Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-00119) (for January 2001) 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 The new year and new administration provide additional opportunities for explaining the value of our mission. It is also the year of the senior review requiring us to succinctly make the case for continued support. The instrument is in good condition and the staff is in good health and prepared to face the new millennium with vigor. SOLAR ACTIVITY Yohkoh operations resumed at KSC on 4 Jan after the new year (century) holidays. The GOES X-ray background level stayed around B8 with several C-class flares. An active region coming from the north east limb was the brightest. A C4.5 flare occurred at 09 UT on 4 Jan and was well observed with Yohkoh from the pre-flare phase through after the peak. In mid-January, the GOES X-ray background level stayed around B8 with many C class flares. Two M-class flares occurred. These are as follows: M1.8: 9-Jan-01 6:45UT in NOAA9306 M3.5: 10-Jan-01 10:12UT in NOAA9302. A C5.9 flare and a CME occurred on 10-Jan-01 at 00UT also from NOAA 9302. Later in the month, the GOES X-ray background level stayed around B7 - 8, as it did earlier in the month. Three M-class flares occurred; one on 19-Jan, which was luckily during Yohkoh daytime outside SAA, and two on 20-Jan, the peaks of which were also observed from Yohkoh. There was a burst of activity at the end of the month with many GOES C-class flares and 3 M-class flares. A nice cusped arcade was seen on Page 2 the northeast limb on 26-27 Jan. During the 25-27th, some gorgeous mass ejections were seen in the SoHO/LASCO coronagraph data, and one can find some corresponding phenomena in our full-frame X-ray images. CAMPAIGNS We carried out no cooperative observing programs during January, but have a target-of-opportunity (TOO) search for sigmoid structures under way since Dec. 9. SCIENCE The SXT team held a workshop to study the deconvolution of the SXT point spread function and scattering wings. The workshop was held at the Institute for Astronomy, U. Hawaii on 18-19 January 2001. Participants included Takeo Kosugi, Hiro Hara, Piet Martens, Hugh Hudson, David McKenzie, Loren Acton, Tom Metcalf, Phil Shirts, Leon vanSpeybroeck, Barry LaBonte, and Jing Li. The workshop was considered very successful. It was agreed that cleaning of the half-resolution, full-frame, SXT Science Composite (SSC) images was a different problem than attempts to deconvolve the point spread function (PSF) from full-resolution, partial-frame, flare images. In the former case the primary objective is correcting the effects of x-ray scatter and the properties of the core of the PSF is not important. In the latter (flare) case correction for the core and near wings of the PSF is important. Scattering Wings: McKenzie, Metcalf and Shirts performed experiments using FFT and MEM techniques to clean an SSC with a PSF comprising a delta-function core and scattering wings which fall of as the square of the distance form the scattering source. Initial efforts were encouraging. Acton verified the slope of the SXT scattering wings in sxt_psf.pro (-1.89) by normalizing the PSF to one location in a 12/26/91 starburst image and subtracting that PSF from the starburst. The correction was satisfactory. Residual noise in the corrected image centered on 0. Flare correction: Hudson examined recent data from the flare scattering table experiment that traced the shadow of the entrance-filter "spider" to near the core of the flare. Kosugi and Hara were successful in their attempts to clean a flare image through the use of FFT with "bandwidth expansion" (rebinning to finer pixels by a factor of 2) employing a Gaussian weighted Moffat function for the core PSF. The elimination of the broad wings of the Moffat function stabilized the deconvolution. Other: Martens investigated blind iterative deconvolution (BID) and concluded that this technique, which yields both a cleaned image and a PSF, is worth pursuing as a means of better determining the SXT PSF with partial-frame images. LaBonte demonstrated that when placing the FFI into a larger array to do an FFT it is not necessary to take into account the scattering into the extended image -- zeroes are OK. Also, Page 3 when deconvolving half-resolution FFIs it is not necessary to expand