******************************************************************* * * * SSSSSS OOOOOO N N GGGGGG N N * * S O O NN N G G NN N * * S O O N N N G N N N ee ee w w sssss * * SSSSSS O O N N N G N N N e e w w s * * S O O N N N G GG N N N eeeee w w w sssss * * S O O N NN G G N NN e w w w s * * SSSSSS OOOOOO N N GGGGGG N N eeeee wwwww sssss * * * ******************************************************************* * * * Issue No. 2 SONGNews 23 Oct. 1996 * * * * Newsletter of the Stellar Oscillations Network Group * * * ******************************************************************* * * * SONGNews is distributed from the National Optical Astronomy * * Observatories - Send articles to be included to song@noao.edu. * * To add your name (or delete) to the SONGNews distribution list * * send email to the same address. Issues are also available via * * the World Wide Web at http://www.noao.edu (click on SONG). * * * ******************************************************************* * * * * * CONTENTS OF THIS ISSUE: * * * * 1. Status and Use of the EST-MUSICOS Spectrometer at INT * * 2. Meeting Announcement - IAU Symposium 189 * * 3. Meeting Announcement - Meeting to Honor Art Cox * * 4. Meeting Announcement - 10th Cambridge Workshop * * 5. Meeting Announcement - Asteroseismology at the IAU * * 6. Recent Abstracts in Asteroseismology * * 7. Status Report on the The Procyon Campaign * * * ******************************************************************* ******************************************************************* From: Bernard H. Foing Solar System Division ESA Space Science Department ESTEC (SO), postbus 299 NL-2200 AG, Noordwijk The Netherlands bfoing@estec.esa.nl Subject: Status and use of ESA-MUSICOS spectrometer at INT Dear Colleague: I hope you had good holidays in all sites around the world! A copy of the MUSICOS spectrograph was integrated in the Solar System division in fall 1995, and tested in the lab at ESTEC. We brought the Dutch Sun via the fiber to the spectrometer. Solar observing, besides spectrograph performance evaluation, can serve to monitor the tiny variations due to oscillations or chromospheric activity. The ESA-MUSICOS spectrograph was then installed and commissioned successfully at the end of April 1996 on the 2.5 m Isaac Newton telescope at La Palma observatory. First light was obtained on first night. Specific MUSICOS echelle reduction routines have been developed in MIDAS and IRAF environments. Scientific results from this commissioning run include the assessment of the ESA-MUSICOS performances at INT (with R. Le Poole and H. Stempels), studies of wind and variability of hot stars (with J. de Jong), diffuse interstellar bands (with J. Cami, P. Sonnentrucker and P. Ehrenfreund), and the activity of the near break-up rotator FK Comae (with J. Oliveira and P. Gondoin). I thank C. Catala, J. Baudrand, E. Lesserteur (CNRS, F), T. Beaufort, T. Appourchaux, E. Houdebine, U. Telljohann (SO division), research students (L. Duvet, M. Gray, J. Oliveira, H. Stempels) for their contribution to the ESA-MUSICOS instrument, and the whole MUSICOS collaboration for their large instrumental, observational, data analysis and interpretation efforts. You can find by attached mail a copy of the master report written by Joana Oliveira on her research done with the ESA-MUSICOS spectrograph at INT. We shall use the spectrograph at INT on 15-26 November as part of the next worldwide MUSICOS campaign on 15-30 November 1996 (information on MUSICOS96 homepage at: http://star-www.st-and.ac.uk/~acc4/musicos96.html). I wish also to call on you for proposing collaborative observations using the ESA-MUSICOS spectrometer at INT for 1997. UK and international deadline is end of September 1996 for applying for first semester 1997. In addition we have also tested in June 1996 the possibility of using two transportable automatic telescopes for CCD photometry. We intend to support the MUSICOS96 campaign with these photometric observations as necessary. We have also developed a mode for remote control of the telescopes and CCD cameras. Please contact me if you are interested by using these instruments and for further information. ********************************************************************* ********************************************************************* 2. Meeting Announcement - IAU Symposium 189 FUNDAMENTAL STELLAR PROPERTIES: THE INTERACTION BETWEEN OBSERVATION AND THEORY (A meeting to mark the 80th birthday of Emeritus Prof. R. Hanbury Brown) 13th -- 17th January 1997 Women's College, University of Sydney, Australia SECOND ANNOUNCEMENT AND CALL FOR PAPERS AND REGISTRATION Abstract deadline: 30 September 1996 Early registration deadline: 31 October 1996 WWW page: http://www.physics.usyd.edu.au/astron/second.html Anonymous ftp: ftp.physics.usyd.edu.au (in the directory fsp97) E-mail: fsp97@physics.usyd.edu.au *************************************************************************** *************************************************************************** 3. Meeting Announcement - Meeting to Honor Art Cox First Announcement A HALF CENTURY OF