Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-37334) (for November 1995) OVERVIEW The YOHKOH Mission is a program of the Japanese Institute of Space and Astronautical Science (ISAS) with collaboration by the U. S. National Aeronautics and Space Administration and the U. K. Science and Engineering Research Council. The YOHKOH satellite was launched on 30 August 1991 from Kagoshima Space Center (KSC) in Japan. The purpose of this mission is to study high energy phenomena in solar flares and the Sun's corona. Under an international cooperative agreement, Lockheed, under NASA contract, is providing a scientific investigation using the Soft X-ray Telescope (SXT), one of the primary experiments of the mission. The SXT was developed at the Lockheed Palo Alto Research Laboratory in cooperation with the National Astronomical Observatory of Japan, and the Institute for Astronomy of the University of Tokyo. MAJOR PROGRAMMATIC ACTIVITIES IN THE MONTH Although the almost nine-year old contract is coming to a close, the SXT activities are still in full swing and a new contract will be initiated in January 1996. The benefits of SXT continue to reach out further. The Yohkoh Public Outreach Project (YPOP) effort was initiated this month with a very productive kick-off meeting at MSU. In addition, this month's Lockheed house paper, The Star, month had an extensive front page article about SXT and included a color image taken from our new poster. << Solar Activity >> November was marked by low solar activity. There were few active regions and only one C class flare (C2 on 10 November at 03:40 UT). A small active region (NOAA 7929) that emerged on 28 November produced two tiny jets on its western edge that were observed in the SXT partial field-of-view images at 10:00 and 10:30 UT on 30 November. There are many bright points present that can be clearly seen in coronal hole regions. << Campaigns >> There were no official Yohkoh campaigns during November. There were two special internal campaigns. Loren Acton initiated a campaign to take PFI exposures of the quiet corona near disk center away from any active Page 2 regions. This was done for two days and will be repeated sometime in December. In another campaign, high time resolution (4 second) PFI observations were obtained of a single active region using a single SXT filter. The unusual anemone shaped AR7929 was the target. These data will be used by David McKenzie of U. Delaware for investigation of wave heating of AR loops as part of his PhD thesis research. << Science >> Dr Ronald Moore (NASA-MSFC) ended his productive three-month visit to ISAS at the end of November. He found several good examples of eruptive events that appear to be consistent with Hirayama's sheared-core reconnection model. One new wrinkle in this pattern is the common occurrence of "elbows" at either end of the eruption; Ron speculates that this might reflect the field expansions seen in the simulations of sheared static fields by Antiochos et al. The group at ISAS has been busy on a number of scientific topics. Nariaki Nitta spent most of the month of November at ISAS and continued to work on super-hot flares, primarily from the imaging point of view. He found examples which show the super-hot emission even if the Fe XXVI Lyman alpha flux is not very high. Hugh Hudson has been working on HXT spectra of the superhot events in the Pike et al. list. Serge Savy has continued to develop his skills as an SXT chief observer and he is busy finishing a paper on SXT observations of chromospheric evaporation. Several people are working on the 11 July 1992 flare. Loren Acton spent November at ISAS and worked on several items to improve the ability to correct SXT images for observational artifacts. Since the additional entrance filter rupture in August '95 the stronger visible stray-light changed the pattern of stray-light in the thin aluminum images. This "grill" pattern was characterized and a method devised for including it in our routine stray-light correction images. (Acton noted that the filter ruptures have appreciably increased the SXT sensitivity at longer wavelengths, which is appropriate for the lower temperatures of solar minimum). The Lockheed group is happy to announce that Jean-Pierre Wuelser has joined their team. Jean-Pierre, who comes from the University of Hawaii, will continue to play a role in Mees operations. When he is not working on SXT related issues he will be working with Marilyn Bruner on various laboratory projects. Daniel Goldin, the NASA administrator, visited Montana State University during November, accompanied by Senator Conrad Burns of Montana. An SXT presentation was made by David