the bandwidth by rebinning to more pixels. In other science related news, Canfield worked with MSU Postdoctoral Fellow Bob Leamon on the interplanetary signatures of eruptions that occurred in Yohkoh X-ray sigmoids. The preliminary finding is that the properties of magnetic clouds associated with sigmoids are quite atypical of magnetic clouds as a whole. He worked with undergrad Trish Jibben and Dana Longcope to finish the first draft of a paper on the comparison of SXT jet / MCCD surge events to maps of twist in photospheric magnetic fields, inferred from Mees vector magnetograms. We find that the twisting motion typical of surges is very well correlated with the motion expected from the relaxation of twist stored in photospheric fields. Canfield worked with undergrad Angela Colman to finish the first draft of a paper on moving blue-shift events in the Mees data, based on Wuelser's list of the best-observed Mees/Yohkoh flares. That work has revealed striking differences between the frequency of moving blue-shift events before and after eruptive flares. Finally, he worked with Alex Pevtsov on the hemispheric distribution of sigmoids and their comparison to the previous solar cycle. They find that the hemispheric helicity distribution for cycle 23 is the same as that for cycle 23, lending support to the Sigma-effect model of Longcope, Fisher, and Pevtsov. Hudson continued work with Fletcher, dealing with the Bastille Day flare ribbons. They point out the occurrence of a nearly homologous event at the same solar location, but almost two rotations later and suggest that some large-scale organizing principle imposed by the corona itself, rather than emerging flux, somehow dictates the flare morphology for large events of this sort. PUBLICATIONS Submitted: E. W. Cliver and H. S. Hudson, "CMEs: How do the puzzle pieces fit together?", submitted to the S-RAMP conference proceedings January, 2001 B. De Pontieu, P. C. H. Martens, and H. S. Hudson, "Chromospheric damping of Alfven waves", submitted to ApJ January, 2001 I.M. Chertok, H.S. Hudson, E.I. Mogilevsky, V.N. Obridko, and N.S. Shilova, "Solar disappearing filament inside a coronal hole and associated large-scale activity," submitted to ApJ January, 2001 Accepted: The Physical Nature of the Loop-top X-ray Sources in the Gradual Phase of Solar Flares by Nariaki V. Nitta, Jun Sato, and Hugh S. Hudson, accepted for publication in ApJ. Page 4 "Large Doppler Shifts in X-ray Plasma: An Explosive Start to Coronal Mass Ejection", by D. Innes, W. Curdt, R. Schwenn, S. Solanki, G. Stenborg, and D. McKenzie Pevtsov, A. A., Canfield, R. C., and Latushko, S: ``Hemispheric Helicity Trend for Solar Cycle 23'', ApJ Letters, in press, 2001. H. S. Hudson and E. W. Cliver, "Observing coronal mass ejections without coronagraphs", accepted by J. G. R. December, 2000 H. S. Hudson and D. E. McKenzie, "Hard X-rays from slow flares", accepted by EPS January, 2001 "Chromospheric Heating in the late-phase of Two-ribbon flares", Czaykowska, Alexander and De Pontieu, accepted. "Evidence for the flare trigger site and 3D reconnection in multi-wavelength observations of a solar flare", by Fletcher, Metcalf, Alexander, Ryder and Brown accepted Sturrock, P.A., Weber, M., Wheatland, M.S., & Wolfson, R. 2000, Metastable Magnetic Configurations and their Significance for Coronal Mass Ejections. Ap.J., in press. Published: PUBLIC USE OF SXT IMAGES Alexander defined the dates and format for Solar Week 2001 which will run April 23-27 to coordinate with Sun-Earth Day (April 27). 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. he WEB access statistics in January were 211095 accesses and 8690 Mbytes transferred for the SXT website and 270035 accesses and 5443 Mbytes transferred for the YPOP website. YOHKOH OPERATIONS AND HEALTH Yohkoh and the SXT continue to function very well. Yohkoh survived another long holiday recess. After the operations holiday, SXT came up with an SEU on the first orbit, but the tohbans flawlessly fixed everything and the Sun, as usual, looks beautiful. SXT experienced a normal level of Single Event Upset (SEU) events during the month: Page 5 SXT Error 04-Jan-01 Pass 1: 010104-0412 Recovered in the second pass Night Command Error 15-Jan-01 Pass 1: 010115-0103 Recovered in the second pass Bit Map Error 18-Jan-01 Pass 2: 010118-0206 Recovered in the