STELLAR PULSATION INTERPRETATIONS: A TRIBUTE TO ARTHUR N. COX 1997 June 16-20 (Mon - Fri) Los Alamos National Laboratory Los Alamos, New Mexico, USA We invite you to attend this meeting in honour of Art Cox's many contributions to stellar pulsation. This meeting continues the series of pulsation conferences initiated by Art Cox in 1971, and held most recently in Cape Town, South Africa (February 1995) and Victoria, Canada (July 1992). Scientific Content of Meeting ----------------------------- We have chosen the theme in recognition of the diversity of Art Cox's interests and theoretical contributions to the understanding of nearly every type of variable star. We are organizing the conference around unifying physics issues rather than around the traditional divisions by variable star class. Our hope is that this structure will provide a different flavor to the meeting, stimulate discussion between specialists in different classes of variable stars, and inspire originality in review talks. We encourage participants to consider underlying physics or observational properties that may be common to several classes of variable stars, and to discuss physical and observational connections. We hope that such discussions will facilitate new insights on how to study variable stars and help people look beyond their traditional areas of expertise for guidance in solving current outstanding stellar pulsation problems. We also invite talks concerning the status of our understanding on particular classes of variable stars, but encourage participants to present their research in the larger perspective of a specific physics issue. While the conference will highlight Art's lifetime career interests, we wish to encourage the presentation of results on new and exciting variable star / pulsation research. Meeting Format -------------- We expect to have 10 oral sessions on the topics listed below, in addition to separate poster sessions. The oral sessions will include an invited review talk (45 minutes), one or more invited contributed talks (30 minutes), and several contributed talks (15 minutes). We will issue a call for abstracts in the 2nd Announcement December 15, and abstracts will be due March 15. If the number of talks/posters submitted exceeds the available space and time, the Scientific Organizing Committee will choose among the abstracts, and inform the presenters by April 30. We will send information regarding hotel accommodations, tours, and special events in the 2nd announcement to be sent December 15. SESSION TOPICS and CONFIRMED INVITED REVIEW SPEAKERS ---------------------------------------------------- Overview of Arthur Cox's Career John Castor: Lawrence Livermore National Laboratory, USA 1. Linear theory of radial and nonradial pulsation H. Shibahashi: University of Tokyo, JAPAN 2. Nonlinear pulsation theory J. R. Buchler; University of Florida, USA 3. Opacities and the equation of state F. J. Rogers; Lawrence Livermore Laboratory, USA 4. Stability, driving mechanisms, amplitudes, growth rates, mode selection A. Noels; U. Liege, BELGIUM 5. Helio- and asteroseismology W. Dziembowski: Copernicus Astronomical Center, POLAND 6. Evolution/pulsation connections (abundances, diffusion, mixing, mass loss, period changes, rotation, how pulsation properties help determine evolutionary state) I. Iben; University of Illinois, USA 7. Mass loss, outbursts, shocks, envelope instabilities D. Sasselov; Harvard-Smithsonian Center for Astrophysics, USA 8. Pulsation/convection interaction G. Bono; Trieste Astronomical Observatory, ITALY 9. Spectral and photometric variability (line width, strength, profile variations, new or better-defined variable star classes) L. Balona; South African Astronomical Observatory, SOUTH AFRICA 10. New observing techniques (MACHO, EROS, HST, networks, HIPPARCOS) D. Welch; McMaster University, Ontario, CANADA Scientific Organizing Committee ------------------------------- Bob Stobie [Chair, rss@saao.ac.za] (South Africa, Cepheids) Michel Breger (Austria, delta Scuti stars) Carla Cacciari (Italy, RR Lyraes) Jessica Chapman (Australia, Miras) Joyce Guzik [LOC Chair] (USA, Sun, delta Scuti stars) S O Kepler (Brazil, degenerate pulsators) Geza Kovacs (Hungary, RR Lyraes) Henny Lamers (Netherlands, LBVs) Pawel Moskalik (Poland, B stars, pulsation theory) James Nemec (Canada, SX Phe stars) John Percy (Canada, long-period variables) Dimitar Sasselov (USA, pulsation theory) Hiromoto Shibahashi (Japan, pulsation theory) Chris Waelkens (Belgium, B stars) Doug Welch (Canada, Cepheids) Local Organizing Committee -------------------------- Joyce A. Guzik [chair, joy@LANL.GOV] Paul A. Bradley [co-chair, pbradley@LANL.GOV] Thomas E. Beach Stephen A. Becker C. G. Davis, Jr. Robert G. Deupree Galen R. Gisler David E. Hollowell David S. King Michael S. Soukup Warren M. Sparks Please share this information with your colleagues who may not have received this E-mail announcement. ============================================================================= PRE-REGISTRATION FORM ============================================================================= A