Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-00119) (for November 2000) OVERVIEW The YOHKOH Mission is a program of the Japanese Institute of Space and Astronautical Science (ISAS) with collaboration by the U. S. National Aeronautics and Space Administration and the U. K. Science and Engineering Research Council. The YOHKOH satellite was launched on 30 August 1991 from Kagoshima Space Center (KSC) in Japan. The purpose of this mission is to study high energy phenomena in solar flares and the Sun's corona. Under an international cooperative agreement, Lockheed Martin, under NASA contract, is providing a scientific investigation using the Soft X-ray Telescope (SXT), one of the primary experiments of the mission. The SXT was developed at the Lockheed Martin Solar and Astrophysics Laboratory in cooperation with the National Astronomical Observatory of Japan, and the Institute for Astronomy of the University of Tokyo. MAJOR PROGRAMMATIC ACTIVITIES IN THE MONTH Programmatic support in Japan has been enhanced by having a full time software person in residence. This should provide more extensive coverage and better support for visiting scientists. SOLAR ACTIVITY In early November, solar activity was low. However, after about 7 November activity picked up, with at least 10 M-class flares (including a M7 LDE) and many C-class flares. The GOES background level also increased until the M7 flare at which time it decreased for about 2.5 days. Solar activity remained moderate through mid-November. AR9231 showed remarkable magnetic evolution yielding M- and C-class flares. This region was selected at the target of both the ASP and MEOC campaigns. Solar activity increased spectacularly at the end of November. The Sun produced five X-class flares, all of them from AR 9236 near disk center. However, there was an M8 from AR9240, thus confounding those who claim that two regions cannot make major flares at the same time. Counting M and X class flares, there were about 18 events during November. The X-class flares were all compact, impulsive, and associated with halo CMEs. Yohkoh apparently has good coverage for all but the first, and from that one an interesting and possibly new form of dimming appeared in the before-and-after difference images. This region was selected as the target of the MEOC campaign. After the string of X-class flares, the last of which was an X4 at 11/26 Page 2 16:48, the sun was very quiet. In the 7 days that followed, only two M-class flares and no X class flares were observed. GOES background level remained at C1. CAMPAIGNS Yohkoh supported the MEOC campaign, looking for EIT-type waves, and will continue to do so until 8-Dec. The ASP (Sacramento Peak Observatory) campaign of Shimizu & Kubo to study magnetic structure and heating ran successfully from the 14th through 22nd of November. SCIENCE On November 3, McKenzie observed an X-ray jet just north of the center of the solar disk. The very well observed example of a jet stretched for more than 280 thousand kilometers. We don't know precisely when it began growing, because the jet was already visible when Yohkoh came out of the Earth's shadow; but in the span of just 6 minutes the jet doubled in length. Right away we start to see some interesting details. First this jet is a "repeater", meaning that after the first eruption, there is a second brightening. This is fairly common. Second, the jet is not perfectly straight. It's slightly curved to the west, and even appears to change shape as it progresses. The path and shape are determined by the magnetic field which confines the hot plasma -- an open question is whether the other end of this magnetic field is located on the Sun, some distance away, or far out in space (i.e., is the field closed or open?). In the present case, we believe the jet is open to space. TRACE images show that in the foot of the jet, there are coronal loops stretching from one side of the foot region to the other. The dipolar nature of the magnetic field is made apparent, despite the fact that this event is defined by material