same pass Bit Map Error 26-Jan-01 Pass 1: 010126-1239 Recovered in the same pass Bit Map Error 28-Jan-01 Pass 1: 010128-1239 Recovered in the same pass Page 6 DATA FLOW Month Full Frame Images Observing Region Images Received Lost Received Lost Loss % QT FL Tot Thru Nov-98 584732 216829 2348768 542615 2891383 1047473 26.38 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 6348 1524 23309 6629 29938 7916 20.91 Nov-00 6525 1639 20087 10318 30405 6972 18.65 Dec-00 6572 1918 20664 5422 26086 8070 23.63 Total 750542 266314 2938610 847218 3785828 1294802 25.49 Number of Full Frame Images Received: 750542 Number of Observing Region Images Received: 3785828 Total: 4536370 Approximate Number of Shutter Moves/CCD Readouts: 7715359 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 7 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 (%) Dec-98 57.90 1027.0 222113 32689 23.8 N/A Jan-99 58.70 1056.9 227320 37869 23.1 N/A Feb-99 58.65 1055.1 224924 37889 23.2 N/A Mar-99 59.26 1078.1 227900 43051 21.7 N/A Apr-99 58.81 1060.9 225818 38724 23.8 / 1 21.4 N/A May-99 58.78 1059.8 225791 38435 21.6 N/A Jun-99 59.40 1083.0 230091 42440 22.0 N/A Jul-99 59.97 1104.5 231281 47075 23.8 / 1 20.6 N/A Aug-99 59.39 1083.0 229319 43067 21.7 N/A Sep-99 60.15 1111.2 231820 49868 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 61.11 1147.3 234385 57376 22.5 / 2 25.3 N/A Jan-00 60.27 1115.9 233820 50214 23.4 N/A Feb-00 60.88 1138.5 234925 56305 23.8 N/A Mar-00 60.71 1132.5 234146 54564 22.9 N/A Apr-00 61.10 1147.0 235252 58348 22.2 N/A May-00 61.01 1143.6 234463 57246 21.2 N/A Jun-00 61.35 1156.3 235998 60373 22.8 N/A Jul-00 61.89 1176.7 237949 66181 19.3 N/A Aug-00 61.26 1153.1 236088 59872 56.9 / 2 21.7 N/A Sep-00 61.08 1146.2 235644 58449 22.1 N/A Oct-00 61.65 1167.6 237518 63524 23.1 N/A Nov-00 60.95 1141.4 235715 56905 24.2 N/A Dec-00 61.48 1161.3 237127 62618 23.8 / 2 21.8 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 8 PERSONNEL TRAVEL SXT Foreign Travel between 1-JAN-01 and 31-JAN-01 BARTUS 1-JAN-01 * 31-JAN-01 * 31 (total of 31 days) HUDSON 1-JAN-01 * 16-JAN-01 16 (total of 16 days) TAKEDA 6-JAN-01 31-JAN-01 * 26 (total of 26 days) ---------------------------------------------------------------- Grand Total of 73 days for 3 people NOTE: The "*" signifies travel that actually ends after 31-JAN-01 SXT Foreign Travel between 1-FEB-01 and 28-FEB-01 BARTUS 1-FEB-01 * 28-FEB-01 * 28 (total of 28 days) HUDSON 5-FEB-01 16-FEB-01 12 28-FEB-01 28-FEB-01 * 1 (total of 13 days) NITTA 18-FEB-01 28-FEB-01 * 11 (total of 11 days) TAKEDA 1-FEB-01 * 28-FEB-01 * 28 (total of 28 days) ---------------------------------------------------------------- Grand Total of 80 days for 4 people NOTE: The "*" signifies travel that actually ends after 28-FEB-01 Respectfully submitted, Thomas R. Metcalf Frank Friedlaender Page 9 =================================================================== Montana State Univ Activity Report for December 2000 - January 2001 =================================================================== (L. Acton) INTRODUCTION The MSU group carried out SXT operations, data analysis, graduate and undergraduate research, participated in meetings, and performed outreach activities. The highlight of this reporting period was the agreement by ISAS to modify the long standing policy for a one-year delay in the public release of Yohkoh data. Hereafter there will be no restriction on the scientific use of Yohkoh data. YOHKOH AND SXT OPERATIONS Yohkoh health remains good and operations normal. MSU did not participate in operations at ISAS during the reporting period. Normal experiment monitoring was continued from MSU via the Internet. Dr. Brian Handy has accepted another position and vacated his SXT post-doctoral position as MSU. The SXT chief-observer/scientist position has been advertised and the final selection to fill this post is underway. Canfield served as Yohkoh Duty Scientist at Mees Solar Observatory the week of Dec 19 - 26. MEETINGS An informal workshop was held 18-19 January at the Univ. of Hawaii Institute for Astronomy on SXT image deconvolution. Removal of the effect of SXT point spread function and scattering wings from SXT images is important for flare temperature analysis and for accurate photometry of the faint corona and coronal holes in SXT full frame images. The workshop was