Proceedings -- Programme -- Rationale -- Timeliness -- Sessions -- Speakers
 

Proceedings

We publish the papers in a dedicated issue of Astronomische Nachrichten (AN) without page charges. Each paper will be refereed and treated as a regularly submitted paper, just that it appears in a dedicated issue. The AN Editorial Board have generously reserved 80-100 journal pages in an issue of Volume 325, to be published early in 2004. We thus have to impose page limits of 4 pages for oral contributions, and 1 page for poster papers. AN provides full electronic access including ADS/CDS cross referencing including an abstract service.

Authors should prepare their papers using the AN LaTeX templates which should be downloaded from here as a gzipped tar file. Alternatively you may request the files by email to aschwope@aip.de.

Once papers have been prepared they should be emailed as PDF or gzipped Postscript files to the Editors (see addresses below) for refereeing. We will probably call upon meeting participants to act as referees in some instances, so please be prepared to help us out here!

The deadline for receipt of manuscripts by the Editors is 30 September 2003.

Once your paper has been refereed and the final version accepted, the source files should be uploaded to the journal as detailed in the Instructions for Authors on the AN web page.

We hope that those of you who wish to purchase the relevant volume of the journal have already placed your orders with Axel Schwope at the meeting. If by any chance you missed out in Sydney, please contact Axel to place your order and arrange payment.

In addition, a set of extended abstracts will be published in the official record of the General Assembly, in "Highlights of Astronomy". Information on how this will be done will be posted here as soon as we can find out for ourselves!

Andrew Collier Cameron <acc4@st-and.ac.uk>
Axel Schwope <aschwope@aip.de>
Sonja Vrielmann <stch307@hs.uni-hamburg.de>
 

Programme

JD9-I:   Thursday July 17  (Harbourside Meeting Room 4)

15:30 - 16:00  Posters / Coffee Break

16:00 - 16:15  Differential rotation of stars (Pascal Petit)
16:15 - 16:30  Roche tomography of CV secondaries (Chris Watson)
16:30 - 16:45  Doppler tomography of Algols (Mercedes Richards)
16:45 - 17:00  Tomographic studies of exoplanet atmospheres (Andrew Collier Cameron)
17:00 - 17:15  Echo mapping of active galactic nuclei (Brad Peterson)
17:15 - 17:30  Echo mapping of X-ray binaries (Keith Horne)
 

JD9-II:  Monday July 21  (Promenade Meeting Room 3)

10:30 - 11:00  Posters / Coffee Break

11:00 - 11:15  Doppler mapping of magnetic CVs (Axel Schwope)
11:15 - 11:30  Stokes imaging of magnetic CVs (Stephen Potter)
11:30 - 11:45  Selected magnetic CVs (Gaghik Tovmassian)
11:45 - 12:00  Few-projections astrotomography (Michail Agafonov)
12:00 - 12:15  Tomography of stellar non-radial pulsations (Svetlana Berdyugina)
12:15 - 12:30  The atmosphere of V471 Tau (Fred Walter)

Proceedings -- Programme -- Rationale -- Timeliness -- Sessions -- Speakers

Scientific Rationale

Astrotomography takes advantage of the fact that we can observe an object from different angles. A series of n-dimensional images of a full cycle can be fed into a computer in order to yield a (n+1)-dimensional picture of the object. These pictures can be further analysed and compared to existing theoretical models. Tomography opens a wealth of new information on the object under investigation.

In the case of Cataclysmic Variables, we have verified the presence of accretion discs and streams and of thick disc rims shielding the donor star surface from irradiation by the hot inner disc. We have revealed the existence of tidally induced spiral shock waves in accretion discs. We have measured the magnetic field strength, the angle of the magnetic poles of Polars, disc radii, disc temperatures and surface densities of Dwarf Novae and Nova-likes. We find that the disc must have a sandwich like structure, however, details are still uncertain. But the quiescent state of dwarf novae as well as the high and low states in nova-likes and polars are not fully understood. We expect a comprehensive picture to be developed in the near future to which such a discussion will contribute tremendeously.

Echo mapping, or reverberation mapping, was developed to analyze the structure and velocity field of the microarcsecond-scale emission-line regions in active galactic nuclei or quasars via time delays between continuum and emission-line variations caused by reflection and reprocessing of radiation. It is also beginning to yield information on accretion-disc structure. To date, application of this technique has yielded sizes of the emission-line regions and demonstrated radial ionization stratification, and has led to measurements of the masses of the supermassive black holes that power these sources. The next generation of reverberation mapping experiments, using dedicated facilities, will resolve finer-scale structures, such as temperature-radius profiles, and settle definitively the origin of the emission-line gas and clarify how quasars are fueled.

