Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-37334) (for the month of December, 1992) OVERVIEW 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 from Kagoshima Space Center (KSC) in Japan, and renamed Yohkoh. The purpose of this mission is to study high energy phenomena in solar flares. 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 by Lockheed in cooperation with the National Astronomical Observatory of Japan, and the Institute for Astronomy of the University of Tokyo. MAJOR ACTIVITIES IN THE MONTH << Solar Activity and Observation Planning >> We ended 1992 with the satisfaction of a very successful year of observing with SXT and Yohkoh. The first publications are now out and hard work is in progress in many places on the next round of papers. The SXT itself continues to perform without problems. Since losing the entrance filter in November we have been unable to acquire images from the aspect sensor. Mees Observatory quickly installed a full disk white light system on their spar to partially compensate for loss of this SXT data so that it will still be possible to accurately co-align the Yohkoh images with ground based data. Now that we have developed techniques for correcting for stray light in the x-ray images the prime function of the SXT is practically unaffected by the change in the entrance filters. Solar activity was very low during the month of December, consistent with the approaching solar minimum. There were numerous C flares observed by Yohkoh and 2 M flares on 4 Dec 1992 from NOAA AR 7352. Because of the low solar activity, a special X-ray Bright Point study was initiated with coordinated ground observations at KPNO organized by SXT Co-I Karen Harvey. At the end of December the HIREGS X-ray balloon payload (Dr. R. Lin, U.C. Berkeley) was prepared and launched from Antarctica. This balloon has as its primary mission the observation of flares. The flight will continue until about the middle of January 1993 (depending on the winds at the South Pole), making it very possible that Yohkoh and HIREGS may jointly observe one or more flares. The Yohkoh year-end spacecraft operation holiday occurred 29 Jan 92 until 4 Jan 993. During this time there were no real-time operations at KSC or ISAS. A minimum observing plan was uploaded which enabled SXT to obtain images for approximately two orbits a day at quarter resolution, in order to maintain the long-term synoptic movie. Telemetry dumps were accomplished through the DSN << Data Analysis Software >> SXT Instrument Sensitivity: Calibration data for the SXT mirror reflectivity (data from MSFC2) was reviewed and the wavelength dependent mirror effective area was recalculated. The results of this review are summarized in SXT Calibration Note #30 by J.R.Lemen. We expect to incorporate these refined values into the SXT instrument sensitivity function and regenerate the SXT effective area data base files in early January. BCS Conversion routines: Routines were written to convert BCS calibrated spectral files (BSC files) into a format compatible with the rest of the Yohkoh IDL based analysis system. This work is consistent with, and fully complements the current effort by the BCS team to convert much of the BCS analysis software from Fortran into IDL. The primary goal in these efforts is to further enhance the existing capabilities to analyze data from all Yohkoh instruments in a coordinated fashion. Yohkoh SW System Support: To support the recent reorganization of the distributed Yohkoh software package, additional utilities are under development to track and monitor the literally thousands of IDL routines available for Yohkoh data analysis. This work will continue into January with the primary goals of facilitating remote site software upgrades and providing additional online help for SW users and contributors. The increasing number of software contributors and the associated growth of the online Yohkoh data analysis system requires these added capabilities to avoid potential conflicts among the SW modules and to allow users to efficiently identify the subset of routines which are required for there particular requirement. There are currently 21 sites which have installed the Yohkoh data analysis software system. SXT Scattered Light Correction: Two new data base files were defined in response to the increase in SXT scattered light due to the failure of an entrance filter(s). These files are now automatically generated from the reformatted data to monitor the scattered light levels. Software has already been written