Project Title:

Thermal Design of a Precollimator

09.08-5710
Thermal Design of a Precollimator
Analytix Corporation
P.O. Box 4044, 1818 Blakefield Circle
Timonium
MD
21093
Noravian
Heros
301-321-5710
50730
29267
43,213
GSFC

Abstract:

The innovation involves the design of a system (to be referred to as a Thermal Precollimator)
to provide a thermal gradient in fron of grazing incidence X-ray telescopes while
minimizing obscuration of the telescope field-of-view.  The system should occupy
a minimum of space (3 inches) above the telescope and it should be designed not to
distort due to thermal gradients and thereby change the percentage of obscuration.
 The section of the telescope under investigation is its aperture which is consisted
of four individual (9O-degree) segments.  The reflecting surfaces (O,OO5 inch thin
polished--name plate finish--aluminum--type 1145), occupy the telescope aperture,
are placed concentrically with an average spacing of 1/16 of an inch.  The main concern
is the deformation (and, therefore, the obscuration of the telescope field-of-view)
of these reflecting surfacea due to thermal gradients.  Severe thermal gradients
may be developed, especially when the telescope is aimed at distant stars (deep space).
 This is due to the fact that the inner side of the aperture is faced towards a 2O
degree C environment (telescope interior), while the outer side is exposed to deep
space at -273 degree C.