HEADNEWS: THE ELECTRONIC NEWSLETTER OF THE
HIGH ENERGY ASTROPHYSICS DIVISION OF THE AAS
||Newsletter No. 76, May 2000
- Notes from the Editor - Paul Hertz
- News from NASA Headquarters - Don Kniffen and Lou Kaluzienski
- NASA's Cosmic Journeys Initiative - Alan Bunner
- Termination of the Compton Gamma Ray Observatory Mission - Neil Gehrels
- The Compton Gamma Ray Observatory: A Commentary - Don Kniffen
- Loss of the Astro-E Observatory - Richard Kelley
- Chandra X-ray Observatory Report - Roger Brissenden
- Chandra Science Highlights - Wallace Tucker
- XMM-Newton Update - Richard Mushotzky
- GLAST Selections Announced - Christopher Wanjek and Lynn Cominsky
- Rossi2000 Meeting Report - Tod Strohmayer
- ROSAT All Sky Survey Data Now Available - Mike Corcoran
- Chandra Fellows Named - Nancy Evans
- History of Nuclear Astrophysics Website - Donald Clayton
- New Translation of Galileo Poem - Giovanni Bignami
- HEAD in the News - Lynn Cominsky
- Gamma Ray Astrophysics 2001 Meeting - Chris Shrader
- Laboratory Astrophysics with Intense Lasers - Adam Frank
- A Letter to the Membership - Elena Aprile, Roger Chevalier, Don Clayton, Kevin Hurley, Mark Leising, Edison Liang, and Stan Woosley
- Editor's Comments - Paul Hertz
- Paul Nandra wins AAS Pierce Prize - Lynn Cominsky
- X-ray Astronomy 2000 Meeting - The LOC
- New Century of X-ray Astronomy Meeting - Hajime Inoue
from the Editor - Paul Hertz, HEAD Secretary-Treasurer, email@example.com, 202-358-0986
This newsletter is available on the HEAD website at http://www.aas.org/head/headnews/headnews.may00.html. The web version is completely hyperlinked and is, in my opinion, much easier to read. I encourage you to check it out.
Beginning with this issue, the HEAD Newsletter is available only electronically (e-mail or on the web); there will no longer be a paper version distributed.
Embarrassingly, I seem to have misplaced some articles for the HEAD newsletter during my recent job change. If you sent me an article for the HEAD Newsletter and it does not appear below, please resend the article and I will publish it in a supplement. My apologies if this happened to you.
An Associated Press (AP) story on May 11 referred to a HEAD sponsored letter writing campaign concerning the Compton Gamma Ray Observatory. This is an error -- HEAD is not sponsoring any letter writing campaign concerning CGRO.
Finally, don't forget to register for the HEAD 2000 Meeting in Honolulu, Hawaii, on November 6-10, 2000. Meeting details may be found at http://www.eurekasci.com/. Registration and travel details are at http://www.confcon.com/; early registration ends on October 6. Abstracts are due August 8 and must be submitted through the AAS at http://www.aas.org/~abstract/abstracts.html.
Back to Top
2. News from NASA Headquarters -
Don Kniffen and Lou Kaluzienski, NASA Headquarters
The instruments and Interdisciplinary Scientists selected for the GLAST mission were announced in February. See the separate article below on the GLAST selections.
Chandra X-ray Observatory -
The Chandra X-ray Observatory continues to perform well. Following the early radiation damage to the ACIS CCD's, there has been no further degradation in performance due to corrective procedure implemented shortly after diagnosis of the problem. Efforts to develop mitigation procedures to regain some of the lost energy resolution appear promising, though great care will be taken before this alternate mode becomes standard, possible requiring a few weeks. The overall efficiency for observations remains high and new operating modes are being implemented to enhance it. Meanwhile, many new results have been released to the public and the Guest Observations are now moving along routinely. See the separate articles below on the Chandra Observatory status and Chandra science highlights.
The NASA Research Announcement for the second cycle of the General Observer Program was released on April 7 and proposals are due June 1. The Announcement may be found at http://spacescience.nasa.gov/ under the link to "Research Opportunities."
Compton Gamma Ray Observatory
Unfortunately, the failure of one of the Compton Gamma Ray Observatory's three gyros has left it one failure away from losing the capability to perform a controlled reentry. According to the criteria established before launch, this requires that the spacecraft be de-orbited in a controlled manner as quickly as possible. The plan is for the CGRO to be de-orbited on June 4, 2000, more than nine years after its launch for a nominal five year mission. A commentary on CGRO appears elsewhere in this newsletter as well as a final status report from the CGRO project scientist.
The science of CGRO has been an outstanding success by any measure and the observatory will continue normal science operations late May when preparation for reentry will begin. Press releases and a NASA Space Science Update have highlighted some of the more significant results in recent months including the first observations of gamma-rays from a solar flare during the current solar maximum and the "Beethoven Burst", the second brightest burst seen by BATSE. Localized by RXTE, the counterpart was observed by Keck II at z=0.7 .
Concerns by Goddard Space Flight Center management that HETE-2 should undergo additional testing prior to shipment to the Kwajalein Range for its launch aboard a Pegasus rocket have resulted in a delay in the previous January 2000 launch date. An independent review conducted since that decision has concluded that the mission is technically ready and that, with some additional testing, sufficient confidence will be gained to allow launch plans to continue without a full Red Team review to which most NASA missions are presently being exposed. It appears that July 20 is the earliest launch date possible at this time though conflicts with the availability of the range could cause further delays
Due to delays in development of the science instruments, ESA has announced a 6 month delay in the launch date for INTEGRAL, now scheduled for April 22, 2002. One of the U.S. contributions to the mission is a Pulse Shape Discriminator (PSD) circuit to reduce the internal beta-decay background of the Spectrometer Instrument (SPI). The PSD flight unit has successfully completed environmental testing and has been delivered to the SPI Principal Investigator for integration into the instrument.
Fiona Harrison is 1999 PECASE recipient -
HEAD member Fiona Harrison has received the prestigious Presidential Early Career Award for Scientists and Engineers (PECASE) for 1999. Only a small number of awards are made annually to recognize outstanding young scientists in the U.S. Harrison received the award for her pioneering efforts in the development of an innovative approach to imaging astrophysical objects in the hard X-ray band. She is Principal Investigator on the High Energy Focussing Telescope (HEFT) project, a balloon-borne instrument for imaging cosmic X-ray sources in the 20-100 keV band. Harrison and four other NASA recipients were honored at NASA Headquarters in early April and received the award at a ceremony at the White House presided over by Dr. Neal Lane, Assistant to the President for Science and Technology and Director of the Office of Science and Technology Policy.
Back to Top
3. NASA's Cosmic Journeys Initiative -
Alan Bunner, NASA Headquarters
For those of you who have heard a little about the "Cosmic Journeys" initiative and may be wondering what's happening, here's an update:
Cosmic Journeys is a proposed program line within the Structure and Evolution of the Universe (SEU) theme at NASA, a parallel to the existing program lines for Mars Surveyor, Discovery, Explorers. The essence of the Cosmic Journeys program rationale is to build upon recent clues that the Universe may soon reveal breakthroughs in our understanding of the physics of the cosmos. It's a coming-together of physics and astrophysics to find new ways of answering fundamental questions of physics: How did the Universe begin? How did the laws of physics crystallize out of the Big Bang? Can we use the Universe as a Laboratory to probe the most extreme gravitational fields? Is general relativity the ultimate theory of gravity? What's the connection between general relativity and quantum physics? Have we discovered the geometry of space-time? Or are there big surprises ahead, in the topology or even the dimensionality of space? Can we look to the extremes of physics that nature has provided for clues to new physics?
