Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-40801) (for September 1996) 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 The transition into the new Fiscal Year should be easier since Congress did its job and there are no continuing resolutions or government shutdowns to manage. We are looking forward to exercising option 2 of the contract which allows us to continue operations for another year. We have printed some very nice small cards advertising Yohkoh which are now being distributed. << Solar Activity >> The main solar activity has been dominated by a large, decaying active region. During September the fourth rotation of 7978 took place. This old-cycle region remains surprisingly large both in horizontal and vertical extent, with a well defined streamer/arcade structure and a filament channel running through the middle. During the most recent passage the X-ray intensity has decreased and remains fairly constant. It appears to have finished with major flare activity, not surprising for an old-cycle region this late in the cycle. The global coronal structure changed profoundly with this region's appearance, and the coronal hemisphere containing the active region is still notably bright. SOHO has obtained many observations of the nice large-scale loops in this region. << Campaigns >> For three weeks during the month we continued to support the global Page 2 coronal campaign (Joint Observing Program 44, with SOHO). Sarah Gibson (GSFC) and Douglas Biesecker (Birmingham) are coordinating the campaign on the SOHO side. In Week 38 Yohkoh cooperated with SOHO observations of polar bright-point fluctuations, probably of interest in connection with coronal-hole boundary motions. During week 39 there began an extensive program of coordinated observations with ground-based observations at Tenerife. There will be additional SOHO-focused observations during October. In particular JOP033, which is being organized by Lyndsay Fletcher (Cambridge, Univ) will try to observe jets with Yohkoh/SXT and the CDS, SUMER, and EIT on SOHO. The SERTS rocket flight is currently planned for November 13, 1996 and the New Brunswick rocket may also fly during October or November. For Yohkoh operations, there is a text file accessible on the Web at http://www.space.lockheed.com/SXT/html2/First_Light.html which also lists the current SXT Chief Observer, or the unix command: # finger campaign@isass0.solar.isas.ac.jp | more The SOHO target planning is available from: http://sohowww.nascom.nasa.gov/operations/targets/today << Science >> This month we welcome David Alexander to the Lockheed Martin group. David, who was a Post-Doc at Montana State University for the past three years, will continue to spend the majority of his time on Yohkoh SXT and YPOP projects. During this month he continued to work on the 3-D loop generation software using the hydrodynamic model of S. Peres (Palermo) as the input for the solar plasma parameters (temperature and density as a function of position). David also began to do some preliminary work to analyze Yohkoh data from the time period of the Whole Sun Month SOHO JOP044. J. Lemen, S. Freeland and M. Larson (MSU) attended the CAN PI conference at NASA HQ as a part of the Yohkoh Public Outreach Project. They obtained ideas about how to present Yohkoh data to the public and how to make it more accessible for educational outreach. Tom Metcalf continues to work with George Fisher (UCB) and Dana Longcope (MSU) on the SOHO mini campaign data that compared soft X-ray and UV images of a small active region with photospheric vector magnetograms. The project's goal is to study transient brightenings. He has also been working on MEM and pixon HXT light curves for the 1992 January 13 limb flare. The next step is to put error bars on the HXT light curves. Tom is working with Don Mickey to improve the error analysis for H-alpha polarization observations made at Mees for a paper that will be resubmitted. Finally, Tom has improved the SXT version of the pixon code and is now testing it with pseudo data generated by David Alexander. There is a possibility of using this program to remove SXT Page 3 point spread function. Nariaki Nitta is using SXT 3-filter temperatures and HXT Low-band images to analyze superhot flares. The work has been resubmitted as a paper to ApJ. Future work will incorporate BCS Fe XXVI spectra. He plans to present results at the upcoming Yohkoh fifth year conference to be held in Yoyogi, Japan in November. Nariaki is also conducting a systematic study of microflares observed from AR 7260. And finally, he is working on two-sided jets with