SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 44, ISSUE 1 - January 13, 2006

90 ASTROPHYSICS
Includes cosmology; celestial mechanics; space plasmas; and interstellar and interplanetary gases and dust.

20060000044 Consejo Superior de Investigaciones Cientificas, Madrid, Spain

Dissociative Shocks in the Neighborhood of Orion IRc2 Traced with Atomic Carbon

Pardo, Juan R.; Cernicharo, Jose; Phillips, Thomas G.; [2005]; 12 pp.; In English; Original contains black and white illustrations Contract(s)/Grant(s): AYA2000-1784; ESP2001-4516; AYA2003-2785; NSF AST-99-80846; Copyright; Avail.: Other Sources

We present Caltech Submillimeter Observatory 10' resolution maps of the 3P2(approaches)3P1 line of neutral atomic carbon (809.3435 GHz) and the J=7-6 line of CO (806.6518 GHz) covering a region of 2 x4.5 around Orion IRc2 in the BN/KL nebula. The two lines were observed with the same receiver, simultaneously, and therefore the two maps have zero relative pointing error. The atomic carbon (CI) emission does not peak toward the IRc2 position and displays a very different spatial distribution with respect to most molecular species. Moderately strong red wings are detected in CI around the region defined by the high velocity CO gas with a spatial distribution that delineates a shell of approx. 20' radius. We propose that CO dissociation in the J-type shocks produced by the interaction of the lRc2 outflows with the surrounding quiescent gas could play a significant role in this enhancement of atomic carbon in that shell. Author

Submillimeter Waves; Molecular Gases; Dissociation; Astronomical Observatories; Carbon; Atmospheric Chemistry

20060000070 Gemini Observatory, Hilo, HI, USA

NIFS Sees First Light

Beck, Tracy; McGregor, Peter; Gemini Focus: Newsletter of the Gemini Observatory; December 2005, pp. 48; In English; See also 20060000060; Copyright; Avail.: Other Sources

The Near-Infrared Integral Field Spectrograph (NIFS) first observed the night sky over Mauna Kea during the early evening hours of October 18, 2005. A tremendous team effort by staff from the Gemini Observatory and the Australian National University (ANU) allowed first light with NIFS to occur before the end of evening twilight. The first star observed was centered within 0.2 arcseconds of the center of the NIFS field. This is a remarkable feat considering the fact that the NIFS IFU has a very small field of view. NIFS is an image-slicing integral field unit built by the Research School of Astronomy and used exclusively with the Gemini North facility adaptive optics system ALTAIR. It delivers R approx. 5000 imaging spectra over a small 3 x 3 arcsecond field of view on the sky. The NIFS delivery to Gemini North comes just two and a half years after its predecessor was destroyed in the fires that raged through Canberra, Australia in January 2003. NIFS will be a powerful new tool to study the structure and kinematics of a wide range of astronomical targets, from the search for black holes in the center of galaxies to the ability to resolve structures on the surfaces of planets in our own solar system. The on-sky commissioning has progressed smoothly and is scheduled to be completed before the publication of this newsletter. A Gemini community call for System Verification (SV) proposals with NIFS will be released in early December 2005 and SV observations will be carried out during scheduled time in January 2006. Derived from text

Near Infrared Radiation; Spectrographs; Black Holes (Astronomy); Planetary Surfaces; Solar System

20060001815 Air Force Research Lab., Hanscom AFB, MA USA

Timescale for Radiation Belt Electron

Horne, Richard B.; Thorne, Richard M.; Glauert, Sarah A.; Albert, Jay M.; Meredith, Nigel P.; Anderson, Roger R.; Mar. 31, 2005; 11 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): Proj-1010 Report No.(s): AD-A440297; AFRL-VS-HA-TR-2005-1079; No Copyright; Avail.: CASI: A03, Hardcopy

Electron acceleration inside the Earth's magnetosphere is required to explain increases in the-MeV radiation belt electron flux during magnetically disturbed periods. Recent studies show that electron acceleration by whistler mode chorus waves becomes most efficient just outside the plasmapause, near L = 4.5, where peaks in the electron phase space density are observed. We present CRRES data on the spatial distribution of chorus emissions during active conditions. The wave data are used to calculate the pitch angle and energy diffusion rates in three magnetic local time (MLT) sectors and to obtain a timescale for acceleration. We show that chorus emissions in the prenoon sector accelerate electrons most efficiently at latitudes above 15 degrees for equatorial pitch angles between 20 degrees and 60 degrees. As electrons drift around the earth, they are scattered to large pitch angles and further accelerated by chorus on the nightside in the equatorial region. The timescale to accelerate electrons by whistler mode chorus and increase the flux at 1 MeV by an order of magnitude is approximately 1 day, in agreement with satellite observations during the recovery phase of storms During wave acceleration the electrons undergo many drift orbits and the resulting pitch angle distributions are energy-dependent. Chorus scattering should produce pitch angle distributions that are either flat-topped or butterfly-shaped. The results provide strong support for the wave acceleration theory. DTIC

Artificial Satellites; Electron Accelerators; Radiation Belts

20060002475 Lawrence Livermore National Lab., Livermore, CA USA

Science Day 2005 Poster Abstracts: Astrophysics

Kline, K. M.; Apr. 07, 2005; 12 pp.; In English Report No.(s): DE2005-15016429; UCRL-PROC-211169; No Copyright; Avail.: Department of Energy Information Bridge

The document is a collection of abstracts of posters and exhibits on the subject of astrophysics. NTIS

Astrophysics; Science

Source: NASA.