flowing out into space. And yet the footpoints of these loops do not leave the boundary of the "conduit". If we suppose that the "conduit" of the jet represents field lines that are open to space before the jet event, then what would result if some magnetic flux just happened to emerge within the conduit? It seems possible that a reconnection of the emerged field with the lines open to space could produce the brightening, the energy of the material ejected in the jet, and the apparent connection between footpoints on opposite sides of the jet base. The boundaries of the "conduit" would certainly be perturbed by such an interaction, but not necessarily violated; this might give us a reason why the brightening at the base does not appear to leave the confines of the "conduit" boundary. This is not so different from previous explanations of jets, like the cartoon of Heyvaerts, Priest, and Rust, or the works of Shimojo and Shibata. In this case, we are simply placing the emergence of flux Page 3 entirely within the collection of previously-open field lines, and not allowing it to stray outside. Mix in some reconnection, add just a pinch of rank speculation, and voila! In October, SXT images showed us an unusual feature, the apparent brightening of a cusp. Of course, we knew it happened, but it's nice to see it in action. On a solar scale, this was not a large event. The GOES spacecraft, which records the total amount of X-rays from the whole Sun, shows only a tiny and insignificant rise in the X-ray background. But light curves from the SXT movie, wherein we can measure the brightness in a specific region, demonstrate the filling in of the upper part of the structure. The SXT data show plasma filling in from below -- it does not appear to be "thrown" upwards like the ejecta in some flares. The cusps are believed to be filled in by plasma rising up from the lower atmosphere, in a process called "chromospheric evaporation", or equally "chromospheric ablation". As a result of the reconnection of the magnetic field lines, a great deal of energy is conducted down to the chromosphere; this then heats the chromospheric plasma, which injects itself into the just-formed loops. PUBLICATIONS Submitted: Aschwanden,M.J., Poland,A.I., and Rabin,D. 2001 Ann.Rev.Astron.Astrophys. 39, "The New Solar Corona" URL="http://diapason.lmsal.com/~aschwand/araa/araa.html" "Active Region Transient Brightenings: A Simultaneous View by TRACE, EIT, and SXT", by Berghmans, D., McKenzie, D., and Clette, F., Astronomy & Astrophysics. The paper "Hard X-rays from Slow LDEs", by Hudson, H.S. and McKenzie, D.E., re-submitted to the Proceedings of The University of Tokyo Symposium in 2000 on Magnetic Reconnection in Space and Laboratory Plasmas. Accepted: Sturrock, P.A., Weber, M., Wheatland, M.S., & Wolfson, R. 2000, Metastable Magnetic Configurations and their Significance for Coronal Mass Ejections. ApJ, in press. Hudson, H. and Cliver, E., "Non-Coronagraphic Observations of Coronal Mass Ejections": 2000, J. of Geophys. Res., in press Aschwanden,M.J. and Acton,L.W.2001 ApJ 550, ... (2001 March 20 issue, in press) URL="ftp://sag.lmsal.com/pub/aschwand/2000_acton.ps.gz" "Temperature tomography of the soft X-ray corona: measurements of Page 4 electron densities, temperatures, and differential emission measure distributions above the limb" Pevtsov, A. A. and Canfield, R. C. ``Solar Magnetic Fields and Geomagnetic Events", JGR, accepted, 2000. "Closure on Mesospheric/Thermospheric Nitric Oxide Abundance" P. K. Swaminathan, D. F. Strobel, L. Acton and L. J. Paxton, Physics and Chemistry of the Earth, in press. "Supra-arcade Down-flows in Long-duration Solar Flare Events", D. E. McKenzie and H. S. Hudson, in the book "Magnetic Reconnection in Space and Laboratory Plasmas", a special issue of the journal "Earth, Planets and Space (EPS)". "Evidence for the Flare Trigger Site and 3-D Reconnection in Multi-Wavelength Observations of a Solar Flare", Fletcher, L., Metcalf, T. R., Alexander, D., Brown, D., and Ryder, L. A. ApJ, in press. Published: Wolfson, R., Roald, C.P., Sturrock, P.A., Lemen, J., & Shirts, P. 2000, Temperature Structure of the Quiet Corona: an SXT-SUMER Discrepancy, ApJ, 529, 570. PUBLIC USE OF SXT IMAGES We are continuing to make Yohkoh/SXT images available for a variety of uses. Efforts continue to make selected images available on the LMSAL SXT WWW homepage (http://www.lmsal.com/SXT/). We receive requests for the Yohkoh posters (#2 and #3) by way of the form on the SXT homepage. Currently we receive requests via our homepage at the rate of 2 or 3 per day. The WEB access statistics in November were 140237 accesses and 8975 Mbytes transferred for the SXT website and 172669 accesses and 4024 Mbytes transferred for the YPOP website. YOHKOH OPERATIONS AND HEALTH Yohkoh and the SXT continue to function very well. SXT experienced a normal level of Single Event Upset (SEU) events during the month: Bit Map Error 01-Nov-00 Pass 5: 001101-1239 Recovered in the same pass Bit Map Error 18-Nov-00 Pass 1: 001118-0411 Recovered in the same pass Page 5 DATA FLOW Month Full Frame Images Observing Region Images Received Lost Received Lost Loss % QT FL Tot Thru Sep-98 571717 213233 2300124 510469 2810593 1028333 26.53 Oct-98 6573 1901 23520 5198 28718 9220 24.30 Nov-98 6442 1695 25124 26948 52072 9920 16.00 Dec-98 5962 2005 21490 15770 37260 10561 22.08 Jan-99 5494 1825 20087 17620 37707 9622 20.33 Feb-99 5729 1525 30802 9798 40600 10630 20.75 Mar-99 6807 1844 24721 12354 37075 10064 21.35 Apr-99 6715 1371 25113 4179 29292 7791 21.01 May-99 6459 1807 35467 12092 47559 13757 22.44 Jun-99 6217 1915 23542 13051 36593 10086 21.61 Jul-99 5591 1745 20409 25747 46156 9670 17.32 Aug-99 6827 2503 21725 23361 45086 11844 20.80 Sep-99 5768 2011 21890 3434 25324 10846 29.99 Oct-99 5768 2308 22994 10487 33481 11517 25.59 Nov-99 7552 3425 20754 18772 39526 11974 23.25 Dec-99 7488 2791 22047 5354 27401 10663 28.01 Jan-00 5426 1736 19802 4040 23842 8958 27.31 Feb-00 6533 2052 21801 7017 28818 8982 23.76 Mar-00 6447 2007 22692 21914 44606 11192 20.06 Apr-00 6412 2100 31195 7214 38409 13438 25.92 May-00 6995 1556 28175 14961 43136 8967 17.21 Jun-00 7043 1722 24413 16369 40782 8690 17.57 Jul-00 6674 1920 23505 31739 55244 10235 15.63 Aug-00 9623 1996 20925 1197 22122 6577 22.92 Sep-00 8835 2240 22233 5764 27997 8307 22.88 Oct-00 5687 1315 20881 5949 26830 6911 20.48 Total 736784 262548 2895431 830798 3726229 1278755 25.55 Number of Full Frame Images Received: 736784 Number of Observing Region Images Received: 3726229 Total: 4463013 Approximate Number of Shutter Moves/CCD Readouts: 7584842 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 (%) Oct-98 57.59 1015.3 220504 30221 21.3 N/A Nov-98 58.17 1037.0 223755 34614 22.5 / 2 23.4 N/A Dec-98 57.86 1025.5 221918 32420 23.8 N/A Jan-99 58.74 1058.6 227503 38238 23.1 N/A Feb-99 58.44 1047.4 224002 36198 23.2 N/A Mar-99 59.26 1078.1 227900 43051 21.7 N/A Apr-99 58.82 1061.4 225973 38963 23.8 / 1 21.4 N/A May-99 58.68 1056.4 225385 37726 21.6 N/A Jun-99 59.40 1083.0 230091 42440 22.0 N/A Jul-99 59.78 1097.5 231236 46337 23.8 / 1 20.6 N/A Aug-99 59.39 1083.0 229319 43067 21.7 N/A Sep-99 60.04 1107.3 231585 49084 21.8 N/A Oct-99 59.66 1092.9 229735 45263 22.8 N/A Nov-99 59.90 1102.0 231288 47102 23.0 N/A Dec-99 60.55 1126.3 233523 53920 22.5 / 2 25.3 N/A Jan-00 60.27 1115.9 233820 50214 23.4 N/A Feb-00 60.93 1140.6 235079 56836 23.8 N/A Mar-00 60.72 1132.8 234174 54661 22.9 N/A Apr-00 61.10 1147.0 235252 58348 22.2 N/A May-00 61.00 1143.1 234569 57445 21.2 N/A Jun-00 61.19 1150.3 235622 58946 22.8 N/A Jul-00 61.96 1179.3 238114 66905 19.3 N/A Aug-00 61.27 1153.4 236108 59965 56.9 / 2 21.7 N/A Sep-00 61.08 1146.2 235644 58449 22.1 N/A Oct-00 61.21 1151.2 236431 59204 23.1 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-NOV-00 and 30-NOV-00 HUDSON 11-NOV-00 26-NOV-00 16 (total of 16 days) MCKENZIE 1-NOV-00 * 15-NOV-00 15 (total of 15 days) SLATER 22-NOV-00 30-NOV-00 * 9 (total of 9 days) TAKEDA 1-NOV-00 * 30-NOV-00 * 30 (total of 30 days) ---------------------------------------------------------------- Grand Total of 70 days for 4 people