Mukul Kundu (University of Maryland). More careful analysis is needed to confirm that they do not produce type III bursts. Jean-Pierre Wuelser spent the month of September in Japan. He was the SXT chief observer for a week and a half. This was an interesting time as several campaigns took place during the period: a Bright Point campaign with SOHO, Mauna Loa, Kitt Peak, and Big Bear, an Active Region and Filaments campaign with the Canary Islands and SOHO, and some active region loop temperature observations with CDS, in which Andrzej Fludra, Joan Schmelz, and Jean-Pierre are interested. << 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 (http://www.space.lockheed.com/SXT/). We continue to 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. Sam Freeland updated and and made enhancements to the Web page. There is now IDL WWW movie making software that has added GIF animate support to supplement the mpeg formats. In addition, he added automatic WWW html table generation software to the Yohkoh/SXT operations pages. The WEB access statistics in September were 41903 accesses and 885 Mbytes transferred. Work continues on the fifth anniversary briefing package. The Yohkoh/ SXT business cards have been distributed and have been well received. << Yohkoh Operations and Health >> Yohkoh and the SXT continue to function very well. There has been no further increase in straylight since 25 August 1996. 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. Jean-Pierre Wuelser has revised the attitude software so that it can cope with changes in the HXA gain. The HXA (the HXT aspect sensor) experienced a gain change that was only recently noticed. The exact Page 4 cause of the decrease is not known, however, an evaluation of the performance has led to the conclusion that the decrease is caused by the HXA electronics, not the optics. The gain has been electronically increased, and so the problem has been eliminated for the time being. SXT experienced a normal level of Single Event Upset (SEU) events during the month: SXT seu 11-Sep-96 Pass 1: 960911-0929 recovered in pass 2 SXT write error 30-Sep-96 Pass 4: 960930-0724 recovered the next day. The problem is being investigated by H. Hara. Page 5 << Data Flow >> ------------------------------------------------------------------------------ Month Full Frame Images Observing Region Images Received Lost Received Lost Loss % QT FL Tot Thru Jun-94 223764 101082 956638 310812 1267450 495386 27.79 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 6937 3502 22177 3853 26030 13044 33.38 Nov-95 5745 2944 21252 517 21769 12119 35.76 Dec-95 6163 2615 24059 901 24960 11652 31.83 Jan-96 6474 2530 27015 1708 28723 14151 33.01 Feb-96 6200 2581 21380 890 22270 10773 32.60 Mar-96 6908 2869 25437 1460 26897 12274 31.33 Apr-96 7172 2124 45445 671 46116 18848 29.01 May-96 6925 2426 30272 1089 31361 12367 28.28 Jun-96 7522 2716 31984 1536 33520 14489 30.18 Jul-96 5954 1995 29886 4769 34655 12427 26.39 Aug-96 7214 3010 21187 1607 22794 9887 30.25 Sep-96 0 0 0 0 0 0 0.00 Total 399683 169926 1664682 372351 2037033 819198 28.68 Number of Full Frame Images Received: 399683 Number of Observing Region Images Received: 2037033 Total: 2436716 Approximate Number of Shutter Moves/CCD Readouts: 4255812 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 6 << 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 (%) 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 50.29 741.9 126452 7911 20.2 N/A Nov-95 50.11 735.1 122163 7814 25.2 / 2 20.3 N/A Dec-95 50.19 737.9 123705 7927 22.6 N/A Jan-96 50.81 761.3 136197 8888 21.5 N/A Feb-96 50.67 755.8 133263 8705 22.5 / 2 21.5 N/A Mar-96 50.85 762.9 136982 8973 20.3 N/A Apr-96 51.14 773.6 142250 9500 19.9 N/A May-96 51.16 774.4 140697 10018 19.1 N/A Jun-96 51.56 789.2 147705 10634 20.7 N/A Jul-96 57.45 1010.2 146293 12228 19.8 N/A Aug-96 52.58 827.5 165676 12393 19.6 N/A Sep-96 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 7 << Personnel Travel >> SXT Foreign Travel between 1-SEP-96 and 30-SEP-96 HUDSON 1-SEP-96 * 10-SEP-96 10 16-SEP-96 22-SEP-96 7 (total of 17 days) SAVY 1-SEP-96 * 30-SEP-96 * 30 (total of 30 days) WUELSER 8-SEP-96 30-SEP-96 * 23 (total of 23 days) ---------------------------------------------------------------- Grand Total of 70 days for 3 people NOTE: The "*" signifies travel that actually ends after 30-SEP-96 SXT Foreign Travel between 1-OCT-96 and 31-OCT-96 ACTON 6-OCT-96 31-OCT-96 * 26 (total of 26 days) HUDSON 1-OCT-96 31-OCT-96 * 31 (total of 31 days) SAVY 1-OCT-96 * 24-OCT-96 24 (total of 24 days) SLATER 1-OCT-96 31-OCT-96 * 31 (total of 31 days) WUELSER 1-OCT-96 * 4-OCT-96 4 (total of 4 days) ---------------------------------------------------------------- Grand Total of 116 days for 5 people NOTE: The "*" signifies travel that actually ends after 31-OCT-96 Respectfully submitted, James R. Lemen Frank M. Friedlaender Page 8 ================================================================= Montana State Univ Activity Report for August 1996-September 1996 ================================================================= (L ACTON) == MAJOR ACTIVITIES FOR AUGUST/SEPTEMBER ====================== The MSU Solar Group has continued to play a role in the Yohkoh program, while adjusting to its newfound size and the beginning of another academic year. In this period the MSU-SG has: helped support Yohkoh operations and outreach, analyzed Yohkoh- and other instrumental data, hosted a major scientific meeting, attended various scientific and organizational meetings, submitted manuscripts for publication, hosted a conference, and geared up for relocation to the new Engineering and Physical Science building. Several personnel changes have taken place. David Alexander departed for Lockheed-Martin, where he will continue to work on SXT and the Yohkoh Public Outreach (YPOP) program. David McKenzie, of the University of Delaware, informally accepted Acton's offer of the SXT/YPOP postdoctoral position, to take over some of David Alexander's duties. Other personnel changes included the arrival of Alex Pevtsov, who will work with Canfield on various aspects of magnetic helicity using Mees and Yohkoh data, and Charles Kankelborg, who will work with Acton on TRACE. Weston passed his PhD written comprehensives (congratulations!!) and spent time on the preparation and delivery of his oral examination. Another grad student within the group, Brian Welsch, also achieved a PhD-pass! Acton led the way on outreach efforts, addressing all incoming freshmen as part of the MSU orientation program for new students. He and Michelle Larson also got Tim Slater and MSU's NetTeachTalent signed up to assist in producing Internet-compatible educational materials for YPOP. Larson produced a "sundial page" for the YPOP project, and attended a meeting at NASA for NASA-related outreach projects. Before his move, Alexander began work on Solar Cycle and Solar Rotation pages for YPOP. Canfield has supported operations as the Mees Yohkoh Duty Scientist twice within the report period. Acton devoted most of his time (as well as Weber's) in August to hosting the Chapman Conference on Coronal Mass Ejections. The extensive preparations of months past paid off, and the first solar science conference of the MSU Solar Group appears to have made a good impression on the community. For an encore, Acton has begun planning for the SPD meeting to be held at MSU in late June, 1997. Refer to the "PUBLICATIONS" section for a list of recent papers. At the Chapman conference, Canfield, Reardon, and Pevtsov presented a paper on helicity charging prior to the Nov 15, 1991 flare eruption. Page 9 On a hardware note, Canfield has been integrating equipment from U Hawaii into the MSU-SG computer system. To assist with ongoing system management for the group, he advertised for, and hired, Computer Science graduate student Michael Foley. He and Pevtsov have also taken on undergrad Sean Sandborgh to work on large-scale magnetic flux systems using SXT data. Alexander hosted Joseph Khan so they could work on non-thermal line broadening in compact limb flares. This work is being done together with Louise Harra-Murnion and Sarah Matthews of MSSL. Alexander attended the Chapman Conference where he was a group discussion leader for the CME signatures group. On the science front, he completed the analysis of Peres' flare data using Peres' model and his own geometry code. This work is on-going with MSU grad student Dave Weston. Bargatze has made continued progress on Yohkoh extended corona images. The goal of the effort is to produce images with a wide field of view. At present, he is assembling a status report to provide an overview of the wide field coronal image software development and data analysis. Weber was deeply involved with the Chapman Conference (as Deputy Chair of the LOC) during the month of August. The implementation of NIS on the MSU-SG computer system caused various problems, and he spent some time learning a bit more system management lore from the group's gurus: grad students Kellen and Handy. The remainder of the period was spent on research (effects of convolution on his analysis of coronal differential rotation using SXT images), on study (redoubled effort at assimilating