The AstroTechTalk (ger) offers a place to discuss, for all interested colleagues and especially for the technical departments, the project leaders, the administration and the scientists as the ultimately users:

• status of instrumentation projects
• scientific tasks and features of the instruments in construction or planned
• new possible involvements
• technical innovations and developments
• technical problems and their solutions
• logistical problems and their solutions
• how to improve operation and observation
• project standards.

Time: Always Fridays 11:00 - 12:00

Location: Hörsaal

Outline:

• Announcements (news, visitors, etc.) (mainly in German)
• Talk of about 30 min about a selected topic (German or English, will be announced)
• Follow up discussion and questions (German or English, depending on the speaker)

Please send proposals for talks via e-mail to: gaessler, hofferbert - or also available in room 021 or 211.

Date	Speaker	Topic
12.09.2014	Martin Kürster
19.09.2014	Ralf-Rainer Rohloff	Precision metal optics over a large temperature range Since long, metal optics are an important part of astronomical instruments. Often diamond turned mirrors of aluminum (Al6061) are used. But it is difficult to polish aluminum. Therefore, the mirror is coated with Nickle Phosphor layer, which can be polished more easily. This is very important at shorter wavelength. But the mirrors deform with temperature changes because of the different coeffient of thermal expansion between aluminum and NiP. Ralf-Rainer will tell us about a collaboration between MPIA Heidelberg and IOF Jean, which developed and tested a new material to minimize the temperature related deformation of such mirrors. The material consists of an aluminum silicate, which has a coefficient of thermal expansion close to NiP. Thus, the deformation could be reduced drastically. But now the work just started. Is it possible to built a mirror of this material? Does the material change with time? The best answer would be the study could show that such mirror can be built and are stable over time! Talk: German Slides: English Questions: German, English
26.09.2014
03.10.2014	--	Tag der deutschen Einheit
10.10.2014
17.10.2014
24.10.2014
31.10.2014
07.11.2014
14.11.2014	Stefan Meister	Azubipreise 2011-2014
21.11.2014	?? Jörg-Uwe Pott	?? MICADO
28.11.2014
05.12.2014
12.12.2014
19.12.2014
26.12.2014	--	Weihnachten