HALF CENTURY OF STELLAR PULSATION INTERPRETATIONS: A TRIBUTE TO ARTHUR N. COX 1997 June 16-20 (Mon - Fri) Los Alamos National Laboratory Los Alamos, New Mexico, USA Name: _________________________________ Postal Address: _________________________________ _________________________________ _________________________________ Telephone: _________________________________ FAX: _________________________________ E-mail address: _________________________________ Please X one response: _____ I will definitely attend _____ I will probably attend _____ I may attend _____ I will not attend I would like to present a paper. I prefer a: _____Contributed talk _____Poster Tentative Title: (Abstracts will be due March 15) ============================================================================= Please reply (preferably by E-mail) by DECEMBER 1 to: joy@LANL.GOV Joyce Guzik XTA MS B220 Los Alamos National Laboratory Los Alamos, NM 87545 USA *********************************************************************** *********************************************************************** 4. Meeting Announcement - 10th Cambridge Workshop THE TENTH CAMBRIDGE WORKSHOP ON COOL STARS, STELLAR SYSTEMS AND THE SUN July 15 - 19, 1997 Cambridge, Massachusetts Harvard-Smithsonian Center for Astrophysics ******** FIRST ANNOUNCEMENT *********** ANNOUNCEMENT: The First Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun was held nearly twenty years ago, with about fifty scientists (mostly from the New England area) attending. Since that time, the workshops have grown into a major conference with international attendance, and have been held at a variety of sites including Boulder, Seattle, Tucson, Athens, GA. The most recent meeting shifted to the other side of the Atlantic to Florence, Italy, and was attended by nearly 300 astronomers. We have decided to return home to the original site for the 10th Cool Stars Workshop. The increase in size of the meetings reflects a general increase in interest in the solar-stellar connection and the improvement in our ability to study these phenomena with the availability of current generation instrumentation such as SOHO, HST, GONG and HIPPARCOS. We expect this to be the largest and most exciting meeting of the series, and with this announcement we invite you to participate in the meeting. Scientific Organizing Committee: Balachandran (Maryland), Bookbinder (CfA), Caillault (Georgia), Carpenter (GSFC), Collier-Cameron (St. Andrews), Dere (NRL), Donahue (CfA), Dupree (Chair; CfA), Giampapa (NOAO), Gilliland (STScI), Jordan (Oxford), Linsky (JILA), Montmerle (CEA Saclay), Pallavicini (Palermo), Rebolo (IAC), Sakurai (NAO), Schmitt (MPE-Garching), Stauffer (CfA), Strassmeier (Vienna), Title (Lockheed), White (GSFC) and Zinnecker (Potsdam). Local Organizing Committee: Bookbinder, Brickhouse, Cornell, Deeley, Donahue, Hartmann (Co-Chair), Sasselov, Stauffer (Co-Chair), and Uitenbroek. The meeting will cover a large variety of solar-stellar topics, ranging from helioseismological observations of the interior structure and rotation rate of the Sun to the search for planets around nearby stars, and from submillimeter observations of star-forming regions to x-ray observations of stellar coronae. We have not yet finalized the program for the meeting, but the specific topics which we expect will be covered include very low mass stars and brown dwarfs, stellar activity cycles, helio/asteroseismology, surface imaging of the Sun and stars, stellar coronae in the AXAF/XMM era, variable stars from Hipparcos and the MACHO surveys, the connection between rotation and lithium abundance in low mass stars, etc. Conference Location: The workshop will be held at the Cambridge Marriott Hotel, in Kendall Square near MIT. The Marriott is directly at a subway stop, providing easy access to both Harvard Square and to Boston. There are many summer activities in the area; the LOC will offer a variety of extra-curricular options. In the second announcement, we will provide details on registration for hotel accommodations. Schedule: This is the first announcement of the meeting. If you would like to receive further information, we ask that you pre-register for the meeting by using our online form at URL: http://cfa-www.harvard.edu/CS10/prereg.cgi or using the attached questionnaire BY EMAIL. (not included here. -ed.) The second announcement will be sent in November. It will contain the agenda with a list of invited speakers and special sessions, plus more detailed information about the logistics, proceedings, and the social program. Further information can be obtained by contacting our Web site at URL: http://cfa-www.harvard.edu/CS10/ or by sending e-mail to us at: cs10@cfa.harvard.edu Sincerely, the CS10 LOC *********************************************************************** *********************************************************************** 5. Meeting Announcement - Asteroseismology at the IAU IAU Symposium No. 185, "New Eyes to See Inside the Sun and Stars: Pushing the limits of Helio and Asteroseismology with New Observations from the Ground and from