PALM-3000 Observers Information - 2013B

Overview

2013B Call for Proposals

• Detailed COO Call for Proposals

Instruments Status

• PALM-3000 has achieved first on-sky correction with both the low- and high-order DM's. Engineering tests indicate initial performance in the range of 150-160 nm RMS wavefront error (peak K-Strehl = 82% to date), not yet at the expected performance level of 105 nm RMS (the 105nm requirement is for a V = 5 guide star (in median seeing conditions), current performance of 160nm RMS has been seen down to V = 8).
• Instrument Status:
  • PHARO (public)
    • Is currently operational at the summit. A new entrance window was installed in October 2012, replacing the very dirty original window.
  • SWIFT (public)
    • Is performing routine science in both AO-fed and AO-passthrough (seeing-limited) operation.
  • P1640 (private, PI: B. Oppenheimer, AMNH)
    • Coronagraph + CAL is performing routine science.
  • Fiber Nuller (private; PI: G. Serabyn, JPL)
    • Initial FN tests with PALM-3000 successful in June 2012.
  • TMAS (private; co-I's: R. Dekany and S. Hildebrandt, COO)
    • First light successful 27 Sept 2012. Improved flat-fielding strategies under investigation.

Measured Performance vs. NGS Brightness

• s64 pupil sampling mode: Small (8.3cm) subapertures
  • We show below the P3K+PHARO K-band Strehl ratio obtained in June 2012, September 2012, and March 2013 taken in a variety of seeing conditions over 6 nights. The data clearly show the progression of instrument performance from 2011 to present, especially on bright guide stars. No consistent optimization of frame rate for each guide star was attempted for these data sets (we were doing other engineering and not specifically exploring the frame rate parameter space). We intend a more rigorous strehl investigation on bright to faint stars in May 2013.
• s32 pupil sampling mode: Larger (16.2 cm) subapertures
  • We have successfully commissioned the 32x pupil sampling mode during our engineering night on March 22, 2013. The Palomar staff can now operate P3K in both 64x and 32x pupil sampling modes.
  • Based on expected P3K performance and our experience on a few targets on March 22 (see figure below), we suggest using 64x mode on targets brighter than 12 mv if the visible seeing is at or better than 1.0". For target stars fainter than 9 mv in visible seeing greater than 1.0", 32x mode may perform better than 64x. The Palomar staff can help you determine which mode may be best given the local conditions.
  • 32x did out-perform 64x on 11.5 and 13 mv target stars on the night of March 22 in 15-20 mph surface winds and variable seeing conditions (1.0-1.7 Ksh seeing).
• s8 pupil sampling mode: Largest (65 cm) subapertures
  • Will NOT be available until 2014 at the earliest
• Performance optimizations are on-going through FY13.

Expected System Capabilities

PALM-3000 correction will be best in the direction of the guide star, and fall off due to atmospheric anisoplanatism. The corrected field of view diameter will vary with conditions, but is generally expected to be between 1-2 arcmin diameter in K-band, decreasing to 10-20 arcsec in I-band.

Guide Star Selection

PALM-3000 has a patrol range for NGS selection of ~90 arcsecond in diameter (allowing a guide star up to 90" away from the science target to be utilized, with the understanding that anisoplanatism error (not accounted for in any data elsewhere on this page) degrades performance significantly beyond ~30 arc sec radius in H/K bands (and beyond ~15 arc sec in Y/J bands.)

The WFS acquisition camera FOV is ~ 95 arc sec x 80 arc sec (TBC).

Ultimate Expected Performance on Bright Guide Stars

The bright star wavefront error budget for PALM-3000 is as follows:

* Assumptions

• Mean turbulence weighted wind speed = 9.5 m/s
• Zenith pointing
• Guide star brightness V ~ 5
• AO mode: s64

Expected Observing Overheads

Closed-loop AO image dithering on PHARO is expected to be functional at a level equal to or better than the prior PALMAO system (smallest step size ~ 5 mas), with improved non-common-path flexure during long exposures. Early engineering tests confirm PALM-3000 has improved flexure stability compared to PALMAO. These results are being quantified.

Wide-field astrometry

Extended objects

Contact information