Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-37334) (for the month of May, 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 >> Yohkoh did an off-pointing experiment for 3 orbits on 8 May to record the x-ray corona out as far as we could with 15 second exposures. The composite picture is really quite lovely, stretching over 72 arcminutes from east to west. The corona is visible out to 1 solar radius. The pictures were acquired from about 0300 to 0600 UT on 8 May. Great discoveries proliferate daily. Hudson and Acton found that the umbra of the small sunspot which was the site of the action of the 15 November 1991 X-flare actually moved about 3 arcsec north during the 8 minutes of the impulsive flare activity. This corresponds to a motion of 4+ km/sec. It may recalled that this was a white light flare. Hugh Hudson measured the peak intensity of the brightest kernel at 30% brighter than the 4310 A photosphere. New scientific insights: One of the most interesting recent developments is the strong possibility that there might be only two fundamental kinds of filament disappearance events. In one kind, long discussed and interpreted by the so-called Kopp & Pneuman model, the eruption breaks through the overlying coronal fields and a large arcade of "McDonald's arches" appear in x-rays. In the other kind the erupting filament doesn't manage to break out, the soft x-ray emission is intense over an extensive area, and x-ray loops appear along as well as across the magnetic neutral line. << Collaborating Observations >> On 12-May, Marilym Bruner of Lockheed Palo Alto Research Laboratory had a successful launch of her SPDE rocket. The Dual Range Spectrograph (DRSG) instrument recorded a very good set of spectra images on the UV side, and a rather limited spectra on the EUV side. The UV side caught C-IV on one end of the spectra, and missed Lyman-alpha off the end on the other end. There was a complete set of spectra captured in between these limits. The EUV side captured He-304, but, at first look, the remainder of the EUV lines were overwhelmed with scattered light. The first DRSG spectra were recorded with the slit in N-S direction, and Page 2 passed slightly east of the trailer spot of the AR7154 as shown by the slit-jaw image. The second DRSG spectra were taken with the slit passing through the umbra of the AR7154 trailer spot. The third spectra were not recorded as the camera was out of film due to some operations anomalies during prelaunch testing. The leader spot of the AR was not visible in H-alpha, but is visible in the slit-jaw image. The Normal Incidence X-ray Imager Experiment (NIXIE) was apparently not successful. All of the film images have excessive light on them. The reasons are not clear. The problem will be investigated upon return to Palo Alto. The Soup/OSL Lockheed team is now set up on LaPalma with the tunable filter system. They do their best to observe the same regions as SXT has chosen and plan to continue their campaign until July. Of course, Mees Solar Observatory continues to devote their work to Yohkoh joint observing and the Imaging Vector Magnetograph is now coming on-line. Hiraiso Observatory is taking digital high resolution H-alpha of superb quality on the Yohkoh Observing region and Norikura and Hida observatories jointly observe whenever the weather permits. << Data Analysis Software >> Software was written to support the launch of the Lockheed UV rocket on May 12. Routines were developed to allow duty scientists at ISAS to process and write selected SXT X-Ray and Optical image files to disk. Since the primary data transfer mode from ISAS to White Sands Missle Range (WSMR) was via modem, there were