Beginning in FY 2002, this proposed program line is part of a proposed NASA/DoE/NSF tri-agency initiative, all designed to explore the inner space/outer space connection, to seek answers to cosmic questions, to seek new physics beyond the standard models of particle physics and cosmology, and to study the extremes of gravity, energy, space, and time. NASA's Cosmic Journeys will take us on a virtual exploration of the nature of black holes, ultimately obtaining a direct image of the event horizon. It will investigate the large scale structure of the Universe to constrain the location, quantity, and nature of dark matter, the fundamental geometry of the universe, and the implications of the cosmological constant. And it will search for and study nature's accelerators and the highest energy processes, approaching those found in the early universe.
Already underway in this theme are MAP, Swift, a U.S. role in Planck Surveyor, and GLAST. If approved, the near-term future will bring ACCESS, LISA, and Constellation-X. Beyond these, the Cosmic Journeys roadmap presents a program plan of space missions that build upon the past with progressive steps towards new understanding and visionary horizons.
This proposed initiative has been presented to NASA Administrator Dan Goldin, who appears enthusiastic and has spoken in support of this frontal attack on the physics of the cosmos. The three agencies, NASA, DoE, and NSF have requested and are supporting a new broad, interdisciplinary National Research Council study of this "connection" area between physics and astronomy. This study, called "Physics of the Universe: From Quarks to the Cosmos," will be complete in January 2001.
If Cosmic Journeys succeeds in getting into the Administration's FY 2002 budget request, we will need your support in making this program line a reality.
The Cosmic Journeys roadmap brochure, a product of the Structure and Evolution of the Universe Subcommittee, is available on request from NASA-Goddard Space Flight Center; send an e-mail to firstname.lastname@example.org. Also, a viewgraph presentation on the tri-agency Connections and Cosmic Journeys may be found at: http://universe.gsfc.nasa.gov/presentations/connections.html.
Back to Top
4. Termination of the Compton Gamma Ray Observatory Mission -
Neil Gehrels, NASA's Goddard Space Flight Center
I am very sorry to report that Compton Gamma ray Observatory mission will be terminated near the end of May 2000. A decision to deorbit the observatory was made in March by NASA Headquarters in response to the failure of one of the on-board gyroscopes in December 1999. Significant pieces of the spacecraft are expected to survive re-entry and would pose a safety threat to populated areas within the latitude range of the orbit path. NASA decided that the safest approach is to re-enter CGRO as soon as possible before another gyro fails. Extensive consideration was given to other options that would have allowed the mission to continue, but it was ultimately concluded that each involved increased risk. Many of us from within the project were disappointed as the mission is still scientifically productive, but recognize the position of NASA management in making this difficult decision. The re-entry will occur on June 3 with science operations terminating on approximately May 27. To all of you who have participated in the CGRO mission, our sincerest thanks for the tremendous science that has resulted.
Back to Top
5. The Compton Gamma Ray Observatory: Commentary -
Don Kniffen, NASA Headquarters
For 9 years now, the Compton Gamma Ray Observatory (CGRO) has been one of NASA's most successful missions. The second of NASA's Great Observatories, CGRO has been the flagship of NASA's gamma-ray astronomy program. Designed for two years on orbit and later given 3 additional years of "extended mission lifetime," CGRO has, by any measure, been an outstanding success.
The scientific return from CGRO has been outstanding. The mission has truly revised and extended our view of the most energetic and dynamic processes in the cosmos in many fundamental ways. Within months of launch it had demonstrated that our conventional view of the elusive cosmic gamma-ray bursts was incorrect. Thought to arise from a population of neutron stars in the Milky Way, the BATSE (Burst and Transient Source Experiment) instrument showed bursts did not emanate from the plane of the Milky Way. Their homogeneous distribution on the sky implied that they must originate in a spherically symmetric volume - either in a vast cloud of objects surrounding the solar system, an extended halo surrounding the Milky Way Galaxy, or from a population of objects distributed at cosmological distances. Subsequent observations from BATSE and other spacecraft have shown conclusively that the cosmological origin is the correct interpretation and that gamma-ray bursts not only extend our capability to understand and probe the fundamental laws of physics, but that they can be used as a unique source of information about the nature of the intervening space.
Each of the other three experiments on CGRO has also made fundamental new discoveries. The EGRET instrument (Energetic Gamma-Ray Experiment Telescope) has revealed that about 70 distant active galaxies are sufficiently bright to be observed; prior to CGRO only one quasar was know to be a gamma-ray source. In light of the immense energies involved this is a truly amazing observation and it adds significant information with which to probe and explain these remote objects in the early Universe. The OSSE (Oriented Scintillation Spectrometer Experiment) and COMPTEL ( COMpton TELescope) instruments have used their good energy resolution to observe for the first time the distribution of antimatter electrons and radioactive debris from prior supernovae throughout the Milky Way. These are fundamentally important observations which have shed considerable light on the very basic questions of how life could develop in a world devoid of anything but the hydrogen and the light elements produced following the big bang. The number of discoveries is too numerous to mention them all.
Unfortunately, in December 1999, one of the three gyros on the Compton Gamma Ray Observatory failed. The gyros are used as references for all of the spacecraft and scientific pointing maneuvers and the loss of one left the Observatory only a single failure away from losing the ability for a controlled re-entry. Because of its large mass, the Level 1 requirements, established prior to launch, identified such an event as a decision trigger point for de-orbiting the spacecraft in a controlled manner. Uncontrolled re-entry of the spacecraft presents a substantial safety issue because many large pieces are expected to survive re-entry into the atmosphere. While there is no imminent danger of another gyro failure, the single point failure is recognized to be a risk because of the age of the systems on the spacecraft. In light of this, and the risk of continued operation of the spacecraft while the reliability of other control modes is tested, the decision has been made to proceed with re-entry to ensure the safe return of this massive spacecraft while it is still possible to do so. This is the safest course of action.
The current Plan is to begin re-entry operations on May 26, 2000. The final descent will occur on June 3. The target area occupies an uninhabited area of the Southeast Pacific, 2500 miles southeast of Hawaii and more than 600 miles from any inhabited land mass. The debris field will be about 26 miles wide and 962 miles long. About 200 pieces are expected to survive re-entry. Most of them are expected to be small, but 30-40 could be as large as 40 pounds. They would impact the surface at speeds of about 200 miles per hour.
Until the re-entry sequence is initiated on May 26, science operations will continue, providing the same high quality data this remarkably reliable mission has produced for 9 years.
Back to Top
6. Loss of the Astro-E Observatory -
Richard Kelley, NASA's Goddard Space Flight Center
It is with great regret that we have to report the loss of the Astro-E observatory shortly after launch on February 10, 2000. Astro-E was to be the latest in a series of collaborative Japanese x-ray missions designed to provide powerful new instruments for x-ray astrophysics. Astro-E featured the high resolution X-ray Spectrometer (XRS) based on the microcalorimeter, four CCD cameras for imaging x-ray spectroscopy (XIS), and a hard x-ray detector system (HXD). These instruments were all coaligned to provide a simultaneous bandpass from 0.3-700 keV. The XRS and the four XIS cameras had separate focusing x-ray optics based on conical-approximation foils with smooth replicated surfaces. Astro-E would have provided the first opportunity to use the comparatively new x-ray microcalorimeter in an observatory. This sensor is based on the thermal detection of individual x-ray photons and has very high energy resolution (~10 eV FWHM) over a large bandwidth with high intrinsic quantum efficiency.