to use this data base for automatic correction of SXT images by subtraction of corresponding scattered light calibration images. Some visitors during the AGU conference were so impressed with the general Yohkoh IDL display package XSTEPPER that they asked for copies to be sent to their institutions. The package was written in such a manner that it could work on other experimental data with no modifications to the software at all. << Instrument Operations and Health >> The microprocessor of SXTE-U continues to operate well. Only one unrecoverable SEU has been detected since the SXTE-U flight software was enhanced in late March 1992 to include a self SEU detection/correction algorithm. This compares very favorably with more than 20 events noted in the corresponding period in the previous year. Many of those earlier events caused multiple orbit interruptions in SXT observations as well as placing increased demands on the SXT operational personnel. This improved performance combined with the automation of the KSC reformatting were the primary reasons that the decision was made to allow SXT to operate without supervision for several days over the holiday period. << Data Flow >> Operations and Flight Software: Reformatting of near real time data from KSC contact and playback data was fully automated in December. This has resulted in a significant reduction in the labour intensive duties of the SXT duty scientists (aka: SXT Tobans) This allows more time to be spent on review and analysis of near real time SXT images rather than on the production of the data - this in turn should allow more efficient identification of potential problems in SXT observing sequences and increase the scientific return potential of SXT. Magneto-Optical disk drives (MO Disks) have been purchased and installed at ISAS. Disks for these should be available by mid to late January. At that time, we will begin using these as storage/work media for the Yohkoh reformatted data base at ISAS. The strategy for incorporating these disks is currently under discussion. The first (and long awaited) tape containing SOON data from sites around the world should be sent to LPARL in mid January. We plan to generate a catalog from these tapes which is consistent in structure with the rest of the Yohkoh data base. Such a catalog will make it trivial to (for example) extract the SOON H-Alpha image closest in time to a selected SXT image (or HXT image, BCS Spectra...etc.) << Papers and Conferences >> The fall meeting of the AGU, held in San Francisco, contained a solar session at which several Yohkoh-SXT posters were presented. Four of the posters had video displays and a workstation provided the ability to display high-resolution SXT images. The posters generated much interest and there were many useful discussions at the poster session. The following day several AGU attendees visited LPARL to continue discussions about the Yohkoh data and to plan future analysis collaborations. << Personnel Travel >> The following was the travel for the SXT team for December, 1992: ACTON 1-DEC-92 * 10-DEC-92 10 (total of 10 days) HUDSON 1-DEC-92 * 2-DEC-92 2 7-DEC-92 31-DEC-92 * 25 (total of 27 days) NITTA 1-DEC-92 * 28-DEC-92 28 (total of 28 days) SLATER 1-DEC-92 * 21-DEC-92 21 (total of 21 days) The following is the travel planned for the SXT team for January, 1993: ACTON 5-JAN-93 17-JAN-93 13 (total of 13 days) HUDSON 1-JAN-93 * 31-JAN-93 * 31 (total of 31 days) LINFORD 5-JAN-93 31-JAN-93 * 27 (total of 27 days) NITTA 15-JAN-93 31-JAN-93 * 17 (total of 17 days) SLATER 11-JAN-93 26-JAN-93 16 (total of 16 days) STRONG 5-JAN-93 31-JAN-93 27 (total of 27 days) CANFIELD 1-JAN-93 31-JAN-93 * 31 (total of 31 days) Respectfully submitted, Mons D. Morrison Frank Friedlaender Page ?? -------------------------------------------------------------------------------- UNIVERSITY OF HAWAII ACTIVITY REPORT (DR. R. CANFIELD) MAJOR ACTIVITIES FOR THE MONTHS OF NOVEMBER AND DECEMBER Our most important Yohkoh activities were Yohkoh operations, Mees operations, data analysis and software development in Hawaii and Japan, a workshop, and development of a full-Sun white-light capability at Mees. The Mees observers continued full-day observations in support of Yohkoh. Hudson supported SXT operations in Japan, and Mickey, Leka, Metcalf, Wuelser, and Canfield served as Yohkoh Duty Scientist in Hawaii. The Imaging Vector Magnetograph was used for flare H-alpha linear polarization observations, to search for possible signatures of precipitating protons. During Acton's three-week