NOTE: The "*" signifies travel that actually ends after 30-NOV-00 SXT Foreign Travel between 1-DEC-00 and 31-DEC-00 BARTUS 3-DEC-00 31-DEC-00 * 29 (total of 29 days) HUDSON 2-DEC-00 9-DEC-00 8 28-DEC-00 31-DEC-00 * 4 (total of 12 days) SLATER 1-DEC-00 * 4-DEC-00 4 7-DEC-00 22-DEC-00 16 (total of 20 days) TAKEDA 1-DEC-00 * 28-DEC-00 28 (total of 28 days) ---------------------------------------------------------------- Grand Total of 89 days for 4 people NOTE: The "*" signifies travel that actually ends after 31-DEC-00 Respectfully submitted, Thomas R. Metcalf Frank Friedlaender Page 8 ========================================================================= Montana State University Activity Report for October 2000 - November 2000 ========================================================================= (R. Canfield) INTRODUCTION The MSU group carried out SXT operations, data analysis, graduate and undergraduate research, participated in meetings, and performed outreach activities. A highlight of this period was the selection of the SXT "Nuggets" by the Scout Report for Science & Engineering, the premier biweekly collection of useful Internet sites for researchers, educators, and students in the life sciences, physical sciences, and engineering. YOHKOH AND SXT OPERATIONS McKenzie spent the second half of October and the first half of November at ISAS, serving as SXT co-Chief Observer with Takeda san. He took part in two observing campaigns, collaborating with SOHO, TRACE, and several ground-based observatories: the Moreton-EIT wave Observing Campaign, and an Active Region Coronal Heating observing campaign. Yohkoh had an attitude anomaly early in the month, but that was cleared up within a few days. Canfield served as Yohkoh Duty Scientist at Mees Solar Observatory the week of Oct 31 - Nov 6. MEETINGS McKenzie participated in the First S-RAMP Conference at Sapporo, Japan, Oct. 2-6, giving an invited talk, "Sigmoidal Morphology as a CME Predictor". Canfield participated in the Third Whole Sun Month workshop at Goddard, November 13-15, working on the analysis of coordinated Yohkoh/SoHO/TRACE/GBO observations of the sigmoidal active region AR 8668. RESEARCH McKenzie found two new supra-arcade down-flow events, in the eruptive (sigmoid!) flare of 25-Oct-00 and in an M flare of 9-nov-00, bringing the number of known events to 20 in less than three years of observations. Working with Hudson and Rust, he carried out the initial analysis of a thermal front, propagating along the length of a filament channel. He analyzed an X-ray jet from 3-nov-00 , which is an outstanding example of the phenomenon (see nugget of November 10, 2000: "A beautifully observed X-ray jet". As part of JOP 104, he analyzed and Page 9 summarized SXT observations of 25-Oct and 26-Oct events. The former has an apparent cusp brightening directly intersecting the SUMER slit; the latter is an eruptive C8 flare, with soft X-ray ejecta crossing the SUMER slit. Canfield started working with new Postdoctoral Fellow Bob Leamon on the interplanetary signatures of eruptions that occurred in Yohkoh X-ray sigmoids. He continued to work with Jibben on the comparison of SXT jet / MCCD surge events to maps of twist in photospheric magnetic fields, inferred from Mees vector magnetograms. Jibben finished this comparison and discovered a statistically compelling relationship between the direction of spin of surges and the handedness of twist in magnetic fields at their apparent point of origin. She started on a manuscript as part of an undergraduate research course (Physics 490). Canfield continued to work with Colman on a paper on moving blue-shift events in the Mees data, based on Wuelser's list of the best observed Mees/Yohkoh flares. Colman found a significant relationship between the frequency of preflare moving blue-shift events and the eruptive nature of the flares, and started on a manuscript as part of an undergraduate research course (Physics 490). Canfield worked with MSU undergrad Yuriko Yamazaki to make CDs of Mees coronagraph prominence eruptions for