The Gemini Observatory and University of Hawaii are planning to install an 85-element curvature adaptive optics system with a laser guide star system on its Cerro Pachon telescope in 2001. This paper discusses the motivation, issues on implementing a laser guide star with a curvature-based system, the implementation of a laser guide star based on a commercially available 2W ring-dye laser, and the expected performance of the system. Detailed simulations show very promising results for system performance down to natural guide star magnitudes of 19 - 20th magnitude. The performance cross- over point between NGS and LGS is between 13 - 16th magnitude depending on the performance parameter of interest (e.g. Strehl, energy through a slit, etc.).

The bright stellar content near the center of the Local Group elliptical galaxy M32 is investigated with 0".12 FWHM H and K images obtained with the Gemini Mauna Kea telescope. Stars with K = 15.5, which are likely evolving near the tip of the asymptotic giant branch (AGB), are resolved to within 2" of the nucleus, and it is concluded that the peak stellar brightness near the center of M32 is similar to that in the outer regions of the galaxy. Moreover, the projected density of bright AGB stars follows the visible light profile to within 2" of the nucleus, indicating that the brightest stars are well mixed throughout the galaxy. Thus, there is no evidence for an age gradient, and the radial variations in spectroscopic indices and ultraviolet colors that have been detected previously must be due to metallicity and/or some other parameter. We suggest that either the bright AGB stars formed as part of a highly uniform and coherent galaxy-wide episode of star formation or they originated in a separate system that merged with M32.

Atmospheric turbulence distorts the wavefront of the incoming light from an astronomical object and so limits the ability of a telescope to form a perfect image. The AO systems for astronomy had come the most powerful tool for infrared observation in the near thermal domain. A conventional AO system requires quite a few reflections that are needed to transfer and correct an image. A typical system would have a collimator, deformable mirror and a camera at the bare minimum. For the thermal region the gains are substantial where one can eliminate extra optical surfaces and their associated thermal background, that occurs when you put the deformable mirror at the secondary. We study the possibility of development an adaptive secondary with the techniques of a Current Bimorph mirror with the necessaries number of actuators for control the edge slope. Also we simulate the performance of a 19 channels curvature adaptive optics system in order to demonstrate the gain achievable with an adaptive secondary. The adaptive secondary for the 2.1 m Telescope at SPM Observatory is designed for a f/50 beam, 100 mm in diameter with 19 actuators necessaries to control the edge slope and curvature.

The IRTF is a 3.0 meter, f/38, infrared optimized, cassegrain telescope operated under contract from NASA with the primary mission of providing ground-based support for NASA's planetary missions. We are currently in the design and construction phase of a 36 element, curvature-based, natural guide star, adaptive optics facility installation for the IRTF. System architecture will be modeled on the highly successful AO systems developed at the University of Hawaii. The system should achieve an AO efficiency, q >= 0.4. The Strehl ratio is expected to exceed 0.8 in the K band. We estimate a limiting guide star magnitude for full correction of mR equals 14.4.

All existing night-time astronomical telescopes, regardless of aperture, are blind to an important part of the universe - the region around bright objects. Technology now exist to build an unobscured 6.5 m aperture telescope which will attain coronagraphic sensitivity heretofore unachieved. A working group hosted by the University of Hawaii Institute for Astronomy has developed plans for a New Planetary Telescope which will permit astronomical observations which have never before ben possible. In its narrow-field mode the off-axis optical design, combined with adaptive optics, provides superb coronagraphic capabilities, and a very low thermal IR background. These make it ideal for studies of extra-solar planets and circumstellar discs, as well as for general IR astronomy. In its wide-field mode the NPT provides a 2 degree diameter field for surveys of Kuiper Belt Objects and Near-Earth Objects, surveys central to current intellectual interests in solar system astronomy.