visit, he and Canfield organized the first Hawaii Coordinated Data Analysis Workshop (CDAW). Yohkoh and ground-based observations of two well-observed large flares (1991 October 24 and 1991 November 15) were discussed. Considerable progress was made in reaching a common understanding of the basic flare properties, and several open questions were identified for discussion at the Yohkoh workshop in February. With various collaborators, Hudson worked on impulsive footpoint brightenings and subsequent main-phase flare soft X-ray emission. With Bachtiar and McClymont he worked on sunspot proper motions. With various GRO collaborators he finished a paper on long-duration flare events. They found an excellent match to the Neupert effect (hard X-rays proportional to derivative of soft X-rays) for these events as well as for the usual, more impulsive, compact flares. As well, he worked on software for access to broad-band spectral data from HXT, SXS, and SXT. At the Hawaii CDAW Wuelser presented combined Mees/Yohkoh observations of the early phases of the two workshop flares, and discussed them in the context of the chromospheric evaporation model. Wuelser wrote a manu- script on the early phase of the 1991 November 15 flare. He led the UH effort to blunt the negative impacts of the failure of the SXT aspect telescope on the co-registration of the Mees and Yohkoh data. Mees engineers M. Waterson and E. Kiernan installed a small full-sun white light telescope and CCD camera on the Mees spar. The digital white-light images are now regularly stored with the MCCD H-alpha data, and serve to determine the absolute coordinates of all Mees partial-sun observations. Wuelser evaluated the system and found it to be accurate to about 5". Mickey installed several hardware upgrades in the IVM. Mechanical shutters, replacing the liquid-crystal shutters, appear to have more than adequate timing consistency, and have resulted in a significant improve- ment in operating cadence due to better transmission and operational differences. The first of two planned optics enhancements has been installed and performs as expected, eliminating the astigmatism previously seen in the data images. A minor modification to the helium distribution system appears to have reduced the Fabry-Perot drift to the point where sequences of observations over spans of hours can be considered. Mickey and Metcalf began analysis of the H-alpha linear polarization data for flares observed by Mees and Yohkoh. Metcalf finished analyzing data from AR6952 and worked on a manuscript. He finds no compelling correlation between sites of high photospheric vertical electric current density (Mees data) and sites of soft x-rays (observed by Yohkoh). Jiao and Metcalf worked on the height dependence of the chromospheric magnetic field using Na-D data. We have successfully obtained an initial measure of the Lorentz force as a function of height in the atmosphere. Interestingly, the force appears to increase with height throughout the upper photosphere and low chromosphere. Finally, he provided a magnetogram to G. Doschek for his paper on the 1992 January 5 flare. In November, Leka spent one month at ISAS. She worked both with colleagues from Japan (Bachtiar, Nitta, Shibata, Kurokawa) and others who were visiting Japan (von Driel). Leka talked about the IVM with various audiences at ISAS, NAOJ and Hida Observatory, and helped with the interpretation of UH magnetogram data, both from this instrument and the Stokes Polarimeter. She also worked on integrating SXT images into the study of emerging flux in NOAA AR7260 (August, 1992), and which will comprise a portion of her PhD thesis. PLANS FOR JANUARY AND FEBRUARY Hudson will continue his work on accelerated particles and their effects as shown in the impulsive footpoints, analysis of the expansion of active-region loops and its contribution to the slow-speed component of the solar wind, and active region evolution. He will attend and present papers at the Yohkoh science workshops in January and February. He will submit a short paper entitled "Particle Acceleration in the SXT context" as part of the proceedings for a Japanese symposium that took place last September. He will begin new research with T. Sakao on defining conjugacy in complex flares, starting with the Feb. 6 LDE and with Y. Uchida and J. Khan on flare phenomena seen in the distant corona on inadvertently heavily-overexposed SXT images. Wuelser will continue the analysis of the flares of 1991 October 24, and 1992 July 16. He will also work