There are many areas of research where Astro-E would have been particularly powerful. These include using the high spectral resolution of the XRS throughout the x-ray band, but especially in the region of the H- and He-like transitions of iron (6-7 keV), and using this resolution to infer the dynamics and physical state of the most extreme regions in the universe, such as clusters of galaxies and the event horizons of accreting black holes. The combined response of the XIS cameras provided exceptional collecting area for imaging spectroscopy over a wider field of view than the XRS. This capability would have allowed mapping of the emission from extended or multiple sources and inferring the physical conditions and abundances from diffuse sources such as SNRs and x-ray clusters of galaxies. The HXD would have been used to probe the non-thermal emission of sources out to almost 700 keV with extreme sensitivity. The specifications of Astro-E were unique and would have complimented the spectroscopic capabilities of Chandra and XMM-Newton by extending high resolution spectroscopy to higher energies with high sensitivity.
The launch failure is still under investigation. The M-V launch vehicle carrying Astro-E developed problems soon after launch. It was immediately apparent that the trajectory was more vertical than required. The second and third stage engines fired properly and tried to compensate for the lower azimuthal velocity, but these were not sufficient to overcome the first stage malfunction, and the vehicle literally fell just short of establishing orbit. The problem was quickly traced to a faulty engine nozzle lining on the first stage of the M-V rocket which subsequently led to damage of the attitude control system. However, it is not yet clear what might have caused the nozzle to fail.
The loss of Astro-E is a major set back for high energy astrophysics. Constellation-X would be the next mission to realize the full potential of high throughput, high resolution imaging x-ray spectroscopy, and beyond this the XEUS mission. In the meantime, there are proposals in the US and Japan to try to recover as much of the Astro-E science as possible, especially while Chandra and XMM-Newton are still active, in order to provide high resolution x-ray spectroscopy over as large a composite bandwidth as possible.
Back to Top
7. Chandra X-ray Observatory Report -
Roger Brissenden, Chandra X-ray Science Center, Smithsonian Astrophysical Observatory
The Chandra X-ray Observatory was launched on the Space Shuttle Columbia on 1999 July 23 and deployed together with its attached Inertial Upper Stage (IUS) 7 hours 16 minutes into the mission. Following two IUS burns, solar array deployment, IUS separation and a series of Integral Propulsion System burns, Chandra reached its final orbit of 139,100 km x 9,700 km altitude with period 63.5 hours on 1999 August 7. The spacecraft and science instrument activation and checkout phase was completed as planned by 1999 October 1. This phase included the excitement of taking the first focus image of the "point source" quasar PKS 0637-752 and discovering that at Chandra's resolution the source showed a clear jet-like structure. The spectacular first light image of the supernova remnant Cas A was taken on 1999 August 19. A two month program of Guaranteed-Time Observer (GTO) observations began on 1999 September 18 followed by the start of combined General Observer (GO)/GTO observations on 1999 November 26.
The spacecraft and ground system performed exceptionally well during the critical early mission phases and into the start of normal science operations. Operational highlights have included nominal power and thermal performance during the first two earth eclipse seasons, the uneventful passage through the Leonid meteor shower on 1999 November 17, and the nominal performance of the spacecraft during the 3 safe mode events. The safemodes resulted from separate ground triggers, and steps have been taken to avoid these triggers in the future. During a safemode, the spacecraft operates on a second set of electronics and hardware (the redundant "B" side) so an important result from safemode entry and recovery is that we now know that all the B-side equipment is functioning well, and that the recovery procedures work properly on-orbit.
Of great concern during September was the detection of increasing degradation in the energy resolution of the front-side illuminated CCDs within the ACIS instrument due to increased Charge Transfer Inefficiency. The likely cause of the increased CTI has been traced to a flux of low-energy charged particles, probably protons, reflected by the mirrors onto ACIS at the focal point during radiation belt passage. Further degradation was halted by moving ACIS out of the focal plane during radiation belt passages. The ACIS engineering team are working hard to develop techniques to mitigate the effects of the degradation, and recent lab and on-orbit test results are very encouraging.
The mission transitioned from a real-time commanding mode to running from stored command loads developed from a mission schedule in late September. The pre-planned mission loads are now developed a week in advance and implement the science schedule. The team has been successful in interrupting the schedule several times to observe high priority Targets Of Opportunity. The approved targets have included a gamma ray burster detected by Beppo-Sax, the supernova in NGC 1637 and most recently Cygnus X-3 during an intense radio burst.
Overall the absolute observing efficiency since the start of GO observations has been approximately 63% compared to a pre-launch goal of 70%. Contributors to the difference include larger than anticipated radiation belts and a conservative pad either side of the belts to ensure no further radiation damage to ACIS. Work is underway by the mission planning team to reduce the times for star acquisition after slews, and to allow observations to begin as early as is practical. These and other efforts in work will contribute to further increasing the observing efficiency. Metrics are also being tracked for the time from observation to user data delivery and for issuing GO grants. The data delivery time has decreased from over a month at the start of the GO phase to approximately 3 weeks, and the grant award time has reduced from 20 days at the start of the GO phase to less 10 days. The CXC is working to reduce these times further.
The NRA for cycle 2 was issued on April 7 with proposals due June 1. The start of Cycle 2 target observations is expected to be in early November 2000.
The May 2000 Chandra Newsletter found at http://asc.harvard.edu/newsletters.html captures the excitement of the first 9 months of the mission and contains articles (with images) of the early science highlights, the Chandra Multi-wavelength Project (ChaMP), and the Chandra Interactive Analysis of Observations (CIAO) analysis software. Additional information about the Chandra mission and the Chandra X-ray Center may be found at http://asc.harvard.edu/.
Back to Top
8. Chandra Science Highlights -
Wallace Tucker, Chandra X-ray Science Center, Smithsonian Astrophysical Observatory
Chandra's first images were dazzling. (see http://chandra.harvard.edu/ for images and accompanying press releases.) Now the science associated with the images is beginning to appear in the literature. There were 47 Chandra-related abstracts presented at the Atlanta AAS meeting, and a search of astro-ph returned 24 papers. Below I give capsule summaries of six published papers to illustrate the breadth of the results.
"Nucleosynthesis and Mixing in Cassiopeia A" (J. Hughes et al. 2000 Ap. J. 528, L109) Chandra first light observations of the Cassiopeia A supernova remnant with ACIS were used to identify sites of iron-rich ejecta produced by explosive silicon burning. Regions containing silicon-rich ejecta from explosive oxygen burning were also observed. The Fe-rich ejecta lie outside the Si-rich material indicating that bulk motions were extensive and energetic enough in Cas A to cause a spatial inversion of a significant portion of the supernova core.
"A Spatially Resolved Plerionic X-ray Nebula around PSR054-69," (E. Gotthelf et al. 2000 Ap. J. 532, L117) The Chandra HRC image of the Crab-like 50 ms pulsar in the Large Magellanic Cloud shows a point like source and nebula that has a morphology and size remarkably similar to the Crab. A patchy outer shell, most likely due to an expanding blast wave, is similar to a shell seen in the radio.
Active Galaxies and AGN
"A Chandra High-Resolution X-ray Image of Centaurus A" (R. Kraft et al, 2000 Ap. J. 531, L9) Chandra HRC observations of Cen A resolved individual knots of emission in the inner jet and diffuse emission between the knots. The nucleus was found to be extended by a few tenths of an arcsecond, and evidence for an X-ray counter jet was seen. Weak X-ray emission from the southwest radio lobe is also seen, and 63 point like galactic sources were detected above a luminosity limit of 1.7 E37 erg/s.
"X-ray Absorption Lines in the Seyfert 1 Galaxy NGC 5548 Discovered with Chandra-LETGS" (J. Kaastra et al. A&A, 354, L83) A high resolution Chandra-LETGS spectrum of NGC 5548 shows strong, narrow absorption lines from highly ionized species (H-like and He-like ions of C, N, O, Ne, Na, Mg, Si, as well as Fe XIV -FeXXI. The lines are blue shifted by a few hundred km/s. Emission from OVIII Ly alpha and the OVII triplet is also seen. The absorbing medium can be modeled by an outflowing, thin and warm shell in photoionization equilibrium.
