Be STAR NEWSLETTER
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ISSN Be STAR NEWSLETTER NUMBER July EditorinChief Technical Editor Geraldine J Peters Douglas R Gies email g jp etersmucenuscedu email giescharagsuedu Space Sciences Center Center for High Angular Resolution Astronomy University of Southern California Department of Physics and Astronomy University Park Georgia State University Los Angeles CA Atlanta Georgia Tel Tel FAX FAX Be Star Newsletter Contents Editorial G Peters Working Group Matters Working Group News Myron Smith Contributions Preliminary results on photometric variability of B and Be stars with HIPPARCOS AM Hub ert M Flo quet AE Gomezand V Aletti V Cas the optical comp onent of the Be Xray transient U I Negueruela S J Unger and P Ro che A Sp eckle Survey of Southern Be Stars B D Mason T ten Brum melaar D R Gies W I Hartkopf and M L Thaller Observations of H Emissions of Be Stars with an Ob jective Prism and CCD Camera E Pollmann Whats Happ ening An exp erimental ephemeris of the emission outbursts of Centauri observational verication requested Th Rivinius S Ste D Baade O Stahl B Wolf and A Kaufer Rep ort on the MultiSite and MultiSatellite Campaign on Cas M Smith Progress on Mo deling NRPrelated Prole Variations D Gies SONGNews Be Disks Resolved D Gies Preprints Received Bibliography Meetings LaTeX Template for Abstracts The Be Star Newsletter is produced at and nancial ly supported by the Georgia State University Department of Physics and Astronomy The electronic version is available on the World Wide Web httpwwwcharagsueduBeNewsintrohtml or by anonymous ftp ftp charagsuedu cd BeNews Be Star Newsletter EDITORIAL There is always keen interest in the rst data from a new spacecraft In this nd issue of the Be Star Newsletter we include a rep ort on some initial results on the nature of photometric variability in B and Be stars from the HIPPARCOS satellite Esp ecially interesting is a rather sp ectacular photometric outburst in Cyg Now Cas was not only the rst Be star to b e discovered but more researchers have studied this star in the past years than any other Be star it is said that if one works on Be stars long enough shehe will eventually write one or more pap ers on Cas Well new data from the ASCA RXTE and HST spacecraft have revealed a mo dulation in its Xray FUV ux on a time scale consistent with its rotation p erio d Some implications of this are discussed in WHATS HAPPENING There are also new results from groundbased telescop es rep orted in this issue apparent quasip erio dic b ehavior for the emission line outbursts in Cen complex H He emission line variations in the disk of the Be star in the Xray binary V CasU and the recent discovery of ve new sp eckle binary Be stars In another contribution the promise of amateur equipment for detecting cyclic and transient H emission line variability in Be stars is clearly demonstrated We also call attention to the recent impressive progress on mo deling NRP and the geometries of Be star disks and include our newly expanded bibliography of recent pap ers on active B stars and related ob jects of p ossible interest to the community Traditionally the Newsletter has b een published at irregular intervals with a frequency governed by the number of contributions Usually two issues a year are pro duced Starting with Issue No we would like to adopt a more rm schedule for publication We prop ose continuing a semiannual publication frequency with issues nalized in June and December The cuto date for contributionsabstracts for Issue will b e November Contributions should b e sent by electronic mail to gjpetersmucenuscedu and giescharagsuedu As mentioned in the last Newsletter we are now requiring that abstracts b e sub mitted as LaTeX les A template for their preparation is provided in this issue and can also b e downloaded from our web site Illustrations should b e sent by Email as a PostScript le If it is not p ossible to transmit your contribution electronically please send or fax a dark cameraready copy Again we wish you a happy pro ductive summer and encourage you to announce your discoveries and express new ideas in Issue No of the Be Star Newsletter Gerrie Peters EditorinChief Be Star Newsletter WORKING GROUP MATTERS Working Group News Hello Fellow Members of IAU WG On Active B Stars IAU Meeting This is the year of the triennial IAU GA meeting which will b e held in August in Kyoto Japan Thanks to the work of Mike Jerzykiewicz we have Ro om H reserved at am on August th My term as your WG Chairman will come to an end at that time Unfortunately I will not b e able attend the GA myself but John Percy has kindly agreed to preside