P009262 Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-37334) (for the month of December, 1991) 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 All operations and analysis activities continued with no problems. The team enjoyed a couple of weeks off for the holidays and a well deserved rest. As the holidays approached, the personnel stationed in Japan returned to the U.S. The SXT continues to provide wonderful x-ray images of the Sun. There have been over 118,000 partial frame images (PFI) taken, and over 23,000 full frame images (FFI) taken. The operational load continues to be quite significant for the scientists resident at ISAS, but it also provides the opportunity to speak to frequent visitors. The SXT operation was visited by Dr. B. C. Low this past week, and discussions were held about x-ray signatures for slow and fast shocks that may be observed by SXT. On 3 December 1991 Yohkoh observed an X2 flare. This was significant in that it was the first X-flare which was transmitted to a DSN station. It was the fourth flare to produce gamma rays (but only the 3rd while the telemetry was in high bit rate). On 4 December, the spacecraft was off-pointed over the East solar limb by 40 arc-min in order to allow SXT to make long exposures of the outer corona. Three X-ray exposures were made during a real-time KSC contact before the spacecraft was pointed to Sun-center. The X-ray images showed emission out to at least one solar diameter (which was the limit of the SXT field of view). These were the first such observations ever to be obtained at X-ray wavelengths. Plans for doing an extended survey around the entire Sun are being considered for some time next year. P009262 Page 2 There appears to have been a large flare on 20-Dec, but the holidays and the work to re-establish normal spacecraft operations has not allowed proper analysis of that data. The development of the data handling and analysis software has continued. The progress in this area is substantial, and the product is quite user friendly. This will make the use by future visiting scientists much easier. Since KSC commanding of the spacecraft was going to shut down over the new year, it was decided to not leave SXT in the observing mode. If a single event upset (SEU) occurred over the holiday, it could leave SXT in a dangerous state (leaving the shutter open with a thin x-ray filter will cause permanent damage to the CCD). As such, there are no SXT data from 28-Dec-91 18:40 UT to 4-Jan-92 11:20 UT. After many years of faithful service as Program Manager, Mike Finch has moved on to other responsibilities. Frank Friedlaender who had been the Program Controls and Subcontracts Manager has assumed the additional responsibilities of Program Manager. Frank will be assisted by Mons Morrison as Deputy Program Manager. We are looking forward to these additional responsibilities. << Data Analysis >> Second generation routines which will allow more flexibility in accessing the data are being developed. Programs already exist which allow the user to search over the whole mission to produce a list of images that satisfy a given criteria. These program have already been used to make a series of movies, one of which should have aired on NHK 1 in Japan (one of the educational TV stations) on new years day! << Data Flow >> As reported last month, the use of the DSN stations has increased the amount of data by at least a factor of two. This increase has allowed better coverage in the observations, but it has put new demands on the managing of the data. Since there can be up to a three day delay before the DSN data is available at ISAS, the reformatting process has to be modified. The current plan is to reformat the KSC data immediately upon receiving it at ISAS, and then reformat all data again after approximately three days. This final reformatted data will then be distributed to the co-investigators institutions. The current plan is to have a second sample data tape distributed by the end of January, and to have regular weekly data distribution starting by the beginning of February. The software to write the reformatted data and the analysis software to the tapes has been fully implemented and tested at a variety of sites. P009262 Page 3 The availability of the processed reduced spacecraft pointing information continues to be delayed. NEC of Japan has been working on the program which reduces the attitude instruments into absolute pointing coordinates, but progress has been slow. The new predictions is the program will be available in mid or latter January. This information is needed by the SXT team to allow the images to be registered to make movies. << Problems >> The decline in the transmission of the Aspect Sensor received more attention this month. A careful analysis of all data from mid-Sep to mid-Dec shows that the decay is exponential and that the predictions of the aspect telescope going blind in a few months might thankfully be off. Over the past 3 months, the transmission has decreased to about 50% of the original transmission. The decay is continuing and we are continuing to monitor the degradation. MSFC is looking into the possibility that the paint on the back side of the sun shield might outgas if it was not cured properly or if the temperature of the sun shield is higher than expected. There were a few SEUs (Single Event Upsets) in December. Normal recovery procedures were implemented and observations continued with minimum time down for most of them, but we were down for 2 days after an SEU on 21-Dec because it happened too late to implement the recovery