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in creator/contributor: "Olivier, S S"  
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Issues in the design and optimization of adaptive optics and laser guide stars for the Keck Telescopes

Description: We discuss issues in optimizing the design of adaptive optics and laser guide star systems for the Keck Telescope. The initial tip-tilt system will use Keck`s chopping secondary mirror. We describe design constraints, choice of detector, and expected performance of this tip-tilt system as well as its sky coverage. The adaptive optics system is being optimized for wavelengths of I-2.2{mu}m. We are studying adaptive optics concepts which use a wavefront sensor with varying numbers of subapertures… more
Date: March 1, 1994
Creator: Max, C. E.; Gavel, D. T. & Olivier, S. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Tip-tilt compensation: Resolution limits for ground-based telescopes using laser guide star adaptive optics. Revision 2

Description: The angular resolution of long-exposure images from ground-based telescopes equipped with laser guide star adaptive optics systems is fundamentally limited by the the accuracy with which the tip-tilt aberrations introduced by the atmosphere can be corrected. Assuming that a natural star is used as the tilt reference, the residual error due to tilt anisoplanatism can significantly degrade the long-exposure resolution even if the tilt reference star is separated from the object being imaged by a … more
Date: October 8, 1992
Creator: Olivier, S. S.; Max, C. E.; Gavel, D. T. & Brase, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simulation and analysis of laser guide star adaptive optics systems for the eight to ten meter class telescopes

Description: This paper discusses the design and analysis of laser-guided adaptive optic systems for the large, 8--10 meter class telescopes. We describe a technique for calculating the expected modulation transfer function and the point spread function for a closed loop adaptive optics system, parameterized by the degree of correction and the seeing conditions. The results agree closely with simulations and experimental data, and validate well known scaling law models even at low order correction. Scaling … more
Date: March 1, 1994
Creator: Gavel, D. T. & Olivier, S. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance of adaptive optics at Lick Observatory

Description: A prototype adaptive optics system has been developed at Lawrence Livermore National Laboratory (LLNL) for use at Lick Observatory. This system is based on an ITEX 69-actuator continuous-surface deformable mirror, a Kodak fast-framing intensified CCD camera, and a Mercury VME board containing four Intel i860 processors. The system has been tested using natural reference stars on the 40-inch Nickel telescope at Lick Observatory yielding up to a factor of 10 increase in image peak intensity and a… more
Date: March 1, 1994
Creator: Olivier, S. S.; An, J. & Avicola, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High-resolution wavefront control using liquid crystal spatial light modulators

Description: Liquid crystal spatial light modulator technology appropriate for high-resolution wavefront control has recently become commercially available. Some of these devices have several hundred thousand controllable degrees of freedom, more than two orders of magnitude greater than the largest conventional deformable mirror. We will present results of experiments to characterize the optical properties of these devices and to utilize them to correct aberrations in an optical system. We will also presen… more
Date: July 20, 1999
Creator: Bauman, B. J.; Brase, J. M.; Brown, C. G.; Cooke, J. B.; Kartz, M. W.; Olivier, S. S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance of laser guide star adaptive optics at Lick Observatory

Description: A sodium-layer laser guide star adaptive optics system has been developed at Lawrence Livermore National Laboratory (LLNL) for use on the 3-meter Shane telescope at Lick Observatory. The system is based on a 127-actuator continuous-surface deformable mirror, a Hartmann wavefront sensor equipped with a fast-framing low-noise CCD camera, and a pulsed solid-state-pumped dye laser tuned to the atomic sodium resonance line at 589 nm. The adaptive optics system has been tested on the Shane telescope … more
Date: July 19, 1995
Creator: Olivier, S. S.; An, J. & Avicola, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Improved performance of the laser guide star adaptive optics system at Lick Observatory

Description: 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 {micro}m were corrected to over 40% 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 {approx}10% of the theoretical peak inte… more
Date: July 20, 1999
Creator: An, J. R.; Avicola, K.; Bauman, B. J.; Brase, J. M.; Campbell, E. W.; Carrano, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser guide star adaptive optics: Present and future

Description: Feasibility demonstrations using one to two meter telescopes have confirmed the utility of laser beacons as wavefront references for adaptive optics systems. Laser beacon architectures suitable for the new generation of eight and ten meter telescopes are presently under study. This paper reviews the concept of laser guide star adaptive optics and the progress that has been made by groups around the world implementing such systems. A description of the laser guide star program at LLNL and some e… more
Date: March 1, 1993
Creator: Olivier, S. S. & Max, C. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phase retrieval for adaptive optics system calibration

