IAU Commission 30: Radial velocities Newsletter 1998/1 Dear members and consultants of IAU Commission 30, As the incoming president of commission 30, this is my first attempt to communicate with all members through a newsletter. I am planning to issue these newsletters irregularly, probably once or twice a year over the coming three years. 1 Officers and organizing committee: IAU Commission 30 has a president, vice-president and an organizing committee of 8 people. The composition of president, vice-president and of the committee changed at the Commission 30 meeting in Kyoto. First, let me thank the outgoing president, Colin Scarfe, for his many reforms of our commission, in particular for instituting a more democratic process for electing the officers and organizing committee. In the new system, the president serves for 3 years, the VP for 3 then normally becomes the new president, while OC members serve for 6 years with four new members every three years. Nominations for the new VP and four new OC members take place every three years, at least 3 months before a General Assembly of the IAU, and any two Commission 30 members can nominate any other member for one of these posts. That's a summary of our democratic procedure, which I will implement next in 2000. For your information the individuals serving as president, VP and on the OC are now: President: John Hearnshaw (that's me!) University of Canterbury, Christchurch, New Zealand Fax: +64 (3) 3642469 email: j.hearnshaw@phys.canterbury.ac.nz Vice-president: Andrei Tokovinin Sternberg State Astronomical Institute Moscow, Russia Fax: +7 095 939 16 61 email: toko@sai.msu.su Organizing committee: a) serving until 2000 Bill Cochran Univ. Texas, Austin, USA Frank Fekel Tennessee State Univ., Nashville, TN, USA Birgitta Nordstrom Niels Bohr Institute for Astronomy, Copenhagen Bob Stefanik Center for Astrophysics, Cambridge, MA, USA b) serving until 2003 Tsevi Mazeh Wise Observatory, Israel Nidia Morrell Univ. Nacional de La Plata, Argentina Hernan Qintana Univ. Catolica de Chile, Santiago, Chile Stephane Udry Geneva Observ., Switzerland Among the functions of the OC is that of advising the president and vice-president and helping compile our triennial report (more on that later) as well as commenting on the requests for our commission's support in applications for IAU conferences. 2 Some general thoughts on membership: Commission 30 is a small IAU commission, with only about 100 members. Perhaps it is surprising that a commission devoted to the application of the Doppler effect, which is pervasive in so many branches of astronomy, should be so poorly represented. In IAU Information Bulletin 68 (July 1992) there is a list of the membership of the then 40 IAU commissions. The four largest had over 500 members, while 20 had at least 200. Only 5 commissions were smaller than commission 30. Although the data are now over 5 years out of date, I suspect the present situation will still be similar. I should remind all members that Commission 30 has a long and illustrious history. Ours was one of the founding commissions of the IAU when the Union was established in 1920. At the first General Assembly in Rome in 1922 we had W.W. Campbell as commission president, and there were just six other members. Over the years commissions of the IAU have come and gone. I see the position of Commission 30 as fairly weak and vulnerable, mainly because our work overlaps with that of several other commissions. For example, the members of commissions 9 (instruments and techniques), 10 (solar activity), 26 (double and multiple stars), 27 (variable stars), 28 (galaxies), 29 (stellar spectra), 33 (dynamics of Galactic system), 34 (ISM), 37 (star clusters), 40 (radio astronomy), 42 (close binary stars) and even 51 (bioastronomy) may well measure radial velocities but not be members of commission 30. And my guess is that if Commission 30 were suddenly to disappear, then these members of other commissions would continue to ply their trade, more or less oblivious of our disappearance. However, I believe that would be a great pity, for several reasons. One is the continuity of our triennial reports, which have created over the last 75 years valuable snapshots of the state of the art of radial- velocity measurement. Such specific information on radial velocities is generally absent from the reports of other commissions or from elsewhere in the astronomical literature. For those interested in historical development of the subject, these reports are invaluable. Furthermore, for some astronomers, radial-velocity measurements are their most important activity. For example, for a new graduate student starting out in this branch of astronomy, and wishing to become rapidly conversant with the latest developments, then reading the latest Commission 30 triennial report would be one excellent means of becoming acquainted with the radial-velocity literature. As you probably know, the IAU commissions were placed into larger divisional groupings in 1994, and Commission 30 was placed into Division IX together with commission 9 (instruments and techniques) and 25 (stellar photometry). Division IX is one of the smaller divisions, but it is also a unique one, because its emphasis is on observational techniques rather than a specific type of astronomical object. That may be another reason for preserving our integrity, because we provide a somewhat different emphasis from that of most other IAU commissions. One reason