"Chandra X-ray Detection of the Radio Hot Spots of 3C 295" (D. Harris et al. 2000 Ap. J. 530, L81) An observation of the radio galaxy 3C 295 revealed X-ray emission from the core of the galaxy, from each of the two prominent radio hot spots, and from the previously know cluster gas. Synchrotron-Self Compton models with near-equipartition fields are consistent with the observed X-ray emission from the hot spots.
Hard X-ray Background
"Resolving the Extragalactic Hard X-ray Background" (R. Mushotzky et al. 2000 Nature, 404, 30) Results from a deep (100 ksec) survey of a portion of the Hawaii Deep Survey Field SSAA13 using the ACIS-S instrument aboard Chandra show that the detected hard X-ray sources account for at least 75 percent of the hard (2-10 keV) background in the region surveyed. The mean X-ray spectral energy distribution of these sources is consistent with that of the background. Most of the hard X-ray sources are associated with either the nuclei of otherwise normal bright galaxies or with optically faint sources.
Back to Top
9. XMM-Newton Updated -
Richard Mushotzky, NASA's Goddard Space Flight Center
XMM was launched successfully on December 10, 1999, on the first commercial flight of the Ariane-V rocket and entered its proper orbit. Satellite turn on and commissioning started on Jan 4, 2000. All the instruments are operating properly and calibration activities started on March 10, 2000. The satellite has been renamed XMM-Newton.
First light images and spectra demonstrating some of the capabilities of XMM-Newton from a February 9 press conference are available at http://sci.esa.int/xmm/firstimages/.
Detailed instrument performance is being evaluated and the project scientist, Dr. F. Jansen has summarized it as follows: "Following a review meeting at the Science Operations Centre, Villafranca, Madrid on 8 and 9 March, the Commissioning Phase of the XMM-Newton satellite, the spacecraft and the scientific instruments was declared completed successfully. The spacecraft's performance is well within specification and, in a number of areas, well within the predictions made at the Flight Acceptance Review. The performance of the X-ray optical system, as measured so far, is in line with the expectations from ground testing. The scientific instruments are all fully functional (with the exception of CCD4 of the RGS2). During this phase too, the Ground Systems including stations, the Mission Control Centre (ESOC, Darmstadt) and the Science Operations Centre (Villafranca) were fully exercised and a number of upgrades will be introduced as a matter of course. The next phase, the Calibration and Performance Verification Phase, during which the real scientific performance and capability of the XMM-NEWTON mission will be determined, is now underway."
We will start providing updates to the XMM-Newton status WWW pages on a daily basis shortly, and this will involve providing public access to the XMM-Newton observing log. We will provide public access to a limited number of XMM-Newton Observation Data Files (ODF) as soon as we are sure that these are fully compliant to their specification, and the data analysis software and calibration data are in a state to reliably allow for use of these data sets. Once we will have all this in place we will announce this in another general E-mail to all XMM-Newton users.
The latest information on XMM-Newton can be found at http://xmm.vilspa.esa.es/ and http://sci.esa.int/xmm/.
Back to Top
10. GLAST Selections Announced -
Christopher Wanjek, NASA's Goddard Space Flight Center, and
Lynn Cominsky, Sonoma State University
NASA has selected instruments and interdisciplinary scientists for the Gamma Ray Large Area Space Telescope (GLAST), a key Space Science mission, with a launch anticipated in 2005. GLAST is a next generation observatory designed for making observations of celestial gamma-ray sources in the energy band extending from 20 MeV to more than 300 GeV. The mission follows in the footsteps of CGRO's EGRET instrument, operational from 1991-1999. The Principal Investigator for GLAST's primary scientific instrument, the Large Area Telescope (LAT), is Peter Michelson (Stanford). Charles Meegan (UAH) is PI for GLAST's secondary instrument, the Gamma-ray Burst Monitor (GBM). Jonathan Ormes (NASA/GSFC) is the GLAST Project Scientist. GLAST will be operated as a facility-class observatory with all data placed quickly in the public domain.
The GLAST LAT is being built by a collaboration between astrophysicists and particle physicists. A prime target for the LAT will be the relativistic jets of particles emanating from regions near supermassive black holes. These jets serve as particle accelerators more powerful than anything that could be replicated on Earth. The LAT's science goals are to: understand the mechanisms of particle acceleration in AGNs, pulsars, and SNRs; resolve the unidentified sources and diffuse emission in the gamma-ray sky; determine the high-energy behavior of gamma-ray bursts and transients; and probe dark matter and the early Universe.
These scientific objectives require an instrument with large collecting area, imaging capability over a very large field of view, the ability to measure the energy of the gamma rays over an unprecedented range of energies, and time precision to study transient phenomena characteristic of gamma-ray sources. The instrument must also be designed to separate the rare gamma rays from the much more abundant cosmic rays, and other backgrounds such as gamma rays produced by these cosmic rays slamming into the molecules in the Earth's atmosphere.
The LAT has a field of view about twice as wide (greater than 2.5 steradians) and sensitivity about 50 times that of EGRET at E >100 MeV. The LAT is being built by an international collaboration which includes scientists from Stanford University, the Stanford Linear Accelerator Center, NASA's Goddard Space Flight Center, the U.S. Naval Research Laboratory, the University of California at Santa Cruz, Sonoma State University, the University of Washington, and Texas A&M University-Kingsville in the U.S., the University of Tokyo, ISAS, ICRR, and Hiroshima University in Japan, CEA Saclay and IN2PE in France, INFN, IFC/CNR, and ASI in Italy, and KTH-Stockholm and Stockholm Observatory in Sweden. GLAST LAT funding is being provided by NASA, the Department of Energy, and government agencies in Japan, France, Italy and Sweden. The NASA cost cap for the entire GLAST mission is $326 million.
The LAT has four key components: the Precision Tracker, Calorimeter, Data Acquisition System, and Anticoincidence Detector. The tracker has a four-by-four array of tower modules with interleaved planes of silicon-strip detectors and lead converter sheets. Incoming gamma-rays convert in the lead to an electron/positron pair, which then leaves tracks as the resulting particles shower through the silicon layers and are ultimately deposited in the calorimeter. The tracking system will determine the location of an object in the sky to within 0.5 to 5 arc minutes. The calorimeter consists of an hodoscopic array of Cesium Iodide blocks, instrumented at each end with photodiodes to record the position of the scintillation flash produced by the deposited energy shower. The data acquisition system is the brain behind GLAST, as it makes the initial distinction between background signals and cosmic gamma ray signals, and decides which of the signals should be relayed to the ground. The anticoincidence detector is the first line of defense against the enormous charged particle background. It consists of segmented plastic scintillator tiles, read out by wave-shifting fibers and photo-multiplier tubes. The segmentation is designed to avoid the self-veto problem of EGRET at high energies while still providing high cosmic-ray rejection.
The Gamma-Ray Burst Monitor (GBM) aboard GLAST will provide the broadest energy coverage ever available on a single spacecraft for gamma-ray burst studies. The GBM is being built by an international collaboration of scientists from NASA's Marshall Space Flight Center (MSFC), the University of Alabama, Huntsville (UAH), and the Max Planck Institute for Extraterrestrial Physics (MPE) in Germany. The GBM augments the capabilities of the GLAST Large Area Telescope (LAT) for gamma-ray bursts in two ways. First, the GBM extends the energy range of burst observations from the bottom of the LAT energy range down to ~5 keV. This allows bursts observed with GLAST to be placed into the context of the large database of previous burst observations. Second, the GBM will provide an on-board trigger and approximate location for bursts that lie outside the field of view of the LAT. The spacecraft can then be repointed to observe delayed high-energy emission. The burst monitor capability will complement HETE-2 and Swift, two satellites designed to locate and analyze bursts, to launch in 2000 and 2003 respectively. Together the LAT and GBM provide coverage of the broadest energy range (~5 keV to ~1 TeV) ever achieved on a single spacecraft.
