Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-40801) (for October 1999) 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 Martin, 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 Martin Solar and Astrophysics 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 The end of the contract is now clearly in sight. It is important that the RFP for the extension of data analysis and operations be released in the near future. SOLAR ACTIVITY In early October, solar activity started out very quiet, with few flares of any sort to report. Activity picked up slightly with a number of mildly flaring active regions appearing from over the east limb. In mid-October, solar activity remained low, with the GOES background level staying at or below C1 and only two flares above C3. The activity picked up briefly, however, when an X1.8 flare occurred on 14-OCT-99 at 08:54. No other M or X class flares were observed. The X-ray baseline climbed slowly, reaching C-level at the end of the period. In late October, an M1.7 flare occurred on 20-OCT, while SXT was in PFI-dominant mode and fixed pointing for JOP 113 -- SXT acquired data in the preflare and impulsive phases of this and several smaller (C-class) flares. High levels of geomagnetic activity were recorded on 22-Oct-99. Active regions 8737, 8739, 8741 and 8742 produced several good M flares and C flares, including one M3.7 event on the west limb. The most spectacular event of the interval was the nuggetized event of October 26 which appeared to have an over-the-loop hard X-ray source. CAMPAIGNS Yohkoh/SXT participated in JOP 103 ("Moss") in collaboration with La Palma, Page 2 TRACE, MDI, CDS and SUMER on 6-7 October. Yohkoh/SXT supported a campaign led by Brigitte Schmieder to observe the signatures of emerging flux and arch filament systems, from 11-oct to 17-oct. Yohkoh/SXT participated in JOP 113 in collaboration with TRACE and several ground-based observatories from 19-October onward. This campaign is intended to make images of flares with high temporal and spatial resolution. Several M-class and several C-class flares have been observed as part of this ongoing JOP. We also supported the resurrection of JOP 104, begun in May 1999, as SUMER entered high telemetry mode in an attempt to observe Doppler shifts during eruptive events (like flares and jets). We increased the number of flares jointly observed by SUMER, SXT, and TRACE, plus numerous GBOs. As an informal campaign we attempted to get special observations related to NS interconnecting loops, hoping of course for a TILDE (trans-equatorial interconnecting loop disappearance event), as happened during the flares of May 1998. SCIENCE Alexander Worked on chromospheric evaporation studies in the late phase of solar flares with Czaykowska. The lack of hard X-ray emission coupled to the presence of evaporation flows late in the flare places limits on the energetic electron production from the continuing reconnection. Canfield continued gathering data from SXT, HXT, and other spacecraft and ground-based observatories to determine which flare events occurred and were well observed in the region chosen for the Max Millennium (MMOC 002) and SOHO (JOP 106) sigmoids campaign, AR 8668. Evaluation of the research potential of observations secured during the campaign is still in progress. Canfield and Van Lew have gotten off to a good start on their study of observations of SXT jet / MCCD surge events by reviewing AR 7260, a region (from KD Leka's thesis work) in which many such events were well observed. As of this time, MCCD velocity movies of all events in this region have been produced and the initial review of events to determine the handedness of their spin is complete. Analysis of other regions remains to be done. Nitta Continued working on the relation between SXT and TRACE loops. This required a manual coalignment of SXT/TRACE images using EIT 195 A images. Nitta found that mechanical coalignment purely based on the header information can give an error as large as ~15" and that roll corrections are not negligible. During the course of the manual coalignment, he confirmed that the SXT pixel size (in X-rays) is between 2.455" and 2.460", by looking at the mission-long SXC database. Page 3 Weber Finished a draft on "Bimodal Behavior in Solar Rotation Rates", with Longcope. SXT data shows that the south polar coronal hole extension alternated abruptly between two rotation modes. Using the flux-transport model of Sheeley, Nash, & Wang, he developed an analytic approximation for the surface flux distribution and shows how one of the modes is a consequence of the presence of an "activity nest". 