SUMMARY OF SEQUENCE NUMBER 600087

SUMMARY OF SEQUENCE NUMBER 600087

Title: RESOLVING THE MYSTERY OF X-RAY FAINT ELLIPTICAL GALAXIES

Observer: SARAZIN

Subject Category: Normal Galaxies

Seq: 600087 ObsId: 00784

Long-term Plan bin: 12-Jan-2000

ABSTRACT

We propose AXAF observations to spatially resolve the emission from X-ray faint early-type galaxies. Their X-ray emission mechanism is not well understood. Unlike the X-ray bright ellipticals in which most of the emission is from hot interstellar gas with T~1 keV, X-ray faint galaxies have hard (~5keV) and very soft (~0.2keV) spectral components. The hard component is assumed to be from low mass X-ray binaries (LMXBs), but the origin of the very soft component is mysterious. We suggested that LMXBs also produce the very soft emission, as it is seen in nearby LMXBs in our Galaxy and in the bulge of M31. These observations should resolve the soft and hard emission into individual sources, and will determine the spectral properties of the LMXBs and/or diffuse thermal gas in these galaxies.

TARGET SUMMARY

TARGET NAME RADEC TIME SI GRAT TYPE TC ROLL PRE PHASE MULTI PRI
NGC 4697
192.145833
-5.789167
40.00000
ACIS-S
NONE
GO
no
no
no
no
no
5

IMAGES

(NOTE: RASS images currently only available for targets LTS scheduled on or after Apr-09-2000)

Roll/Visibility

PARAMETERS

Obscat Parameters