The GBM comprises two sets of detectors. There will be 12 sodium iodide (NaI) scintillators, each 5 inches in diameter, and two bismuth germanate (BGO) detectors, each 5 inches in diameter by 5 inches thick. The NaI detectors cover the lower part of the energy range, from a few keV to about 1 MeV, and provide burst triggers and locations. Burst locations are determined from the relative count rates as is done on BATSE. The field of view is greater than 8 steradians. The BGO detectors cover the energy range of ~150 keV to ~30 MeV, providing good overlap with the NaI at the low end, and with the LAT at the high end.
NASA has also selected four interdisciplinary scientists for the GLAST mission. Stephen Thorsett (University of California, Santa Cruz) will provide the timing data necessary for the study of gamma-ray emitting radio pulsars by the primary instrument as well as an examination of the unique properties of gamma-ray emitting pulsars. Brenda Dingus (University of Wisconsin) will coordinate multi-wavelength studies of transient gamma-ray sources seen with the primary instrument. Charles Dermer (Naval Research Laboratory) will provide the theoretical framework for interpreting the gamma-ray emission from cosmic sources. Martin Pohl (Universitšt Bochum, Germany) will provide careful modeling of the diffuse galactic gamma-ray emission needed for a study of discrete point sources in the Milky Way with the primary instrument.
For more information about GLAST, please see the following web pages. The LAT home page is at http://www-glast.stanford.edu/. The GBM web site is at http://gammaray.msfc.nasa.gov/gbm/. The GLAST outreach web site is at http://www-glast.sonoma.edu/.
Back to Top
11. Rossi2000 Meeting Report -
Tod Strohmayer, NASA's Goddard Space Flight Center (for the RossiXTE Users Group)
From March 22nd through the 24th, 2000, the Rossi X-ray Timing Explorer (RXTE) Users Group and NASA's Goddard Space Flight Center (GSFC) hosted "Rossi2000: Astrophysics with the Rossi X-ray Timing Explorer." This successful meeting drew over 160 researchers, including many HEAD members and international participants, from a broad range of astrophysical disciplines to discuss their latest findings and theories made with or stimulated by RXTE observations. During a busy three-day gathering a total of 68 talks were conducted and an additional 75 contributions were presented as posters. New results presented at the meeting generated some press attention, stemming from four press releases. Among the results that made the news was the first report of a spin-up glitch in an Anomalous X-ray Pulsar (AXP) 1RXS J1708-4009. This result, one of the first confirmed detections of a glitch at other than radio wavelengths was presented by Vicki Kaspi (MIT/McGill University) and her collaborators. Frank Marshall (NASA/GSFC) and his colleagues also reported the occurrence of glitches from PSR J0537-6910, the fastest spinning young pulsar known.
Other results that made the news: Michael Zingale (University of Chicago) and his collaborators presented new hydrodynamic simulations of nuclear detonations on neutron stars, work stimulated in part by RXTE discoveries of millisecond oscillations in X-ray bursts. Their computer simulations reveal surface waves on the hot ash of burned nuclear fuel that move much like ocean waves do on Earth. Samar Safi-Harb (NRC/GSFC) presented evidence for the interaction of jets of energetic particles with the supernova remnant in SS433, indicating that the remnant is being distorted by the action of the jets on the SNR shell, producing strong shock waves and radiating at X-ray energies.
Also at the meeting, Hale Bradt (MIT) gave an informative and humorous presentation in one of the evening sessions featuring a video of four years of the active X-ray sky as viewed with RXTE's All-sky Monitor (ASM). The ASM movie can be viewed at http://heasarc.gsfc.nasa.gov/docs/xte/movies.html. The press releases from Rossi2000 and accompanying images, as well as other SEU press releases, can all be found at http://universe.gsfc.nasa.gov/new/press.html.
Although a conference proceedings volume will not be produced for the meeting, a total of 143 abstracts were received and these are now online and searchable in the ADS abstract database at http://adsabs.harvard.edu/abstract_service.html. Additionally, the abstracts, as well as other details of the Rossi2000 science program, can be viewed online at the Rossi2000 website: http://heasarc.gsfc.nasa.gov/docs/xte/rossi/rossi2000.html.
An ever more important part of mission success and longevity is public awareness of the unique and interesting science which can be done. To this end, an active presence in the popular press and media can be crucial. We would like to encourage all Guest Observers with RXTE science results that they feel might be suitable for press coverage, or who have been contacted by science reporters regarding RXTE observations, to contact Jean Swank (RXTE Project Scientist: email@example.com), Christopher Wanjek (SEU Theme Science Writer at GSFC: firstname.lastname@example.org), and Lynn Cominsky (HEAD press officer: email@example.com). Christopher, Jean, and Lynn can then help to maximize any subsequent media coverage for the benefit of Guest Observers, the RXTE mission, and the high-energy astrophysics community as a whole.
The RXTE Users group would like to express our thanks to all our colleagues who made scientific or logistical (or both) contributions toward a very successful Rossi2000 meeting. Thank you!
Back to Top
12. ROSAT All Sky Survey Data Now Available -
Mike Corcoran, NASA's Goddard Space Flight Center
In March 2000 the Max-Planck-Institut fuer extraterrestrische Physik released the ROSAT All Sky Survey (RASS) data to the general astronomical community. There are 1378 RASS fields, each 6.4 degrees by 6.4 degrees, covering the whole sky. Neighboring fields are overlapping by at least 0.23 degrees. Each field can be identified by an equatorial latitude zone number (running from 1 to 33) and an equatorial longitude segment number (running from 1 to 64, depending on the zone number). There are 1378 directories in the ROSAT Data Archive each containing 10 standard FITS files including images and photon events. In the US, the RASS data can be accessed from the HEASARC archive at ftp://legacy.gsfc.nasa.gov/rosat/data/pspc/processed_data/rass/.
The names of the data directories have been chosen to match ROSAT pointed archival data. For each dataset a 6-digit number (ROR number) has been assigned. The ROR number consists of '93' as the first two digits ('9' for the ROR category 'other and survey data','3' stands for the third RASS processing), digits 3 and 4 correspond to the zone number, 5 and 6 to the segment number. RASS FITS data files start with the 2 characters "rs" to indicate survey data. Users should see http://www.xray.mpe.mpg.de/cgi-bin/rosat-survey/ for more information about the naming convention, sky zone definition, and for quick-look data products.
Back to Top
13. Chandra Fellows Named -
Nancy Evans, Chandra X-ray Science Center, Smithsonian Astrophysical Observatory
Five scientists have been chosen as Fellows of the third annual Chandra X-ray Observatory Postdoctoral Fellowship Program. The fellowships are open to recent astronomy and astrophysics graduates worldwide. They will work for three years at an astronomical host institution in the United States on problems broadly related to the scientific mission of the Chandra Observatory. The Chandra X-ray Observatory Fellowship Program is a joint venture between NASA and the Chandra X-ray Observatory Center in cooperation with the host institutions.
The 2000 Fellows are: Eric Agol, a graduate of University of California at Santa Barbara, whose host institution will be California Institute of Technology; Ming Feng Gu, a graduate of Columbia University, whose host institution will be Massachusetts Institute of Technology; Jeremy Heyl, a graduate of University of California at Santa Cruz, whose host institution will be Harvard--Smithsonian Center for Astrophysics; David Strickland, a graduate of University of Birmingham (UK), whose host institution will be the Johns Hopkins University; and Jacco Vink, a graduate of University of Utrecht, whose host institution will be Columbia University.
