1 / 30

WFC3 Ambient Calibration #2 Results H. Bushouse

WFC3 Ambient Calibration #2 Results H. Bushouse. Ambient Cal #2 Overview. WFC3 ambient calibration #2 ran from April 13-19, 2007 WFC3 in the GSFC SSDIF clean room Latched into Radial Instrument Alignment Fixture (RIAF) and “CASTLE” optical stimulus

salome
Download Presentation

WFC3 Ambient Calibration #2 Results H. Bushouse

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. WFC3 Ambient Calibration #2 Results H. Bushouse

  2. Ambient Cal #2 Overview • WFC3 ambient calibration #2 ran from April 13-19, 2007 • WFC3 in the GSFC SSDIF clean room • Latched into Radial Instrument Alignment Fixture (RIAF) and “CASTLE” optical stimulus • UVIS channel operations only (IR can’t be cooled sufficiently in ambient) • UVIS-2 detector with CCD’s at -54 C (vs. -83 C flight temp) • Goals: • Verify re-integrated instrument operations • Verify successful lien closures • First look at UVIS-2 in (nearly) flight-like conditions • Verify operations of ground support equipment to be used in thermal-vac #2 • Train and verify operations of support personnel

  3. Instrument Preparations forAmbient Cal #2 WFC3 closeout just prior to top cover installation WFC3 top cover installed WFC3 inserted into Radial Instrument Alignment Fixture (RIAF) WFC3 lift from Low Level Positioner (LLP)

  4. Accomplishments • ~30 SMSs, ~110 hours, 1525 images • Optical stimulus verification • UVIS-2 detector alignment check • System throughput with UVIS-2 • Filter ghost check (lien related) • CCD electronic crosstalk check (lien related) • UVIS grism calibration: throughput, dispersion, and flat fields • Internal Calibration Subsystem check (lien related) • UVIS-2 bias, dark, readnoise, gain measurements • UV flats signal level check • Encircled energy check • CCD charge injection test • First test of CCD Extended Pixel Edge Response (EPER) mode • Excellent job by I&T, Ops, CASTLE & Sci Cal teams

  5. Thanks are due … • IS’s • S. Baggett, T. Brown, H. Bushouse, G. Hartig, A. Martel, L. Petro, M. Robberto • DA’s • E. Barker, M. Cracraft, B. Hilbert, S. Holfeltz, D. Karakla, J. Kim, K. Lindsay, D. Long, R. Lucas, J. Mack, H. McLaughlin, C. Pavlovsky, B. Shaw, E. Smith, M. Sosey

  6. Instrument Science Reports • ISR 2007-15: WFC3 Ambient-2 Testing: UVIS Readnoise S. Baggett 11 May 2007 • ISR 2007-14: WFC3 Ambient-2 Testing: Calibration Subsystem Performance S. Baggett 7 May 2007 • ISR 2007-13: UVIS CCD EPER CTE measurements M. Robberto 30 Apr 2007 • ISR 2007-11: WFC3 Ambient-2 Testing: UVIS Gain Results S. Baggett 27 Apr 2007 • ISR 2007-10: WFC3 Ambient Testing: UVIS Dark Current Rate B. Hilbert 26 Apr 2007 • ISR 2007-09: UVIS Channel Filter Ghosts after Filter Replacement T. Brown 26 Apr 2007 • ISR 2007-08: Searching for Scattered Light on the WFC3 UVIS-2 Detector T. Brown 24 Apr 2007 • ISR 2007-07: WFC3 System Throughput on the UVIS Build 2 Detector T. Brown 19 Apr 2007

  7. System Throughput with UVIS-2 From STScI Instrument Science Report WFC3-2007-07 (Tom Brown) • UVIS-2 QE better than predicted • Response of both CCDs comparable to UVIS-1 chip 1 • UVIS-2 curves subject to small revision at proper operating temp • Optics throughput appears to have held up well since 2004 TV#1

  8. UVIS Detector Throughput Comparison • UVIS-1 wins in blue; UVIS-2 wins in red • F225W only important filter for which response differs by >10%

  9. Excellent Read Noise w/ UVIS-2 • Like UVIS-1, UVIS-2 demonstrates “goal” level read noise of 3 e- rms, vs. spec of 4; very important in UV S. Baggett

