by National Aeronautics and Space Administration, National Technical Information Service, distributor in [Washington, DC, Springfield, Va .
Written in English
|Statement||Chanan, G.A., Novick, R|
|Series||NASA contractor report -- NASA CR-179899|
|Contributions||Novick, Robert, United States. National Aeronautics and Space Administration|
|The Physical Object|
For the purposes of making polarization measurements, a small beryllium scattering block (3 cm in diameter by cm long) was placed within the spectrometer cryostat, near the center of the Ge detector array ().The role of the Be block is to Compton scatter the solar flare hard X-rays (20– keV) into the rear segments of the adjacent Ge by: The motivation for high quality solar flare X-ray polarization measurements are discussed in general. The design of the proposed instrument is described and then the sensitivity and energy response are discussed. The laboratory work which demonstrates that the earlier lithium contamination problem was solved, is described. The history of solar flare X-ray polarimetry is reviewed and it is shown that as yet, there is no experimental evidence for such polarization. The present experimental limits are at the level of a few percent but these results may be biased by a large thermal component at low energies which may decrease the apparent polarization. To avoid this difficulty it will be Cited by: PROSPECTS FOR HARD X-RAY SOLAR FLARE POLARIMETRY WITH RHESSI M. L. McConnell 1, D. M. Smith 2, A. G. Emslie 3, R. P. Lin 2, and J. M. Ryan 1 1Space Science Center, University of New Hampshire, Durham, NH 2Space Sciences Laboratory, University of California, Berkeley, CA , USA 3Dept. of Physics, University of Alabama, Author: Mark L McConnell, D M Smith, A G Emslie, R P Lin, James M. Ryan.
Abstract. The scientific motivation for X-ray polarimetry is discussed with particular emphasis on the information that might be obtained on the binary X-ray pulsars in addition to a number of other classes of objects including solar by: 7. Lucia Kleint, December 1, Example: C flare time of IBIS observations (‐) C flare from ‐ An X-ray polarimeter can deliver for each time interval not only an energy spectrum of the X-ray flux F (E), but also the energy spectra of the X-ray polarization degree a 0 (E) and the X-ray. The begin time of an X-ray event is defined as the first minute, in a sequence of 4 minutes, of steep monotonic increase in nm flux. The X-ray event maximum is taken as the minute of the peak X-ray flux. The end time is the time when the flux level decays to a point halfway between the maximum flux and the pre-flare background level.
Now, solar X-ray wavelengths are monitored via satellite for solar flares. Flares are characterized by a rise time on the order of minutes and a decay on the order of tens of minutes. The total energy expended in a typical flare is about 10**30 ergs; the magnetic field is extraordinarily high, reaching values of to 10, gauss. X-RAY AND GAMMA-RAY POLARIMETRY White Paper Submission to Astro The Astronomy and Astrophysics Decadal Survey Thematic Science Area: Stars and Stellar Evolution Febru Contact Dr. Mark McConnell University of New Hampshire [email protected] phone: Contributors Dr. Matthew G. Baring Rice . We review the history of astronomical X-ray polarimetry based on the author’s perspective, beginning with early sounding-rocket experiments by Robert Novick at Columbia University and his team, of which the author was a member. After describing various early techniques for measuring X-ray polarization, we discuss the polarimeter aboard the Orbiting Solar Cited by: 4. E I //,A"' - 2 2 - CAL 4 FINAL SCIENTIFIC REPORT TITLE OF RESEARCH: NAGU 5aa Solar Flare X-ray Polarimetry PERIOD OF RESEARCH: April 1, to Septem SUBMITTED TO: National Aeronautics and Space Administration Headquarters Solar and Heliosperic Physics Office.