quite successful. A fast Fourier transfer (FFT) scheme for cleaning flare images, utilizing a modified point-spread function, was worked out and tested by Hara and Kosugi. Likewise, a similar approach appears to be feasible for cleaning the effects of x-ray scattering wings from full-frame images. Martens is looking to the use of blind iterative deconvolution as a means to gain information on the in-flight point spread function for the different SXT analysis filters. A summary of the workshop may be found at http://solar.physics.montana.edu/SXT/Decon2001/ We anticipate that SolarSoft codes to implement these image cleaning procedures will be completed during the next reporting period. Richard Canfield, Dana Longcope and grad student Brian Welsch Page 10 participated in the winter AGU meeting in San Francisco. RESEARCH Acton continues to work with Lemen, Freeland and Metcalf on the SXT Science Composite movie. This mission-long archive of full frame images will be in floating point and include the best possible corrections. He is also working with A. Pevtsov, G. Fisher, and D. Longcope on study a correlation between magnetic flux and X-ray luminosity. Martens and collaborators completed and submitted to ApJ our paper: "Chromospheric Damping of Alfven Waves", which makes a good case for damping in the chromosphere and temperature minimum region of coronal waves. He worked with C. Kankelborg on the paper "The Relationship Between Flux Tube Cross-Section and Curvature", and found some counter-examples to their general results -- work continues on this. Canfield worked with MSU Postdoctoral Fellow Bob Leamon on the interplanetary signatures of eruptions that occurred in Yohkoh X-ray sigmoids. The preliminary finding is that the properties of magnetic clouds associated with sigmoids are quite atypical of magnetic clouds as a whole. With Dana Longcope and undergrad Trish Jibben he has discovered find that the twisting motion typical of surges is very well correlated with the motion expected from the relaxation of twist stored in photospheric fields. With grad student Angela Colman he finds striking differences between the frequency of moving blue-shift events in H-alpha before and after eruptive flares. He worked with MSU undergrad Yuriko Yamazaki to make CDs of Mees coronagraph prominence eruptions for comparison with SXT events. The data are finished back to roughly 1995. These CDs are being sent to Tonooka san at Chiba University, for comparison with SXT images. Finally, he worked with Alex Pevtsov on the hemispheric distribution of sigmoids and their comparison to the previous solar cycle. They find that the hemispheric helicity distribution for cycle 23 is the same as that for cycle 23, lending support to the Sigma-effect model of Longcope, Fisher, and Pevtsov. McKenzie worked with data for JOP104, from the flare event of 26-Oct-00. SUMER (D. Innes) observations includes Doppler shifts at the time that SXT suggests X-ray ejecta crossing the SUMER slit. He also recalculated energies of active region transient brightenings which were observed as part of JOP080 for presentation in a paper by Berghmans et al. SERVICE AND OUTREACH Mission-long x-ray irradiance data have been supplied to K. B. Ramesh of the Indian Institute of Astrophysics for research involving comparison with other measures of solar spectral irradiance. McKenzie completed development of the improved SXT/Yohkoh website (http://solar.physics.montana.edu/SXT/) and continued maintenance work on it and the ever-popular Yohkoh Public Outreach Project site. Page 11 Canfield reformatted the SXT Chief Observer's weekly reports at http://solar.physics.montana.edu/nuggets/ and mirror sites at Lockheed, ISAS, and MSSL. PUBLICATIONS: Papers Accepted: ---------------- "Large Doppler Shifts in X-ray Plasma: An Explosive Start to Coronal Mass Ejection", by D. Innes, W. Curdt, R. Schwenn, S. Solanki, G. Stenborg, and D. McKenzie, was accepted by ApJL. This paper grew out of JOP104 observations from 09-May-99. "Hemispheric Helicity Trend for Solar Cycle 23" by A. A. Pevtsov, R. C. Canfield and S. Latushko, ApJ Letters, in press, 2001. Papers Submitted: ----------------- "Chromospheric Damping of Alfven Waves" by B. DePontieu, P. Martens and H. Hudson, submitted to ApJ. Answered referee's comments for the paper "Active Region Transient