Applications for next Fellowship competition will be due on a date to be specified in November, 2000. Further information about the Fellowship program is available at http://asc.harvard.edu/fellows/Chandra_fellow.2000.html. This site will be updated at the end of the summer for the next competition.
Back to Top
14. History of Nuclear Astrophysics Website -
Donald Clayton, Clemson University
Donald Clayton has created a website of high interest for the history of nuclear astrophysics. It makes available for the first time a large fraction of his extensive collection of photographs taken over four decades of research in nucleosynthesis. Its purpose is for scholarly historical research and for general scientific appreciation of the history of nuclear astrophysics (to the extent that the history impacted Clayton, Fowler, Hoyle, Cambridge, Heidelberg, or Clemson University). You may find it at http://photon.phys.clemson.edu/wwwpages/PhotoArchive/index.html. A CD has been given to the Center for the History of Physics containing this site. It will be continuously enlarged as even more photos are installed in Phase II.
Back to Top
15. New Translation of Galileo Poem -
Giovanni Bignami, Italian Space Agency
Everyone knows Galileo Galilei as an astronomer, physicist and writer of books that changed our perception of the world. Few people know that Galileo also wrote poetry in elegant XVI century Italian. While all major Galileo works were almost immediately translated into English, his poetry never was. Giovanni F. Bignami, a long-time AAS member, Rossi prize winner in 1993, has now translated the longest of Galileo's poems "Contro il portar la toga". It is a satiric poem of 301 lines, written in 1590 when Galileo was the poorest paid lecturer at the Pisa University. He despised and challenged Pisa's strict academic tradition especially the rule obliging professors to wear their gown at all times, under penalty of a stiff fine. To deride such rule he wrote "Against the Donning of the Gown". The poem, little known even in Italy, presents a fascinating new Galileo: mocking, witty, biting, at times shocking for his directness. The English version, in iambic pentameter, keeps the terse rhyming pattern of the original Italian and is printed vis-a-vis Galileo's Italian. Also Galileo's unsolved riddle "Enigma", in sonnet form, is translated, and a solution is proposed in graphic form. Samples of the translation (with drawings) can be found at http://www.galileounaluna.com/.
Back to Top
16. HEAD in the News: 11/99 - 5/00 -
Lynn Cominsky, HEAD Press Officer
In the past six months, many exciting discoveries in High Energy Astrophysics were publicized through the AAS e-mail distribution channel, as well as through Space Sciences Updates by NASA. Many of these stories received extensive coverage in the daily and televised news media, including some front page stories in the New York Times and the Boston Globe, network news shows and CNN. An article about new experiments in X-ray astronomy including Chandra and XMM also appeared in the January 11, 2000 New York Times.
Gamma-ray Burst News
The connection between GRBs and supernovae was a runner-up for science breakthrough in the year 1999, as assessed by the news and editorial staff of Science magazine. See Science, Volume 286, p. 2239.
Rossi Prize Winners Appear on NPR Soundprint show: Martin Rees (Cambridge) and Bohdan Paczynski (Institute for Advanced Study), two of the winners of the 2000 Rossi Prize, were among the interviewees on the half-hour radio show Soundprint, which is heard on NPR stations. The show focussed on gamma-ray bursts, and also included HEAD members Don Lamb (Chicago) and Shri Kulkarni (Caltech), as well as the Swift song. You can listen to the show if you have RealPlayer installed and go to http://soundprint.org/documentaries/2000/gamma_ray_skies/.
Photon lags in GRBs may indicate distances: Independent claims at the 5th Huntsville GRB Symposium in October 1999 by Jay Norris (NASA/GSFC) and Ed Fenimore (LANL) have indicated that the distances to GRBs may be derived from studies of the differences in arrival times between photons of different energies. Both studies have shown that the higher-energy gamma rays arrive before the lower-energy gamma rays. The amount of lag time between the two corresponds to the burst's estimated peak luminosity and distance. The lag was shorter for the more luminous bursts. For more details, see the article by Norris et al. which has been submitted to ApJ and by Fenimore et al. at http://xxx.lanl.gov/astro-ph/0004176 (also submitted to ApJ). For graphics and press information, see http://pao.gsfc.nasa.gov/gsfc/SpaceSci/gamma/gamma.htm.
Cosmic Genesis Meeting at Sonoma State University, October 28-30, 1999
Over 150 particle physicists and astrophysicists got together for the second of three planned meetings to discuss a new joint initiative from NASA, the NSF and the DoE, currently entitled "Connections: Quarks to the Cosmos." Participants at the meeting discussed ideas for future experiments that might be funded through the new initiative, as well as the theoretical ideas about the earliest moments of the Universe that need to be tested. To learn more about the conference, see the article in Science by Robert Irion, Volume 286, p. 2060. The Connections: Quarks to the Cosmos web site is found at http://www.quarkstothecosmos.org/.
HEAD Press at the January 11-15, 2000 AAS Meeting in Atlanta
For the first time since there has been a HEAD press officer, news from HEAD dominated the press at a meeting of the entire AAS. It was a very exciting meeting! Below are brief summaries of the stories that were featured.
RXTE All Sky Video Previewed to the press: On January 12, 2000, Hale Bradt (MIT) and Jean Swank (GSFC) showed a preview of the RXTE All-sky monitor video to interested press. The video was part of their Rossi prize lecture to scientists, which was given the following day. A quicktime file of the video (and other MIT RXTE videos) is available for download at http://xte.mit.edu/.
Deep observations using Chandra solve the mystery of the X-ray background: The nature of the X-ray background has been a mystery for over 35 years. Observations using Chandra, coupled with deep optical images of the same field were presented by Richard Mushotzky (GSFC) and Amy Barger (Hawaii) at a press briefing on Giant Black Holes and the Distant Universe on January 13, 2000. Additional information on the X-ray background (Brandt et al.) from the ACIS instrument was presented by Gordon Garmire at a January 14 briefing on the First Science Results from Chandra. The Mushotzky and Barger results appear in Nature, Volume 404, p. 459. You can hear Chandra Science spokesperson Wallace Tucker (CfA) discussing this result on NPR's Science Friday at http://www.sciencefriday.com/pages/2000/Jan/hour2_012100.html.
First Results from Chandra: Chandra instrument principal investigators Steven Murray (CfA/HRC), Gordon Garmire (PSU/ACIS), and Claude Canizares (MIT/HETG) presented stunning images and data from some of the first observations obtained with Chandra, at a press briefing on January 14. Murray showed HRC images of the "cool" black hole at the center of M31. Garmire showed ACIS images of the previously mentioned deep field, the black hole at the center of the Milky Way (Baganoff et al.), and an X-ray star bonanza in the Orion nebula (Feigelson et al.). Canizares showed unprecedented spectral detail in a ring of oxygen and neon that is encircling the SMC supernova remnant E0102-72. Details of all Chandra press releases can be found at http://chandra.harvard.edu/press/press_release.html.
The Nearest Microquasar: New results from RXTE and the NSF's VLA have shown that the microquasar V4641 Sgr is at a distance of about 1500 light years from Earth. Robert Hjellming (NRAO) showed radio images of the microquasar's jets and Ron Remillard and Donald Smith (MIT) provided information on its time variability as seen by the RXTE/ASM during four years. See the web pages at http://xte.mit.edu/GMSgr/ and http://www.aoc.nrao.edu/~rhjellmi/gmsgr.html for further information.
