THE NATURE AND EVOLUTION OF DISKS AROUND HOT STARS __________________________________________________ (website at www.etsu.edu/physics/astronomy, designed with Frontpage) LOCATION AND DATE A workshop on disks around hot stars is being planned for 2004 July 7-9, to be hosted by East Tennessee State University in Johnson City, Tennessee (www.etsu.edu), with meetings to be held at the Carnegie Hotel (www.CarnegieHotel.com). MOTIVATION and GOALS Disks are an important, sometimes even dominant, feature of many astrophysical sources, including massive hot stars. Studies of these disks are often constrained by narrow categories of objects, while the key physical principles for understanding the disks in different systems can be quite similar. This workshop is intended to focus discussion on the major outstanding questions surrounding the structure, formation, and evolution of disks around hot stars, and to foster communication between different areas of disk research. With a balanced menu of observational and theoretical presentations, review talks will highlight recent results and key physical principles relating to these topics. In keeping with the workshop theme, substantial time will be allocated for discussion, both in a moderated large group setting and in the casual formation of smaller circles of participants. Posters will be an important component of the meeting, and there will be ample opportunity to examine and discuss poster results. The intended outcome of this event is the synthesis of the latest observational data and theoretical tools to stimulate fresh approaches for this interesting and growing topic of relevance for massive stars. FORMAT We have developed a novel format for the meeting. For each day there will be four invited talks in the morning, with a discussion session in the early afternoon. A "Focus" session will be held later in the afternoon, for which attendance will be optional. Our goal is twofold: first, to provide review talks to summarize the current understanding of hot star disks and set the stage for discussion (the three sessions being "The Properties of Hot Star Disks", "The Star-Disk Connection", and "Magnetic Fields in Massive Stars"). A lunch break will provide a period of time for informal discussion, after which participants will gather for a moderated discussion led by a panel. The Focus sessions are more narrowly defined and are intended to be somewhat tutorial in nature, on the topics of Diagnostic Methods, Modelling Tools, and Optical/IR Interferometry. The workshop format is thus built around a relatively small number of review talks, with plenty of time for interaction, in hopes of achieving a kind of "summer school" flavor. With the number of talks being limited to promote greater opportunities for discussion, poster contributions from attendees will play an especially important role. Our format will allow for greater 'dwell' time to be invested in the posters. We would like participants to come away with a deeper understanding of the key issues and with new ideas for attacking the outstanding questions surrounding hot star disks. We hope to stimulate new collaborations and working partnerships for further progress in this area. SPEAKERS * Jon Bjorkman, University of Toledo Modelling the Structure of Hot Star Disks * Karen Bjorkman, University of Toledo The Observed Properties of Hot Star Disks * Joseph Cassinelli, University of Wisconsin The Effects of Magnetic Fields in Winds and Disks * Janet Drew, Imperial College Winds from Hot Star Disks * Carol Grady, NASA Goddard Evidence of Disks in Herbig Stars * Lee Hartmann, Harvard-Smithsonian CfA The Physics of Circumstellar Disks * Huib Henrichs, University of Amsterdam Magnetism Observed in Massive Stars * Michael Jura, University of California-Los Angeles Dusty Disks Across the HR Diagram * Keith MacGregor, High Altitude Observatory, National Center for Atmospheric Research Generating Magnetic Fields in Early-Type Stars * Georges Meynet, Geneva Observatory The Influence of Rotation for Massive Star Evolution: Principles and Uncertainties * Stan Owocki, Bartol Institute, University of Delaware Dynamical Processes that Drive the Evolution of Hot Star Disks * Thomas Rivinius, Landessternwarte Konigstuhl Links Between Hot Stars and Their Disks FOCUS SESSIONS: ORGANIZERS AND DESCRIPTIONS * Diagnostic Methods - David Cohen, Swarthmore College - Margaret Hanson, University of Cincinnati This focus session will consist of presentations on diagnostic methods used in understanding the nature of