some corresponding constraints placed on the transferred data files. Other routines were developed to aid in the transfer of the image files and to read in and display a selected image or sequence of images at White Sands. It is expected that most of the routines are general enough to make them applicable to future collaborative efforts. Jim Lemen and Greg Slater wrote routines to extract all images from multiple SFD (SXT processed, composite image) and write them to the Panasonic optical disk. We have now recorded about 2000 frames covering the period from early November, 1991 to late March, 1992 (gaps need to be filled in). The quality of the images recorded on the Panasonic optical disk is much poorer than the quality of the Sony images, but they still provide a useful database. In addition to the images, a frame directory was written at that same time. IDL software will be written to access this index and command the Panasonic to display a particular frame or series of frames. A mechanism was put in place to allow access to multiple host machines for the Yohkoh software at a single site. The primary motivation for this was that the primary Yohkoh software server at isas was scheduled for system maintenance and was thus expected to be offline for a couple of days. Since the software residing on that machine is currently accessed by approximately 16 other work stations, it was appropriate to provide backup capabilities so that data base access and analysis could continue when that machine is offline (whether Page 3 planned or unplanned). The backup system will also provide data reformatting and tape distribution functions if that is required (extended down-time). This system is automated in the sense that the primary host function is checked when the user logs onto his/her local work station. If the primary host is not responding, the backup Yohkoh software host is selected and used for the remainder of that session. More than one backup host may be defined at one site and this backup capability could be installed at any yohkoh software site. << Instrument Operations and Health >> No SEU-induced disruptions in SXT operations were experienced during the entire month of May. We are currently building on a new record for the largest number of consecutive exposures without an SEU caused gap in operations since launch. Coupled with the almost flawless performance in this area during the preceding month, this provides strong evidence that the automatic SEU recovery code installed in late March is having beneficial effect. One consequence of this is that the period between late March and June should provide the longest period of uninterrupted cadence in the SXT full disk movie sequences to date. << Instrument Calibration >> The CCD gain was determined from calibrations that were run last October and 2 weeks ago. The Data Number conversion factor was discovered to be close to 90 electrons/Data Number for both cases. This is about 10% lower that the pre-launch value of 100 e/DN and should be used for absolute flux derivations until further notice. << Data Flow >> The catchup reformatting has gone extremely well. On 9-Jun, all Yohkoh data between 29-Sep and 30-May had been reformatted and distribution tapes had been made. The last few weeks of catchup for Nov-91 and Jan-92 data was finished. It will be necessary to re-reformat some of the data since the reformatting software has been modified a few months ago, but this process can be done at a lower priority. It will also be extremely easy to continue to stay current and distribute the new Yohkoh data as it takes less than two days to reformat one week of data. In late May, a recommendation was