  10. UVIS Crosstalk Satisfactorily Resolved • Extended source crosstalk (which could result from very low level signals) is now undetectable (<0.1 e-) • Combination of hardware change and timing pattern change • New timing patterns show slightly improved read noise as well (had been concerned they might have higher noise) • No crosstalk in 2-amp readouts (i.e. from CCD to CCD) • In 4-amp readout, small level of crosstalk remains from saturated sources only • New timing patterns slightly improve that level as well • What remains is not a significant issue preliminary analysis by S. Baggett

  11. UVIS Crosstalk Satisfactorily Resolved (2) Performance w/Hardware Rev & New CCD Timing Patterns Original Problem window-CCD ghost filter-CCD ghost crosstalk source stimulus artifacts

  12. Internal Cal Subsystem Illumination Improved • Severe glints reduced; see F390M flats below • Count rate specs achieved • As shown previously w/UVIS-1, Deuterium flats much improved in uniformity (2× vs. 5-10×) F390M (inverse) flat before F390M flat now

  13. UVIS Grism Throughput Measured UVIS grism is WF/PC-1 spare; very little surviving data Data provided to SOC for ERS planning H. Bushouse

  14. CCD Charge Injection Working Properly Mean charge injection signal level ~16,000 e-/pix Noise in a single column ~15 e- rms Much greater CTE benefit than from a lamp pre-flash of equivalent noise level

  15. Improved Filter Ghost Performance Confirmed • Ambient cal measurements confirm the improved ghost performance of the filters replaced in the SOFA • Biggest success stories: F225W (<0.4% vs. 15%), F606W (elimination of point-like ghosts), F280N (0.6% vs. 10-50% in ghost and horrific scattered light flares) Old F225W New F225W

  16. UVIS-2 Detector Alignment • UVIS-2 aligned at Ball on 30 Jan ’07 • used new, direct, “through the window” alignment transfer from UVIS-1 to UVIS-2 • UVIS-2 within tolerance in 4 degrees of freedom, out in 2 • Additional adjustment of tip/tilt is desirable, if misalignment is confirmed in upcoming TV#2 testing

  17. UVIS-2 Misalignment Consequences • At best focus, the performance degradation due to the current level of tip/tilt misalignment is negligible, however … • OTA breathing exacerbates the misalignment, causing a small loss of performance over field, especially at short wavelengths • Slight EE loss in small apertures • PSF change (due to field dependent astigmatism inherent in optical design)

  18. What’s Next? • IR-1 detector package installation • Received at GSFC yesterday (5/16); installation today • System Level Thermal-Vac #2 • WFC3, with UVIS-2 and IR-1, into SES chamber ~5/29 • Ambient system functionals and alignment check ~6/1-6/5 • Vacuum testing for following ~75 days • 24/7 support from STScI IS’s, DA’s, and Ops • Proto-flight qualification of instrument • Thermal cycling • Performance of all thermal systems • Full science calibration of UVIS and IR channels • CEI specifications verification

  19. IR FPA QEs

  20. Backup slides

  21. UVIS-2 Misalignment EE Penalty OTA SM despace: +3m Nom -3m Detector alignment: Optimal As-is Optimal As-is

  22. PSF Change with OTA Breathing UVIS-2 CASTLE 633nm UV-11 0m +3m -3m

  23. FPA 160 Dark Current

  24. FPA 160 Persistence

  25. FPA 160 Read Noise

  26. FPA 165 QE

  27. SMGT preparations • Revised SMGT Part 2 SMS • Added UVIS Anneal exposures • Revised management of tungsten & D2 lamps • Corrected UVIS quad filter commanding • Duration of SMS is 20.5 hours • Delivered SMS 3/30/2007 for test • SMS ran successfully in VSTIF 4/23/2007 • Science data ftp’ed to STScI for OPUS processing • Revised SOGS Support Schedules for SM4 Functional Test • Science data from Early VEST test ftp’ed to STScI for OPUS processing • Prepared OPUS for processing of VSTIF and Early VEST data • Anomalies identified from February VSTIF run corrected • Software testing and delivery complete by 5/2/2007

  28. SMGT Part 2 SMS Content

  29. Preparation ofSMGT Part 2 SMS

  30. SMGT VSTIF Results

More Related