for saying all this is that the future viability of Commission 30 may well depend on increasing our membership. Given the large number of radial-velocity workers in the IAU, I suspect that we could justify having a membership of around 200 instead of 100. Most Commission 30 members probably have colleagues who also sometimes measure radial velocities but are not members. The way to join Commission 30 is for any IAU member to contact me, and assuming they are genuinely interested and active in radial velocities, then I am able to appoint them as a member. IF EVERY PRESENT MEMBER COOPTS ONE OR TWO COLLEAGUES IN THIS WAY, THEN OUR MEMBERSHIP WILL OBVIOUSLY GROW SUBSTANTIALLY. I will report on this matter in future newsletters, and may even award a prize to the member who attracts the greatest number of new recruits before the next IAU General Assembly in August 2000 in Manchester! I should mention here there is just one restriction to having IAU members join Commission 30, namely that the IAU itself has a rule limiting the number of commissions which members may join to three (the limit is in fact one for the first three years after joining the IAU itself). This rule is not rigorously policed or adhered to, but I think it is a guideline we should bear in mind when trying to coopt new members to our commission. By the way, astronomers can also join Commission 30 as consultants, even if they are not members of the IAU. However this requires the approval of the IAU Executive Committee and takes place at a General Assembly. Normally a consultant is expected to become an IAU member and hence also a commission member at the next General Assembly after becoming a consultant. Commission 30 currently has three consultants, and these three should ensure they are nominated by their national committees to become IAU members in the year 2000. (There is information on national committee contact addresses in IAU Information Bull 71 (1993), though not very up-to-date.) This is also a good time to remind you that Commission 30 is concerned with the radial velocities of both stars and galaxies, and in principle, of the interstellar medium. However, so far as I am aware, only five of our members are actually working in velocities of the ISM. That is one area that I would welcome more members. In addition, we are involved with radial velocities in any wavelength domain; traditionally that has meant optical ground-based spectroscopy or 21-cm radio work. However there may well be instances when other wavelength regions, especially UV and IR, can also contribute. Perhaps we should look towards recruiting members who are expert in these wavelengths too. So far only two Commission 30 members have indicated interests in radial-velocity measurement outside the optical or radio regions. Three years ago, our ex-president, Colin Scarfe, and myself set up a system of areas of research with corresponding codes, and we invited all members to specify the areas of radial-velocity research which were of interest to them. Fifty-one members responded to this request, which is about half of the membership. I WOULD VERY MUCH LIKE TO EXTEND THE RESPONSE TO THE OTHER HALF OF OUR MEMBERS, SO AS TO HAVE MORE COMPLETE INFORMATION. To help you do this, I am appending the current list of radial-velocity codes (see section 7 of this newsletter) and I would be grateful if you could let me know your current area of research interest. I am also sending you in a separate email or by airmail a list of members including email addresses, posrtal addresses and areas of interest. Please update this where necessary and return to me. At this stage you may be interested to know that of the 51 responses for areas of research interest: 47 indicated an interest in stellar radial velocities 10 indicated an interest in galaxy radial velocities or of objects within other galaxies 5 indicated an interest in the ISM and its radial velocities 2 indicated an interest in RV using other than optical or radio wavelengths Clearly there are large imbalances in our distribution of expertise compared with those of all astronomers interested in radial velocities. It may also be of interest to know what our country distribution is among the Commission 30 membership. According to my latest information the results are: USA 34 France 16 Canada 10 Russia 7 Switzerland, UK 5 Argentina, Germany 4 New Zealand, Denmark, Australia, Chile, Belgium 2 Austria, South Africa, Netherlands, China, Iraq, Sweden, Israel, Italy, Brazil, Ukraine, India, Venezuela 1 Total membership (including 3 consultants) = 107 Europe 46 N America 44 Asia-Pacific (inc South Africa) 7 S America 8 Middle East 2 Perhaps it is no suprise that USA, France and Canada are all in double figures, as their pre-eminence in this field was already well known. But what is clear is that several major astronomical nations, some of them doing lots of radial velocity work, have very few members of Commission 30. Once again, some action is needed to redress this imbalance. 