presented to Prof. Ogawara of ISAS to purchase (3) Tahiti MO disk drives to run on a Sun workstation. The Yohkoh team also request (100) high capacity disk platters. Tahiti high capacity platters can accommodate 930 megabytes as compared to the 594 that the Richo disks can hold. These platters will only be able to be used in the Tahiti drives. A Tahiti drive and Richo drive can sit on the same Sun so disk to disk copies can be made without using the network for the J-side members who use Richo drives at their institutions. Page 4 LPARL Production tape copying and distribution continues. Twenty-four weekly tapes have had all copies made (except NSSDC). Nineteen of these have been distributed. Current backlog at LPARL at the time of this writing (1 tape) will be eliminated by the time Mons Morrison returns from ISAS with the next batch. << Problems >> Whatever is outgassing to contaminate the SXT optical system hasn't finished yet. The aspect signal continues to decrease although the curve is flattening out. As of 9 May we'd lost 11% of the signal we recorded on 1-April. Some kind of volatile contamination on the CCD disappeared during the warm up on 8 April. Now, a month later it is beginning to appear again. We are planning another 1-day warmup next week. << Papers and Conferences >> It has been a fruitful month, about 30 refereed papers have submitted for publication. Here is the list: Submitted to SCIENCE 1. L.Acton, S.Tsuneta, Y.Ogawara, R.Bentley, M.Bruner, R.Canfield, L.Culhane G.Doschek, E.Hiei, T.Hirayama, H.Hudson, T.Kosugi, J.Lang, J.Lemen J.Nishimura, K.Makishima, Y.Uchida The Yohkoh Mission for High Energy Solar Physics Submitted to Publications of the Astronomical Society of Japan 2. G.Kawai, H.Kurokawa, S.Tsuneta, T.Shimizu, K.Shibata, L.Acton, K.Strong, N.Nitta Comparison between H-alpha and Yohkoh Soft X-ray Images of Emerging Flux Regions 3. G.A.Doschek, J.T.Mariska, T.Watanabe, E.Hiei, J.Lang, J.L.Culhane, R.D.Bentley, C.M.Brown, U.Feldman, A.T.Phillips, K.J.H.Phillips, A.C.Sterling Yohkoh Bragg Crystal Spectrometer Observations of the Dynamics and Temperature Behavior of a Soft X-ray Flare 4. J.Lang, R.D.Bentley, C.M.Brown, J.L.Culhane, G.A.Doschek, T.Watanabe, E.Hiei, R.D.Deslattes, A.Fludra, P.R.Guttridge, J.E.Magraw, J.Payne, C.D.Pike, M.W.Trow The Performance of the Yohkoh Bragg Crystal Spectrometer 5. J.L.Culhane, A.Fludra, R.D.Bentley, G.A.Doschek, T.Watanabe, E.Hiei, J.Lang, M.K.Carter, J.T.Mariska, A.T.Phillips, K.J.H.Phillips, C.D.Pike, A.C.Sterling Observations of Several Small Flares with the Bragg Crystal Spectrometer on Yohkoh Page 5 6. Tetsuya Watanabe, E.Hiei, J.Lang, J.L.Culhane, R.D.Bentley, G.A.Doschek, B.J.I.Bromage, C.M.Brown, U.Feldman, A.Fludra, T.Kato, J.Payne Helium-Like Sulphur Emission Lines in Solar Active Regions and Their Sub-C Class Variability 7. H.Kurokawa, G.Kawai, T.Kitahara, R.Kitai, Y.Funakoshi, Y.Nakai, S.Tsuneta, T.Kosugi, S.Enome, L.Acton, Y.Ogawara Detailed Comparison between H-alpha and Yohkoh Soft X-ray Images of a Confined Two-Ribbon Flare 8. T.Shimizu, S.Tsuneta, L.W.Acton, J.R.Lemen, Y.Uchida, et al.* Transient Brightenings in Active Regions Observed by the Soft X-ray Telescope on Yohkoh (*: names should be explicitly given) 9. K.Ichimoto, T.Hirayama, A.Yamaguchi, K.Kumagai, S.Tsuneta, H.Hara, L.Acton, M.Bruner The Effective Geometrical Thickness and Electron Density of a Flare of Dec.2, 1991 Observed with the Soft X-ray Telescope of Yohkoh and Coronagraph 10. T.Sakurai, K.Shibata, K.Ichimoto, S.Tsuneta, L.W.Acton Flare-Related Relaxation of Magnetic Shear as Observed with the Soft X-ray Telescope of Yohkoh and with Vector Magnetographs 11. S.Tsuneta, T.Takahashi, L.Acton, M.Bruner, K.Harvey, Y.Ogawara