First results of the Starfire Optical Range 3.5-m telescope adaptive optics system: point spread functions and tracking performance

1998 ◽  
Author(s):  
David J. Lee ◽  
Brent L. Ellerbroek ◽  
Julian C. Christou
Keyword(s):  
Adaptive Optics ◽  
Tracking Performance ◽  
Optical Range ◽  
Point Spread Functions ◽  
Point Spread ◽  
First Results ◽  
Adaptive Optics System ◽  
System Point

scholarly journals Companion Detection Limits with Adaptive Optics Coronagraphy

2004 ◽  
Vol 202 ◽  
pp. 99-102
Author(s):  
B. R. Oppenheimer ◽  
R. G. Dekany ◽  
M. Troy ◽  
T. Hayward ◽  
B. Brandl
Keyword(s):  
Adaptive Optics ◽  
Focal Plane ◽  
Near Infrared ◽  
Dynamic Range ◽  
Infrared Camera ◽  
Nearby Star ◽  
Point Spread ◽  
Spread Function ◽  
Adaptive Optics System ◽  
Circular Disks

We present a study of the Palomar Adaptive Optics System and the PHARO near infrared camera in coronagraphic mode. The camera provides two different focal plane occulting masks–opaque circular disks 0.43 and 0.97″ across. Three different pupil plane apodizing masks (Lyot masks) are also provided. The six different combinations of Lyot mask and focal plane mask suppress differently the point spread function of a bright star centered on the focal plane mask. We obtained images of the bright nearby star Gliese 614 with all six different configurations in the K filter. We measured the dynamic range achievable with these configurations. Within 2.5″, the dynamic range is at least 8 magnitudes at the 5σ level and as high as 12 in a 1 s exposure. This represents a substantial gain over similar techniques without adaptive optics.

scholarly journals Debris Disk Science with the Palomar ExAO System: First Results

2013 ◽  
Vol 8 (S299) ◽  
pp. 72-73 ◽  
Author(s):  
Matthew Wahl ◽  
Stanimir Metchev ◽  
Rahul Patel ◽  
Eugene Serabyn ◽  
Dimitri Mawet ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Scattered Light ◽  
Outer Ring ◽  
Imaging Results ◽  
First Results ◽  
Debris Disk ◽  
First Time ◽  
Adaptive Optics System

AbstractWe present first imaging results from the PALM-3000 adaptive optics system and PHARO camera on the Hale 5 m telescope. Observations using a vector vortex coronagraph have given us direct detections of the two-ring dusty debris system around the star HD 141569. Our observations reveal the inner clearing in the disk to unprecedentedly small angular separations, and are the most sensitive yet at the H and K bands. We are for the first time able to measure and compare the colors of the scattered light in the inner and outer dust rings, and find that the outer ring is significantly bluer than the inner ring.

First results of an on-line adaptive optics system with atmospheric wavefront sensing by an artificial neural network

1992 ◽  
Vol 390 ◽  
pp. L41 ◽  
Author(s):  
M. Lloyd-Hart ◽  
P. Wizinowich ◽  
B. McLeod ◽  
D. Wittman ◽  
D. Colucci ◽  
...  
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Adaptive Optics ◽  
Wavefront Sensing ◽  
First Results ◽  
On Line ◽  
Artificial Neural ◽  
Adaptive Optics System

scholarly journals Wind-driven halo in high-contrast images

2020 ◽  
Vol 638 ◽  
pp. A98
Author(s):  
F. Cantalloube ◽  
O. J. D. Farley ◽  
J. Milli ◽  
N. Bharmal ◽  
W. Brandner ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Circumstellar Disks ◽  
Spectral Variation ◽  
Post Processing ◽  
Point Spread ◽  
Very Large Telescope ◽  
Spread Function ◽  
Processing Techniques ◽  
Fundamental Limitation ◽  
Adaptive Optics System

Context. The wind-driven halo is a feature that is observed in images that were delivered by the latest generation of ground-based instruments that are equipped with an extreme adaptive optics system and a coronagraphic device, such as SPHERE at the Very Large Telescope (VLT). This signature appears when the atmospheric turbulence conditions vary faster than the adaptive optics loop can correct for. The wind-driven halo is observed as a radial extension of the point spread function along a distinct direction (this is sometimes referred to as the butterfly pattern). When this is present, it significantly limits the contrast capabilities of the instrument and prevents the extraction of signals at close separation or extended signals such as circumstellar disks. This limitation is consequential because it contaminates the data for a substantial fraction of the time: about 30% of the data produced by the VLT/SPHERE instrument are affected by the wind-driven halo. Aims. This paper reviews the causes of the wind-driven halo and presents a method for analyzing its contribution directly from the scientific images. Its effect on the raw contrast and on the final contrast after post-processing is demonstrated. Methods. We used simulations and on-sky SPHERE data to verify that the parameters extracted with our method can describe the wind-driven halo in the images. We studied the temporal, spatial, and spectral variation of these parameters to point out its deleterious effect on the final contrast. Results. The data-driven analysis we propose provides information to accurately describe the wind-driven halo contribution in the images. This analysis confirms that this is a fundamental limitation of the finally reached contrast performance. Conclusions. With the established procedure, we will analyze a large sample of data delivered by SPHERE in order to propose post-processing techniques that are tailored to removing the wind-driven halo.

scholarly journals Laser Guide Star Adaptive Optics on the 1.5 Meter Telescope at the Starfire Optical Range

1994 ◽  
Vol 158 ◽  
pp. 293-295
Author(s):  
R. Q. Fugate
Keyword(s):  
Adaptive Optics ◽  
Full Width Half Maximum ◽  
Maximum Point ◽  
Laser Guide Star ◽  
Optical Range ◽  
Point Spread Functions ◽  
Visible Wavelengths ◽  
Guide Star ◽  
Laser Guide ◽  
System Operating

The Starfire Optical Range 1.5 m telescope is equipped with a 241 actuator adpative optics system operating at visible wavelengths. The system can use either natural or laser guide star beacons for sensing wavefront distortions induced by atmospheric turbulence. This paper describes the main parameters of the system and presents a few examples of experimental results. The best results are Strehl ratios of 0.64 (star beacon) and 0.48 (laser beacon), both having full-width-half-maximum point spread functions of 0.13 arc second (0.88 μm).

Photometric studies using the Starfire Optical Range adaptive optics system

1998 ◽  
Author(s):  
Albert Piterman ◽  
Zoran Ninkov ◽  
Brian S. Backer ◽  
Elliott P. Horch
Keyword(s):  
Adaptive Optics ◽  
Optical Range ◽  
Adaptive Optics System
Sign in / Sign up

Export Citation Format

Share Document