The University of Hawaii adaptive optics program has recently moved its 36 actuators system, named "Hokupa'a 36", to the Gemini North Telescope. First light for Hokupa'a 36 was in time for the dedication of this telescope during June 1999 and most of the images presented were taken with this adaptive optics system. This paper will cover the modifications to the CFHT, Hokupa'a 36 system that were necessary to accommodate the larger 8 meter aperture of the Gemini Telescope. Performance at the telescope has now been measured and compares favorably with that predicted.

We have obtained high-resolution (FWHM = 0." 15) deep images of the UY Aur binary at J, H, and K' with the University of Hawaii adaptive optics instrument. We clearly detect an R similar to 500 AU circumbinary disk discovered with millimeter interferometry, making UY Aur the second young binary with a confirmed circumbinary disk. It appears that the disk is inclined similar to 42 degrees from face on. We find that the near side of the disk is brighter than the far side by factors of 2.6, 2.7, and 6.5 times at K', H, and J, respectively. The original CG Tau circumbinary disk has been reexamined and is found to have similar flux ratios of 1.5, 2.6, and 3.6 at K', H, and J, respectively. A realistic power-law distribution (p = 4.7) of spherical dust aggregates (composed of silicates, amorphous carbon, and graphite) that reproduces the observed ISM extinction curve also predicts these observed flux ratios from Mie scattering theory. We find the observed preference of forward-scattering over back-scattering is well fitted (global chi(2) minimization) by Mie scattering off particles in the range a(min) = 0.03 mu m to a(max) = 0.5-0.6 mu m. The existence of a significant population of grain radii larger than 0.6 mu m is not supported by the scattering observations.Based on the observed disk inclination we derive an orbit for UY Aur where the mass for the binary is 1.6(-0.67)(+0.47) M.. Based on the observed K7 and M0 spectral types for UY Aur A and B, accretion disk models for the inner disks around the central stars were constructed. The models suggest that small (lower limit R similar to 5-10 AU) inner disks exist around B and A. It appears that B is accreting similar to 5 times faster than A, and that both inner disks may be exhausted in similar to 10(2)-10(3) yr without replenishment from the outer circumbinary disk. Our images suggest that these inner disks may indeed be resupplied with material through thin streamers of material that penetrate inside the circumbinary disk. Currently it appears that such a streamer may be a close to UY Aur B. Comparison of our IR images and the millimeter images of the gas clearly show that the dust seen in our IR images traces the gas in the circumbinary disk, as was also the case with GG Tau.

The University of Hawaii AO group has been actively carrying out astronomical AO observations for the last four years. The UHAO group and out collaborators have utilized the curvature AO system to obtain diffraction-limited images of asteroids, planets, moons, protoplanetary disks, young stars, young star clusters, planetary nebulae, black holes, galaxies and quasars. The current scientific capabilities of the new 36-actuator Hokupa'a AO curvature system will be briefly reviewed. Four key astronomical situations that are excellent for AO observations will be discussed. Examples of scientific observational techniques will be highlighted with actual AO astronomical results.

The University of Hawaii adaptive optics program has scaled its previously successful 13 elements AO system to 36 actuators and named it 'Hokupa'a', meaning 'immovable star' in Hawaiian. First light for Hokupa'a in early November of 1997, was on the Canada France Hawaii Telescope on Mauna Kea, an f/35, 3.35 meter telescope. Performance at the telescope has now been measured and compares favorably with that predicted theoretically. The extension to 36 elements has now allowed the system to give diffraction limited performance down to I band on stars as faint as 12.5 magnitude in median 0.7 arcsecond seeing on Mauna Kea. Like our previous system, extensive computer simulations were carried out to achieve the best possible match between the curvature WFS and the deformable curvature mirror.