Space, Kyoto, Japan, 18-22 August 1997 (concurrent with the IAU General Assembly in Kyoto). The contact is Dr. F. L. Deubner (in Wuerzburg, Germany), deubner@astro.uni-wuerzburg.de *********************************************************************** *********************************************************************** 6. Recent Abstracts "Improved atmosphere models and CM description in models of Delta Scuti and pulsating Ap stars. Influence on the frequencies" Nathalie Audard, Friedrich Kupka, Pierre Morel, Werner W. Weiss We have computed stellar models and eigenmodes for Delta Scuti and pulsating Ap stars. For comparisons, models were computed with atmospheres reconstructed with T(tau) laws derived from Kurucz's model atmospheres, using either MLT or Canuto and Mazitelli's (1991; hereafter CM) formalisms, and with the radiative Hopf law. For some Ap stars, frequencies are observed which are larger than the theoretical acoustic cut-off frequency, strongly depending on the T(tau) relation in the atmosphere. The spectra of eigenfrequencies computed for models which implement Kurucz's model atmospheres have a larger acoustic cut-off frequency than those for models based on a purely radiative T(tau) relation. This leads to a better agreement with the observations. This increase of the acoustic cut-off frequency is in agreement with Shibahashi and Saio (1985) who used an analytical T(tau) relation based on a single Kurucz's (1979) model. For Ap stars, Shibahashi and Saio (1985), Matthews et al (1990, 1996), and Kurtz and Medupe (1996) argued that this increase might be caused by a steeper temperature gradient. Our results, however, show that Kurucz's atmospheres decrease this gradient. On the other hand, the CM description produces a steeper temperature gradient, but does not influence significantly the cut-off frequency. Thus we can conclude that the major factor is whether or not frequency-dependent treatment of radiative transfert and convection are included in the models, and not whether convection is described by the MLT or CM formalism. More details will be found in Audard et al (1996, A&A, in preparation, and in the proceedings of the IAU181 colloquium held in Nice 30 Sept-3 Oct 1996). *********************************************************************** "Asteroseismology from Equivalent Widths: A Test of the Sun and Methodologies for Stellar Observations" C. U. Keller, J. W. Harvey, S. C. Barden, C. A. Pilachowski, F. Hill, and M. Giampapa Kjeldsen et al (1995) reported a probable detection of solar-like, low-amplitude, p-mode oscillations of eta Bootes using equivalent width measurements from low-resolution spectra of the hydrogen Balmer lines. Here we explore the usefulness of this technique on a variety of telescopes and spectrographs. Observations of integrated sunlight over a 4-hour period using the McMath-Pierce solar telescope reveal the 5-minute solar oscillations at the expected amplitude. Data from the Kitt Peak coude feed and 2.1-m telescopes are used to develop observing and data reduction techniques, such as a synchronized timing system to maintain evenly spaced temporal samples, improved CCD readout efficiencies to increase the duty cycle of observations, and simulations of the probability of a detection as a function of observing run length. - Submitted to the Publications of the Astronomical Society of the Pacific ******************************************************************* ******************************************************************* 7. A Status Report on the the Procyon Campaign The Stellar Oscillations Network Group at NOAO will monitor the star Procyon with the coude feed telescope on Kitt Peak to search for p-mode oscillations using the equivalent width technique. Weather permitting, observations will commence on January 10, 1997, and will continue for 5 weeks. Spectra will cover the region from 3800-5300A, at a reciprocal dispersion of 0.4 A/pixel. Primary emphasis will be on the measurement of the equivalent widths of H-beta, -gamma, and -delta for asteroseismology. As we write this, we are in the process of setting up protocols for calibrations, observations, and data reductions. As information becomes available, we will post it to our web pages, accessible via the NOAO home page at http://www.noao.edu. Tim Bedding and his collaborators have obtained 12 nights at Mt. Stromlo at the end of January to participate in the Procyon campaign, and we have received expressions of interest from a few other observatories as well. Both Doppler velocity data and equivalent width data are needed. If you are interested in participating in this campaign, please contact one of us at NOAO (S. Barden, M. Giampapa, J. Harvey, F. Hill, C. Keller, or C. Pilachowski) or send email to song@noao.edu for details. ********************************************************* *********************************************************o The National Optical Astronomy Observatories are operated by the Association of Universities for Research in Astronomy, Inc. under cooperative agreement with the National Science Foundation. ************