comparison with SXT events. These CDs are being sent to Tonooka san at Chiba University. He worked with Nitta, Zarro, LaBonte, and others on the interpretation of SXT and other "sigmoid" observations obtained during Whole Sun Month 3. He worked with Alexei Pevtsov and Sergei Latushko on paper on the hemispheric helicity rule for solar cycle 23". Among other things, they used SXT images of sigmoids to show that the hemispheric helicity rule is the same during first four years of cycle 23, as it was in Cycle 22. Martens prepared a bit for the SXT deconvolution workshop in January in Hawaii, by looking at his old PSF results and Blind Iterative Deconvolution. He also continued to work with dePontieu and Hudson on chromosphere/ corona reflection coefficients larger than one. Acton wrote and tested a program, sxt_suture.pro, to do a better job of correcting the bleed areas in SXT composite images. Davey tuned and upgraded the MSU workstation SXT4 to provide improved access to the new SXT science composite images (SSCs). SERVICE AND OUTREACH McKenzie designed and built a new Yohkoh web site, to put all the Yohkoh links in one place: http://isass1.solar.isas.ac.jp/~sxt_co/ He assisted in relocating the U-side SXT presence in Fuchinobe. As part of YPOP, he gave assistance to a teacher-education coordinator at DePaul. Canfield reformatted the SXT weekly reports as Nuggets, on the web at http://solar.physics.montana.edu/nuggets/ and mirror sites at Lockheed, ISAS, and MSSL. Page 10 Martens refereed a paper for ApJ and continued teaching the course "Plasma Physics & MHD". Davey worked on the usual round of general user support, security fixes, software upgrades and the SUN/DEC integration problems. The only other major project is the one regarding the 2TB of storage for direct disk storage of the entire SXT database. PUBLICATIONS: Papers Accepted: ---------------- "Closure on Mesospheric/Thermospheric Nitric Oxide Abundance" P. K. Swaminathan, D. F. Strobel, L. Acton and L. J. Paxton, Physics and Chemistry of the Earth, in press. "Supra-arcade Down-flows in Long-duration Solar Flare Events", D. E. McKenzie and H. S. Hudson, in the book "Magnetic Reconnection in Space and Laboratory Plasmas", a special issue of the journal "Earth, Planets and Space (EPS)". "Solar Magnetic Fields and Geomagnetic Events", A. A. Pevtsov and R. C. Canfield, JGR, accepted, 2000. Papers Submitted: ----------------- "Active region Transient Brightenings. A simultaneous view by SXT, EIT and TRACE", D. Berghmans, D. McKenzie and F. Clette. submitted to Astronomy & Astrophysics. Talks Given: ------------ "Sigmoidal Morphology as a CME Predictor", McKenzie, D., Canfield, R. C., Hudson, H. S., Pevtsov, A. A., and Blehm, Z., invited talk at the First S-RAMP Conference at Sapporo, Japan, Oct. 2-6. "Down-flows above LDE flare arcades", McKenzie, D.E., seminar, Kwasan Observatory of Kyoto University, October 10, 2000. "The Sun Earth Connection in the Space Age", R. C. Canfield, Physics 100 (Physics Today), MSU Bozeman, October 26, 2000. "In a Golden Age of Solar Physics: Results from Yohkoh, SOHO, and TRACE", P. Martens, seminar, Memphis State University Page 11 ============================================================= Univ of Hawaii Activity Report for October 2000 - November 2000 ============================================================= (B. LaBonte) Our activities included support of Yohkoh operations and data analysis at ISAS, coordinated ground-based data acquisition (including designated Yohkoh campaigns) at Mees, collaborative analysis of Yohkoh/Mees data, and preparation of manuscripts. Operational support for SXT was provided by G. Nitta at Mees and LaBonte and Li in Manoa. Our colleagues Kupke at Manoa, Canfield at Montana State University, Wuelser and Metcalf at Lockheed, and Hudson at Solar Physics Research Corporation aided in advice and oversight of Mees operations. Weather at Mees was fair in October, poorer in November, as is usual. Observations were obtained on 84% of all scheduled days in October, but only 60% of scheduled days in November. Coupled with the several holidays, the total coverage in November was low. LaBonte worked with R. Canfield (MSU), D. Zarro (GSFC), and N. Nitta (LMSAL) on analysis of active region AR8668 as a part of the Whole Sun Month workshop held in November. Again, this was a remote collaboration, with LaBonte generating electric current maps and ambiguity resolved vector field maps in Hawaii while the meeting was in progress. The topology of the field structure in the flare site of this region on Aug 16 1999 is being critically examined. The IVM data, with high spatial resolution and polarization sensitivity, are challenging the theoretical picture first proposed for this region. LaBonte has been working with T. Metcalf and N. Nitta at LMSAL on several projects comparing the IVM magnetic and current data with SXT, SOHO, and TRACE observations of coronal activity and structure. Nitta will present some of this work at the upcoming AGU meeting. Li is continuing to work on using the SXT images, along with SOHO/EIT and SOHO/LASCO, to deduce the true arrangement of the large-scale coronal structure during the rise phase of the solar cycle. This work is dividing into several distinct areas: novel techniques for structure determination; reconnection in closing down the polar coronal holes; and connectivity between low coronal structure and the solar wind regime. Page 12 ============================================================ Stanford Univ Activity Report for October 2000 - November 2000 ============================================================ (P. A. Sturrock) Peter Sturrock continues to collaborate with Jim McTiernan in Berkeley concerning the optimization-function approach to the reconstruction of force-free magnetic field configurations from photospheric vector magnetograph data. The optimization-function method rests on the minimization of the integral of a sum of terms, each term being the square of the error in each relevant equation (the divergence equation and the force equation). Jim has converted his code from C to IDL, and is into the debugging phase. When fully converted to IDL, the program should be more convenient for graphics output and for comparison with data. For more information, see the UC Berkeley contribution to this report. Continuing with his investigation of CME energetics and the Aly- Sturrock theorem, Mark Weber has found (using a numerical procedure) promising force-free field (FFF) stable solutions for flux tubes belted about the solar equator, with energies greater than that of the open dipole configuration. Such solutions provide a model for metastable magnetic field configurations which contain sufficient energy to drive coronal mass ejections (CMEs). Mark is currently studying these solutions to evaluate the rigor of the estimates of the stable field and energy content. Peter and Mark are beginning a new project. For several years, Peter has been studying solar neutrino data, with several collaborators, and with support from other grants. These studies have yielded strong evidence that the solar neutrino flux varies in time. A major component of the variation is associated with solar rotation. In view of these positive results, we have decided to review some earlier claims that the solar neutrino flux is correlated with coronal emission. The earlier studies utilized data from ground-based green-line coronagraphs. SXT provides greatly superior data, and has now been running long enough that it seems reasonable to compare the SXT time series with the neutrino time series. We expect that there will be a correlation, but - if there is - the big question will be whether the correlation is due simply to the fact that both time series show rotational modulation, or whether there is evidence that coronal emission responds to the same sub-surface magnetic structures that we believe to be responsible for rotational modulation of the neutrino flux. It is too early to report any results on this project. PUBLICATIONS Sturrock, P.A., Weber, M., Wheatland, M.S., & Wolfson, R. 2000, Metastable Magnetic Configurations and their Significance for Page 13 Coronal Mass Ejections. ApJ, in press. Wolfson, R., Roald, C.P., Sturrock, P.A., Lemen, J., & Shirts, P. 2000, Temperature Structure of the Quiet Corona: an SXT-SUMER Discrepancy, ApJ, 529, 570. =========================================================================== Solar Physics Research Corp. Activity Report for October 2000 - November 2000 =========================================================================== (K. Harvey) KAREN L. HARVEY: Activities for October and November: 1. Continuing a comparison of the coronal holes identified in NSO/KP He I 10830 rotation maps and with corresponding Yohkoh/SXT rotation maps to determine if the structures identified as coronal holes in He I 10830 all are associated with low emission areas. Of particular interest is the development of the new polar coronal holes following the reversal of the polar magnetic fields and of isolated (non-polar) coronal holes in association with active regions. There is, for example, a large isolated coronal hole now approaching central meridian extending from about N45 to S35. This hole has persisted for about 5 solar rotations in a relatively quiet part of the Sun. The maintenance of this hole for such a period of time is of interest and the fact that it has shown little distortion from differential rotation. 2. Continued with the analysis of data to determine the magnetic flux with an area bounded by He I 10830 the two flare ribbons and within the associated transient coronal holes as a function of time. The software is being tested on HAO/CHIP He I 10830 images of a two-ribbon flare that occurred on 12 December 1998. Because this event is located at N30 E30, the magnetic fields show the canopy effect, which needs to be taken into account in the determinations of the magnetic flux totals. We are, in one case, eliminating from the measurements areas where the canopy effect is evident, that is around the stronger field elements. Second, we are going to model the magnetic field from the line-of-sight component using code developed by T. Sakuri for force-free fields. We are also comparing the locations of the flare ribbons and transient holes with the SXT images for this event to determine how the arcade and transient coronal holes relate spatially and temporally with X-ray dimming events. As mentioned in previous reports, the objective of this study is to determine the reconnection rate of a flare. Two measurements will be made with time using a singe NSO/KP full-disk magnetogram (this assumes that the photospheric field does not change over the observed life of the flare). Plans for December 2000 and January 2001: Page 14 Continued analysis and study of (1) the association of coronal holes observed in He I 10830 spectroheliograms and the SXT full-frame images; (2) a study with T. Forbes of the reconnection rate of magnetic fields during long-duration arcade events/He I 10830 2-ribbon flares associated with X-ray dimming and transient coronal holes. HUGH S. HUDSON Activities for October and November: 1. Worked with Brigitte Schmieder during her visit in October, involving observations from the FlareGenesis telescope. The particular interesting things included a beautiful emerging-flux region (arch filament system) in which we found X-ray microflare activity, and a remarkable flare-induced activation of a filament cavity (see http://solar.physics.montana.edu/nuggets/2000/001006/001013.html). 2. Attended a small workshop at the International Space Science Institute, convened by Peter Cargill, on flares. Volunteered to survey the "electron number problem" prior to the second session of this workshop, which will be in May 2001. The number problem has always been one of the key issues of flare theory, but there is little recent literature about it and people tend to forget and/or erroneously conclude that somehow the problem has been solved! 3. Worked with visitor Henry Aurass, who on this visit to ISAS has been specifically interested in the X-ray counterparts of dm spike bursts. He also has a long-standing interest in Type II bursts and their association with flare ejecta. 