The European Extremely Large Telescope ______________________________________ Industrial invitees - Bart Snijders, Snijders@TPD.TNO.NL, Ben Braam, Braam@TPD.TNO.NL - Serguei P. Beloussov, Alexey P. Patrikeyev, Nadezhda V. Markelova, LZOS, lzos@comail.ru - Jean Espiard, jeanespiard@hotmail.com - marc.cayrel@sagem.com, roland.geyl@sagem.com - Peter Koehler; p.koehler@zeiss.de, Wolfgang Heilemann, heilemann@zeiss.de - Frank Carbone, Kodak, carbone@dsalph02.ias.kodak.com - Mrs Eymanns, Corning, EymannsN@corning.com - Michael Voevodsky, Hextek, mvoevodsky@hextek.com - Pierre Deny, Boostec, pdeny@boostec.com - Emmanuel Sein, Astrium, Emmanuel.SEIN@astrium-space.com - Christophe DAUGNY, CSP France, csp.france@wanadoo.fr - Didier ROZIERE, Fogale, d.roziere@fogale.fr - Mr. Fappani, Seso, df@seso.com _______________________________________________ Aim of the meeting This meeting will gather together the groups in Europe that are developing designs of Extremely Large Telescopes in order to define an OPTICON-sponsored request for a EU commission RTD within Framework 6. The aim of the RTD is to realize a Phase A study for the next generation european telescope. We envision that this will be achieved by studying various options, analyze the technical and scientific tradeoffs, obtain industrial feedback on feasibility and cost issues, identify possible sites etc. We realize that this will in part overlap the activities carried out at various institutions, but we see this as an advantage: as the proposed goal is to come up with a design that fulfils the science requirements with the minimum cost, it is important that many options are investigated and that, as far as possible, industrial feedback be obtained on their feasibility (with a preference, at least in the first instance, to design-independent subsystems, e.g. blank fabrication, mechanical components, actuators, phasing techniques etc). To achieve this, we propose to organize the RTD around a few main activities, each with a set of Work PAckages that study in depth the various components. A Steering Committee could also be created to supervise the developments and to assess periodically the status of the study. As a sugestion (to be discussed/improved/ changed at the meeting) a possible Work Breakdown Structure could consist of: 0. RTD overview This could be carried out by the Steering Committee 1. Science Case Determine the level one requirements for the ELT design based on the scientific case (this is the present Opticon WG charter) 2. Optical aspects Analyse various possible designs, determine tradeoffs, costs etc. WPs could include spherical primary designs, aspheric primary designs, segmentation 'strategy' (size, fabrication, material...), phasing issues, active optics options, atmospheric dispersion correction, wavefront sensors, field stabilization, adaptive secondaries etc 3. Mechanical design Define the requirements of mechanics, both in a general (i.e. design independent) way and specifically to optical designs. WPs could include geneal topics (materials, basic components, wind studies, dymanic performance) as well as design-specific topic (machanical design for optical design X etc) 4. Control aspects and Operations Define the options for control needs of ELTs (requirements, solutions) as well as the interaction with science and technical operations. WPs could include enabling experiments, definition of control loops, determination of computer requirements, operations models, maintenance requirements (e.g. how this affects the final design) 5. Adaptive optics A critical aspect of ELTs is their ability to achieve the diffraction limit, as required by the science case. Many activities are underway (including an RTN to which many OPTICON members already participate). WPs may include wavefront sensing options, MCAO, laser guide stars vs natural guide stars, computer requirements, reconstruction techniques etc. 6. Instrumentation Determine the instrumentation requirements (and challenges...) based on the science case 7. Site selection World-wide search for the best site. A WG on this has been already set up, and could be subsumed in our RTD 8. System overview System engineering, end-to-end model, "integration" of requirements. Eventually, organize and edit the final document. Proposed agenda for meeting Friday: 14:00 Introduction (G. Gilmore) 14:10 Framework 6 (Elena Righi-Steele, European Commission representative) 14:35 Science case (R. Gilmozzi or T. Hawarden) 15:00 Status of current studies 15:00 Euro50: design overview (A. Ardeberg) 15:20 Euro50: technical issues (T. Andersen) 16:00 Break 16:30 Status of current studies (cont'd) 16:30 OWL and the ESO long range plan (R. Gilmozzi or A. Renzini) 16:45 OWL: design status (P. Dierickx) 17:05 OWL: mechanics (E. Brunetto) 17:15 OWL: MCAO simulations (M. Le Louarn) 17:25 OWL: MCAO demonstrator (E. Marchetti) 17:40 Interaction with industry (P. Dierickx or JL Beckers) 17:55 Site selection (M. Sarazin) 18:10 ELT instrumentation (G. Monnet) 18:30 Adaptive Optics for ELTs (R. Ragazzoni) 19:00 Dinner Saturday 09:00 Discussion (R. Gilmozzi and G. Gilmore) 15:00 Meeting conclusions (G. Gilmore and/or R. Gilmozzi) 15:30 End of meeting The next OPTICON partners meeting and the OPTICON Extremely Large Telescopes (ELT) working group meeting will be hosted at Tuorla Observatory (www.astro.utu.fi) on May 3rd and 4th 2002. Tuorla Observatory is located 15 km East of Turku, in Southwestern Finland. The local host is Leo Takalo. Turku can be reached by plane from Copenhagen, Stockholm or Helsinki. The easiest way is via Helsinki, since there are several daily flights between these cities (see www.finnair.com for flights or ask your local travel agent). There are also frequent buses (once per hour) from the Helsinki airport directly to Turku. The bus ride takes 2.5 hours and costs about 30 Euros, tickets can be bought from the bus driver. From Turku airport one can take a bus or a taxi to the town center (taxi fare is around 20 Euros). In Turku, we have reserved a number of rooms at the hotel Centro for the participants. Room rates are 66 Euros in a single room and 75 in a double room per night. Hotel Centro. Address: Yliopiston katu 12A. Phone: 358-2-4690469 Fax: 358-2-4690479 Web-page: www.centrohotel.com If you make your own arrangements with this hotel, tell them that you belong to the Tuorla Observatory group. Other possible hotels can be found e.g. from the following WEB-pages: www.sokoshotel.fi/englis/hotellit/btku.html phone: 358-2-3373800 www.scandic-hotels.com Phone: 358-2-33632210 All these hotels are located near the town center in Turku. The room rates in the hotels vary from weekdays to weekends. During weekends (from Friday to Sunday) they range from 60 to 90 Euros in a single room. To make your room reservations in any of these hotels you can either contact Leo Takalo (takalo@astro.utu.fi) or make your own eservations. We need to know in which hotel everyone is staying in order to arrange the transportation from Turku to Tuorla. In all matters concerning the arrangements at Tuorla you can contact Leo Takalo at: email: takalo@astro.utu.fi phone: 358-2-2744258 fax: 358-2-2433767 Leo O. Takalo, Tuorla Observatory, 21500 Piikkio, Finland Please also confirm your attendance to Karen Disney (karen@ast.cam.ac.uk) The local weather site is http://at8.abo.fi/cgi-bin/get_weather