Alexander which was apparently well appreciated by the administrator. Finally, the preparations for the AGU posters began this month. One of the invited posters is being led by Sam Freeland which will describe the unique Yohkoh software approach. We have also been invited to participate in the Page 3 Solar Terrestrial Theater, which will enable SXT movies to be displayed on a large (approx 10-foot) screen with high resolution. Special data formats are being prepared by G. Slater and J. Lemen. << Publications>> The publication list will be given next month. << Public Use of SXT Images >> We are continuing to make Yohkoh/SXT images available for a variety of uses. Efforts continue to make selected images available on the Lockheed SXT WWW homepage. During the month of November over 16,000 Yohkoh files on the Lockheed homepage were accessed from over 1300 sites. Gary Linford and Greg Slater worked on the new Yohkoh poster which will be prepared in time for distribution at the upcoming AGU meeting in San Francisco in early December. << Yohkoh Operations and Health >> Yohkoh and the SXT continue to function very well. There has been no further increase in the SXT straylight since 16-Aug-1995. The quiet patrol image has been changed to Al/Mg (DPE=17) to try to improve the performance of the active region selection algorithm for times when the Sun is very quiet. A CCD bake-out was conducted on 22 November, after which the CCD was cooled again to -20C. SXT experienced a normal level of Single Event Upset (SEU) events during the month: SXT bitmap error 09-Nov-95 Pass 1; 951108-1135 recovered in the same pass SXT SEU 17-Nov-95 Pass 1; 951117-0927 recovered in the next pass Page 4 << Data Flow >> ------------------------------------------------------------------------------ Month Full Frame Images Observing Region Images Received Lost Received Lost Loss % QT FL Tot Thru Aug-93 152714 71186 630455 249580 880035 331706 27.12 Sep-93 6875 2899 22697 5600 28297 11252 28.45 Oct-93 7474 3657 33782 7548 41330 20104 32.72 Nov-93 8504 3864 42953 5849 48802 23896 32.87 Dec-93 5898 3047 21128 13297 34425 13001 27.41 Jan-94 6934 2804 28567 10960 39527 13746 25.80 Feb-94 7000 2840 23021 5819 28840 11257 28.07 Mar-94 7736 2627 69273 3733 73006 31464 30.12 Apr-94 6142 2741 22707 3390 26097 12338 32.10 May-94 7070 2679 25260 3040 28300 10862 27.74 Jun-94 7417 2738 36795 1996 38791 15760 28.89 Jul-94 7488 2941 50540 3275 53815 24153 30.98 Aug-94 7370 2337 35067 3993 39060 13485 25.66 Sep-94 7079 2552 25131 2855 27986 10677 27.62 Oct-94 7244 2497 25868 5884 31752 10319 24.53 Nov-94 6569 1941 26243 1956 28199 9293 24.79 Dec-94 6429 2456 26763 2583 29346 11904 28.86 Jan-95 6870 2349 26103 1699 27802 10211 26.86 Feb-95 6556 2545 23635 3825 27460 10111 26.91 Mar-95 5915 2082 21485 3448 24933 8485 25.39 Apr-95 6244 2266 22946 4493 27439 9688 26.09 May-95 7084 2884 29617 2647 32264 15331 32.21 Jun-95 7210 3087 25251 307 25558 12045 32.03 Jul-95 6418 4145 21180 1639 22819 15109 39.84 Aug-95 7683 2597 26115 2181 28296 10537 27.13 Sep-95 6546 2853 22006 1753 23759 10433 30.51 Oct-95 6175 3233 19545 3853 23398 12016 33.93 Nov-95 0 0 0 0 0 0 0.00 Dec-95 0 0 0 0 0 0 0.00 Total 332644 143847 1384133 357203 1741336 689183 28.36 Number of Full Frame Images Received: 332644 Number of Observing Region Images Received: 1741336 Total: 2073980 Approximate Number of Shutter Moves/CCD Readouts: 3645110 NOTES: * The loss of images is mainly due to BDR overwrites, but there are also occasional DSN dumps which are lost. * It is common to have observing regions which contain more than 64 lines, which requires multiple exposures to make a single observing region image. This is why the number of shutter moves is larger than the number of images received plus those lost. Page 5 << Engineering Summary Table >> -------------------------------------------------------------------------------- Month Avg Dark Level # of Dark Spikes CCD Warmings Front Optical (DN) (e/sec) Over 48 Over 64 High / # Support Trans Temp /Days Temp (%) Sep-93 45.07 546.2 27469 2745 17.5 N/A Oct-93 45.40 558.6 31684 2982 17.7 N/A Nov-93 45.33 555.8 32047 3210 23.8 / 3 19.7 N/A Dec-93 45.92 578.1 38515 3101 19.2 N/A Jan-94 46.00 580.9 39074 3088 22.5 / 2 20.3 N/A Feb-94 46.03 582.1 40449 3246 19.3 N/A Mar-94 45.92 578.0 39715 3420 18.2 N/A Apr-94 45.97 579.9 41302 3721 25.2 / 3 17.8 N/A May-94 46.25 590.3 45476 3557 18.3 N/A Jun-94 45.83 574.6 39340 3547 17.8 N/A Jul-94 46.76 609.5 53417 3990 18.2 N/A Aug-94 46.98 617.6 57624 4050 25.2 / 3 18.2 N/A Sep-94 47.07 620.9 58580 4028 18.3 N/A Oct-94 47.34 631.3 64974 4346 19.0 N/A Nov-94 47.64 642.4 70877 4703 20.4 N/A Dec-94 47.82 649.1 74246 4917 21.5 N/A Jan-95 48.55 