procedure. There was also a filter soft error in latter December. It is possible that this error was due to an SEU also but the analysis of the data is still being performed. << Papers and Conferences >> The AGU meeting occurred in San Francisco on December 9-11. Dr. Loren Acton returned from ISAS in order to be here to present some of the results to date of the SXT data analysis. Professor Y. Ogawara, the Yohkoh Mission Manager from ISAS, also came for the AGU meeting. << Personnel Travel >> On 6-Dec Dr. Loren Acton returned from Japan. On 13-Dec Mr Mons Morrison returned from Japan for the holidays, and on 14-Dec Dr. Jim Lemen also returned from Japan. Dr. Hugh Hudson was the only U.S. representative to remain in Japan to assist in the operations of SXT. PROBLEMS AND SCHEDULE WORKAROUND/IMPACTS Other than the closure of some programmatic issues, there are no further problems and schedule workarounds. P009262 Page 4 PLANS FOR JANUARY 1992 1. Continue to complete the document package. 2. Continue the Data Analysis and Reduction software development effort. 3. Continue mission operations and data analysis at ISAS. 4. Future Personnel Travel - In the first week of January, Dr. Jim Lemen, Mr. Greg Slater, Dr. N. Nitta, and Dr. K. Strong will travel to Japan to assist in the operations of SXT and the analysis of the data available. Dr. Lemen will be there approximately 3 weeks, Mr. Slater for 6 weeks, Dr. Nitta for 2 months, and Dr. Strong for 3 months. In mid-Jan, Dr. Loren Acton will make a one week visit to Japan to establish observing sequences to try to establish to effectiveness of the CCD UV flood. Mr. Sam Freeland will also make a one week visit to test some modifications to the SXTE-U flight software to perform additional error checking and to test some analysis software packages at ISAS. Respectfully submitted, Mons D. Morrison Frank Friedlaender P009262 Page 5 -------------------------------------------------------------------------------- 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 observations, and software and hardware development. Hudson supported Yohkoh observations at ISAS. Canfield, Leka, Metcalf, and Wuelser supported Mees observation, in coordination with the Mees observers (Nitta, Judd, and Koon). Metcalf and Wuelser developed software so that the yohkoh duty scientist support function could be handled from Manoa, thereby enabling more effective data analysis. Metcalf revised the software that plots AR positions from the daily SEL region reports. All the UH scientists evaluated the standard SXT tables and a UH position paper was generated for Acton. Many coordinated Yohkoh/Mees observations were obtained. Most noteworthy is a dataset on an X-class white-light flare on November 15th. As well, observations of several interesting limb events were obtained with the new H-alpha video coronagraph. Hudson, Wuelser and Metcalf worked on Yohkoh/Mees co-alignment procedures, which now seem adequately understood and supported by high-8 or compressed narrow band or wide band images in the standard SXT table. Metcalf continued to work on the evolution of vector magnetograms and SXT images of AR6850, and Wuelser started work on the November 15th flare. Leka worked on defining a thesis related to Yohkoh and Mees vector magnetograms, and is converging toward a study of the current-carrying properties of emerging active regions. Chen learned how to read and display MCCD data and started working on some routine data analysis. Mickey, Weber and Waterson worked on IVM operational procedures and problems with the electronics. The sensor preamplifiers for the image stabilizer were almost completely rebuilt in an effort to eliminate a persistent 60Hz pickup. The active mirror was sent out for repair; in the meantime a temporary replacement has been installed. New blocking filters for both Halpha and 6301.5 been obtained. Waterson found and fixed a nasty ground loop problem which was causing problems with the Fabry-Perot controller. Mickey and Weber finalized and tested the retarder calibration routines, and Waterson fixed a problem in the retarder temperature control. The retarder settings now appear to be repeatable and stable. Mickey tested the overall polarization calibration of the instrument, and wrote routines to derive the Mueller matrix from a set of test data. The Mueller matrix looks good: the instrumental polarization and crosstalk terms are all quite small and the matrix appears to be stable. Weber cleaned up some of the operating software, adding better error handling capability and significantly reducing dead time during an observation sequence. Mickey replaced the liquid crystal shutters; the new ones have adequate contrast. P009262 Page 6 PLANS FOR JANUARY AND FEBRUARY Metcalf will continue on the AR6850 study. Wuelser will work on the Nov 15th flare. All will continue operational support at Mees and ISAS. Canfield will visit ISAS in February. Leka will converge on a thesis topic. Chen will work on MCCD data with Wuelser. Mickey will begin taking active-region polarization data with the IVM. Data reduction techniques will be tested and improved; quantitative instrumental calibration and noise characterization will be obtained. Mickey expects to beat down the last of the image stabilizer problems so that it will work as expected. -------------------------------------------------------------------------------- UNIVERSITY OF CALIFORNIA AT BERKELEY MAJOR ACTIVITIES FOR THE MONTHS OF NOVEMBER AND DECEMBER Two Yohkoh - related papers were presented by the UCB group at the Fall 1991 AGU meeting held from Dec. 9 to Dec. 13 in