NASA Space Science Update/Mysterious New Class of Gamma-ray Sources
The discovery of a new class of gamma-ray emitting objects using CGRO/EGRET was announced at a NASA Space Science Update by CGRO Project Scientist Neil Gehrels (GSFC) and EGRET team member Isabelle Grenier (University of Paris/CEA Saclay) on March 22, 2000. There are from 20-40 of these mysterious, mid-latitude objects, which appear to be associated with the Gould Belt of massive stars and dust clouds. They have distinctly different spectral properties and timing characteristics which distinguish them from the equally mysterious high-energy galactic gamma-ray sources. For more details, see the Nature article by Gehrels et al. in Volume 404 Number 6776 Page 363 - 365 or the animations and press information at http://pao.gsfc.nasa.gov/gsfc/spacesci/structure/cgro.htm. See also the article in Science by Charles Seife, volume 287, p. 2393.
News from the Rossi 2000 Conference
There were 3 press releases sent out in conjunction with papers given at the Rossi 2000 Meeting, which was held at NASA/GSFC on March 22-24, 2000. For images that accompanied the press releases, see http://universe.gsfc.nasa.gov/press/images/rossi2000/.
Sudden spin-up seen from the Anomalous X-ray Pulsar 1RXS J1708-4009: Victoria Kaspi (MIT) presented the first evidence for the sudden change in the spin of an anomalous X-ray pulsar (AXP) - a type of slowly spinning, highly magnetized neutron star. The observed glitch in the pulsar's spin rate provides evidence that the AXPs are magnetars - neutron stars with spin rates believed to be about 1000 times higher than "normal" X-ray pulsars. It also links the AXPs to radio pulsars, which often show evidence for sudden spin rate changes.
Twin jets stretch supernova bubble: Dr. Samar Safi-Harb (GSFC) showed evidence that jets from SS433 are plowing their way through the supernova remnant W50, and causing interactions that have stretched the typically spherical shell into a shape that resembles an egg. The interactions cause a non-thermal X-ray spectrum, which was recorded by RXTE. This spectrum also provides evidence that cosmic ray acceleration in the supernova remnant is powered by the jets.
Video simulation of nuclear detonation on neutron stars: Michael Zingale (Chicago) showed a video simulation from extensive supercomputer calculations based on RXTE data of the detonation of an X-ray burst on the surface of a neutron star. Quicktime files of the simulations may be obtained at http://flash.uchicago.edu/~zingale/xray_gallery/xray_gallery.html.
Multi-wavelength observing campaign on EX Hya
Six astronomy satellites are studying the white dwarf binary EX Hya for 45 days. Observation wavelengths range from infrared through X-ray and are being done by NASA's Extreme Ultraviolet Explorer (EUVE), the Chandra X-ray Observatory (CXO), the Rossi X-ray Timing Explorer (RXTE), the Far Ultraviolet Spectroscopic Explorer (FUSE), and the Hubble Space Telescope (HST), as well as NRL's Unconventional Stellar Aspect (USA) Experiment on the Air Force's Advanced Research and Global Observation Satellite (ARGOS). You can read more about the campaign at http://www.space.com/scienceastronomy/astronomy/binary_star_search_000502.html.
Back to Top
17. "Gamma-Ray Astrophysics 2001": Baltimore, MD 4-6 April, 2001 -
Chris Shrader, NASA's Goddard Space Flight Center
The Gamma-ray Astrophysics 2001 Symposium is being organized by the NASA Goddard Space Flight Center.
The scientific program and format will contain a mixture of invited talks, contributed papers, and poster presentations covering the current status of observational and theoretical gamma ray astrophysics. Results highlighting the 9 years of the Compton Gamma Ray Observatory mission, as well as related results from other missions such as Chandra, XMM, HETE-II, and HESSI will be a major theme. In addition, ground-based VHE gamma-ray and radio observatories, and other ground-based and space missions related to astrophysical sources
with emission greater than 10 keV are solicited. Emphasis on forthcoming gamma-ray missions such as GLAST, INTEGRAL and Swift is also anticipated. Topics to be covered include all areas of Galactic and Extragalactic Astronomy, as well as Gamma-Ray Bursts, Solar Flares and Instrumentation. A "First Announcement" will be issued via e-mail in the near future. Refer to http://cossc.gsfc.nasa.gov/meetings/gamma2001/ for more information.
Back to Top
18. Ushering in a New Era: Laboratory Astrophysics with Intense Lasers -
Adam Frank, University of Rochester
Astrophysical research has traditionally been divided into observations and theory with some studies forming a combination of both. A component that has often been missing in astrophysics, however, has been the ability to quantitatively test/understand observations and models in an experimental setting where the initial and final states can be well characterized. Intense Lasers such as those used in Inertial
Confinement Fusion (ICF) are now being used to recreate critical aspects of astrophysical phenomena in the laboratory, allowing the creation of experimental tests beds where observations and models can be compared with laboratory data. Experiments are under development at intense laser facilities to test and refine our understanding of key astrophysical phenomena such as supernovae, supernovae remnants, jets and bipolar outflows, gamma-ray bursts and giant planets.
To introduce this rapidly growing field to the community, a special one day topical session on Laboratory Astrophysics with Intense Lasers will be held Tuesday, June 6, at the summer 2000 Rochester AAS meeting. The use of intense lasers for astrophysical experiments is a fundamentally new and exciting development. These studies open unique possibilities which have not existed before in the history of astrophysical research. Connsider, for example, that experiments with intense laser systems have already demonstrated the feasibility of creating high Mach number radiative jets with properties that scale directly to proto-stellar flows. Such studies are simply not possible via any other means. When the National Ignition Facility (NIF) is finished
at LLNL the increased power of its lasers will further broaden the parameter space domains open to laboratory astrophysics. The special session will give astronomers a chance to obtain a broad overview of the field. Presentations will provide an introduction to both the theoretical and experimental issues involved in Laser Astrophysics. A number of ongoing experimental programs will be presented as well as future prospects with new laser systems coming line in the near future. The program for Session 22 at the Rochester AAS Meeting is at http://www.aas.org/publications/baas/v32n2/aas196/S220.htm.
Back to Top
19. A Letter to the Membership
Message to members of the American Astronomical Society's High Energy Astrophysics Division, authorized by the HEAD Officers.
This message is being sent because it is likely to be of interest to many HEAD members. It does not constitute an endorsement by HEAD or by the AAS as a whole.
May 23, 2000
As members of the High Energy Astrophysics Division, we are concerned about the plan to de-orbit the Compton Gamma-Ray Observatory (CGRO) in early June. We are writing to you as individuals to express our support to the recent call by Jim Ryan et al for a campaign to urge NASA to reconsider the planned destruction of CGRO. Their letter also calls for the appointment of an independent panel to reevaluate all the options.
We are concerned by the large uncertainty associated with the risk analysis reported so far and the great scientific loss incurred by such an irreversible decision.
We are certain that you are aware of the scientific importance of CGRO for astrophysical and solar observations. Until the launch of HESSI, INTEGRAL, HETE, SWIFT, and GLAST, CGRO providesthe only observations of various sources of high-energy radiation. As one of the 3 great observatories that costs over $600 M to build, CGRO is a true national and world treasure that is irreplaceable. It perfectly complements the other two great observatories, as well as the upcoming missions listed above. A premature termination of CGRO would be a great tragedy for
science if a dramatic high energy event occurs in the near future (such as a nearby supernova or a March 5, 1979-like event). Moreover, even a planned de-orbit is not risk-free. Given the ongoing budget process in Congress for FY01, it would seem prudent to delay the de-orbit at least until after the FY01 budget is settled. That would give NASA extra time to have a full independent review of all options.