676.7 89758 5457 20.0 N/A Feb-95 48.70 682.1 92457 5781 25.2 / 3 20.5 N/A Mar-95 48.35 668.9 85527 5271 19.4 N/A Apr-95 48.72 682.8 93904 5627 19.1 N/A May-95 48.73 683.4 94000 5820 18.8 N/A Jun-95 49.08 696.3 100780 6281 19.6 N/A Jul-95 49.34 706.2 106408 6628 18.1 N/A Aug-95 49.72 720.4 114414 7101 19.5 N/A Sep-95 49.79 723.1 115165 7222 19.6 N/A Oct-95 50.24 739.8 125540 7786 20.0 N/A Nov-95 N/A N/A N/A N/A 0.0 N/A Dec-95 N/A N/A N/A N/A 0.0 N/A NOTES: * The dark current calculations are using full half resolution 2.668 sec images not taken in during the SAA. The dark current rate assumes a "fat zero" of 30.5 DN and a gain of 100 e/DN. * The entrance filter failure of 13-Nov-92 eliminated the capability of taking optical images, so the optical transmission is not available after Nov-92. It also caused an increase in the dark current signal, however some of the increase shown here is an increase in the readout noise and is not a function of exposure duration. Page 6 << Personnel Travel >> SXT Foreign Travel between 1-NOV-95 and 30-NOV-95 ACTON 1-NOV-95 * 30-NOV-95 * 30 (total of 30 days) HUDSON 1-NOV-95 * 19-NOV-95 19 27-NOV-95 30-NOV-95 * 4 (total of 23 days) NITTA 13-NOV-95 30-NOV-95 * 18 (total of 18 days) SAVY 1-NOV-95 * 30-NOV-95 * 30 (total of 30 days) SHING 1-NOV-95 * 3-NOV-95 3 (total of 3 days) ---------------------------------------------------------------- Grand Total of 104 days for 5 people NOTE: The "*" signifies travel that actually ends after 30-NOV-95 SXT Foreign Travel between 1-DEC-95 and 31-DEC-95 ACTON 1-DEC-95 * 3-DEC-95 3 (total of 3 days) HUDSON 1-DEC-95 * 10-DEC-95 10 27-DEC-95 31-DEC-95 * 5 (total of 15 days) LINFORD 7-DEC-95 21-DEC-95 15 (total of 15 days) NITTA 1-DEC-95 * 8-DEC-95 8 (total of 8 days) SAVY 1-DEC-95 * 31-DEC-95 * 31 (total of 31 days) ---------------------------------------------------------------- Grand Total of 72 days for 5 people NOTE: The "*" signifies travel that actually ends after 31-DEC-95 Respectfully submitted, James R. Lemen Frank M. Friedlaender Page 7 ------------------------------------------------------------------------------- NASA REPORT DOCUMENTATION PAGE (IN LIEU OF NASA FORM 1626) --------------------|--------------------------|------------------------------- 1. REPORT NO. | 2. GOVERNMENT | 3. RECIPIENT'S DR-01 | ACCESSION NO. | CATALOG NO. --------------------|--------------------------|------------------------------- 4. TITLE AND SUBTITLE | 5. REPORT DATE Monthly progress report - for the month of | 8 October 1995 November 1995 |------------------------------- | 6. PERFORMING ORG | CODE: O/91-30 -----------------------------------------------|------------------------------- 7. AUTHOR(S) | 8. PERFORMING ORGANIZA- J. R. Lemen | TION REPORT NO: F. M. Friedlaender | |------------------------------- -----------------------------------------------|10. WORK UNIT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS | Lockheed Palo Alto Research Labs B/252 |------------------------------- Solar & Astrophysics Laboratory O/91-30 |11. CONTRACT OR GRANT NO. 3251 Hanover Street, Palo Alto Ca. 94304 | NAS8 - 37334 -----------------------------------------------|------------------------------- 12. SPONSORING AGENCY NAME AND ADDRESS |13. TYPE OF REPORT AND Marshall Space Flight Center (Explorer Program)| PERIOD COVERED Huntsville Alabama 35812 | Progress report for the month | of November 1995 |------------------------------- |14. SPONSORING AGENCY | CODE MSFC / AP32 -----------------------------------------------|------------------------------- 15. SUPPLEMENTARY NOTES ------------------------------------------------------------------------------- 16. ABSTRACT The SOLAR-A Mission is a program of the Institute of Space and Astronautical Science (ISAS), the Japanese agency for scientific space activity. The SOLAR-A satellite was launched on August 30, 1991, to study high energy phenomena in solar flares. As an international cooperative agreement, Lockheed, under NASA contract, is providing a scientific investigation and has prepared the Soft X-ray Telescope (SXT), one of the two primary experiments of the mission. --------------------------------------|---------------------------------------- 17. KEY WORDS (SUGGESTED BY | 18. DISTRIBUTION STATEMENT AUTHOR(S)) Solar-A, X-ray, CCD, | Space Science, Solar Physics ------------------------|-------------|----------|-----------------|----------- 19. SECURITY CLASSIF. | 20. SECURITY CLASSIF. | 21. NO OF PAGES |22. PRICE (OF THIS REPORT) | (OF THIS PAGE) | | None | None | 7 | ------------------------|------------------------|-----------------|----------- For sale by: Superintendent of Documents, U.S. Government Printing Office