Brightenings: A Simultaneous View by TRACE, EIT, and SXT", by D. Berghmans, D. McKenzie, and F. Clette: resubmitted to Astronomy & Astrophysics. Submitted revised paper to ApJ on "Soft X-ray luminosity and photospheric magnetic field in quiet Sun" by A. Pevtsov and L. Acton. Talks Given: ------------ "S Marks the Spot", USAF Science Advisory Board meeting, Hanscom Air Force Base, MA Nov 30 - Dec 1, 2001. =============================================================== Univ of Hawaii Activity Report for December 2000 - January 2001 =============================================================== (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. Page 12 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 average during these months. Observations were obtained on 100% of all scheduled days in December and 76% of scheduled days in January. Total coverage was limited by the number of holidays and problems with instruments. During this interval, the IVM was used to record magnetograms in the Na D line, formed near the temperature minimum, where the magnetic field is more nearly force-free, as part of a study with T. Metcalf (LMSAL). A miniworkshop was held at the IfA during January 18 and 19 on the subject of deconvolution of SXT images. A dozen workers studied various issues relating to the measurement and removal of the SXT point-spread-function. Treatment of the lower resolution FFI movie and the full resolution PFI data were both considered. The results of this work should appear in improved codes for SXT data analysis. LaBonte is working with D. Rust (JHUAPL) on a study of AR8844, an emerging flux region that was well observed by Mees and SXT as part of the campaign connected with the long duration balloon flight of the Flare Genesis telescope. The first paper from this study will be an analysis of the magnetic structure as flux emerges and forms into sunspots. Li is preparing a paper using SXT data to reveal the differing rotation rates of coronal streamers observed over the solar poles. The range of rotation rates is consistent with the range of latitudes over which the streamers are situated. This is a clear contrast to the general perception that the corona rotates more rigidly than the surface. ============================================================== Stanford Univ Activity Report for December 2000 - January 2001 ============================================================== (P. Sturrock) As mentioned in the last report, Peter Sturrock and Mark Weber are beginning to compare SXT data with neutrino data, with the goal of confirming or disproving early claims of association between neutrino flux measurements and various indices of solar activity, including coronal brightness. Some time ago, Massetti and Storini [Ap.J. 472, 827, 1996] compared the Homestake neutri- no measurements and coronal green-line measurements. We can best evaluate that claim by using different neutrino data and dif- ferent coronal data. Accordingly we are working with neutrino measurements produced by the GALLEX and GNO experiments, and X- ray flux measurements from SXT. As part of the work for his dissertation, Mark has already compiled time series for the daily Page 13 mean SXT flux for the nine latitude bins, 60S, 45S,..., 45N, 60N. Massetti and Storini carried out statistical correlation tests. We have decided to take a different approach here, too. Almost any solar index (and certainly coronal emission) displays strong rotational modulation. From earlier investigations, we have found evidence that the neutrino flux also is modulated by solar rota- tion. We have therefore conjectured that the correlation, if real, may be due simply to the fact that the two variables (neu- trino flux and X-ray flux) are both subject to similar periodic modulations. As a test of this hypothesis, we have formed the spectral corre- lation function, namely the geometric mean of the powers of the neutrino spectrum and of the SXT spectrum derived from the equa- torial data. We select the equatorial data since the beam of neu- trinos detected at Earth covers only a small range of heliograph- ic latitude. We have focused our attention on the profile of ro- tation rates for the equatorial section of the convection zone, as determined by Schou et al. [Ap.J. 505, 390, 1998] from MDI data. By integrating over radius, we obtain an overall frequency profile for the convection zone. We then convolve this with the neutrino spectrum. In order to obtain a significance estimate of the resulting statistic, we repeat this process many times on "shuffled" neutrino data, for which neutrino measurements are randomly re-assigned among runs. From our preliminary calcula- tions, it seems that there is indeed a correlation between the GALLEX-GNO measurements and the SXT measurements, with better than 1% significance. We are also beginning to analyze the rotational modulation of the solar X-ray flux independently of its possible relationship to neutrino data. By convolving the power spectrum of the X-ray flux with the MDI estimates of the Sun's internal rotation as a function of radius and latitude, we may display on a cross- sectional map of the solar interior a statistic indicating the probable origin of time-variation of the X-ray flux. When we ex- amine SXT data in this way, we find one internal locus for X-ray flux detected at 0, +/- 15 and +/- 30 degrees latitude, and we find a second locus for X-ray flux detected at +/- 60 degrees la- titude. Both loci show up in the analysis of X-ray flux detected at +/- 45 degrees latitude. We do not see a gradual shift such as one would find from a similar analysis of sunspot data, for in- stance. These leads us to question whether the X-ray flux may be modulated by two distinct regions of sub-photospheric magnetic field. This could perhaps by investigated by extending the model of DeVore and Sheeley [Solar Phys. 108, 47, 1987] to include the diffusion of magnetic flux in radius as well as in latitude and longitude. Page 14 Mark is writing up his findings from his investigation of CME en- ergetics and the Aly-Sturrock theorem. He has found a family of force-free field (FFF) solutions for flux-tubes belted about the solar equator, with energies greater than that of the open dipole configuration. Because the fields involve force-balance between the flux systems, such solutions suggest a model for metastable magnetic field configurations which contain sufficent energy to drive coronal mass ejections (CMEs). The solutions are found nu- merically, but an analytic model is sufficient to predict the re- gion of parameter space which will produce the desired force- balanced solutions. It is discovered that the energy content of the flux-tube is more sensitive to the radius of the tube than to the amount of twist. The minimum practical radius for a global flux-tube with sufficient energy to open the overlying arcade is about 0.2 solar radii. Two other topics that Peter and Mark have developed an interest in are X-ray jets and SXT bright loop-top kernels. They are con- sidering models which may contribute to previous work done on these subjects. PUBLICATIONS Sturrock, P.A., Weber, M., Wheatland, M.S., & Wolfson, R. 2000, Metastable Magnetic Configurations and their Significance for Coronal Mass Ejections. Ap.J., in press. ============================================================================= Solar Physics Research Corp. Activity Report for December 2000 - January 2001 ============================================================================= (Karen L. Harvey and Hugh S. Hudson) KAREN L. HARVEY: Activities for December and January: (1) Continuing with the analysis of the 18 December 1998 HAO/CHIP He I 10830 data to measure the magnetic flux as a function of time within an area bounded by the two flare ribbons and the polarity inversion separating them and within the associated transient coronal holes. At this time, the flux determination within the two coronal holes has been measured, and shows that assuming the fields are radial that the western coronal holes has about twice a much flux in it than the eastern hole. The areas as a function of time are comparable. The change in magnetic flux increases with time and in a similar fashion as the area. The increase is rapid initially then levels off about one hour after the start of this event. As mentioned in previous reports, the objective of this study is to Page 15 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). The MDI magnetograms taken during this time interval are also being requested as a check on the magnetic flux determination. The coronal hole boundaries will be directly applied to the MDI data to extract this information. (2) Continuing with 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. Plans for February and March 2001: Continued analysis and study of (1) 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; (2) the association of coronal holes observed in He I 10830 spectroheliograms and the SXT full-frame images; (3) returning to the analysis of XBP data and their association with magnetic bipoles. HUGH S. HUDSON Activities for December and January Attended the HESSI science workshop in Berkeley, the AGU meeting in San Francisco, and the CDAW on SXT image deconvolution in Honolulu. Presentations from each are on the Web, links to my "talks" page http://isass1.solar.isas.ac.jp/~hudson/talks. In brief these items are: i) For HESSI I tried to imagine what the early important results would be. Who knows, really, but my hunch is that we will see remarkably new things in the "firm" X-ray energy band, which bridges the soft and hard bands. HESSI should really be good there because of resolution and because of its innovative shutter operation. ii) The AGU talk, and the subject of continuing work with Fletcher, dealt with the Bastille Day flare ribbons. The presentation pointed out the occurrence of a nearly homologous event at the same solar location, but almost two rotations later - the suggestion here is that some large-scale organizing principle imposed by the corona itself, rather than emerging flux, somehow dictates the flare morphology for large events of this sort. iii) For the CDAW I checked the new database from the special scattering flare tables, which we ran for the latter part of 2000, and found dozens of events including some bright compact ones. For one of the latter, the quite interesting event of Sep. 30, 2000, I confirmed the presence of Page 16 large azimuthal variations in scattering amplitude and tried to develop ways to normalize the scattering wings without doing a full deconvolution. Otherwise I continued to work on CMEs and flares by helping Ed Cliver write an innovative review for S-RAMP. Plans for February and March 2001: 1. Continue to work on large-scale waves with Joe Khan; great progress is being made, I think. 2. Prepare for studies of coronal hole boundaries. 3. Participate in ISSI workshop on fine structure. 4. Work further with the flare database on SXT mirror scattering, as a continuation of the CDAW held in January (see a forthcoming nugget and http://solar.physics.montana.edu/SXT/Decon2001/). 5. HESSI. PUBLICATIONS Papers Accepted: H. S. Hudson and E. W. Cliver, "Observing coronal mass ejections without coronagraphs", accepted by JGR December, 2000 H. S. Hudson and D. E. McKenzie, "Hard X-rays from slow flares", accepted by EPS January, 2001 Papers submitted: E. W. Cliver and H. S. Hudson, "CMEs: How do the puzzle pieces fit together?", submitted to the S-RAMP conference proceedings January, 2001 B. De Pontieu, P. C. H. Martens, and H. S. Hudson, "Chromospheric damping of Alfven waves", submitted to ApJ January, 2001 I.M. Chertok, H.S. Hudson, E.I. Mogilevsky, V.N. Obridko, and N.S. Shilova, "Solar disappearing filament inside a coronal hole and associated large-scale activity," submitted to ApJ January, 2001 TAKEDA AKI: Activities for December and January: Page 17 In 11-12 December, I experienced one of the major special operations, CCD bakeout, for the first time since I started to work. I learned how to prepare, monitor the status, and resume normal operation. On 18 December, Yohkoh detected small flares and got into unnecessary flare-modes. In order to examine this anomalous behavior, I made a study on the flare detecting system used in Yohkoh. It required consulting the Yohkoh manual and contacting some core persons of Yohkoh team for confirmation. The results can be found in the following document: http://isass1.solar.isas.ac.jp/sxt_co/flare-trigger-level.txt. I attended a Japanese domestic meeting on space weather during 15-16, January held in the Shizuoka prefecture. I did not give a talk, but I had a good time discussing with people about studying different field, especially on terrestrial climate and its long-term variation. Last of all, I worked for 5 full- and 2 half-weeks as a SXT Chief Observer, and for 1 week as a Yohkoh Operator at ISAS, as shown in the list below. week 49 (27-Nov through 3-Dec) : SXT_CO week 50 (4-Dec through 