We therefore urge you to support the letter campaign for a delay in the termination of the CGRO mission until an independent review panel can ascertain the risks and explore all options. If you feel uncomfortable about lobbying Congress directly on this issue, then at least a short letter to NASA headquarters may be helpful. Time is short and the re-entry process begins on May 28.
For a copy of the letter that has been distributed by Jim Ryan and signed by Ryan, Paciesas and Briggs see http://wwwgro.unh.edu/comptel/.
Elena Aprile, Columbia University
Roger Chevalier, U. of Virginia
Don Clayton, Clemson University
Kevin Hurley, U.C. Berkeley
Mark Leising, Clemson University
Edison Liang, Rice University
Stan Woosley, U.C. Santa Cruz
Back to Top
20. Editor's Comment - Paul Hertz, NASA Headquarters, HEAD Secretary-Treasurer
Message to members of the American Astronomical Society's High Energy Astrophysics Division, authorized by the HEAD Officers.
This message is being sent because it is likely to be of interest to many HEAD members. It does not constitute an endorsement by HEAD or by the AAS as a whole.
The risk of a human fatality during an uncontrolled reentry of CGRO is 1 in 1000. This is unacceptable to NASA, as it should be to you. All spacecraft systems necessary for a safe and reliable reentry of CGRO are currently working. There is no alternate mode of reentry that has been developed and proven. Any alternative which calls for the continuing operation of CGRO for any reason, including as a scientific observatory, adds additional risk to human life. NASA chose the path of the safest and most reliable means of deorbiting CGRO. The loss to science is a regrettable consequence of this choice.
Paul Hertz, NASA Headquarters
Back to Top
21. Paul Nandra wins AAS Pierce Prize -
Lynn Cominsky, Sonoma State University, HEAD Press Officer
The American Astronomical Society has named Dr. Paul Nandra at NASA Goddard Space Flight Center the winner of the 2000 Newton Lacy Pierce Prize for his work on black holes. The Pierce Prize is awarded annually for outstanding achievement in observational astronomical research over the previous five years to astronomers younger than 36 years.
Nandra, a Universities Space Research Association scientist working at Goddard, was nominated for the award for a series of seminal journal articles concerning the fate of iron atoms very close to supermassive black holes. In one 1999 article, Nandra documented what may be the first evidence of matter falling into a black hole, as opposed to the more readily observed phenomena of matter swirling around the black hole or shooting away.
"I am surprised and delighted to win the award," said Nandra. "It feels great to be recognized in this way, but many others here at NASA and elsewhere deserve a lot of the credit. I'm lucky to have had the opportunity to work with those people and make a contribution to such an exciting subject area."
Also among Nandra's accomplishments was a 1997 article stating that the X-ray light spectrum of iron in Active Galactic Nuclei (galaxies with bright cores) is commonly redshifted and broadened -- that is, stretched out compared to the normal dips and peaks of a light spectrum. This demonstrated that there is a black hole in the center of these galaxies, and that the radiation gets distorted in a specific way by the extreme gravitational field.
A popular target for Nandra's observations is galaxy NGC 3516, suspected to harbor a supermassive black hole. Much of Nandra's data come by way of the Advanced Satellite for Cosmology and Astrophysics (ASCA), a Japanese/US X-ray satellite launched in 1993, and the Rossi X-ray Timing Explorer, a NASA satellite launched in 1995.
Nandra graduated from Cambridge University in 1987 and received a Ph.D. in X-ray Astronomy from Leicester University, UK. He has held several positions at Goddard's Laboratory for High Energy Astrophysics in Greenbelt, Md., since 1995. He will present the Pierce Prize lecture at the January 2001 meeting of the American Astronomical Society, to be held in San Diego, Calif.
Back to Top
22. "X-ray Astronomy 2000": Palermo, Italy, 4-8 September 2000 -
Have you seen our web site recently?
We are pleased to inform you that the new programme framework and other interesting information about the meeting are on the web at http://www.astropa.unipa.it/EVENTS/XRAY2000/.
Back to Top
23. "New Century of X-ray Astronomy": Yokahama, Japan, 6-8 March 2001 -
Hajime Inoue, Institute of Space and Astronautical Science
This is the first announcement of an X-ray symposium entitled "New Century of X-ray Astronomy", which is planned in March 2001, at Yokohama, Japan. It should be the first X-ray symposium in the twenty-first century.
Following two subjects will be the major goals of the symposium. The first half of the symposium will be dedicated for the latest reports from the two giant missions, Chandra and Newton, with ongoing missions, ASCA, Beppo-SAX, and RXTE. Here we would like to ask speakers to put emphasis not on the individual results but on the basic problems revealed by these recent observations. They will point the direction of the X-ray astronomy in the coming new century, which should be discussed in the latter half of the symposium. Possible future missions to investigate these problems could be the high resolution spectroscopy mission, the hard X-ray imaging telescopes, extra-large area (> a few tens of square meter) telescopes, X-ray interferometers and so on. It would be also important to listen to the scientific point of views of astronomers in different wave bands and theories. The final goal is the discussion of the prospects of X-ray astronomy in long time range such as the first few decades of the new century.
The programme will include several sessions with a couple of review talks and several contribution papers in each session. Major issues in the programme are:
1. Highlights of current missions,
2. Problems revealed by the missions of the 20th Century,
3. Science and technology of missions in the 21st Century.
Poster sessions will be held in parallel to the oral sessions. We consider a special arrangement to submit all proceeding papers to a refereed journal.
Organizing Committee will arrange the details of the programme, consulting the International Advisory Committee: Prahlad Agrawal (TIFR, India), Roger Blandford (CalTech, USA), Giuseppina Fabbiano (CFA, USA), Guenter Hasinger(AIP, Germany), Katsuji Koyama(Kyoto Univ., Japan), Kazuo Makishima (Univ. of Tokyo, Japan), Luigi Piro (IAS, C.N.R. Rome, Italy), Arvind Parmar (ESTEC, Netherlands), Hiroshi Tsunemi (Osaka Univ.), Martin Turner (Univ. of Leicester, UK), Nicholas White (NASA/GSFC, USA).
The symposium will be provided by the organizing committee: Hajime Inoue (ISAS, Japan: Chair), Hideyo Kunieda (ISAS, Secretary), Nobuyuki Kawai (RIKEN), Shunji Kitamoto (Osaka Univ.), Kazuhisa Mitsuda (ISAS), Takaya Ohashi (Tokyo Met. Univ.), Tadayuki Takahashi (ISAS), Yuzuru Tawara (Nagoya Univ.).
For the real operation of the symposium, Organizing Committee will ask the help by the Science Secretaries.
Web page is ready at http://www.astro.isas.ac.jp/conference/newcentx/index-e.html.
If you are interested in this symposium, please submit Preliminary Registration Form before 15 August, 2000 to keep you informed for the symposium (the second circular will be sent in September 2000 with registration forms). If you do not have an access to the web or would like to alter some information that was submitted, please e-mail us or fax to the contact address:
The Institute of Space and Astronautical Science
3-1-1 Yoshinodai, Sagamihara, Kanagawa, 229-8510 Japan
The location of the symposium site is in the heart of the Yokohama water front area. This is the first port opened to foreign countries after the long seclusion of Japan in Edo era. Now a days, it is renovated to an attractive area for all generations with various amusement facilities, shopping malls, and hotels. It is about 30 km south west of Tokyo. Shinkansen, the bullet-train will allow us to get Nagoya, Kyoto and Osaka within a few hours from Yokohama.
We are looking forward to seeing you at this exciting symposium.
Back to Top
Back to Top
HEADNEWS, the electronic newsletter of the High Energy Astrophysics Division of the American Astronomical Society, is issued twice yearly by the HEAD Secretary-Treasurer. The HEAD Executive Committee Members are: