1,800 research outputs found
The Radio Emission from the Ultra-Luminous Far-Infrared Galaxy NGC 6240
We present new radio observations of the ``prototypical'' ultra-luminous far-
infrared galaxy NGC~6240, obtained using the VLA at 20~cm in `B' configuration
and at 3.6~cm in `A' configuration. These data, along with those from four
previous VLA observations, are used to perform a comprehensive study of the
radio emission from NGC~6240. Approximately 70\% (~3 x 10 W~Hz)
of the total radio power at 20 cm originates from the nuclear region ( <~ 1.5
kpc), of which half is emitted by two unresolved (\alphaS_{\nu} \propto \nu^{-\alpha}). The
supernova rate required to power the diffuse component is consistent with that
predicted by the stellar evolution models of Rieke \etal (1985). If the radio
emission from the two compact cores is powered by supernova remnants, then
either the remnants overlap and form hot bubbles in the cores, or they are very
young ( <~ 100 yr). Nearly all of the other 30\% of the total radio power comes
from an ``arm-like'' region extending westward from the nuclear region. The
western arm emission has a steep spectrum (\alpha^{-14}$ erg/s/cm2 in the 2-10 keV band. No significant radio
emission is detected from or near the possible ultra-massive ``dark core''
hypothesized by Bland-Hawthorn, Wilson \& Tully (1991).Comment: 36 pages (text and tables) as an uuencoded compressed postscript file
(figures available upon request), accepted for the ApJ (20 Nov issue), STScI
preprint no. ?? -- May 199
NASA micromin computer Monthly progress letter, Jan. 1967
Microminiature circuit development for flight control computer
Adolescent Dating Violence Prevention and Intervention in a Community Setting: Perspectives of Young Adults and Professionals
Adolescent dating violence (ADV) is a significant community problem. In this study, we examine the perspectives of two groups (young adults who experienced ADV as teens and professionals who work with teens) on ADV prevention/intervention in a community context. We interviewed 88 young adults and 20 professionals. Our research team used Thorne’s (2008) interpretive description methods to determine participants’ perspectives on community views on ADV, community ADV prevention/intervention programs, and ideal ADV prevention/intervention strategies. Participants perceived most communities as being blind to ADV. They perceived prevention programs as unavailable, inappropriate, or impersonal. Young adults indicated that professionals should use a gradual approach with teens experiencing ADV. Participants suggested that ideal prevention programs should include personal development and education. Helping professionals can use these findings to develop effective community-based ADV prevention/intervention program
Enigma of ultraluminous X-ray sources may be resolved by 3D-spectroscopy (MPFS data)
The ultraluminous X-ray sources (ULXs) were isolated in external galaxies for
the last 5 years. Their X-ray luminosities exceed 100-10000 times those of
brightest Milky Way black hole binaries and they are extremely variable. There
are two models for the ULXs, the best black hole candidates. 1. They are
supercritical accretion disks around a stellar mass black hole like that in
SS433, observed close to the disk axes. 2. They are Intermediate Mass Black
Holes (of 100-10000 solar masses). Critical observations which may throw light
upon the ULXs nature come from observations of nebulae around the ULXs. We
present results of 3D-spectroscopy of nebulae around several ULXs located in
galaxies at 3-6 Mpc distances. We found that the nebulae to be powered by their
central black holes. The nebulae are shocked and dynamically perturbed probably
by jets. The nebulae are compared with SS433 nebula (W50).Comment: Proceedings of the ESO and Euro3D Workshop "Science Perspectives for
3D Spectroscopy", Garching (Germany), October 10-14, 2005. M. Kissler-Patig,
M.M. Roth and J.R. Walsh (eds.
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