the literature and gaining a foundation in solar physics), and on resolving a thesis topic (something involving causes and evolution of the "large"-scale solar coronal magnetic structure). == PLANS FOR OCTOBER AND NOVEMBER ============================= Acton will be in Japan for most of this period, serving as SXT Chief Observer and attending the Yohkoh 5th anniversary meeting at Yoyogi. Canfield, and Longcope will also participate. Canfield will work with Pevtsov and Sandborgh on large-scale patterns of helicity and the relationship between twist and writhe in photospheric and coronal structures. Weber will go to ISAS for SXT CO and tohban duties in November and December. Bargatze will depart MSU for a research position at the Solar Terrestrial Environment Laboratory (STELAB) and Nagoya University with support from the Japan Society for the Promotion of Science and the Japanese Ministry of Education (Monbusho). == PUBLICATIONS AND PRESENTATIONS DURING AUGUST/SEPTEMBER ===== Papers submitted. "Coronal Heating and the Vertical Temperature Structure of the Quiet Corona", M. S. Wheatland, P. A. Sturrock, and L. W. Acton, submitted to Astrophys. J. Page 10 "X-ray and Radio Microflares in the Magnetic Network of the Quiet Sun", S. Krucker, A. O. Benz, T. S. Bastian, and L. W. Acton, submitted to Astron. & Astrophys. "Yohkoh Soft X-ray Determination of Plasma Parameters in a Polar Coronal Hole", C. A. Foley, J. L. Culhane, and L. W. Acton, to be submitted to Astrophys. J. "Magnetic Reconnection, Magnetic Twist, and Solar Coronal Eruptions", Canfield, Pevtsov and Reardon, submitted to the Hitachi workshop proceedings. "What is the Spatial Relationship Between Hard X-Ray Footpoints and Vertical Electrical Currents in Solar Flares?", Canfield, Li, Metcalf, Wuelser, and Kosugi, submitted to Astrophys. J. Papers accepted. "Fine Structure of the X-ray and Radio Emissions of the Quiet Solar Corona", A. O. Benz, S. Krucker, L. W. Acton, and T. S. Bastian, Astron. & Astrophys. (in press, Sept. 1996). Page 11 ======================================================================= Univ of Calif, Berkeley Activity Report for August 1996-September 1996 ======================================================================= J. McTiernan has spent the last two months looking into the scattering of X-ray photons by the ND filter. The results from a study of alternating ND and OPEN images with effective exposure times of 3.1 msec and 2.9 msec, for 36 flares between Oct-1991 and Mar-1992 can be found now on the Web at: http://sprg.ssl.berkeley.edu/~jimm/nd_scatter.html and the effects of the ND filter on SXT temperature measurements can be found after 4-oct-1996 at: http://sprg.ssl.berkeley.edu/~jimm/nd_scatter_t.html (1) The effective ND filter transmission efficiency varies by about 4% over the range from the CCD center to the solar limb. This can be corrected for by multiplying the ND filter transmission value or the effective exposure time by 1.0+1.0e-4*R, where R is the distance in pixels from the CCD center. Note that this assumes that the value of 0.0805 used for the ND filter transmission is correct at R=0. (2) Scattering by the ND filter removes an average of approximately 4% of the photons from the peak of a point source, and results in a point spread function that is approximately 0.1 pixels wider than it would be in the absence of the ND filter. (3) These are small effects, of only a few percent. In any calculation of Temperatures or Emission Measures, the uncertainty due to photon statistics is larger. All other things being equal, the use of the ND filter for Al.1 images causes an increase in Temperature of approximately 2%, and a decrease in Emission Measure of approximately 4% for the brightest parts of a flare. These results were obtained using Al.1/Be119 filter pairs for the sample of 36 flares. Emission scattered out of a bright source by the ND filter will only have a small effect on nearby dimmer sources; those which are only a few percent of the brightness of the main source, and within 1 or two pixels of the main source. Page 12 ============================================================= Univ of Hawaii Activity Report for August 1996-September 1996 ============================================================= As a result of a blunder on the part of one of the editors (JRL) we failed to receive the Hawaii report in time for submission. We will present the Hawaii report in next month's report. ============================================================ Stanford Univ Activity Report for August 1996-September 1996 ============================================================ During the reporting period Slava Glukhov completed his Ph.D. thesis, entitled "Stability and equilibrium of coronal helmet streamers." Included is a detailed analysis of SXT observations of the birth and evolution of a giant coronal helmet streamer, which suggests that the energy source responsible for the X-ray manifestation of the structure is located in the lower corona, and supplies energy to the top of the structure where it is dissipated. The structure is shown to be in non-isothermal hydrostatic equilibrium, once projection effects are accounted for. A paper on this topic has been accepted for publication and will appear in the Astrophysical Journal. Roumeliotis has continued work on a variational method for reconstructing force free-fields in the solar corona. Simulations performed for comparison with analytically calculable fields demonstrate the reliability of the method, which has the advantage of being based on a sound theoretical foundation, rather than relying on a heuristic approach. A paper is being prepared on this topic. Wheatland has submitted to the Astrophysical Journal a paper describing the results of his collaboration with Peter Sturrock and Loren Acton on an analysis of SXT observations of two regions of extended, diffuse corona, and its implications for coronal heating in the quiet corona. He has also begun work on the calculation of the thermodynamics of extended, space filling magnetic loop systems as a follow-up to this work. Wheatland has also continued work on a new model of the statistics of flares, which describes the free energy of an active region as a steady state balance between stochastic energy loss (flaring) and energy resupply. The model was formulated as an alternative to the avalanche picture but it is possible that it is a complementary description. The model differs from previous, similar models in permitting flares which do not completely deplete the free energy of an active region. A paper will be prepared on this topic. Papers submitted: Page 13 Wheatland, Sturrock and Acton, "Coronal Heating and the Vertical Temperature Structure of the Quiet Corona," submitted to ApJ Sturrock, "A Conjecture Regarding the Rieger and Quasi-Biennial Solar Periodicities," submitted to ApJ Sturrock and Walther, "An Apparent Periodicity in the Gallex, Homestake and Kamiokande Neutrino Data," submitted to ApJ Papers accepted: Glukhov, "Thermodynamics and Morphology of a Helmet Streamer Observed by the Yohkoh Soft X-ray Telescope," to appear in ApJ (Feb 10 1997 issue) Page 14 =========================================================================== Solar Physics Research Corp. Activity Report for August 1996-September 1996 =========================================================================== Karen L. Harvey and Hugh S. Hudson Karen L. Harvey: (1) As a result of the InterAgency Consultative Group Campaign IV (IACG-C4) Workshop on "Open and Closed Solar Fields and the Solar Wind" held in Switzerland, July 8-12, an IDL program is now being developed to allow drawing of the irregular coronal hole boundaries on the NSO/KP He I 10830 spectroheliograms. This program also places the boundaries on the corresponding daily full-disk magnetograms to verify the unipolar fields in the candidate coronal hole. Once completed, the products of this coronal hole program are (1) two maps of the coronal hole boundaries on a stonyhurst disk that matches the low- and high-resolution images, (2) measures of the total magnetic flux, the net magnetic flux, mean total and net field, area in km^2 and as a fraction of the visible disk, type of hole (polar, isolated, extension, transient), the heliographic location of all identified coronal holes on each days observation and the identification certainty. A second file lists the boundaries of the coronal holes in heliographic latitude and longitude at increments of 3 to 5 degrees for use by the solar-wind/interplanetary community. Another program will apply solar rotation and rescale the coordinates of the coronal hole boundaries for application to other images, such as the Yohkoh/SXT images. The program will be implemented on the current daily NSO/KP observations and then to extend the coronal holes maps through the Yohkoh period (late 1991 to fall 1996. This will provide an extensive data base for direct comparison of coronal hole boundaries seen in the Yohkoh/SXT images and He I 10830 spectroheliograms. (2) Continued analysis of observations of XBPs obtained though a collaboration of several ground-based observatories and the Yohkoh SXT instrument, and SOHO in early April and