Status of the 6.5m MMT Telescope laser adaptive optics system

The Laser Adaptive Optics system of the 6.5 m MMT telescope has now been commissioned with Ground Layer Adaptive Optics operations as a tool for astronomical science. In this mode the wavefronts sampled by each of five laser beacons are averaged, leading to an estimate of the aberration in the ground layer. The ground layer is then compensated by the deformable secondary mirror at 400 Hz. Image quality of 0.2-0.3 arc sec is delivered in the near infrared bands from 1.2-2.5 μm over a field of view of 2 arc minutes. Tomographic wavefront sensing tests in May 2010 produced open loop data necessary to streamline the software to generate a Laser Tomography Adaptive Optics (LTAO) reconstructor. In addition, we present the work being done to achieve optimal control PID wavefront control and thus increase the disturbance rejection frequency response for the system. Finally, we briefly describe plans to mount the ARIES near infrared imager and echelle spectrograph, which will support the 2 arc min ground-layer corrected field and will exploit the diffraction limit anticipated with LTAO.

[1]  F. Rigaut.  Ground Conjugate Wide Field Adaptive Optics for the ELTs , 2002 .

[2]  R. S. de Jong,et al.  PISCES: A Wide‐Field, 1–2.5 μm Camera for Large‐Aperture Telescopes , 2001 .

[3]  Thomas Eugene Stalcup.  Design and Construction of a Multiple Beam Laser Projector and Dynamically Refocused Wavefront Sensor , 2006 .

[4]  Keith Powell,et al.  Image motion correction using accelerometers at the MMT Observatory , 2008, Astronomical Telescopes + Instrumentation.

[5]  N. M. Milton,et al.  Experimental results of ground-layer and tomographic wavefront reconstruction from multiple laser guide stars. , 2006, Optics Express.

[6]  N. Hubin,et al.  Improving the seeing with wide-field adaptive optics in the near-infrared , 2005 .

[7]  James Roger P. Angel,et al.  ARIES: Arizona infrared imager and echelle spectrograph , 1998, Astronomical Telescopes and Instrumentation.

[8]  Christoph Baranec,et al.  Tomographic reconstruction of stellar wavefronts from multiple laser guide stars , 2006, SPIE Astronomical Telescopes + Instrumentation.

[9]  C. Baranec.  Astronomical Adaptive Optics using Multiple Laser Guide Stars , 2007 .

[10]  Armando Riccardi,et al.  First light of the 6.5-m MMT adaptive optics system , 2003, SPIE Optics + Photonics.

[11]  Georges,et al.  Dynamically refocused Rayleigh beacons for adaptive optics , 2003 .

[12]  Armando Riccardi,et al.  Adaptive secondary P30 prototype: laboratory results , 1998, Astronomical Telescopes and Instrumentation.

[13]  R. Biasi,et al.  The ESO Adaptive Optics Facility , 2006, SPIE Astronomical Telescopes + Instrumentation.

[14]  N. M. Milton,et al.  Wide-Field Image Compensation with Multiple Laser Guide Stars , 2009 .

[15]  Gustavo Arriagada,et al.  The Gemini South MCAO laser guide star facility: getting ready for first light , 2008, Astronomical Telescopes + Instrumentation.

[16]  Roberto Ragazzoni,et al.  Adaptive-optics corrections available for the whole sky , 2000, Nature.

[17]  E. Marchetti,et al.  Multi-Conjugate Adaptive Optics images of the Trapezium Cluster ⋆ , 2007, 0709.3994.

[18]  Philip M. Hinz,et al.  PCR: a PC-based wave front reconstructor for MMT-AO , 2008, Astronomical Telescopes + Instrumentation.

[19]  Michael Lloyd-Hart,et al.  Real-time atmospheric turbulence profile estimation using modal covariance measurements from multiple guide stars , 2007, SPIE Optical Engineering + Applications.

[20]  Bernard Delabre,et al.  On-sky Testing of the Multi-Conjugate Adaptive Optics Demonstrator , 2007 .

[21]  Jacques M. Beckers,et al.  Increasing the size of the isoplanatic patch with multiconjugate adaptive optics. , 1988 .

[22]  B. Welsh,et al.  Imaging Through Turbulence , 1996 .

[23]  N. M. Milton.  Tomographic Reconstruction of Wavefront Aberrations using Multiple Laser Guide Stars , 2009 .

[24]  Christoph Baranec,et al.  Astronomical imaging using ground-layer adaptive optics , 2007, SPIE Optical Engineering + Applications.

[25]  Jean-Pierre Véran,et al.  Modeling a GLAO system for the Gemini Observatory , 2006, SPIE Astronomical Telescopes + Instrumentation.

[26]  C. Baranec,et al.  First Tests of Wavefront Sensing with a Constellation of Laser Guide Beacons , 2005 .

[27]  Vidhya Vaitheeswaran,et al.  Implementation and on-sky results of an optimal wavefront controller for the MMT NGS adaptive optics system , 2010, Astronomical Telescopes + Instrumentation.

[28]  François Chassat.  Propagation optique a travers la turbulence atmospherique : etude modale de l'anisoplanetisme et application a l'optique adaptative , 1992 .

[29]  Michael Lloyd-Hart,et al.  Disk Harmonic Functions for Adaptive Optics Simulations , 2005 .