on open questions that were identified during the Hawaii workshop in November, in preparation for the Yohkoh meeting in February at ISAS. Finally, he will work on alternatives to the present Mees white light images for purposes of improved Mees/Yohkoh image co-registration. Mickey and Leka will install and test the replacement telescope secondary for the Imaging Vector Magnetograph, which is intended to correct residual spherical aberration in the optical system. Minor modifications to the software will be done in order to permit automated long sequences of magnetograms. Mickey and Metcalf will continue the H-alpha polarization analysis and begin the comparison with Yohkoh data, if appropriate. Metcalf plans to finish the AR6952 manuscript. He will continue to work with Jiao on the height dependence of the magnetic field using a combination of Na-D and FeI magnetograph data. They will study the extent to which the field is force-free and then attempt to use the Na data to resolve the 180 degree magnetic-field ambiguity. Finally, Metcalf will work on active region development around the time of the 1991 15 November flare for the February Yohkoh meeting. Leka will help with the optics upgrades for the IVM, and concentrate on both finishing the study of AR7260 and obtaining additional datasets on emerging flux regions on the Sun. She will submit a proposal for a special joint SXT/IVM observing campaign once the spatial resolution of the IVM is improved by the new telescope secondary. Canfield will visit ISAS for one month in January and February, working on Yohkoh and Mees data for co-observed flares. With Acton, he plans to work on a manuscript on the preflare H-alpha and X-ray motions and brightenings associated with the 1991 November 15 and October 24 flares. He also plans to work on a paper on the dynamics of the 1991 November flare. -------------------------------------------------------------------------------- UNIVERSITY OF CALIFORNIA AT BERKELEY MAJOR ACTIVITIES FOR THE MONTHS OF NOVEMBER AND DECEMBER The work during this reporting period (Nov-Dec, 1992) consisted of data analysis and interpretation, preparation and presentation of papers, and software development. McTiernan participated in the Workshop on the Oct. 24, 1991 and Nov. 15, 1991 flares held at the University of Hawaii from November 3-5, and presented results from the multispacecraft observations of the hard X-ray spectra for the Nov. 15, 1991 event, and also measurements of temperature and density for both events. Work on the the paper by Kane and Mctiernan concerning the 2-NOV-91 and 15-NOV-91 flares, using the multi-spacecraft data (Yohkoh SXT, HXT and WBS, GOES, Ulysses and PVO) is continuing. McTiernan presented a paper on the temperature and density structure of flares, based on the analysis of 27 flares observed by Yohkoh from Oct. 1991 to Jan. 1992, at the American Geophysical Union (AGU) meeting held in San Francisco from Dec. 7 to 11, 1992. A paper suitable for publication in Ap. J. is expected to be completed during the next reporting period. Mctiernan is also working on the comparison of thick-target electron beam models with HXT results. HXT spectra are now available to allow for a comparison of the observed spectra as functions of distance from the acceleration region to those calculated using simple thick target loop models. Terry Slocum, a student at UCB, has completed a program for producing survey plots of the WBS data. He is currently studying gradual hard X-ray sources observed by the Yohkoh WBS and HXT. -------------------------------------------------------------------------------- STANFORD UNIVERSITY (DR. P. STURROCK) MAJOR ACTIVITIES FOR THE MONTHS OF NOVEMBER AND DECEMBER Our Yohkoh-related activities during the past two months were as follows. Peter Sturrock attended the workshop on major flares observed by Yohkoh that was held in Hawaii during the first week of November. Klimchuk visited ISAS between November 7 and 25, where he analyzed SXT data as part of his study of coronal mass ejections (CMEs). In particular, he carefully examined the SFD optical disk movie for evidence of eruptive events that occurred during the times when the Mark III coronagraph at HAO's Mauna Loa Solar Observatory (MLSO) was operating. He identified 29 such events, with lateral sizes ranging from about 15 - 60 degrees in position angle and radial velocities ranging from about 20 - 200 km/s. Klimchuk has been in close contact with David Sime, his collaborator on this study at HAO. Klimchuk has submitted to Sime a