4. Continued to work with new SXT chief observer Aki Takeda in getting oriented. Wrote some science nuggets, being most impressed by the observations of a confined X-class flare with a remarkable expansion seen _only_ in the high-resolution images - why was this not a Type II burst (see http://solar.physics.montana.edu/nuggets/2000/001006/001006.html)? 5. Participated in a NASA review activity in Washington. Plans for December 2000 and January 2001: 1. Prepare for the AGU Fall meeting and present a paper there on observations of the July 14, 2000 flare - there will be two days of sessions on this remarkably well-observed event. 2. Work with Takeo Kosugi on his Fourier-transform analysis of the SXT scattering wings, and attend a small workshop in January on this important subject. 3. Struggle mightily to get the SXT wave paper submitted. This has gone far too long! Page 15 PUBLICATIONS Papers Accepted: Hudson, H. and Cliver, E., "Non-Coronagraphic Observations of Coronal Mass Ejections": 2000, J. of Geophys. Res., in press TAKEDA AKI: Activities for October and November: Three months have passed since I started working for Yohkoh here at ISAS. I have gotten used to most of the regular operations of SXT, for which I should be responsible as one of the chief observers. I experienced several campaign observations with other instruments. The ASP campaign collaborating with the Advanced Stokes Polarimeter from 14 to 22 November was particularly instructive, because it required a special operation, ARS2 mode, in selecting the target region in partial frame images. With David McKenzie's assistance I calculated the position of the given target at the time of the table uplink, and specified the CCD coordinates in the table. At present, writing a "science nugget" each week is one of the biggest challenges for me. I finished my first nugget in October: http://isass1.solar.isas.ac.jp/sxt_co/001020.html, which describes the disk passages of a beautiful coronal hole which appeared on the solar disk during this period, but the second nugget is still under construction. On 2th November we had guests (V. Rusin and M. Minarovjech) from Slovakia. I was the main person to host them at ISAS for a Yohkoh seminar. After that, we discussed the 1999 solar eclipse images taken by them. Since they were interested in the SXT images taken around the eclipse we decided to collaborate with them in the analysis of their observations. Plans for December 2000 and January 2001: To become proficient in the SXT_CO tasks, I need to improve my skill in handling the HTML language as well as in writing good English. Having written my first nugget on coronal holes, I intend to begin a more detailed analysis of large-scale coronal structures and their evolution. Page 16 ------------------------------------------------------------------------------- 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 December 2000 November 2000 |------------------------------- | 6. PERFORMING ORG | CODE: O/L9-41 -----------------------------------------------|------------------------------- 7. AUTHOR(S) | 8. PERFORMING ORGANIZA- T. R. Metcalf | TION REPORT NO: F. M. Friedlaender | |------------------------------- -----------------------------------------------|10. WORK UNIT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS | Lockheed Martin Missiles and Space |------------------------------- Advanced Technology Center, O/L9-41, B/252 |11. CONTRACT OR GRANT NO. 3251 Hanover Street, Palo Alto Ca. 94304 | NAS8 - 00119 -----------------------------------------------|------------------------------- 12. SPONSORING AGENCY NAME AND ADDRESS |13. TYPE OF REPORT AND Marshall Space Flight Center (Explorer Program)| PERIOD COVERED Huntsville Alabama 35812 | Progress report for the month Contact: Larry Hill | of November 2000 |------------------------------- |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 | 16 | ------------------------|------------------------|-----------------|-----------