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By inserting a MEMS deformable mirror-based adaptive optics system into the beam transfer optics of the Shane 3-meter telescope at Mt. Hamilton, we actively controlled the wavefront of the outgoing sodium laser guidestar beam. It was possible to show that a purposefully aberrated beam resulted in poorer performance of the Adaptive Optics system located behind the primary, though bad seeing conditions prevented us from improving the system’s performance over its nominal state. A silver-coated Iris AO deformable mirror was subjected to approximately 9.5 hours of exposure to a sodium laser guidestar of 3.5 Watts average output power and showed no signs of permanent damage or degradation in performance. Future applications of the uplink-AO system for correcting atmospheric turbulence and in generating custom laser guidestar asterisms are also discussed.

The Lick Observatory 3-meter telescope has a history of serving as a testbed for innovative adaptive optics techniques. In 1996, it became one of the first astronomical observatories to employ laser guide star (LGS) adaptive optics as a facility instrument available to the astronomy community. Work on a second-generation LGS adaptive optics system, ShaneAO, is well underway, with plans to deploy on telescope in 2013. In this paper we discuss key design features and implementation plans for the ShaneAO adaptive optics system. Once again, the Shane 3-m will host a number of new techniques and technologies vital to the development of future adaptive optics systems on larger telescopes. Included is a woofer-tweeter based wavefront correction system incorporating a voice-coil actuated, low spatial and temporal bandwidth, high stroke deformable mirror in conjunction with a high order, high bandwidth MEMs deformable mirror. The existing dye laser, in operation since 1996, will be replaced with a fiber laser recently developed at Lawrence Livermore National Laboratories. The system will also incorporate a high-sensitivity, high bandwidth wavefront sensor camera. Enhanced IR performance will be achieved by replacing the existing PICNIC infrared array with an Hawaii 2RG. The updated ShaneAO system will provide opportunities to test predictive control algorithms for adaptive optics. Capabilities for astronomical spectroscopy, polarimetry, and visible-light adaptive optical astronomy will be supported.

The University of California (UC) began operating the Lick Observatory onMount Hamilton, California in 1888. Nearly a century later, UC became a founding partner in the establishment of theW. M. Keck Observatory (WMKO) in Hawaii, and it is now a founding partner in the Thirty Meter Telescope (TMT) project. Currently, most UC-affiliated observers conduct the majority of their ground-based observations using either the Keck 10-meter Telescopes on Mauna Kea or one or more of the six Lick telescopes now in operation on Mount Hamilton; some use both the Keck and Lick Telescopes. Within the next decade, these observers should also have the option of observing with the TMT if construction proceeds on schedule. During the current decade, a growing fraction of the observations on both the Keck and Lick Telescopes have been conducted from remote observing facilities located at the observer's home institution; we anticipate that TMT observers will expect the same. Such facilities are now operational at 8 of the 10 campuses of UC and at the UC-operated Lawrence Berkeley National Laboratory (LBNL); similar facilities are also operational at several other Keck-affiliated institutions. All of the UC-operated remote observing facilities are currently dual-use, supporting remote observations with either the Keck or Lick Telescopes. We report on our first three years of operating such dual-use facilities and describe the similarities and differences between the Keck and Lick remote observing procedures. We also examine scheduling issues and explore the possibility of extending these facilities to support TMT observations.

The Lick Observatory is pursuing new technologies for adaptive optics that will enable feasible low cost laser guidestar systems for visible wavelength astronomy. The Villages system, commissioned at the 40 inch Nickel Telescope this past Fall, serves as an on-sky testbed for new deformable mirror technology (high-actuator count MEMS devices), open-loop wavefront sensing and control, pyramid wavefront sensing, and laser uplink correction. We describe the goals of our experiments and present the early on-sky results of AO closed-loop and open-loop operation. We will also report on our plans for on-sky tests of the direct-phase measuring pyramid-lenslet wavefront sensor and plans for installing a laser guidestar system.

The wavefront sensor camera and tip/tilt sensor APDs that were on Lick Observatory's Shane 3 Meter Adaptive Optics system were over a decade old and showing their age. They were recently upgraded. The first upgrade was to convert from quad-APDs in the laser guidestar mode natural star tip-tilt sensor to a sensitive low-noise CCD. The new CCD in this position, an 80x80 E2V CCD-39 inside a SciMeasure camera, has a low enough read noise, ~3 e-/pixel, that the tip/tilt measurement in closed-loop operation is photon noise limited and thus benefits from the improved quantum efficiency of the CCD. We have demonstrated on-sky up to two magnitudes of improvement in viable tip/tilt star brightness, which greatly extends the available sky coverage in the laser guidestar AO mode. Also, the increased field of view of the new tip/tilt sensor provides a much more reliable means of acquiring and locking on dim tip/tilt stars, making the whole system operationally more efficient. In the second phase of the upgrade project, the high order wavefront sensor has been replaced, also with a CCD-39 chip in a SciMeasure camera. In this paper we will describe these upgrades and present preliminary performance results.

Measurements of anisoplanatism from data obtained with natural guide star adaptive optics on the Lick Observatory 3m are presented. These were obtained from short exposures of binary stars with the IRCAL camera whose field of view (~20”) is generally considered isoplanatic in the K-band. However, measurable amounts of high-order anisoplanatism were present at separations of ~7” and ~12” with an isoplanatic patch size estimated to be ~26”. Within this field, there was measureable differential image motion between the binary star components. This image motion was small compared to the size of the diffraction-spot and therefore had negligible effect.

The Lick Observatory laser guide star adaptive optics system has undergone continual improvement and testing as it is being integrated as a facility science instrument on the Shane 3 meter telescope. Both Natural Guide Star (NGS) and Laser Guide Star (LGS) modes are now used in science observing programs. We report on system performance results as derived from data taken on both science and engineering nights and also describe the newly developed on-line techniques for seeing and system performance characterization. We also describe the future enhancements to the Lick system that will enable additional science goals such as long-exposure spectroscopy.

Results of experiments with the laser guide star adaptive optics system on the 3-meter Shane telescope at Lick Observatory have demonstrated a factor of 4 performance improvement over previous results. Stellar images recorded at a wavelength of 2 micrometers were corrected to over 40 percent of the theoretical diffraction-limited peak intensity. For the previous two years, this sodium-layer laser guide star system has corrected stellar images at this wavelength to approximately 10 percent of the theoretical peak intensity limit. After a campaign to improve the beam quality of the laser system, and to improve calibration accuracy and stability of the adaptive optics system using new techniques for phase retrieval and phase-shifting diffraction interferometry, the system performance has been substantially increased. The next step will be to use the Lick system for astronomical science observations, and to demonstrate this level of performance with the new system being installed on the 10-meter Keck II telescope.

We present the preliminary results of a laboratory experiment using phase diversity as a wavefront sensor. Computer simulations of this experiment were also performed. The phase diversity algorithm used the ordinary finite-difference method to solve the transport equation of intensity and phase. This method of phase diversity retrieves the phase directly and may prove to be useful for low light level applications and for extended objects. This entertains the possibility of using phase diversity as an on-line wavefront sensor for adaptive optics.