3 Forthcoming IAU Colloquium on Precise Stellar Radial Velocities: Many Commission 30 members will already be aware that in June this year there will be a conference on precise stellar radial velocities. Organizing this meeting will be a major activity for Commission 30 in the current triennium. The dates will be Sunday 21 to Friday 26 June 1998 and the venue is Victoria, BC, Canada (which some astronomers would still regard as the radial-velocity capital of the world!). By precise stellar radial velocities we mean those with random error bars of 100 m/s or better, though work with precisions of up to 300 m/s will also be accepted. At the time of writing the Second Announcement for IAU Colloquium 170 has just been issued. If you have not received this, but wish to do so, then you should contact the LOC secretary, Lorraine Charron at email charron@uvvm.uvic.ca or by writing to IAU Colloquium 170, Dept of Physics and Astronomy, University of Victoria, P.O. Box 3055, STN CSC, Victoria BC, V8W 3P6, Canada. Fax +1 (250) 721 7715. There is also a WWW homepage for the colloquium, which you can visit at the following URL: http://astrowww.phys.uvic.ca/prvs/prvs.html At this point I will simply mention a few salient facts concerning the scientific programme. The topics to be covered are fairly broad, as follows: 1) Instrumentation for precise radial velocities 2) Data reduction techniques for precise radial velocities 3) Planetary and brown-dwarf candidates discovered using precise radial velocities 4) Combining precise radial velocities with interferometric and astrometric data for the analysis of orbits 5) Asteroseismology and the study of pulsating stars with precise radial velocities 6) Velocity analysis for rotating stars and stars with surface features 7) Other astrophysical phenomena relevant to precise radial-velocity measurements, including convection, turbulence, mass outflows, rotation, gravitational redshifts, chromospheric activity and line asymmetry 8) Precise radial velocities for standard stars. Bibliographies and catalogues of precise radial-velocity data 9) Historical summary of past trends and the future of precise radial-velocity determinations There are 24 confirmed invited speakers who will present invited reviews at the colloquium. They are: A. Baranne (Marseille, France), T. Brown (Boulder, USA), P. Butler (Sydney, Australia), A. Cameron (St Andrews, UK), W. Cochran (Austin, USA), J. Davis (Sydney, Australia), D. Dravins (Lund, Sweden), D. Gray (London, Canada), R. Griffin (Cambridge, UK), A. Hatzes (Austin, USA), A. Irwin (Victoria, Canada), G. Isaak (Birmingham, UK), A. Larson (Seattle, USA), D. Latham (Cambridge, USA), G. Marcy (Berkeley, USA), M. Mayor (Geneva, Switzerland), T. Mazeh (Tel Aviv, Israel), R. McMillan (Tucson, USA), P. Nisenson (Cambridge, USA), D. Queloz (Pasadena, USA), C. Scarfe (Victoria, Canada), R. Stefanik (Cambridge, USA), S. Udry (Geneva, Switzerland), G. Walker (Vancouver, Canada) In addition there will be a number of short oral contributed papers and poster papers. If you wish to present papers in these last two categories, then you will find a form in the second announcement which needs returning to me by April 1. I hope that as many members of Commission 30 as possible will endeavour to come to the colloquium. 4 Triennial commission report The IAU volume Reports on Astronomy comprises the commission reports. As I mentioned, this is a valuable snapshot of the state of research on radial velocities every three years, and one of the major functions of the commission is producing the report. The next report will probably be due in August 1999 for the period 1 July 1996 to 30 June 1999. Our last report comprised the following sections (and authors): Radial velocities of galaxies (Tony Fairall) The Milky Way (Bruce Carney) Star clusters (Jean-Claude Mermilliod) Intrinsic variable stars (Nikolai Samus and Alexei Rastorguev) Spectroscopic binaries (Stephane Udry and Michel Mayor) Precise stellar radial velocities (John Hearnshaw) IAU standard stars (Bob Stefanik) In principle sections of the next report can be written by any of the commission's members. In some ways it may be easier if we decide now on who will undertake this, because the compilers need to be aware of the current literature and make some effort to remain so. So I would like to ask two questions: a) Are there any new sections we should introduce, or old ones change or drop? b) Are there any volunteers who would like to write a section in 1999? Or alternatively, would members like to suggest other individuals whom they consider would be able to write an excellent report section. (NB If the writers of the sections last time are willing to do the same again, please say so!). If we can resolve the issues of the sections and their writers soon, then I think the task will be much easier next year. If I don't have volunterers in the next few months, then I will start inviting people to help by mid-1998. 5 World-wide web If you go to the following WWW URL you will find information on the 11 IAU divisions and 36 current IAU commissions: http://intastun.org/division.html From that web site, you will ascertain that 7 divisions and 17 commissions at present have their own homepages on the Web. Unfortunately Commission 30 is not among them, nor for that matter is Division IX, nor our two sister commissions (9 and 25) in Division IX! That's not a very good record. I have visited some of the other commissions' homepages, and was quite impressed with what they have done. For example, try Commission 26 at http://www.chara.gsu.edu/DoubleStars/intro.html#iau and you will find a wealth of information and links! You will be pleased to know that Dr Chris Sterken (the Division IX president) in Brussels is currently preparing a Web homepage for Division IX. One of my objectives for 1998, hopefully sooner rather than later, is to do the same for Commsiion 30. I therefore welcome your ideas about what