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Discovery of an Eclipsing X-Ray Binary with a 32.69 hr Period in M101: An Analog of Her X-1 or LMC X-4?
DOI: 10.1086/508447 Bibcode: 2006ApJ...653..602L

Liu, Jifeng; Di Stefano, Rosanne; Kuntz, Kip +3 more

We report the discovery of an eclipsing X-ray binary in M101, the first such system to be discovered outside the Local Group. Based on a sequence of 25 Chandra observations that sample a wide range of orbital phases, we find a period of 32.688+/-0.002 hr, which we interpret as an orbital period. The folded light curve exhibits an eclipse lasting a…

2006 The Astrophysical Journal
eHST 4
Time-Distance Measurements of Cross-Correlation Asymmetries around NOAA AR 10486
DOI: 10.1086/507517 Bibcode: 2006ApJ...648L..75J

Thompson, Michael J.; Jensen, Jesper M.; Pijpers, Frank P.

We apply time-distance helioseismology to NOAA AR 10486 in order to examine the effect the presence of magnetic fields has on the resulting cross-correlations. Large-amplitude asymmetries between waves propagating in opposite directions are observed. The asymmetries can be attributed to suppression and absorption of seismic waves by the magnetic f…

2006 The Astrophysical Journal
SOHO 4
Radio and Hard X-Ray Imaging Observations of the M5.7 Flare of 2002 March 14
DOI: 10.1086/503151 Bibcode: 2006ApJ...643.1271S

Kundu, M. R.; Garaimov, V. I.; Schmahl, E. J.

We describe a flare of GOES class M5.7 that was observed simultaneously by RHESSI (Ramaty High Energy Solar Spectroscopic Imager) and NoRH (Nobeyama Radio Heliograph). The flare occurred in AR 9866 located near the disk center. The hard X-ray (HXR), microwave, EIT, and TRACE 195 Å observations indicate that the flaring region consisted of a comple…

2006 The Astrophysical Journal
SOHO 4
Modeling the Evolution of Dusty Starburst Galaxies in Multiband Deep Surveys
DOI: 10.1086/498696 Bibcode: 2006ApJ...638..138W

Wang, Y. P.

We model the constraints set on the evolution of dusty starburst galaxies by the current deep extragalactic surveys performed in the far-infrared with Spitzer, and at radio wavelengths with the VLA. Our models fit the number counts in all the available spectral bands well and also provide a reasonably close match to the redshift distribution of th…

2006 The Astrophysical Journal
ISO 3
Great Storm Particle Event on 2000 August 11 Observed by SOHO ERNE
DOI: 10.1086/498670 Bibcode: 2006ApJ...638..530T

Riihonen, E.; Torsti, J.; Mäkelä, P. +1 more

We report on an energetic storm particle event on 2000 August 11 observed by ERNE on board SOHO. A large-intensity enhancement started simultaneously in all energy channels between 2 and 50 MeV at 11 UT. The concurrence of the onsets indicates the local nature of the particle event. Intensities increased 100-fold from the background level before 1…

2006 The Astrophysical Journal
SOHO 3
The Bright Ages Survey. I. Imaging Data
DOI: 10.1086/499095 Bibcode: 2006ApJ...638..603C

Salim, Samir; Rich, R. Michael; Frogel, Jay A. +3 more

This is the first paper in a series presenting and analyzing data for a K-selected sample of galaxies collected in order to identify and study galaxies at moderate to high redshift in rest-wavelength optical light. The sample contains 842 objects over six separate fields covering 75.6 arcmin2 down to K=20-20.5. We combine the K band wit…

2006 The Astrophysical Journal
eHST 2
Passively Evolving Early-Type Galaxies at 1.4 <~ z <~ 2.5 in the Hubble Ultra Deep Field
DOI: 10.1086/430104 Bibcode: 2005ApJ...626..680D

Cimatti, A.; Daddi, E.; Panagia, N. +13 more

We report on a complete sample of seven luminous early-type galaxies in the Hubble Ultra Deep Field (UDF) with spectroscopic redshifts between 1.39 and 2.47, and to KAB<23. Using the BzK selection criterion, we have preselected a set of objects over the UDF, which fulfill the photometric conditions for being passively evolving galaxi…

2005 The Astrophysical Journal
eHST 813
Confined and Ejective Eruptions of Kink-unstable Flux Ropes
DOI: 10.1086/462412 Bibcode: 2005ApJ...630L..97T

Török, T.; Kliem, B.

The ideal helical kink instability of a force-free coronal magnetic flux rope, anchored in the photosphere, is studied as a model for solar eruptions. Using the flux rope model of Titov and Démoulin as the initial condition in MHD simulations, both the development of helical shape and the rise profile of a confined (or failed) filament eruption (o…

2005 The Astrophysical Journal
SOHO 787
The Relationship between Luminosity and Broad-Line Region Size in Active Galactic Nuclei
DOI: 10.1086/431275 Bibcode: 2005ApJ...629...61K

Kaspi, Shai; Peterson, Bradley M.; Maoz, Dan +3 more

We reinvestigate the relationship between the characteristic broad-line region size (RBLR) and the Balmer emission-line, X-ray, UV, and optical continuum luminosities. Our study makes use of the best available determinations of RBLR for a large number of active galactic nuclei (AGNs) from Peterson et al. Using their determina…

2005 The Astrophysical Journal
IUE eHST 756
Evolution of the Solar Activity over Time and Effects on Planetary Atmospheres. I. High-Energy Irradiances (1-1700 Å)
DOI: 10.1086/427977 Bibcode: 2005ApJ...622..680R

Güdel, Manuel; Guinan, Edward F.; Audard, Marc +1 more

We report on the results of the Sun in Time multiwavelength program (X-rays to UV) of solar analogs with ages covering ~0.1-7 Gyr. The chief science goals are to study the solar magnetic dynamo and to determine the radiative and magnetic properties of the Sun during its evolution across the main sequence. The present paper focuses on the latter go…

2005 The Astrophysical Journal
IUE eHST 688