Showing papers by "Roger H. Hildebrand published in 1982"
TL;DR: In this article, the 400 micron emission from the central region of OMC-1 has been mapped with 35 resolution, and two emission peaks with sizes of about 0.5 arcmin are found about 15 arcsec SE of the ionization front near Theta 2 A Ori, indicating a sharp increase in dust density in neutral matter outside the ionized region.
Abstract: The 400 micron emission from the central region of OMC-1 has been mapped with 35 resolution. This region contains two emission peaks with sizes of about 0.5 arcmin, separated by approximately 1.5 arcmin which probably represent distinct density condensations in the molecular cloud. Comparison of observations with earlier far-infrared observations shows the two condensations to have similar optical depths and dust masses. A bar of 400 micron emission is found about 15 arcsec SE of the ionization front near Theta 2 A Ori, indicating a sharp increase in dust density in the neutral matter outside the ionized region.
60 citations
TL;DR: In this paper, high-speed two-color photometric observations have been made of the dwarf nova EM Cyg and rapid coherent oscillations with periods between 14.6 and 16.5 sec have been found.
Abstract: High-speed two-color photometric observations have been made of the dwarf nova EM Cyg and rapid coherent oscillations with periods between 14.6 and 16.5 sec have been found. The minimum period is less than the period of a Keplerian orbit at the surface of a carbon white dwarf. The color temperature of the oscillating component is much higher than that of the constant component of the luminosity. These results suggest that the source of the oscillations is the white dwarf or the inner part of the accretion disk.
5 citations
Journal Article•
TL;DR: A 35 arcsec resolution, 400 micron continuum map of the core of the W3 molecular cloud complex is presented in this paper, showing prominent peaks centered approximately at the positions of the infrared sources IRS 4 and IRS 5 with stronger-emission at the western (IRS 4) peak.
Abstract: A 35 arcsec resolution, 400 micron continuum map of the core of the W3 molecular cloud complex is presented. The map shows prominent peaks centered approximately at the positions of the infrared sources IRS 4 and IRS 5 with stronger-emission at the western (IRS 4) peak. The visual extinction (inferred from the submillimeter measurements) through the center of both peaks is large (A sub v = 200). A total mass for the core of 900 solar masses is estimated, consistent with dynamical estimates if the observed velocity gradient is a result of rotation. The peak H2 density is approximately 2.8 x 10 to the 5th/cu cm. The observations exclude the possibility that the shell H II regions, W3A-C, could be in pressure equilibrium with the surrounding cloud. The observations establish that the core of W3 contains several massive condensations surrounding the youngest stars in the region.