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 LMSAL SXT WWW homepage (http://www.lmsal.com/SXT/). We receive requests for the Yohkoh posters (#2 and #3) by way of the form on the SXT homepage. Currently we receive requests via our homepage at the rate of 2 or 3 per day. The WEB access statistics in October were 98501 accesses and 5228 Mbytes transferred. YOHKOH OPERATIONS AND HEALTH Yohkoh and the SXT continue to function very well. SXT experienced a normal level of Single Event Upset (SEU) events during the month: Unknown SXT Error 09-Oct-99 Pass 5: 991009-1031 Recovered in Pass 2 the next day SXT Bit Map Error 25-Oct-99 Pass 1: 991025-0104 Recovered in the same pass Page 4 DATA FLOW Month Full Frame Images Observing Region Images Received Lost Received Lost Loss % QT FL Tot Thru Aug-97 485804 192865 1965355 398535 2363890 917015 27.70 Sep-97 7051 1479 33646 9596 43242 8887 17.05 Oct-97 7023 1134 26813 1827 28640 6043 17.42 Nov-97 6691 1376 26297 15306 41603 7131 14.63 Dec-97 6806 1013 28472 2136 30608 5263 14.67 Jan-98 5715 1803 23479 3232 26711 9918 27.08 Feb-98 6606 1644 25257 3606 28863 8989 23.75 Mar-98 6043 2056 23029 10399 33428 10939 24.66 Apr-98 6537 1103 22656 8087 30743 6339 17.09 May-98 7569 1838 28292 19018 47310 9868 17.26 Jun-98 6463 1638 24990 5618 30608 9051 22.82 Jul-98 6810 1892 27046 7357 34403 9970 22.47 Aug-98 5823 1960 22978 14126 37104 11167 23.13 Sep-98 6776 1432 21814 11626 33440 7753 18.82 Oct-98 6573 1901 23520 5198 28718 9220 24.30 Nov-98 6442 1695 25124 26948 52072 9920 16.00 Dec-98 5962 2005 21490 15770 37260 10561 22.08 Jan-99 5494 1825 20087 17620 37707 9622 20.33 Feb-99 5729 1525 30802 9798 40600 10630 20.75 Mar-99 6807 1844 24721 12354 37075 10064 21.35 Apr-99 6715 1371 25113 4179 29292 7791 21.01 May-99 6459 1807 35467 12092 47559 13757 22.44 Jun-99 6217 1915 23542 13051 36593 10086 21.61 Jul-99 5591 1745 20409 25747 46156 9670 17.32 Aug-99 6827 2503 21725 23361 45086 11844 20.80 Sep-99 5768 2011 21890 3434 25324 10846 29.99 Oct-99 4336 1820 16257 5286 21543 8709 28.79 Nov-99 0 0 0 0 0 0 -NaN Total 650637 237200 2610271 685307 3295578 1161053 26.05 Number of Full Frame Images Received: 650637 Number of Observing Region Images Received: 3295578 Total: 3946215 Approximate Number of Shutter Moves/CCD Readouts: 6750578 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-97 54.77 909.7 196501 17757 21.0 N/A Oct-97 54.85 912.8 198157 17857 21.5 N/A Nov-97 55.17 924.8 202153 18993 22.5 / 2 23.1 N/A Dec-97 55.51 937.6 206194 20219 21.9 N/A Jan-98 56.06 958.0 212189 22121 23.9 N/A Feb-98 55.94 953.7 209254 22122 23.8 / 2 22.6 N/A Mar-98 56.29 966.6 213519 23249 21.8 N/A Apr-98 56.44 972.1 214676 23890 20.8 N/A May-98 56.90 989.4 215651 26905 21.4 N/A Jun-98 57.11 997.5 216285 28223 20.1 N/A Jul-98 57.01 993.7 215499 27493 21.4 N/A Aug-98 57.36 1006.7 217355 29544 20.9 N/A Sep-98 57.43 1009.5 218520 29683 20.9 N/A Oct-98 57.59 1015.3 220504 30221 21.3 N/A Nov-98 58.17 1037.0 223755 34614 22.5 / 2 23.4 N/A Dec-98 57.86 1025.5 221918 32420 23.8 N/A Jan-99 58.74 1058.6 227503 38238 23.1 N/A Feb-99 58.44 1047.4 224002 36198 23.2 N/A Mar-99 59.26 1078.1 227900 43051 21.7 N/A Apr-99 58.82 1061.4 225973 38963 23.8 / 1 21.4 N/A May-99 58.68 1056.4 225385 37726 21.6 N/A Jun-99 59.40 1083.0 230091 42440 22.0 N/A Jul-99 59.78 1097.5 231236 46337 23.8 / 1 20.6 N/A Aug-99 59.39 1083.0 229319 43067 21.7 N/A Sep-99 60.04 1107.3 231585 49084 21.8 N/A Oct-99 59.65 1092.7 229713 45251 22.3 N/A Nov-99 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-OCT-99 and 31-OCT-99 CANFIELD 30-OCT-99 31-OCT-99 * 2 (total of 2 days) FLETCHER 11-OCT-99 31-OCT-99 * 21 (total of 21 days) HANDY 1-OCT-99 * 07-OCT-99 7 (total of 7 days) HUDSON 1-OCT-99 * 16-OCT-99 16 26-OCT-99 31-OCT-99 * 6 (total of 22 days) MCKENZIE 5-OCT-99 13-OCT-99 9 18-OCT-99 31-OCT-99 * 14 (total of 23 days) SHIRTS 1-OCT-99 * 24-OCT-99 24 (total of 24 days) ---------------------------------------------------------------- Grand Total of 99 days for 6 people NOTE: The "*" signifies travel that actually ends after 31-OCT-99 SXT Foreign Travel between 1-NOV-99 and 30-NOV-99 CANFIELD 1-NOV-99 * 12-NOV-99 12 (total of 12 days) FLETCHER 1-NOV-99 * 5-NOV-99 5 (total of 5 days) HUDSON 1-NOV-99 * 30-NOV-99 * 30 (total of 30 days) MCKENZIE 1-NOV-99 * 25-NOV-99 25 (total of 25 days) NITTA 10-NOV-99 26-NOV-99 17 (total of 17 days) SLATER 30-NOV-99 30-NOV-99 * 1 (total of 1 days) ---------------------------------------------------------------- Grand Total of 90 days for 6 people NOTE: The "*" signifies travel that actually ends after 30-NOV-99 Respectfully submitted, Thomas R. Metcalf Frank 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 | 10 November 1999 October 1999 |------------------------------- | 6. PERFORMING ORG | CODE: O/L9-41 -----------------------------------------------|------------------------------- 7. AUTHOR(S) | 8. PERFORMING ORGANIZA- T. R. Metcalf | TION REPORT NO: F. M. Friedlaender | |------------------------------- -----------------------------------------------|10. WORK UNIT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS | Lockheed Martin Missiles and Space |------------------------------- Advanced Technology Center, O/L9-41, B/252 |11. CONTRACT OR GRANT NO. 3251 Hanover Street, Palo Alto Ca. 94304 | NAS8 - 40801 -----------------------------------------------|------------------------------- 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 Contact: Larry Hill | of October 1999 |------------------------------- |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