1/4 keV Fluctuations Due to the Local Hot Bubble
Abstract
As part of a program to characterize 1/4 keV fluctuations at high galactic latitudes, such as those discovered by Barber, Warwick, & Snowden (1995), it is necessary to characterize the fluctuations produced by the principal foreground components of the 1/4 keV background, the Local Hot Bubble. To do so, we are studying a substantial number of deep, overlapping ROSAT PSPC pointings towards the Hyades cluster, a region which has a substantial absorbing column outside the LHB that effectively blocks the distant 1/4 keV emission. Absorption of X-ray emission by clouds within the LHB is thought to be small in this direction and can be determined by modeling the ROSAT response function. The structure of the X-ray emission in this field can be caused by 1.) changes in the pathlength to the LHB boundary, and 2.) variation in emission measure within the LHB. The amplitude of fluctuations can then place limits on these quantities, but cannot separate their effects.
- Publication:
-
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 1997
- Bibcode:
- 1997AAS...191.5108K