From ssm@latte.msfc.nasa.gov Tue Apr 1 01:07:05 1997 Received: from space.mit.edu by wiwaxia AA20337; Tue, 1 Apr 97 01:07:03 EST Received: from head-cfa (head-cfa.harvard.edu) by space.mit.edu AA19282; Tue, 1 Apr 97 01:07:02 EST Received: from latte.msfc.nasa.gov by head-cfa (SMI-8.6/SMI-SVR4) id BAA13407; Tue, 1 Apr 1997 01:05:35 -0500 Received: from latte.msfc.nasa.gov (ssm@localhost [127.0.0.1]) by latte.msfc.nasa.gov (8.7.5/8.7.3) with ESMTP id GAA07351 for ; Tue, 1 Apr 1997 06:06:01 GMT Message-Id: <199704010606.GAA07351@latte.msfc.nasa.gov> To: head@head-cfa.harvard.edu Subject: HRC Status Report #(5,6,???) Date: Tue, 01 Apr 1997 06:06:01 +0000 From: "Stephen S. Murray" Status: R Another day and another series of tests have been run. We are now using the EIPS sources to measure the response of the newly renamed Murray/Drake flats in honor of the fact that these high energy supression filters mainly work, but are not exactly where we thought they were. Actually, the flats do appear to be doing the job of supressing high energies, and the initial tests show that they have pretty good surface properties as well as decent reflectivity at low energy. A lot of careful analysis will be needed to figure out exactly what the refelctivity versus energy and angle is for these flats, but we do at least have a ton of data to work with. In addition to these "SM" measurements of the flats, we have been using the LETGS for understanding the input spectrum of each EIPS source and also to calibrate the LETGS directly. The grating spectra on the HRC-S are truly magnificant. Peter will have a wonderful time analyzing these data out to 13-th order and more! I hope we can make some nice images of the grating data to show off. Meantime look to Peter's WWW page. An very nice result was obtained from the C-Ka count rate linearity data. We have an on-axis, in focus image where we can resolve the slight asymmetry of the HRMA, even with only a few hundred counts. The core is probably not resolved by the HRC, which has a formal FWHM of 20 microns or just under 1/2 arc second. We measure a FWHM for the telescope of about that amount. Both HRC-I and HRC-S are being used in these EIPS tests, and with higher energy sources we are making a few HETGS and METGS measurements also. The results have not been studied in detail since the HETGS/METGS scientists are in Cambridge, but the pictures are very nice! We do notice that the MCP gain variations in HRC-I and HRC-S are going to be a problem in the analysis of data so we have been pressing to get better flat fields of both detectors while we are here at MSFC. We will also try to look at the sensitivity of the flat fields to the MCP operating voltage, as this will likely be changed in orbit over the AXAF lifetime. The HRC teams are going to be rotating out (FINALLY) and a few of use who have been here for 6 weeks are going to return to Cambridge for a little while (once the snows melt) to catch up with other business and reaquaint ourselves with the folks at home. Please stop by and say hello and see some of our data! Steve Dr. Stephen S. Murray - Sr. Astrophysicist Associate Director - High Energy Astrophysics Division _______________________________________*_______________________________________ Smithsonian Astrophysical Observatory__| phone: (617) 495-7205 High Energy Astrophysics Division __| fax: (617) 495-7356 60 Garden Street, MS-2 __| email: ssm@head-cfa.harvard.edu Cambridge, MA 02138 __| http://hea-www.harvard.edu/~ssm/HomePage.html ___________________________|___________________________________________________