We present high-resolution (FWHM = 0''.2) near-IR (J, H, and K') adaptive optics images of the Herbig Ae/Be star R Monocerotis. Optical Hubble Space Telescope (HST) WFPC2 PC camera archival images are also presented. For the first time, adaptive optics was utilized to make high-resolution (FWHM = 0''.2) IR-imaging polarimetry maps of R Mon. In addition, the first mld-IR array images (at 11.7 and 20.8 mu m) of R Mon have been obtained. We also present new 3.16, 3.93, and 4.67 mu m images.We have found that R Mon is a 0''.69 binary star with a companion that dereddens onto the classical T Tauri locus. Based on the near-infrared photometry of this companion we believe it is a 1,5 M., very young (< 3 x 10(5) yr) classical T Tauri star. The close presence of a young companion suggests that R Mon itself is a rare example of a very young isolated massive star.At the highest resolutions, R Mon is revealed to be extended by similar to 0''.1 east-west, and similar to 0''.05 north-south in the visible. The young R Mon star is not directly visible in the optical but appears as a resolved conical reflection nebula in scattered light. At infrared wavelengths, the dense circumstellar dust is penetrated and R Mon appears to be an unresolved point source located at 0''.06 +/- 0''.02 south of the peak optical flux.The large-scale optical-IR morphology of R Mon and its large reflection nebula (NGC 2261) suggests a thin bipolar parabolic shell of dust. The appearance of the parabolic shell is consistent with an inclination of 20 degrees +/- 10 degrees from the plane of the sky. This inclination implies that R Mon is located 760(-280)(+800) pc distant based on previous proper-motion and radial velocity measurements of R Mon's jet. Our high-resolution (FWHM similar to 0''.2) adaptive optics infrared polarimetry maps agree with the current interpretation that NGC 2261 is a reflection nebula illuminated by R Mon.Interior to the parabolic shell there is a complex of twisted filaments along the eastern edge. These filaments resemble a double-helical structure which is well described by a power law from similar to 10(3) to 10(5) AU from R Mon. This double helix may trace a twisted magnetic field above R Mon.Based on H I emission-line ratios, we find the direct extinction toward R Mon to be A(V) = 13.1 mag in the infrared (lambda > 1.28 mu m), falling to a lower value of A(V) = 3.6 mag in the optical (lambda < 1.28 mu m), where scattered light increasingly lowers the effective extinction in the line ratios. The large A, = 13.1 extinction is likely due to the dusty atmosphere of an inclined R similar to 100 AU optically thick accretion disk: surrounding R Mon. A simple model of such an accretion disk + star system (with M-acc similar to 8 x 10(-5) M., yr(-1), M-* 10.4 M-., R-* = 2 R., and T-* similar to 3.5 x 10(4) K) reproduces the observed dereddened R Mon spectral energy distribution (SED) from the optical (0.4 mu m) to the millimeter region. Consideration of the lower extinction (A(V) = 3.6) on the path followed by the scattered visible light eliminated ani need for an inner ''gap'' in the accretion disk model to reproduce the SED.In general, young stellar objects (YSOs) that are obscured in the optical but directly visible in the infrared will have different effective optical and infrared extinctions. Infrared extinctions derived from optical observations dominated by scattered Light will be underestimates of the true IR extinction along the direct path. The use of an independent estimator of both the optical and infrared extinctions such as common upper-level H I recombination lines is highly desirable. The utilization of the correct optical and infrared extinctions may relieve the need for optically thin inner-disk gaps to explain YSO near-IR SEDs.

We report on the results of the system simulation software written at Canada-France-Hawaii Telescope, to predict and optimize the performance of our adaptive optics bonnette presently under construction. The individual simulation elements, atmospheric simulator, curvature sensor, bimorph mirror and control loop, are reviewed with an emphasis on the basic properties of curvature sensors. Optimization of the extra-focal distance parameter and its consequences are discussed. We then present results of whole system simulations, and quantify the main sources of error. Some results, including noise, are reported. In a second part, we present our view of modal control and detail the construction of the modal basis. We also report briefly on modal gain optimization.

It is shown that low-order wavefront compensation can significantly improve astronomical images over most of the sky. A novel approach to wavefront sensing and compensation is described. It is optimized for low-order correction and high efficiency. Computer-simulation results show it can achieve the desired performance, and preliminary laboratory tests demonstrate its feasibility.