prioritized list of the 29 events, and has requested permission to visit HAO to examine the MLSO data on these events (this request was made both through Sime and, more formally, through the HAO Visitor Committee.) In addition, Klimchuk has requested a list of CME events seen by MLSO during the Yohkoh period. He has been waiting for this list for several months, but apparently HAO has been short of manpower to search the data and generate the list. Once permission is granted, Klimchuk intends to visit HAO to examine the MLSO data for the 29 soft X-ray events. Also, he will examine the SXT data for the MLSO CME events once the event list is provided. -------------------------------------------------------------------------------- SOLAR PHYSICS RESEARCH CORPORATION (KAREN L. HARVEY) MAJOR ACTIVITIES FOR THE MONTHS OF NOVEMBER AND DECEMBER Activity these last two months has focussed on several areas: (1) Continued Compilation of a bibliography of SXT/Yohkoh papers published. The SXT bibliography consists of three lists: (1) papers published in referred journals, (2) papers presented at scientific meetings (listed by meeting) and (3) papers published in general science publications. In addition to maintaining the bibliography on solara.tuc.noao.edu in Tucson, it also resides on sxt3 in /usr/people/harvey/sxt.bibliography, and is more generally available on the Lockheed and ISAS computers in: /ys/gen/doc/papers.published, /ys/gen/doc/papers.meetings, /ys/gen/doc/papers.popular. This lists will be updated periodically. (2) Successful collaborative observing program between Yohkoh SXT instrument and the NSO/KP magnetograph. Objective of this effort is to obtain high temporal and spatial resolution PFI observations of Bright Points to determine the scale of BP intensity and structural variations. Requested were 2 x 2 full-resolution map, 5x5 arcmin area, a time resolution of 32 seconds, and maximum exposure of 5 seconds. Coordinated magnetic field observations were to be taken by NSO/KP spectromagnetograph. Simultaneous observations were obtained by Yohkoh SXT instrument and the NSO/KP magnetograph on December 9 and 10, 1992. The best set observations were acquired on December 9, with several bright points in the field of view and clear weather at Kitt Peak. The weather at Kitt Peak was mainly cloudy on December 10, but a few magnetograms were obtained through the day, sufficient to watch the evolution of the quiet sun fields. A preliminary analysis of these data will be presented at a Yohkoh meeting at ISAS late February 1993. It also is hoped that similar collaborative observations can be made in the near future. (3) Continued Discussions with Keith Strong on next phase of study of BPs. This includes the development of a detailed plan of research using current data to sample during the more than one year of operation of Yohkoh. We are considering the specific properties and methods of analysis of the data to determine time variation in the counts of BPs, their association with magnetic fields and He I 10830 dark points, lifetimes, temperatures, temporal variations, solar rotation rates. (4) Supplying for the availability on the ISAS computers NSO/KP magnetograms and He I spectroheliograms for the September - November 1991 period and the April-May 1992 period. These data were missing from the archives and have now been filled in for general use. He I 10830 spectroheliograms of several filament eruption events seen by Yohkoh have been provided to Alan McAllister for a collaborative study of the SXT data and the corresponding two-ribbon events and coronal hole changes seen in the He I data. Page ?? -------------------------------------------------------------------------------- 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 | January 10, 1993 December 1992 |-------------------------------- | 6. PERFORMING ORGANIZATION | CODE: O/91-30 -----------------------------------------------|-------------------------------- 7. AUTHOR(S) | 8. PERFORMING ORGANIZA- M. D. Morrison | 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 December 1992 |-------------------------------- |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 | ?? | ------------------------|------------------------|-----------------|------------ For sale by: Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402-0001 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ No. Delivered From Subject Lines 4 Dec 23 13:33 POSTMAN [From: >> Monday, Jan 11, 1993 1:17 PM PST ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~