The analysis of cool stars has revealed not only that their surface are covered with large cool spots but also with changing magnetic field patterns, and that both are affected by surface differential rotation similar to what we see on the Sun. However, only Doppler tomography with a baseline of several years will reveal if these stars undergo solar-type cycles. We expect to hear first results at the proposed Joint discussion.

We propose to discuss these and further new results from research areas in Astrotomography, e.g. Zeeman-Doppler Mapping, Roche Tomography and Doppler tomography of Algols and W UMas, during this joint discussion.

Proceedings -- Programme -- Rationale -- Timeliness -- Sessions -- Speakers

Timeliness

• Several new instruments (ESPaDOnS, ULTRACAM, PEPSI,HARPS, Kronos), some of them specifically designed for astrotomography, in combination with 10-m class telescopes will be fully operational by that time. We expect first results of unseen quality and resolution as well as discovery of new features, e.g. magnetic fields in new types of targets, and objects, e.g. exo-planets, to be presented at the time of the GA.
• In the search for exo-planets tomographic methods will be extremely useful. Albedo spectra of Hot Jupiters can be measured using the planet's orbit velocity rather than angular resolution to separate the star and planet light. Current upper limits with 4m telescopes require an albedo less than that of Jupiter, ruling out atmospheric models with relatively high reflective cloud decks. First detections with 8m telescopes are likely to be presented.
• By then we will have a great enough data base to draw statistical conclusions about differential rotation and will be able to present implications on the associated physical processes (e.g. feedback effect of magnetic fields on the dynamics of convective zones). Furthermore, new telescopes allow us to study chromospheric activity on stars only slightly more active than the Sun. This increases dramatically the foundation for physical models making them more reliable.
• The recent direct magnetic field detections at the surface of some classical T Tauri stars should enable us to obtain a rough idea of the magnetic field topology on these objects and thus to examine in some detail how adequate the existing models of magnetised accretion/ejection processes frequently invoqued for pre main sequence stars are in this context.
• By then we will have gathered enough maps of accretion discs and streams in cataclysmic variables in order to draw statistical conclusions on accretion disc physics in general. This will then also allow us to identify exotic objects and discuss how they are likely caused. One example is WZ Sge's premature outburst in August 2001 which by that time will be well analysed.
• We will have first radial temperature measurements for several AGNs which can be compared to existing theoretical models and first map derived for NGC 7469. Furthermore, we expect to have first analyses of physical parameter reverberation mapping studies of AGN.
• We expect a report on the first X-ray tomography.
• While during the Astrotomography workshop in Brussels the exchange between people working with different objects but using similar or complementary methods was the main contribution, we expect to see the practical results of this exchange during the proposed JD.

We need to discuss how to apply the tomographic methods in order to extract maximum reliable informations about the objects. This holds for any other new technique to be developed by then and any new type of object to be studied with tomographic methods.

Scientific Sessions

Thursday July 17 (JD9-I):
The official JD09 session on "Astrotomography" and will be held on July 17 from 2pm to 5:30pm in Harbourside Meeting Room 4 (capacity 200).  There will be a 30-minute  break for coffee and posters between the sessions from 3:30pm  to 4:00pm.

Monday July 21 (JD9-II):
Thanks to the generosity of Paula Szkody, President of Commission 42, we will have access to two additional sessions during the "Commission 42 Working Group on Accretion" workshop on July 21 from 9am to 12:30pm in Promenade Meeting Room 3 (capacity 65).   There will be a 30-minute  break for coffee and posters between the sessions from 10:30am  to 11:00 am.
 

List of Speakers

List of Poster Presentations

CV=Cataclysmic Variable
 

Scientific Organizing Committee:
         R. Baptista (Brazil), A. Collier Cameron (UK, co-chair), V. Dhillon (UK), J.-F. Donati (France), E. Harlaftis (Greece), L. Morales Rueda (UK, co-chair), B. Peterson (USA), N. Piskunov (Sweden), M. Richards (USA, Chair), A. Schwope (Germany) & S. Vrielmann (South Africa)

Editors of Proceedings:
         Andrew Collier Cameron (Chief Editor), Axel Schwope, & Sonja Vrielmann

Contact Address:
         Mercedes Richards, Penn State University, Dept. of Astronomy & Astrophysics, 525 Davey Lab, University Park, PA 16802, USA; Tel: (814) 865-0150, Fax: (814) 863-2842, e-mail: mrichards@astro.psu.edu
 
 

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