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Changes between Version 374 and Version 375 of AstroTechTalk


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Timestamp:
11 Oct 2018, 08:16:51 (6 years ago)
Author:
Ralph Hofferbert
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  • AstroTechTalk

    v374 v375  
    2727|| '''28.09.2018[[BR]](11hrs, MPIA Hoersaal)''' || '''Prashant Pathak (ESO)''' || '''Closed-loop correction of  atmospheric dispersion for high-contrast coronography and astrometry'''[[BR]][[BR]]On ground-based telescopes employing adaptive optics (AO) systems,  atmospheric dispersion compensation is essential to deliver high-quality  imaging, and critical for coronagraphy and high-precision astrometry.  Imperfect compensation by  an atmospheric dispersion compensator (ADC) can be addressed with a  high-precision on-sky measurement of residual dispersion in a  closed-loop control scheme. [[BR]][[BR]]In this talk, Prashant Pathak will present a focal plane  based technique, which utilizes the chromatic scaling of speckles  to measure residual dispersion (atmospheric and optical) in the final  science image. The residual dispersion can be accurately measured and  subsequently corrected in a closed-loop control. On-sky residual  dispersion of < 1 mas across H-band was demonstrated,  which reduced from 8.4 mas before closing the loop.[[BR]][[BR]]Presentation: English[[BR]][https://svn.mpia.de/trac/gulli/att/raw-attachment/wiki/AlteVortraege2018S2/2018-09-28_HCI_ESO.pdf Slides: English][[BR]]Questions: German, English ||
    2828|| 05.10.2018 || || ||
    29 || '''12.10.2018[[BR]](11hrs, MPIA Hoersaal)''' || '''Hans-Ulrich Kaeufl (ESO)''' || '''NEAR - Planet search around Alpha Centauri with VISIR[[BR]]'''[[BR]]ESO, in collaboration with the Breakthrough Initiatives, modifies the  Very Large Telescope mid-IR imager (VISIR) to further boost the high  dynamic range imaging capability this instrument has, by adding a  dedicated coronagraph. This enables a meaningful search for potentially habitable planets  around both Alpha Cen1 and 2. Meaningful here means, achieving a  contrast of ~10^-6^ within ~0.8arcsec from the star while maintaining  basically the normal sensitivity of VISIR. For risk mitigation all components are being tested and qualified under  realistic conditions in the lab at ESO headquarters before integration  into the instrument.  [[BR]] [[BR]]Hans-Ulrich Kaeufl will give an overview of [[BR]]- the optical changes to VISIR [[BR]]- the implementation of wave front sensing [[BR]]- the Dicke switch (fast chopping for noise suppression) design and laboratory testing [[BR]]- the Annular Groove Phase Mask design and laboratory testing [[BR]]- non common path error control with a ZELDA mask [[BR]]- sensitivity and contrast estimates [[BR]]- data flow and analysis [[BR]]- the overall project status, plan and outlook [[BR]] [[BR]]Needless to say that this project is of critical interest for future  infrared instrumentation at the next generation of extremely large  telescopes aiming at surveying the solar neighbourhood for terrestrial  planets by detecting and characterizing them based on their mid-IR  fluxes. Therefore some emphasis will be put on the verification of the  novel chopper system, the Dicke switch.[[BR]][[BR]]Presentation: German[[BR]][https://svn.mpia.de/trac/gulli/att/raw-attachment/wiki/AlteVortraege2018S2/2018-10-12_NEAR.pdf Slides: English][[BR]]Questions: German, English ||
     29|| '''12.10.2018[[BR]](11hrs, MPIA Hoersaal)''' || '''Hans-Ulrich Kaeufl (ESO)''' || '''NEAR - Planet search around Alpha Centauri with VISIR[[BR]]'''[[BR]]ESO, in collaboration with the Breakthrough Initiatives, modifies the  Very Large Telescope mid-IR imager (VISIR) to further boost the high  dynamic range imaging capability this instrument has, by adding a  dedicated coronagraph. This enables a meaningful search for potentially habitable planets  around both Alpha Cen1 and 2. Meaningful here means, achieving a  contrast of ~10^-6^ within ~0.8arcsec from the star while maintaining  basically the normal sensitivity of VISIR. For risk mitigation all components are being tested and qualified under  realistic conditions in the lab at ESO headquarters before integration  into the instrument.  [[BR]] [[BR]]Hans-Ulrich Kaeufl will give an overview of [[BR]]- the optical changes to VISIR [[BR]]- the implementation of wave front sensing [[BR]]- the Dicke switch (fast chopping for noise suppression) design and laboratory testing [[BR]]- the Annular Groove Phase Mask design and laboratory testing [[BR]]- non common path error control with a ZELDA mask [[BR]]- sensitivity and contrast estimates [[BR]]- data flow and analysis [[BR]]- the overall project status, plan and outlook [[BR]] [[BR]]Needless to say that this project is of critical interest for future  infrared instrumentation at the next generation of extremely large  telescopes aiming at surveying the solar neighbourhood for terrestrial  planets by detecting and characterizing them based on their mid-IR  fluxes. Therefore some emphasis will be put on the verification of the  novel chopper system, the Dicke switch.[[BR]][[BR]]Presentation: German[[BR]][https://svn.mpia.de/trac/gulli/att/raw-attachment/wiki/AlteVortraege2018S2/2018-10-12_NEAR.pdf Slides: English][[BR]]Questions: German, English ||
    3030|| 19.10.2018 || || ||
    3131|| 26.10.2018[[BR]](11hrs, MPIA Hoersaal) || Armin Huber || Slide-Show - Life at VLT ||
     
    4242'''Preview:'''
    4343
    44 xx.xx.2019 - Speaker: Topic
     4411.01.2019 - Carlos Correia (LAM): AO Control
    4545
    4646'''Postview:'''