San Francisco. The first, by S. Kane, J. McTiernan and J. Loran, titled "Characteristics of Solar Flare X-ray Sources Observed with Yohkoh", was a description of SXT, HXT, and WBS observations of 3 large events in October and November, 1991. The second, by J. McTiernan and S. Kane, titled "Uncertainties in Yohkoh SXT Plasma Diagnostics", was an investigation of the calculation of temperatures and emission measures using SXT, with a small limb flare on 10/12/91 used as an example. This analysis is now contained in an SXT SXT Calibration Note, and the software used to do the calculation of temperature, emission measure, and the uncertainties will be available in the near future, once it is translated from Fortran into IDL. a light curve analysis program that will be included with the Yohkoh data analysis tools distribution. Also in December, J.McTiernan traveled to Japan to work on the software for WBS data analysis. The status of the UCB effort for spectral analysis is as follows: Spectral fitting software using forward-fitting techniques, and matrix inversion methods is complete. A light curve program, written by J. Loran is presently being tested and debugged and will be available in the near future. This program will include the above-mentioned spectral fitting routines, and is designed to be used with any solar data, not just WBS data. P009262 Page 7 -------------------------------------------------------------------------------- STANFORD UNIVERSITY (DR. P. STURROCK) MAJOR ACTIVITIES FOR THE MONTHS OF NOVEMBER AND DECEMBER During the past two months, we have begun to examine SXT data in earnest. Jim Klimchuk carefully searched all of the full frame images from week 40 for evidence of coronal mass ejections (CMEs) and any other interesting phenomena. He found three possible CME events, which is consistent with the rate of 0.5 events / day that is quoted by the coronagraph experts. To aid in this endeavor, Klimchuk wrote two IDL procedures (functions) called CME_SCAN.PRO and EXP_NORMAL.PRO. The first procedure calls the second and is used to homogenize the images in a data cube by: 1. decompressing the data; 2. subtracting a uniform background; 3. normalizing the exposure; and 4. recompressing the data. It is available for use by anyone who is interested. Klimchuk submitted two research topics to the Team Bulletin Board entitled "The Onset of Coronal Mass Ejections and Their Relationship to Solar Flares" (with Acton, Harvey, Marubashi, Sakurai, Sime, and Strong) and "Thickness Variations Along Coronal Loops" (with Lemen and Uchida). The others in the group have begun to think about additional research topics. At the present time, we only have data from week 40. We anxiously await additional data, which we plan to analyze aggressively when it becomes available! -------------------------------------------------------------------------------- SOLAR PHYSICS RESEARCH CORPORATION (KAREN L. HARVEY) MAJOR ACTIVITIES FOR THE MONTHS OF NOVEMBER AND DECEMBER Activity these last two months has revolved around a trip to LPARL in December to work with Keith Strong on Yohkoh SXT data and to attend the fall AGU meeting in San Francisco, December 9-11. During this visit, Keith and I developed a program to isolate and follow the light curves of x-ray bright points. We were successful in doing this for two bright points observed on November 21-22, 1991; one of the bright points was associated with an emerging magnetic bipole and the other a site of cancelling opposite polarities. The continuing study of x-ray bright points, their behavior, and their relation with the magnetic field was planned based on our progress during my visit to LPARL. One objective is to put together a paper for publication within the next few months. An abstract was drafted for submission for the COSPAR meeting next summer. P009262 Page 8 I also presented paper at the AGU during the Yohkoh session on the results of a study of dark points observed in He I 10830 spectroheliograms and their association with changes in the underlying magnetic field. In addition, some of the early results that compared x-ray bright points in the SXT images with the evolution of the photospheric magnetic field were presented. P009262 Page 9 -------------------------------------------------------------------------------- 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, 1992 December, 1991. |-------------------------------- | 6. PERFORMING ORGANIZATION | CODE: O/91-30 -----------------------------------------------|-------------------------------- 7. AUTHOR(S) | 8. PERFORMING ORGANIZA- M. D. Morrison | TION REPORT NO: P009262 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 - Jan. 10, '92 | For the month of Dec, 1991 |-------------------------------- |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 | 9 | ------------------------|------------------------|-----------------|------------ For sale by: Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402-0001 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Posted: Sat, Jan 11, 1992 12:39 AM PST Msg: EJJC-2988-7865 From: STSUNETA To: lacton, mfinch CC: jowens Subj: Thanks To: Mike Finch Fm: Saku Tsuneta CC: John Owens Date: Jan 11, 1992 Dear Mike, I heard that you leave the SXT team for a new project. I have been appreciating your contribution to SXT very much. I hope that you will also succeed in the new project. Thank you. Saku ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ No. Delivered From Subject Lines 3 Jan 6 22:22 POSTMAN [From: >> Monday, Jan 13, 1992 1:06 PM PST ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~