late May 1996. Some of the SOHO data have been made available for an initial comparison of data on 12 April 1996. These data include line profiles of He I 10830 using the NSO/KP spectromagnetograph, photospheric magnetograms from the MDI, and intensity images in He I 584 and Mg X 625 from CDS spectra. These comparisons will be presented at a meeting on "Advances in the Physics of Sunspots" (to be held October 2-6, 1996 at Tenerife, Spain) in a session on the Coordination of SOHO and ground-based observations; the title of this talk is Coordinated Satellite and Ground-Based Observations of X-ray Bright Points. Future plans are to complete the data analysis of the 150 XBPS observed in the spring 1996 campaigns working with Ted Tarbell (MDI), A. Fludra (CDS), D. Hassler (SUMER), and D. Moses (EIT). (3) Continued analysis of the collaborative observations of XBPs obtained in the several XBP campaigns between Yohkoh/SXT, NSO/KP, MSO, BBSO, HAO, Page 15 SOONSPOT. Plan is to complete by early next year a paper presenting the results of the association of XBPs with the evolution of the magnetic fields and chromospheric structures. (4) Planning of another XBP campaign for late October 1996. For this run, NSO/KP will obtain high-spatial and temporal magnetograms in the chromosphere for comparison with XBPs. (5) Preparation of NSO/KP full-disk magnetograms and He I 10830 spectromagnetograms for SXT investigators for studies of the magnetic field and He I 10830 structures associated with X-ray structures. (6) Continued collection and updating of the bibliography of Yohkoh papers. Hugh H. Hudson: H. Hudson participated in Yohkoh operations at ISAS and spent most of his research time on the general subject area of the large-scale corona. This included participation in the Chapman Conference on CMEs (Bozeman, Montana), and preparation of the manuscript for its conference proceedings. There are many interesting aspects of the Yohkoh observations related to CMEs. Hudson's work continues with Dave Webb on classification and possibly with Jim Klimchuk on physical interpretation. The idea of the latter is that the dimming signature itself, when properly folded through the instrument response function, contains information about the flow field even in cases where there is no well-defined expanding structure. Hudson also worked with analysis of time-series observations of solar X-rays, as described in the paper by Ueno et al. (Ap. J., submitted) and in work in preparation for the Yoyogi meeting in November (the active region of the July 1996 X-class flare, and its subsequent rotations). This work will be the basis of Hudson's poster presentation at the Yohkoh 5th anniversary meeting. PLANS FOR OCTOBER AND NOVEMBER Hudson intends to continue pursuing the collaboration with Dave Webb on a first comprehensive review the dimming signature. Preliminary work on this subject was presented at the Chapman conferences on geomagnetic storms (JPL, February) and on CMEs (Bozeman, August), including the Webb et al. poster that introduced our tentative classification of dimming events into four categories. If time allows, the observations of Type II bursts reported at the SPD meeting will be written up. Hudson hopes also to make some time available for HXT data analysis in preparation for the CDAW planned for January at Palo Alto. Papers submitted "Statistics of fluctuations in the solar soft emission", by S. Ueno, S. Mineshige, H. Negoro, K. Shibata, and H.S. Hudson, submitted to Ap. J. (September, 1996). Page 16 Papers accepted "Magnetic storms: current understanding and outstanding questions", by Y. Kamide, R. L. McPherron, W. D. Gonzalez, D. C. Hamilton, H. S. Hudson, J. A. Joselyn, S. W. Kahler, L. R. Lyons, H. Lundstedt, and E. Szuszczewicz, proc. Chapman conference on magnetic storms "The solar antecedents of geomagnetic storms", by H.S. Hudson, proc. Chapman conference on magnetic storms "Coronal X-ray dimming in two limb flares", by H.S. Hudson, J.R. Lemen, and D.F. Webb, Proc. Bath conference, August 1996 Page 17 ------------------------------------------------------------------------------- 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 October 1996 September 1996 |------------------------------- | 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 - 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 | of September 1996 |------------------------------- |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 | 17 | ------------------------|------------------------|-----------------|----------- For sale by: Superintendent of Documents, U.S. Government Printing Office