Astronomical Spectroscopy with Electron-Multiplied CCDs (EMCCDs)
Key Workshop Objective
- Understand the merits and limitations of EMCCDs in astronomical spectrographs and how to optimize their use
Date and Time |
July 28, 2015 |
Location: |
Hameetman Auditorium |
Cahill Center for Astronomy and Astrophysics, Caltech |
Workshop Goals
- 1) Understand the practical performance of current EMCCDs in astronomical applications.
- 2) Identify scientific opportunities uniquely enabled by large format EMCCDs.
- 3) Explore the design space of spectrograph (and mission) architectures suitable to exploit EMCCD advantages.
- 4) Communicate shared interests and build a richer community of instrumentalists knowledgeable with EMCCD technology.
Participation
Organizing Committee: R. Dekany, E. Hamden, R. Jensen-Clem, G. Kyne, N. Konidaris, C. Shapiro (JPL) |
Attendees: R. Dekany, E. Hamden, G. Kyne, P. Morrissey, C. Shapiro, G. Hallinan, E. Kirby, R. Smith, S. Nikzad, C. Martin, J. Cohen, C. Steidel, K. Wallace, G. Hallinan, L. Harding (JPL), L. Hillenbrand, E. Kirby, N. Lingner, T. Goodsall (JPL), D. Mawet, J. Feliciano, J. Milburn, J. Fucik, E. Bellm, D. Neill |
Cannot attend: R. Demers (JPL), R. Riddle |
Agenda (draft)
* Pre-Session (8a) : "EMCCD 101” tutorial session* -- Roger Smith
* Special breakfast (9a)
* Morning Sessions (start at 9:30a) - N. Konidaris, Session Chair
- Scientific advantages and disadvantages of EMCCDs for spectroscopy (1 hour) - Nick Konidaris
- (Sensitivity / architecture flexibility / operations / integrating modes / dynamic range / data processing & management / calibration / etc.)
- Technology roadmap / future devices / commercial intentions (TBC)
- Commercial EMCCD camera comparison (10:30a) - Rich Dekany
- Real-world experience with EMCCDs in astronomy (11p)
- CHIMERA / WFIRST testing - Gregg Hallinan (confirmed) / Leon Harding (confirmed)
* Patio Lunch (provided, 12 noon)
* Afternoon Sessions (1pm) -- E. Hamden, Session Chair
- Projects in development using EMCCDs (1-2p)
- FIREBALL / GEONIS / NGDBSP / VERVE - Erika Hamden & Gillian Kyne / Nick Konidaris / Kent Wallace
- Panel Discussion -- E. Hamden, Moderator (2-3p)
- Lab demonstrations needed and/or planned tests
- Technical issues: Dark Current / CIC / Low-T CTE / Lifecycle Issues
- EMCCD calibration unique concerns
* Coffee Break (3p)
- New applications / concept / science frontiers (3:20p)
- EMCCDs for Exoplanet Imaging / Adaptive Optics (Robo-AO) -- Rich Dekany
- EMCCDs as Telescope Guiders -- Jennifer Milburn
- EMCCDs for Wavefront Sensors -- Dimitri Mawet
- General Discussion (4p) -- Rich Dekany, Moderator
- Possible topics include:
- Influencing vendors, commercial development / Coordinating EMCCD eval. and testing (incl. environ.) / Sky vs. Space backgrounds / Coincidence loss problems / Outlandish new ideas
- Publishing more results from our real astronomy with EMCCDs
* Adjourn
* Happy Hour at Rath al Fresco
Links
- Add other external links here
Related Papers or References
Minutes
- Messages to vendors
- A lower noise output amplifier would help astronomers not have to run at as high a gain before entering the photon-counting regime.
- Why are the current choices among commercial options so crumby?
- Importance to this community to prove EM operation with deep-depletion (DD) CCDs?
- First Light (France) is an alternative commercial EMCCD camera vendor; OCAM2K camera being used in SPHERE for wavefront sensing.
- Other vendors for EMCCDs themselves?
- Panel Discussion Notes
- Panel: S. Nikzad, L. Harding, R. Jensen-Clem, N. Konidaris, T. Goodsall, E. Hamden (Moderator)
- Q1: What kinds of tests of EMCCDs are your groups performing?
- EH/FIREBALL: concentrating on dark current measurements right now
- SN: improving QE, particularly at short wavelengths + dark current, uniformity, and stability of performance; includes UV spectrometer studies
- LH: testing for radiation damage, including impact on CIC, CTE, and dark current
- C. Martin: this community would benefit from development of the optimal design independent of any one specific mission; how could we integrate efforts?
- RJ-C: investigating photon arrival statistics for exoplanet search/study; issue: how are we sure that zero signal corresponds really to zero photons?
- TG: starting to look into accurate measurement of quantum yield for UV applications (more than one e- per input photon).
- Q2: What have peer reviewers said in response to recent flight proposals?
- SN: reviewers want to see test data from actual assets you plan to fly (exact format, etc.); more evidence of successful out-of-band rejection; sounding rocket demonstrations sometimes criticized for not following exact science objectives as flight mission.
- R. Smith: would cubesat or ISS demonstrations help prove readiness; SN: yes, but care should be taken to demonstrate the right device, based on mission planning.
- NK: as reviewer and reviewee, some researchers see to take EMCCD performance for granted; need to honestly represent understanding of advantages and limitations
- RD: as we've heard today, for key applications the advantages are real and we should disseminate this better in the broader astronomy community.
Follow-on Action Items
- Dekany: Add First Light to commercial vendor slide - 8/18/15