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Limits on Emisson from Fe IX - X from the Hot Local Interstellar Medium

Limits on Emisson from Fe IX - X from the Hot Local Interstellar Medium. Dr. Jeffrey J. Bloch Space and Remote Sensing Sciences Group Los Alamos National Laboratory Jbloch@lanl.gov. Photon spectrum from an optically thin hot plasma as a function of temperature. The arrows

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Limits on Emisson from Fe IX - X from the Hot Local Interstellar Medium

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  1. Limits on Emisson from Fe IX - X from the Hot Local Interstellar Medium Dr. Jeffrey J. Bloch Space and Remote Sensing Sciences Group Los Alamos National Laboratory Jbloch@lanl.gov Space and Remote Sensing Sciences

  2. Photon spectrum from an optically thin hot plasma as a function of temperature. The arrows indicate the energy centers of the three ALEXIS telescope bandpasses. Space and Remote Sensing Sciences

  3. ALEXIS Satellite Space and Remote Sensing Sciences

  4. ALEXIS Telescope Cross Section Space and Remote Sensing Sciences

  5. ALEXIS All-Sky Mission Raw Count Map Telescopes 1B, 2B, 3A (171-190 Å) October 1993- November 1997 No Effective Exposure or Background Corrections Performed Space and Remote Sensing Sciences

  6. Analysis Strategy • Early sky maps showed no correlation with SXRB • Complex non-cosmic backgrounds complicated analysis • New Strategy: Use whole FOV of ALEXIS telescope as a “Light Bucket” for analysis. • Similar resolution to proportional counter maps • Use 0.5 second bin total rate scalar data for analysis • Constantly scanning mode of operation actually aids in removing local backgrounds. • Same point on sky measured many times with different local system parameters Space and Remote Sensing Sciences

  7. Calibration Strategy • End-to-End model constructed from component calibrations • Pencil beam absolute throughput calibrations compared with end-to-end simulations of same measurements. Instrument model adjusted until agreement reached. This determined absolute efficiency on-axis. • HZ 43 data used to correct relative vigneting function • Corrected Instrument model used to compute area-solid angle product curve. • Actual measured cosmic point source count rates compared to predicted rates using EUVE spectra used to verify instrument model. Space and Remote Sensing Sciences

  8. HZ 43 Count Rate as Function of Scan Position in FOV Space and Remote Sensing Sciences

  9. HZ 43 Count Rate as Function of Time Over Four Years Space and Remote Sensing Sciences

  10. Space and Remote Sensing Sciences

  11. Comparison of Predicted Source Rates with Actual Source Predicted Rate Observed Rate HZ 43 0.478 0.436 ± 0.03 Alpha Cen 0.0186 0.012 ± 0.004 G191 B2B 0.063 0.066 ± 0.002 Space and Remote Sensing Sciences

  12. Predicted ALEXIS 1B Average Sky Rate Space and Remote Sensing Sciences

  13. Complex Non-Cosmic Backgrounds Space and Remote Sensing Sciences

  14. Spin Period Modulation Related to Ram Vector Space and Remote Sensing Sciences

  15. Modeling the Particle Background Count rates under the Aluminum shadow masks on the outer edge of each microchannel plate detector as a function of “L” parameter for all of 1995. Space and Remote Sensing Sciences

  16. Modeling the He II 304 Angstrom Background Space and Remote Sensing Sciences

  17. ALEXIS Telescope Non-Cosmic Background Components Anomalous Background (Ion Induced?) Eliminated When Telescope Look Direction > 110° From Velocity Vector Trapped Penetrating Radiation Rate µ L Value (L<3) Ions? Telescope FOV (50 sec. Rotation) Fluorescently Scattered He II 304 Å Sunlight (He II Trapped in Magnetic Field) Space and Remote Sensing Sciences

  18. Fitting the Data to a Constant Sky Rate The solid histogram shows the distribution of parameter fit values for an average sky flux count rate over 81 datasets (5 days each) that pass the criteria discussed in the text. The dashed histogram shows the distribution that results from the same analysis applied to the same data but that had random count rate values added on to each rate scaler data point whose means were based on the expected count rate values from the global spectral model and the Wisconsin B band sky map. This plot demonstrates that had a cosmic sky flux of the expected magnitude been present in the data, this analysis technique would have detected it. Space and Remote Sensing Sciences

  19. Fitting the Data to a Ratio of ALEXIS to Wisconsin B Band Sky Rates The solid histogram shows the distribution of parameter fit values for an average ratio between an ALEXIS telescope 1B cosmic rate that is proportional to the Wisconsin B band count rate and the actual B band count rate for 5 day datasets that pass the criteria. The dashed histogram shows the distribution that results from the same analysis applied to the same data but that had random count rate values added on to each rate scaler data point whose means were based on the expected count rate values from the global spectral model and the fluxes in the Wisconsin B band map. This shows that had a cosmic sky flux of the expected magnitude and variation been present in the ALEXIS data, this analysis would have correctly recovered the correlation ratio between the two datasets. Space and Remote Sensing Sciences

  20. Acknowledgments ALEXIS is supported by the Department of Energy. The ALEXIS/Blackbeard Project Wishes to Thank: Los Alamos: Ron Aguilar, Frank Ameduri, Dolores Archuleta, Tom Armstrong, Rick Balsano, Al Beldring, Bruce Blevins, George Berzins, Mark Bibeault, Tom Butler , Doug Ciskoski, Don Cobb, Al Criscolo, Jim Devenport, Bob Dingler, Mel Duran, Brad Edwards, Don Enemark, Sandy Fletcher, John Gustafson, Irma Gonzales, Dave Guenther, Matt Hei, Amy McNeil, Dan Holden, Rick Hodson, Mark Hodgson, Meg Kennison, Becky King, Phil Klingner, Cindy Little, Lisa May, Bob Massey, Dave McComas, Jim Miller, Lee Morrison, Carter Munson, Greg Nunz, Gregg Obbink, John Passarelli, Paras Patel, Tim Pfafman, Mick Piotrowski, Bill Priedhorsky, Keri Ramsey, Diane Roussel-Dupre', Sean Ryan, Bob Scarlett, Jim Shipley, April Smith, Barham Smith, Steve Smoogen, Steve Stem, Ernie Serna, Ralph Stiglich, John Sutton, Earl Tech, Mike Ulibarri, Matthew Ward, and Steve Wallin AeroAstro, Inc., Sandia National Laboratory, The Space Test Program, NORAD, Space Command,... And Many More! Space and Remote Sensing Sciences

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