AO188/LGS status

1
AO188/LGS status

• AO188 development group(Subaru Telescope, NAOJ)
• 2009.1.16 (JST)

2
Outline

• Current status
• Risk shared open use
• Commissioning schedule

3
Current stats on SR.
9.1 mag
Sky background Oct 2008
15.7 mag
Aug 2008 Sep 2008 Oct 2008 Simulation
0.4_at_0.5mm Simulation 0.7_at_0.5mm
16.6 mag
4
Current status

• AO performance using natural guide stars (NGS)
• Observed SR matched with simulation results at
  faint end.
• Mismatch at bright end needs to be investigated.
• Need more statistics at various seeing condition.
• Detail analysis to compare the performance
  between simulation and observation is required.
• Improvement on performance is planning.

5
Current status

• Risk shared open use for AO188 with NGS
• Imaging/Spectroscopy/Grism modes of IRCS are
  available.
• AO acquisition time is about 10 to 15 minutes.
• AO parameter tuning takes about 5 minutes.
• 9-points dithering
• On slit dithering
• Field rotation correction and PA selection by AO
  image rotator.

6
Current status

• Engineering items.
• Non sidereal object. (Jan 15, 16)
• Field distortion. (Analysis is on going)
• Laser projection. (Jan 15, 16)
• F-conversion optics for IRCS. (on going)
• Isoplanatic angle. (Analysis is going on)
• Extended guide star performance. (on going)
• And so on

7
Upcoming work

• Performance improvement.
• Laser guide star (LGS) mode.
• LGS upgrade at wavefront sensor.
• Tip-tilt and focus guide star acquisition unit.
• Tip-tilt and focus wavefront sensor.
• Additional components.
• ADC.
• BS exchange system. (NGS mode lt-gt LGS mode)

8
Schedule and milestone

• Laser projection resumed on Jan 15.
• 9.5 engineering nights from Jan. to July.
• S09A open use of NGS mode. (10 nights)
• Some observing modes have a risk.
• Fabrication, test and install for new components
  start around April, 2009.

9
Schedule and milestone

• S09B open use of NGS mode.
• Fully functional.
• Engineering observation of LGS mode starts around
  autumn of 2009.
• Risk shared open use of LGS mode from S10A.

10
Summary

• Strehl Ratio at bright end is lower than that of
  simulation result.
• Mostly operational in NGS mode.
• Start testing on LGS mode this autumn.
• Risk-shared open use of LGS mode will start from
  S10A.