Global Restructuring of the Coronal Magnetic Fields Observed with Yohkoh Soft X-ray Telescope 12. S.Tsuneta, H.Hara, T.Shimizu, L.Acton, K.Strong, H.Hudson Yohkoh X-ray Observation of a Large Loop Flare at the Limb 13. L.W.Acton, U.Feldman, M.E.Bruner, G.A.Doschek, T.Hirayama, H.S.Hudson, J.R.Lemen, Y.Ogawara, K.T.Strong, S.Tsuneta The Morphology of 20 x 10^6 K Plasma in Large Solar Flares 14. K.Strong, K.Harvey, T.Hirayama, N.Nitta, T.Shimizu, S.Tsuneta Observations of the Variability of Coronal Bright Points by the Soft X-ray Telescope on Yohkoh 15. H.Hudson, L.Acton, T.Hirayama, Y.Uchida White-Light Flares Observed by Yohkoh 16. R.C.Canfield, H.S.Hudson, K.D.Leka, D.L.Mickey, T.R.Metcalf, J.-P.Wuelser, L.W.Acton, K.T.Strong, T.Kosugi, T.Sakao, S.Tsuneta, J.L.Culhane, A.Phillips, A.Fludra The X Flare of 15 November, 1991: Coordinated Mees/Yohkoh Observations 17. J.A.Klimchuk, J.R.Lemen, U.Feldman, S.Tsuneta, Y.Uchida Thickness Variations along Coronal Loops Observed by the Soft X-ray Telescope on Yohkoh 18. P.C.H.Martens, D.O.Gomez Spatial Power-Spectra from Yohkoh Soft X-ray Images Page 6 19. T.Kosugi, T.Sakao, S.Masuda, K.Makishima, M.Inda, T.Murakami, Y.Ogawara, K.Yaji, K.Matsushita The Hard X-ray Telescope (HXT) on Board Yohkoh: Its Performance and Some Initial Results 20. M.Yoshimori, Y.Takai, K.Morimoto, K.Ohki Characteristics of Two Gamma-Ray Flares Observed with the Wide Band Spectrometer aboard Yohkoh 21. M.Yoshimori, Y.Takai, K.Morimoto, K.Ohki, T.Watanabe, I.Kondo, J.Nishimura The Yohkoh Wide Band Spectrometer: Performance and Initial Results 22. T.Sakao, T.Kosugi, S.Masuda, M.Inda, K.Makishima, R.C.Canfield, H.S.Hudson, T.R.Metcalf, J.-P.Wuelser, L.W.Acton, Y.Ogawara Hard X-ray Imaging Observations by Yohkoh of the 15 November, 1991 Solar Flare 23. K.Matsushita, S.Masuda, T.Kosugi, M.Inda, K.Yaji The Average Height of Hard X-ray Sources in Solar Flares 24. Takashi Watanabe, Y.Kozuka, M.Ohyama, M.Kojima, K.Yamaguchi, S.Watari, S.Tsuneta, J.A.Joselyn, K.L.Harvey, L.W.Acton, J.A.Klimchuk Coronal/Interplanetary Disturbances Associated with Disappearing Solar Filaments 25. K.Shibata, Y.Ishido, L.Acton, K.Strong, T.Hirayama, Y.Uchida, A.McAllister, R.Matsumoto, S.Tsuneta, T.Shimizu, H.Hara, T.Sakurai, K.Ichimoto, Y.Nishino, Y.Ogawara Observations of X-ray Jets with the Yohkoh Soft X-ray Telescope 26. H.Hara, S.Tsuneta, J.R.Lemen, L.W.Acton, J.M.McTiernan High Temperature Plasmas in Active Regions Observed with the Soft X-ray Telescope aboard Yohkoh 27. N.Nitta, T.S.Bastian, M.J.Aschwanden, K.L.Harvey, K.T.Strong Simultaneous Observations of Coronal Bright Points in X-ray and Radio Wavelengths 28. Y.Uchida, A.McAllister, K.Strong, Y.Ogawara, T.Shimizu, R.Matsumoto, H.Hudson The Continual Expansion of Active Region Corona Observed by the Yohkoh Soft X-ray Telescope Page 7 29. A.McAllister, Y.Uchida, S.Tsuneta, K.Strong, L.Acton, E.Hiei, M.Bruner, Takashi Watanabe, K.Shibata Internal Structure of Coronal Soft X-ray Source Appearing in Association with the Dark Filament Disappearance of September 28, 1991 by Yohkoh Soft X-ray Telescope 30. Y.Ogawara, Y.Uchida, H.Hudson The Yohkoh Satellite: Status and Initial Results This submission of papers signals the completion of the initial phase of data analysis and the opening up of opportunity for broader participation in research and publication with Yohkoh data. There will also be a good representation of Yohkoh results at the AAS meeting in Columbus, OH, this week. << Bibliography >> The following is a bibliography of papers on the SXT instrument and data published in refereed journals and in Meeting Proceedings. This list currently is being compiled and at