over the meeting Please send me agenda items that might o ccur to you and I will forward them to John A New International Meeting on BBe Stars years since the last international Symp osium on BBe stars at It has already b een JuanlesPins France and it is certainly time to take sto ck of the many advances in our eld since that convocation with a new meeting This winter the Universities of Valencia and Alicante Spain have issued an invitation for a meeting to b e held there in the next year or two in Alicante The OC has accepted this invitation with thanks and appreciation to the hosts for their patience in awaiting our acceptance The next meeting will b e held in Alicante Spain on or ab out June We will seek IAU sp onsorship of a collo quium or symp osium Our tentative date will give us nearly a year to prepare a prop osal to the IAU I have asked Juan Fabregat who advanced this invitation to chair and form the LOC Our B star OC has voted on ve members of the SOC in addition to Fabregat and the SOC elected a Chair The elected members of the SOC for the Spain meeting are J Fabregat Spain Chair LOC M Smith USA Chair SOC E Kambe Japan S Ste Czech Republic J Bjorkman USA A Fullerton Germany It is likely that additional members of the SOC will b e app ointed as the theme and title for the meeting b ecome more dened I will b e putting out a call to the WG membership very so on requesting ideas for a title I hop e by the time of the Kyoto meeting to have a title for our Kyoto conclave to conrm Elections On a related matter I now op en the electronic o or for three nominations of WG members who with me will b e retiring from these p osts this summer These are Rens Waters Catharine Garmany Petr Harmanec and Myron Smith IAU Commission No will app oint a replacement for Katys p osition Any other member of our Be Star Newsletter WG who also b elongs to the IAU is eligible We will follow the example set three years ago by Luis Balona in having an election by electronic ballot Please indicate Nomination in the sub ject header and send nominations to the BEIAU account listed b elow Following the reconstitution of the WG we will elect a new Chair from this group I hop e to have all electoral matters settled b efore our meeting Co op erative Search for Light Transients with Amateurs My nal item is to inform you of an initiative started in North America b etween pro fessional and amateur astronomers that we hop e can spread to many other countries The idea is to put the search for optical photometric transients of classical Be stars on the less than the accidental fo oting that they have had up until now Many of you will recall Luis Balonas publishing of the ickering b ehavior in the light curve of CMa during an outburst in In a new pap er in AA Suppl the Hvar Observatory group Pavlovski et al have shown that even bright Be stars can undergo sudden bright or faint excursions in their light curves Smith et al now have a pap er in press see Abstracts in this issue in which FUV sp ectrophotometry shows a ringing with a p erio d of hrs There is a general feeling that if a pattern could b e discerned from a p opulation of such so far accidentally discovered events it could lead to a b etter understanding of the instabilities resp onsible for the outbursts in classical Be stars Toward this end I have formed a liaison committee Smith Balona Percy to oversee activity b etween amateur and professional astronomers The basic idea is to combine the discovery of such events by a few professional scouts with follow up work hours or a night later by a rapidresp onse force Thus far we have had a candidate for scout step forward Dr Elaine Halb edel of Corralitos Observatory in Las Cruces NM In addition we have placed a call to the AAVSO asking for help This has netted three parttime volunteers R Fried R Wasatonic R Zissell as well as an amateur sp ectroscopist in Germany Ernst Pollmann see Pollmanns article later in this issue If you are interested in joining this eort or if you know of amateur astronomers in your area with PEP equipment and capability of observing with mag please errors please let me know Best wishesClear Skies Myron A Smith Chair of IAU WG on Active B Stars email BEIAUiuegtcgsfcnasagov Be Star Newsletter CONTRIBUTIONS Preliminary results on photometric variability of B and Be stars with HIPPARCOS A M Hub ert M Flo quet A E Gomezand V Aletti Observatoire de ParisMeudon DASGAL URA du CNRS F Meudon Cedex France Rapid and midterm variability has b een searched in a sample of B and Be bright stars V with photometric measurements by HIPPARCOS This astro metric satellite of the Europ ean Space Agency was launched in August and