10-Dec) : Yohkoh Operator at SSOC week 51 (11-Dec through 17-Dec): SXT_CO week 52 (18-Dec through 24-Dec): SXT_CO week 53 (25-Dec through 28-Dec): SXT_CO (shared with Hugh Hudson) week 01 (4-Jan through 7-Jan): (new year vacation) week 02 (8-Jan through 14-Jan): own research week 03 (15-Jan through 21-Jan): SXT_CO (shared with Hugh Hudson) week 04 (22-Jan through 28-Jan): SXT_CO week 05 (29-Jan through 4-Feb): SXT_CO Plans for February and March: I am used to most of the daily operations of SXT. As I wrote in previous reports, however, I did not have my own SXT research yet started. I worked on my previous topic, the analysis of the total solar eclipse images, because I was required recently to submit a report for that. Looking at SXT images every day, I still have much interest in a large-scale coronal structures. I hope to make some progress on this field as soon as possible. JANOS BARTUS My first task was to get acquainted with the SXT computer system and environment with the kind supervision of Greg Slater. The ambitious plan was that a new linux system had to be set up, which would take over the tasks from the present servers, but would also do much more. To date I've managed to set up the main server and software etc., starting just from the basic hardware. This required extensive software installation, system configuration and testing. Page 18 In setting up the system my main objectives were to - set up a stable system - make it as similar to the original server as possible so that the replacement would be transparent and relatively "painless" for the users - enhance and update the security - ensure the continuous update Now the system has just been put into test mode, and the primary users have been asked to check its capabilities using various services and report any problems they encounter. Plans for February and March: I will continue the work with the system setup. Soon the server exchange will be done. This is going to require me to continuously monitor and update the system and to respond quickly to user's requests, correcting errors, etc. One of my main task is to set up a "high availability" system where the secondary server mirrors the primary server and would take over the its services if any fatal error would happen to the main server. =========================================================================== University of California Activity Report for December 2000 - January 2001 =========================================================================== (G. Fisher) Griffiths and Fisher (UCB) have continued their collaboration with Falconer (UAH, MSFC) and Metcalf (Lockheed) in their investigation of sheared neutral line lengths and their relationship to coronal heating. We have written a new sheared neutral line length algorithm based on the use of the idl contour routine, and done detailed comparisons with Falconer's original algorithm. The two methods agree well, and in addition the new method removes a small bias in the neutral line length that can occur in Falconer's method when the neutral line is inclined at angles of roughly 45 degrees to the horizontal direction. We have analyzed the dependence of X-ray luminosity as a function of sheared neutral line length, and have confirmed Falconer's conclusion that it is correlated with the total X-ray output of an active region. On the other hand, we still find that the total unsigned magnetic flux is a better predictor of X-ray output, and that the correlation of sheared neutral line length with X-rays can be explained by the correlation of sheared neutral line length with magnetic flux. The investigation is continuing. Johns-Krull (UCB) is analyzing H-alpha linear polarization measurements from BBSO, allegedly a signature of proton beams, and comparing the results with GOES, SXT, and HXT flare observations. Thus far, no clear Page 19 signature of linear polarization has been seen. Page 20 ------------------------------------------------------------------------------- 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 February 2001 January 2001 |------------------------------- | 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 January 2001 |------------------------------- |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 | 20 | ------------------------|------------------------|-----------------|-----------