this time is not yet complete. Papers are listed by title, author, and the reference (in the new style format recently accepted as the standard by scientific journals). In order to compile and maintain a complete list of SXT papers, we are asking the members of the SXT Team to forward any and all papers that (1) have been published, (2) have been submitted for publication, (3) have been presented at a scientific meeting, or (4) have been published as a popular article. Separate lists will be maintained of (a) published papers, (b) papers presented at meetings (these papers will be listed by the meeting), and (c) popular articles. Please send this information to Karen L. Harvey (kharvey@noao.edu) The last additions to this list was on May 20, 1992. "The Solar-A Soft X-ray Telescope Experiment": Acton, L., Bruner, M., Brown, W., Lemen, J., Hirayama, T., Tsuneta, S., Watanabe, T., and Ogawara, Y., Adv. Space Res., 8, No. 11, 93 (1988). "Capabilities and Limitations of Solar-A": Acton, L. W. and Hudson, H. S., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 28-36 (1991). "A New Model For the Formation of Solar Prominences": Antiochos, S. K. and Klimchuk, J. A. ApJ 378, 372-377 (1991). "Directionality of Continuum Gamma Rays from Solar Flares": Bai, T., ApJ 334, 1049 (1988). "Classification of Solar Flares": Bai, T. and Sturrock, P. A., ARAA 27, 421 (1989). Page 8 "A 154-Day Periodicity in the Occurrence Rate of Proton Flares": Bai, T. and Cliver, W., ApJ 363, 299 (1990). "A 154-Day Periodicity in the Occurrence Rate of Flares for Solar Cycle 19 through 21": Bai, T., Cliver, E. W., and Kile, J. N., in Proc. 21st International Cosmic Ray Conference (Adelaide), 5, 20 (1990). "Methods of Periodicity Analysis: Relationship between the Rayleigh Analysis and a Maximum Likelihood Method": Bai, T., 1992, ApJ 397, in press (1992) "The 154-Day and Related Periodicities and an Oblique Rotator in the Sun": Bai, T. and Sutrrock, P. A. (1992), in preparation, "Simulation of SXT Response to XSST Soft X-Ray Spectrum": Brown, W. A., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 193-196 (1991). "The Soft X-Ray Telescope for the Solar-A Mission": Bruner, M. E., Acton, L. W., Brown, W. A., Stern, R. A., Hirayama, T., Tsuneta, S., Watanabe, T., and Ogawara, Y., in `Proceedings of the 1988 Yosemite Conference on Outstanding Problems in Solar System Plasma Physics: Theory and Instrumentation', J.H. Waite, J.L. Birch and R.L. Moore (eds), Am. Geophysical Union Monograph 54, pp. 187-197 (1989). "Moisture Induced Dimensional Changes in Hydrophobic Graphite-Resin Laminates": Bruner, M. E., Bahnsen, E. B., Cruz, T., Hong, L., and Jurcevich, B., SPIE Vol. 1335 Dimensional Stability, pp. 92-95 (1990). "Magnetic Morphology of Nonthermal Electron Precipitation During Three Flares in a Highly Nonpotential Active Region": Canfield, R. C., Leka, K. D., and Wulser, J.-P., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 96-99, 1991. "X-ray Calibration of a Virtual Phase 1024 x 1024 CCD": Catura, R. C., Lemen, J. R., Morrison, M. D., Windt, D. L., Jordan, W. C., and Acton, L. W., SPIE Vol. 1159 `EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy and Atomic Physics', pp. 578-586 (1989). "Simulated SXT Observations of Coronal Loops": Dixon, W. W., Klimchuk, J. A., Sturrock, P. A., Lemen, J. R. in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 297-301 (1991). "Spectra of MHD Turbulence in the Solar Corona": Gomez, D.O. and Martens, P.C.H., Mem. d. Soc. Astron. It., in press (1992). Page 9 "Microflares Observed in He I 10830 and Their Relation to the Quiet Sun Magnetic Fields": Harvey, K. L., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 62-66, 1991. "Use of Graphite Epoxy Composites in the Solar-A Soft X-Ray Telescope,": Jurcevich, B. K. and Bruner, M. E., `Advances in Optical Structure Systems', SPIE, vol. 1303 (1990). "Coronal Magnetic Fields Produced by Photospheric Shear": Klimchuk, J. A., Sturrock, P. A., and Yang, W.