Keck Laser Guide Star Adaptive Optics System 1

Keck Laser Guide Star Adaptive Optics System: 1 st & 2 nd Milestones AOWG Telecon Oct. 17, 2003 A. Bouchez, J. Chin, A. Contos, S. Hartman, E. Johansson, R. Lafon, D. Le Mignant, P. Stomski, D. Summers, M. van Dam, P. Wizinowich

Topics ¯ Review 1 st light results ¯ Preliminary definition of 2 nd light milestone & progress ¯ Other priorities

LGS AO Top-level Milestones ¯ Top-level milestones (as of fall/02): ü 03 Q 4 - 1 st corrected images on NIRC 2 with laser • ± ± ± Achieved Sept. 18 & 19, 2003 04 Q 1 – LGS AO facility operable by AO experts 04 Q 2 – 1 st engineering science 04 Q 3 – 1 st shared risk science 05 Q 2 – Operable for science by OA & 1 expert 05 Q 3 – 1 st queue scheduled science observing

First LGS Milestone Definition ¯ ü Definition of the first corrected LGS AO images on NIRC 2 (KAON 235). Success Criteria: Achieve a Strehl ratio > 0. 2 in Kp for the AO corrected image in the following situation: ü NIRC 2 image with an exposure time > 30 sec. ü Down tip/tilt loop closed on a NGS V > 13 mag. • ü • Higher order loop closed on the LGS. Average seeing conditions. • ü ü Excellent to extraordinary seeing. Telescope elevation > 60 & < 80. Science object < 5 arcsec from NGS star. NGS < 10 arcsec off the image rotator axis. • ü Achieved SR = 0. 25 in Kp on a V = 14 NGS. Both NGS and LGS on-axis for 1 st light. Rotator in vertical angle mode at optimal angle for laser. • Also demonstrated in position angle mode.

First LGS Results (UT 9/20) “Audentes Fortuna Juvat” Virgile Extraordinary seeing

HK T Tauri B (UT 9/20) The star shown at the bottom right is the 106 yr old classical T Tauri star HK Tau A. HK Tau B at top left is believed to lie in the dark lane of a circumstellar disk. • NGS Vmag = 15 • Strehl = 4% at H & 12% at K’. • FWHM = 0. 14, 0. 11 & 0. 13 mas at H, K’ & L’. • Exposure time = 30, 40 & 72 sec at H, K’ & L’. • Position angle = 145 • 240 counts from LGS on wavefront sensor at 500 Hz 3 color image: H, K’ & L’ are blue, green & red, respectively.

The LGS AO Team in Celebration

Acquisition Camera image of the LGS (UT 9/19 after optimization) LGS FWHM varied from 1. 4 to 1. 8 arcsec Altitude ~ 88 km Rayleigh scatter

Acquisition Camera image of the LGS with the primary mirror unstacked LGS best segment FWHM from 1. 4” when stacked image was 1. 7”

Significant Technical Progress (in support of this milestone) ¯ STRAP operational standalone as tip/tilt sensor ¯ LBWFS operating in 1 x 1 & 2 x 2 pixel binning ± ¯ ¯ Providing focus to WFS stage & centroids for optimization Wavefront sensor tracking versus elevation Image sharpening based on LBWFS centroids successful Laser image quality & power fairly stable Laser diagnostics operational ± LGS size qualitatively correlated with pointing & PIB images ¯ Laser pointing with M 3 ¯ Operation scheme & prelim automation successful ¯ Plus: ± ± ± Laser Traffic Control System operational EPICS upgrade for WFC command processor operational K 2 aoserver operational for idl & Java tools (from HQ)

LGS AO Control Light from Telescope Offload to telescope Tip/tilt TTM LGS NGS IR transmissive dichroic Offload focus to telescope Science Camera DM Wavefront Controller Sodium transmissive dichroic STRAP Lenslets WFS LBWFS (Tip/tilt to Laser) Focus TSS x, y, z stage Centroids (Subaperture gains) Pupil Orientation

Laser Diagnostics

Error Budget

2 nd LGS Milestone Definition Proposed Criteria • LGS facility operable by AO experts (by end of Dec/03). • Performance Success Criteria: 1. 2. 6. 9. • Operability Success Criteria: 3. 4. 5. 7. 8. • Achieve a Strehl > 0. 2 in Kp for a V > 15 mag NGS. Achieve a Strehl > 0. 1 in Kp for a V > 17 mag NGS. Corrected images on science camera < 5 min after slew. Nod time < 20 sec (including opening & closing loops). LGS AO operable by 3 AO + 1 laser expert (+ NIRC 2 operator). All software tested & released in a controlled version (by Dec. 15) Demonstrate correction over 50° < EL < 85°. Off-axis science demonstrated for a target > 20 arcsec from NGS. Nodding demonstrated over a 5 x 5” field. Numbers indicate relative priorities. • Faint performance higher priority than off-axis operation

2 nd LGS Milestone Tasks

2 nd LGS Milestone Tasks

2 nd Light Run Summary (Oct. 10&11) ¯ Cirrus/clouds for entire run. Managed to project laser through holes for short periods ± Inadequate time to demo good LGS AO correction ¯ Laser progress ± ± ± Ran from summit control room (no laser access reqd) Start of night alignment adequate for night Much progress on understanding laser pointing ¯ LGS AO progress ± ± ± Progress on punchlist items, especially focus correction Some training with tools No progress on STRAP limiting mag since background high again (had been reduced prior to run) ¯ Good NGS science performed through cirrus

Other AO FY 04 Milestones

NGS AO Tasks

K 2 AO Observing Calendar 1. 2. ¯ ¯ Sept. None after 9/18. Oct. 2 -5 NIRC 2; 10 -11 LGS; 12 -16 IF Nov. 8 -11 NIRC 2; 14 -16 IF; 17 LGS; 27 -30 NIRC 2 Dec. 5 -8 NIRC 2; 10 LGS; 11 -13 NIRSPAO; 15 -17 LGS; 16 -18, 23 -26, 29 -31 NIRC 2 ¯ Jan. 5 -8 IF; 5, 9 -12, 27 NIRC 2 ± Only ½ night on 1/27 ¯ Appropriate gaps for significant AO changes: ± ± ± 15 wk days from Fri. 10/17 to Th. 11/6. 6 wk days from Tue. 11/18 to Tues. 11/25. 9 wk days from Tue. 1/13 to Fri. 1/23. ¯ Larger gaps available for laser changes.

AO 03 B Calendar

AO 03 B Calendar

AO 03 B Calendar