the first day …
The heliospheric hydrogen wall and astrospheres
Linsky, J. L.; Zank, G. P.; Wood, B. E. +2 more
Charge exchange processes in the outer heliosphere produce a population of hot hydrogen gas within the heliosphere, creating a "hydrogen wall" between the heliopause and bow shock. The heliospheric hydrogen wall scatters Lyα photons passing through it, producing a detectable absorption signature in observations of H I Lyα emission from nearby star…