should be included and what links are needed. Chris Sterken (email: csterken@vub.ac.be) in Brussels would also welcome ideas for the Division IX homepage. At this stage I have some ideas on topics to be included: Aims and objectives of Commission 30 President, vice-president, organizing committee names and contacts List of members, with areas of interest, and contact addresses List of key codes giving areas of research interests Rules for election of officers Reports of previous Comm. 30 business meetings (at previous General Assemblies) This and previous newsletters Future radial-velocity conferences List of meetings and conferences supported by Commission 30 Link to Division IX homepage Reports on working group for standard stars Report of working group for radial-velocity bibliography and catalogues List of radial-velocity catalogues or compendia Links to galaxy redshift databases List of radial velocity papers (I have doubts that this is useful, because A&A Abstracts or Internet services like Simbad or ADS already do all this). Are there any more ideas? This will take a little time, as first I have to become more familiar with html, but it is a relatively high priority. 6 Working groups I will say very little here about the invaluable work of the commission's two working groups, one on stellar radial-velocity catalogues, led by Hugo Levato in San Juan, Argentina and the other on RV standard stars, led by Bob Stefanik at the Harvard-Smithsonian Center for Astrophysics. Both groups reported to the commission at the Commission 30 meeting in Kyoto in August. When the time comes to complete our homepage on the Web, I hope to have links to both Working Groups, and information about accessing the latest RV catalogues and the latest list of standard stars. Hopefully Hugo and Bob will be able to help me with appropriate information to include. Meanwhile I expect more information on these topics at IAU Colloquium 170 in June this year. 7 List of keycodes for areas of research covered by Commission 30 The list below is a list of keycodes governing different areas of research interest for members of Commission 30. I would like all members to indicate one or several (no limit) of these areas where you have some active research interest. I will include the data in a file of members' areas of interest. As mentioned, I only have the data for half the members at the present time. Please contact me if you have not indicated this information so far. I will send all members the latest membership list, which includes addresses, email addresses and areas of interest. There are about 10 members for which I have no email address, so if you receive this other than by email, it means I need your email address (if you have one). IAU Commission 30 - Radial Velocities Keycodes and Areas of Research. 8 Sept 1997 1 Stellar radial velocities 1.1 early-type stars (earlier than F5) 1.2 late-type stars (F5 or later) 1.3 standard stars, including asteroids 1.4 spectroscopic binary stars 1.5 intrinsic variable stars 1.5.1 pulsating variable stars 1.5.2 asteroseismology, helioseismology 1.6 substellar-mass companions 1.7 highly precise radial velocities 1.8 stars in clusters 1.8.1 open clusters 1.8.2 globular clusters 1.9 kinematics and/or dynamics of stars in the Milky Way 1.9.1 missing mass problems from stellar galactic dynamics 1.9.2 stellar population studies 1.10 stars in satellite galaxies 1.10.1 Magellanic Clouds 1.10.2 other satellite galaxies 1.11 stellar radial velocity catalogues, bibliographies 2 Radial velocities of interstellar gas clouds 2.1 radio-line radial velocities 2.1.1 21 cm velocities 2.1.2 other radio lines 2.2 galactic rotation curve from 21-cm or CO 2.3 missing mass problems in Galaxy from radio radial velocities 2.4 optical radial velocities of interstellar clouds 2.4.1 galactic rotation from optical cloud velocities 3 Radial velocities of extragalactic objects 3.1 radial velocities of galaxies 3.1.1 radial velocities and cosmology 3.1.2 radial velocities and Hubble's constant 3.1.3 large scale mass flows in universe 3.2 galaxy rotation curves 3.2.1 radio 3.2.2 optical 3.3 radial velocities of quasars and active galactic nuclei 3.4 internal motions of clusters of galaxies 3.4.1 galaxies in the Local Group 3.4.2 virial studies of clusters and missing mass problems 3.5 stars and subsystems in galaxies 3.5.1 supernovae 3.5.2 cepheids 3.5.3 clusters 3.6 galaxy radial velocity catalogues, bibliographies 4 Radial velocities in spectral regions other than optical or radio 5 Instrumentation for radial-velocity determinations 5.1 optical instrumentation 5.1.1 photographic 5.1.2 CCD or other solid-state detector 5.1.3 photoelectric (e.g. Coravel) 5.1.4 echelle spectrographs 5.1.5 fibre-feed spectrographs 5.1.6 objective prisms 5.2 radio instrumentation 5.2.1 21-cm instrumentation 5.2.2 instrumentation for microwave molecular lines 5.3 instrumentation for other spectral regions 6 Other 6.1 history of radial-velocity studies ========================================================================== Professor John Hearnshaw Professor of Astronomy and Director of Mt John University Observatory President IAU Commission 30 Dept. of Physics and Astronomy University of Canterbury Private Bag 4800 Christchurch New Zealand. Tel.: +64 (3) 3642533 (direct dial to office) or +64 (3) 3667001 ext. 6533 Fax: +64 (3) 3642469 email: j.hearnshaw@phys.canterbury.ac.nz ===========================================================================