-H. ApJ 335, 456-467 (1988). "Magnetic Properties of CIV Doppler Shift Patterns": Klimchuk, J. A., Solar Phys. 119, 19-34 (1989). "Force-Free Magnetic Fields: Is There a `Loss of Equilibrium'?": Klimchuk, J. A. and Sturrock, P. A. ApJ, 345, 1034-1041 (1989). "Shear-Induced Inflation of Coronal Magnetic Fields": Klimchuk, J. A., Ap. J., 354, 745-754 (1990). "The Practical Application of the Magnetic Virial Theorem": Klimchuk, J. A., Canfield, R. C., and Rhoads, J. E., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 219-223 (1991). "The Practical Application of the Magnetic Virial Theorem": Klimchuk, J. A., Canfield, R. C., and Rhoads, J. E. ApJ 385, 327 (1992). "Three-Dimensional Force-Free Magnetic Fields and Flare Energy Buildup": Klimchuk, J. A., and Sturrock, P. A., ApJ 385, 344-353 (1992). "The Practical Application of the Magnetic Virial Theorem": Klimchuk, J. A, Canfield, R. C., and Rhoads, J. E., ApJ 385, 327-343 (1992). "Measurement of the Point Spread Function and Effective Area of the Solar-A Soft X-ray Telescope Mirror": Lemen, J. R., Claflin, E. S., Brown, W. A., Bruner, M. E., Catura, R. C., and Morrison, M. D., SPIE vol. 1160 `X-Ray/EUV Optics for Astronomy and Microscopy', pp. 316-322 (1989). "Imaging Capabilities of SXT for Solar-A": Lemen, J. R., Acton, L. W., Brown, W. A., Bruner, M. E., Catura, R. C., Strong, K. T., and Watanabe, T., Adv. Space Res. (1991). "SXT Observations of MHD Turbulence in Active Regions": Martens, P. C. H., Gomez, D. O., Slater, G., and Golub, L., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 291-296 (1991). 1992 ``Can Yohkoh/SXT Observe Coronal MHD Turbulence?": Martens, P. C. H. and Gomez, D. O., Mem. d. Soc. Astron. It., in press (1992). "SOLAR-A Reformatted Data Files and Observing Log": Morrison, M. D., Lemen, J. R., Acton, L. W., Bentley, R. D., Kosugi, T., Tsuneta, S., Ogawara, Y., Watanabe, T., Solar Phys. 136, 105, 1991. "The SOLAR-A Mission: An Overview": Ogawara, Y., Takano, T., Kato T., Kosugi, T., Tsuneta, S., Watanabe, T. Kondo, I., Uchida, Y., Solar Phys. 136, 1, 1991. Page 10 "Cylindrically Symmetric Force-Free Magnetic Fields": Porter, L. J., Klimchuk, J. A., and Sturrock, P. A., ApJ 385, 738-745 (1992). "Helioseismology Observations by the Solar-A Satellite": Sakurai, T., in `Progress of Seismology of the Sun and Stars', Y. Osaki and H. Shibahashi (eds.), Lecture Notes in Physics, No. 367, Springer-Verlag, pp. 253-256 (1990). "Plasma Diagnostic Capabilities of the Soft X-ray Telescope on Solar-A": Strong, K. T., Acton, L. W., Brown, W. A., Claflin, S. L., Lemen, J. R., and Tsuneta, S., COSPAR 1990, to be published in Adv. in Space Res. (1990) "Episodic Coronal Heating": Sturrock, P. A., Dixon, W. W., Klimchuk, J. A., and Antiochos, S. K., ApJ, 356, L31-S34 (1990). "Maximum Energy of Semi-Infinite Magnetic Field Configurations": Sturrock, P. A., ApJ 380, 655-659 (1990). "The Maximum Energy of Semi-Infinite Magnetic-Field Configuration": Sturrock, P. A., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 224-227, 1991. "The Emerging Picture of Solar Flares": Sturrock, P. A., `Comments in Astrophysics', in press (1992). "Search for Evidence of a Clock Related to the Solar 154-Day Complex of Periodicities": Sturrock, P.A. and Bai, T., ApJ, in press (1992). "Soft X-ray Telescope (SXT)": Tsuneta, S. and Acton, L.W., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 18-19 (1991). "The Electron Distribution and SXT Images of a Coronal Soft X-Ray Source": McTiernan, J. M., Kane, S. R., and Loran, J. M., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 179-183, 1991. "Magnetic Structures in the Corona": Sakurai, T., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 245-258, 1991. "The Soft X-Ray Telescope for the SOLAR-A Mission": Tsuneta, S., Acton, L., Bruner, J., Lemen, J., Brown, W., Caravalho, R., Catura, R., Freeland, S., Jurcevich, B., Morrison, M., Ogawara, Y., Hirayama, T., Owens, J., Solar Phys. 136, 37, 1991. "On Mechanisms of Solar Flares -- Some Observational Tests by Using Solar-A": Uchida, Y. and Shibata, K., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 230-236, 1991. "Search for Transient Coronal Holes by Solar-A Soft X-ray Telescope": Watanabe, T. T., in `Flare Physics in Solar Activity Maximum 22', Y. Uchida, R.C. Canfield, T. Watanabe, and E. Hiei (eds.), Lecture Notes in Physics, No. 387, Springer-Verlag, pp. 353-258, 1991. Page 11 << Personnel Travel >> The SXT team members who were at ISAS in May: ACTON 1-MAY-92 * 31-MAY-92 * 31 (total of 31 days) HUDSON 1-MAY-92 * 9-MAY-92 9 18-MAY-92 31-MAY-92 * 14 (total of 23 days) LINFORD 7-MAY-92 31-MAY-92 * 25 (total of 25 days) MORRISON 1-MAY-92 * 7-MAY-92 7 18-MAY-92 31-MAY-92 * 14 (total of 21 days) NITTA 1-MAY-92 * 31-MAY-92 * 31 (total of 31 days) METCALF 1-MAY-92 * 13-MAY-92 13 (total of 13 days) KANE 6-MAY-92 16-MAY-92 11 (total of 11 days) MCTIERNAN 6-MAY-92 21-MAY-92 16 (total of 16 days) The plans for SXT personnel at ISAS in June: ACTON 1-JUN-92 * 10-JUN-92 10 (total of 10 days) HUDSON 1-JUN-92 * 3-JUN-92 3 19-JUN-92 30-JUN-92 * 12 (total of 15 days) LEMEN 4-JUN-92 20-JUN-92 17 28-JUN-92 30-JUN-92 * 3 (total of 20 days) LINFORD 1-JUN-92 * 3-JUN-92 3 11-JUN-92 30-JUN-92 * 20 (total of 23 days) MORRISON 1-JUN-92 * 10-JUN-92 10 (total of 10 days) NITTA 1-JUN-92 * 6-JUN-92 6 21-JUN-92 30-JUN-92 * 10 (total of 16 days) MARTENS 4-JUN-92 30-JUN-92 * 27 (total of 27 days) NOTE: The "*" denotes travel which started before (or ended after) the dates listed. << Plans for June 1992 >> With activity levels way down, it was possible to define some new experiments to run when the peak x-ray brightness and large-flare probability is low. Jim Lemen will be setting up some tables to do deep exposures on faint things, and high time resolution observations of sparkling active regions. Respectfully submitted, Mons D. Morrison Frank Friedlaender Page 12 -------------------------------------------------------------------------------- UNIVERSITY OF HAWAII ACTIVITY REPORT (DR. R. CANFIELD) No input required for this month -------------------------------------------------------------------------------- UNIVERSITY OF CALIFORNIA AT BERKELEY No input required for this month -------------------------------------------------------------------------------- STANFORD UNIVERSITY (DR. P. STURROCK) No input required for this month -------------------------------------------------------------------------------- SOLAR PHYSICS RESEARCH CORPORATION (KAREN L. HARVEY) No input required for this month Page 13 -------------------------------------------------------------------------------- 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 | June 10, 1992 May 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 Jan, 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 | 13 | ------------------------|------------------------|-----------------|------------ For sale by: Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402-0001 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ No. Delivered From Subject Lines 2 Jun 1 9:32 POSTMAN [From: >> Wednesday, Jun 10, 1992 12:49 PM PDT