Zobrazeno 1 - 10
of 45
pro vyhledávání: '"Hester, J. J."'
Publikováno v:
Astrophys.J.662:1268-1281,2007
The early Solar System contained short-lived radionuclides such as 60Fe (t1/2 = 1.5 Myr) whose most likely source was a nearby supernova. Previous models of Solar System formation considered a supernova shock that triggered the collapse of the Sun's
Externí odkaz:
http://arxiv.org/abs/0704.1652
During the last three decades, evidence has mounted that star and planet formation is not an isolated process, but is influenced by current and previous generations of stars. Although cool stars form in a range of environments, from isolated globules
Externí odkaz:
http://arxiv.org/abs/0704.1045
Autor:
Blagrave, K. P. M., Martin, P. G., Rubin, R. H., Dufour, R. J., Baldwin, J. A., Hester, J. J., Walter, D. K.
Publikováno v:
Astrophys.J.655:299-315,2007
We are engaged in a comprehensive program to find reliable elemental abundances in and to probe the physical structure of the Orion Nebula, the brightest and best-resolved H II region. In the course of developing a robust extinction correction coveri
Externí odkaz:
http://arxiv.org/abs/astro-ph/0610621
Publikováno v:
Astrophys.J. 615 (2004) 794-804
We present four new, high-resolution VLA radio images of the Crab nebula, taken between 2001 Feb. and Apr. The radio images show systematic variability in the Crab's radio emission throughout the region near the pulsar. The principal geometry of the
Externí odkaz:
http://arxiv.org/abs/astro-ph/0408061
Autor:
Moon, D. -S., Lee, J. -J., Eikenberry, S. S., Koo, B. -C., Chatterjee, S., Kaplan, D. L., Hester, J. J., Cordes, J. M., Gallant, Y. A., Koch-Miramond, L.
Publikováno v:
Astrophys.J. 610 (2004) L33-L36
The radio pulsar B1951+32 and the supernova remnant CTB 80 provide a rich laboratory for the study of neutron stars and supernova remnants. Here, we present ground-based optical and near-infrared observations of them, along with X-ray observations wi
Externí odkaz:
http://arxiv.org/abs/astro-ph/0406240
Publikováno v:
Astrophys.J. 609 (2004) 186-193
We present spectral analysis of the Crab Nebula obtained with the {\it Chandra} X-ray observatory. The X-ray spectrum is characterized by a power-law whose index varies across the nebula. The variation can be discussed in terms of the particle inject
Externí odkaz:
http://arxiv.org/abs/astro-ph/0403287
We present year-scale morphological variations of the Crab Nebula revealed by Chandra X-ray observatory. Observations have been performed about every 1.7 years over the 3 years from its launch. The variations are clearly recognized at two sites: the
Externí odkaz:
http://arxiv.org/abs/astro-ph/0311409
We present a series of monitoring observations of the Crab Nebula with the Chandra X-ray Observatory, focusing on the temporal evolution of the structure. This series of 8 observations, spanning a period of approximately six months, shows the dynamic
Externí odkaz:
http://arxiv.org/abs/astro-ph/0112250
We present three high resolution radio images of the Crab nebula, taken in 1998.6, 1998.8 and 2000.1 with the VLA. These are the best radio images of the Crab to date. We show that, near the pulsar, there are significant changes between our three obs
Externí odkaz:
http://arxiv.org/abs/astro-ph/0106339
Using the Hubble Space Telescope and WFPC2 we have imaged the central 20pc of the giant H II region 30 Doradus nebula in three different emission lines. The images allow us to study the nebula with a physical resolution that is within a factor of two
Externí odkaz:
http://arxiv.org/abs/astro-ph/9803301