disks around hot stars. Methods to be covered include spectral line diagnostics, spectropolarimetry, and high-energy observations. Emphasis will be given to reviewing aspects that exploit upcoming next generation telescopes and instrumentation. Guest speakers will identify questions of current interest and discuss how the different diagnostics can be used to address these issues, including, for example, the distribution of rotational velocities of Be stars, the physical parameters of disks around hot stars, and the role of magnetic fields and winds in hot star disks. Each topic presentation will include a tutorial on the underlying physics of the diagnostics, a discussion of applications to specific open questions of interest to the field, and time for audience participation. Audience members are welcome to share a slide or two, either directly responding to a speaker's presentation or on a related topic. Session organizers will distribute a document in the spring detailing the specific topics of the diagnostics session. If you wish to contribute a slide, please contact D. Cohen (dcohen1@swarthmore.edu) or M. Hanson (hanson@physics.uc.edu). (We will do our best to accomodate impromptu contributions, but only as time permits.) * Disk Modeling - Ken Gayley, University of Iowa - John Porter, Liverpool John Moores University This focus session is intended to provide an opportunity for those interested in disk simulations to share ideas about when various physical effects need to be included, and the corresponding technical challenges. The session will be subdivided into two phases, a "phenomena" phase and an "arts" phase. In the phenomena phase, we will guide a discussion about major physical principles that are most relevant to disk modeling, and the interface between expectations and observations. Optimal allocation of modeling resources requires tradeoffs between accuracy and idealizations, prudently tailored to focus on specific physical effects. This discussion will be aimed at sharing ideas about various possible approaches and the interesting physics they include, involving such things as magnetic fields, viscosity, quadrupole and/or relativistic gravity corrections, and radiative transport of energy and momentum. In the arts phase, we will will provide resources for practitioners interested in including additional physics or improving their techniques. Problems around convergence, instability, and proper boundary conditions will be addressed. * Optical/IR/MM Interferometric Studies of Hot Star Disks - Doug Gies, Georgia State University - Philippe Stee, Observatoire de la Cote d'Azur Time will be equally divided between the topics of interferometry from the optical to millimeter wavelength, the unique challenges and opportunities presented by interferometric studies of circumstellar disks, and a description of current and future instrumentation, facilities, and access. We will start by a short tutorial for people unfamiliar with interferometry but who want to learn about the prospects for new research. The goal of this session will be to highlight how existing problems and questions concerning hot star disks can be addressed with interferometry at optical/IR/mm wavelengths, and to answer questions about available resources and observing opportunities. This session will also give the opportunity to present a few "hot" results through short presentations (3 transparencies maximum). Since place (and time !) will be limited we ask you to contact ASAP Ph. Stee (Philippe.Stee@obs-azur.fr) or D. Gies (gies@chara.gsu.edu) if you wish to give a short presentation. SCHEDULE All events, unless otherwise indicated, will be at the Carnegie Hotel. The *tentative* schedule for the meeting is Tuesday, 6 July 2004: Reception, 5:30pm to 7:30pm, with light snacks Wednesday, 7 July 2004: Review Talk Session I, 8:15am to 10:15am Morning Break, 10:15am to 10:45am Review Talk Session II, 10:45am to Noon Lunch Break, Noon to 1:30pm Discussion Session, 1:30pm to 2:30pm Afternoon Break, 2:30pm to 3:00pm Focus Session A, 3:00pm to 4:30pm Thursday, 8 July 2004: Review Talk Session III, 9:00am to 10:15am Morning Break, 10:15am to 10:45am Review Talk Session IV, 10:45am to Noon Lunch Break, Noon to 1:30pm Discussion Session, 1:30pm to 2:30pm Afternoon Break, 2:30pm to 3:00pm Focus Session B, 3:00pm to 4:30pm Banquet - Dinner to be served at 6:30pm Friday, 9 July 2004: Review Talk Session V, 9:00am to 10:15am Morning Break, 10:15am to 10:45am Review Talk Session VI, 10:45am to Noon Lunch Break, Noon to 