Description: Our objective in this report is to develop methods to determine the output pupil wavefront using intensity measurements directly from the science detector. This wavefront can then be used to determine a reference wavefront which will precorrect for the non-common-path aberrations and produce the desired wavefront at the science detector. We describe two phase retrieval algorithms that can be used and a set of simulation studies of AO system calibration. We present the initial experimental resul… more
Date: August 1, 1997
Creator: Brase, J. M.; Carrano, C. J.; Macintosh, B. A.; Olivier, S. S. & An, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

First significant image improvement from a sodium-layer laser guide star adaptive optics system at Lick Observatory

Description: Atmospheric turbulence severely limits the resolution of ground-based telescopes. Adaptive optics can correct for the aberrations caused by the atmosphere, but requires a bright wavefront reference source in close angular proximity to the object being imaged. Since natural reference stars of the necessary brightness are relatively rare, methods of generating artificial reference beacons have been under active investigation for more than a decade. In this paper, we report the first significant i… more
Date: July 14, 1997
Creator: Olivier, S. S.; Max, C. E.; Friedman, H. W.; An, J.; Avicola, K.; Beeman, B. V. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Observing techniques for astronomical laser guide star adaptive optics

Description: We discuss astronomical observing requirements and their implementation using sodium-layer laser guide star adaptive optics. Specific issues requiring implementation include the ability to place the astronomical object at different locations within the field of view; reliable subtraction of Rayleigh-scattered light; efficient focusing; and stable point-spread-function characterization.
Date: May 1, 1998
Creator: Max, C. E.; Macintosh, B.; Olivier, S. S.; Gavel, D. T. & Friedman, H. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Direct imaging of extra-solar planets

Description: Direct imaging of extra-solar planets may be possible with the new generation of large ground-based telescopes equipped with state- of- the-art adaptive optics (AO) systems to compensate for the blurring effect of the Earth`s atmosphere. The first of these systems is scheduled to begin operation in 1998 on the 10 in Keck II telescope. In this paper, general formulas for high-contrast imaging with AO systems are presented and used to calculate the sensitivity of the Keck AO system. The results o… more
Date: March 1, 1997
Creator: Olivier, S. S.; Max, V. E.; Brase, J. M.; Caffano, C. J.; Gavel, D. T. & Macintosh, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Initial results from the Lick Observatory Laser Guide Star Adaptive Optics System

Description: A prototype adaptive optics system has been installed and tested on the 3 m Shane telescope at Lick Observatory. The adaptive optics system performance, using bright natural guide stars, is consistent with expectations based on theory. A sodium-layer laser guide star system has also been installed and tested on the Shane telescope. Operating at 15 W, the laser system produces a 9th magnitude guide star with seeing-limited size at 589 nm. Using the laser guide star, the adaptive optics system ha… more
Date: November 8, 1995
Creator: Olivier, S. S.; An, J. & Avicola, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Performance predictions for the Keck telescope adaptive optics system

Description: The second Keck ten meter telescope (Keck-11) is slated to have an infrared-optimized adaptive optics system in the 1997--1998 time frame. This system will provide diffraction-limited images in the 1--3 micron region and the ability to use a diffraction-limited spectroscopy slit. The AO system is currently in the preliminary design phase and considerable analysis has been performed in order to predict its performance under various seeing conditions. In particular we have investigated the point-… more
Date: August 7, 1995
Creator: Gavel, D. T. & Olivier, S. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High-accuracy calibration of an adaptive optics system using a phase shifting diffraction interferometer

Description: A phase-shifting diffraction interferometer (PSDI) has been integrated into an adaptive optics (AO) system developed by LLNL for use on the three meter Shane telescope at Lick Observatory. The interferometer is an all fiber optic design, which is extremely compact. It is useful for calibrating the control sensors, measuring the aberrations of the entire AO optical train, and measuring the influence functions of the individual actuators on the deformable mirror. The PSDI is particularly well sui… more
Date: June 23, 1999
Creator: Bauman, B. J.; Campbell, E. W.; Olivier, S. S. & Sweider, D. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Near infra-red astronomy with adaptive optics and laser guide stars at the Keck Observatory

Description: A laser guide star adaptive optics system is being built for the W. M. Keck Observatory`s 10-meter Keck II telescope. Two new near infra-red instruments will be used with this system: a high-resolution camera (NIRC 2) and an echelle spectrometer (NIRSPEC). The authors describe the expected capabilities of these instruments for high-resolution astronomy, using adaptive optics with either a natural star or a sodium-layer laser guide star as a reference. They compare the expected performance of th… more
Date: August 3, 1995
Creator: Max, C. E.; Gavel, D. T. & Olivier, S. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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