1:30pm Discussion Session, 1:30pm to 2:30pm Afternoon Break, 2:30pm to 3:00pm Focus Session C, 3:00pm to 4:30pm Closing Discussion, 4:30pm to 5:30pm Saturday, 10 July 2004: Excursion to Roan Mountain - Hike and Picnic, Departing ~9:30am and Returning ~3pm COSTS All fees are to be paid in US Dollars (see the following section on REGISTRATION for payment options) Registration fee - $200 This fee contributes to the meeting facilities, a copy of the workshop proceedings (to be published in the ASP Conference Series), the reception, and services for the breaks and lunch for each of the three days. Accommodation - The organizers would like all attendees, if possible, to book accommodation at the Carnegie Hotel, the host site for the meetings. The Carnegie is a 4-star hotel adjacent to the ETSU campus. It has a pool, exercise room, and even a spa, plus a dining room, bar, casual setting rooms, and an adjacent cafe. Having everyone together at the same location will enhance interactions, both professionally and socially. The meeting rate for guest rooms will be about $100 per night (still being finalized). The web page for the Carnegie Hotel is www.CarnegieHotel.com The phone number for reservations is +USA 423 979 6400 Their fax number is +USA 423 979 6424 Please mention that you will be an attendee of the astronomy workshop to get the proper room rate. Banquet fee - $40 The Banquet for the workshop will be held on the evening of Thursday, 8 July. Dishes will include a vegetarian option. Entertainment will be provided. Roan Mountain Excursion - $25 A hike and picnic at the Roan Mountain State Park, somewhat east of Johnson City, is planned for the Saturday after the meeting (July 10) for any who are interested. Roan Mt. is host to rhododendrons that should be in bloom in July. The park is less than an hour's drive from Johnson City. Departing in the morning, there will be a picnic and plenty of time to wander and enjoy the scenery before returning in the late afternoon. * If you wish to attend the meeting and are in need of financial * * assistance, we anticipate having some limited resources to help. * * Contact Richard Ignace (ignace@mail.etsu.edu) with your request. * REGISTRATION A reminder that only poster contributions will be accepted. The rationale is that by limiting the number of talks, discussion opportunities will be maximized. This also means that since review talks will only be in the morning, there will be more opportunities to look over poster results. Posters will be displayed throughout the 3 day meeting. Registration is a two-part process. If you intend to present a poster contribution, then the first step is to submit a title and abstract by *** 1 April 2004 *** Note that each registrant is permitted to be the first author on one poster only. To submit a poster contribution, send your title, author list, and abstract to hotstars@mail.etsu.edu. This should be plain ascii text; however, any special characters should be typeset in latex. Please place the text 'poster' in the subject line. The second step is to register for the meeting, which requires payment of fees described above. (If you do not intend to present a poster, then you simply need to register for the meeting. However that the registration fee is the same with or without a poster contribution.) Online registration can be reached via the link at the workshop website, or directly at faculty.etsu.edu/dyed/astronomy_workshop_registration.htm Payment of fees can be done online, by phone, or by fax. Payment will be handled by the ETSU Department of Professional Development (phone numbers +USA 800 222 3878 or 423 439 8025). Payment must be in US Dollars, and can be made by credit card, cheque, or purchase order. Registration must be made by *** 1 May 2004 *** Attendance will be capped, because of space limitations at the Carnegie. Registration may close before the 1 May deadline because of space restrictions. In the event of late registration, the fee will be $250. QUESTIONS For questions or more information, please direct all correspondence to the workshop organizers at hotstars@mail.etsu.edu. SOC Richard Ignace, Principal Organizer, East Tennessee State University Karen Bjorkman, Co-Organizer, University of Toledo Joseph Cassinelli, Co-Organizer, University of Wisconsin Kenneth Gayley, Co-Organizer, University of Iowa LOC Mark Giroux, East Tennessee State University Richard Ignace, East Tennessee State University Donald Luttermoser, East Tennessee State University Beverly Smith, East Tennessee State University