Projects at IA-UNAM
FRIDA (inFRrared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) is being designed as a diffraction limited instrument with broad and narrow band imaging and integral field spectroscopy capabilities to operate in the wavelength range 0.9 – 2.5 mum. FRIDA is a collaborative project between the main GTC partners, namely, Spain, México and Florida. The main design characteristics of FRIDA are described in this contribution. FRIDA: Diffraction limited imaging and integral field spectroscopy with GTC (López, RevMex 2006)
Other projects/collaborations/interests Building on an extensive and successful experience in Adaptive Optics (AO) and on recent developments made in its funding nations, the Canada-France-Hawaii-Telescope Corporation (CFHT) is studying the VASAO concept: an integrated AO system that would allow diffraction limited imaging of the whole sky in the visible as well as in the infrared. At the core of VASAO, Pueo-Hou (the new Pueo) is built on Pueo, the current CFHT AO bonnette. Pueo will be refurbished and improved to be able to image the isoplanetic field at 700 nm with Strehl ratios of 30% or better, making possible imaging with a resolution of 50 milliarcseconds between 500 and 700nm, and at the telescope limit of diffraction above. The polychromatic tip-tilt laser guide star currently envisioned will be generated by a single 330nm mode-less laser, and the relative position of the 330nm and 589nm artificial stars created on the mesosphere by the 330nm excitation of the sodium layer will be monitored to provide the atmospheric tip-tilt along the line of sight, following the philosophy developed for the ELP-OA project. The feasibility study of VASAO will take most of 2006 in parallel with the development of a science case making the best possible use of the unique capabilities of the system, If the feasibility study is encouraging, VASAO development could start in 2007 for a full deployment on the sky by 2011-2012. VASAO: visible all sky adaptive optics (Veillet, SPIE 2006) Visible All Sky Adaptive Optics (VASAO web site @ CFHT) PhD work I started this PhD project in october 2001 under supervision of Dr. Renaud Foy at the Lyon Observatory in the “Middle-East” of France. As a part of the ELPOA (Etoile Laser Polychromatic pour l’Optique adaptative) project developped by the AIRI team (Astrophysics with Interferometric Resolution Imaging), my first mission is to build an experiment capable of measuring the atmospheric tilt chromatic variations due to the wavelength dependency of the atmospheric air refraction using a natural star. That’s why I am building ATTILA (ATmospheric TIlt LAb), an optical set-up dedicated to proving the feasibilty of the measurement of the tilts from their chromatic decomposition. Conference proceedings :Julien Girard & Renaud Foy ATTILA – measuring the atmospheric tilt from its chromaticity (SF2A 2002, eds. F. Combes, D. Barret, EDPS Conference Series in Astronomy and Astrophysics, in press.) Masters work: Instrumental developpments in astronomy mainly aim to improve our capacity to observe the Univers and all the objects involved. We want to see more, further, and more and more details to be able to explain astrophysical phenomenen. Research teams across the world are putting massive efforts towards high angular resolution improvements. Optical to infrared interferometry is the key element that will make direct imaging of earth-like extra-solar planets happen. The IONIC team of Grenoble is implementing integrated optics planar wave guide components. They combine up to three optical beams coming from independant telescopes. Their spatial filtering properties provide very accurate fringe visibility measurements. The purpose of my training was to test many of these 3T-combiners and to see how they respond to the needs in terms of transmission, wavelength dependency as well as their interferometric behaviour in the H and K atmospheric bands, etc. In the present report, I describe the characterization process of the components.
GUIELOA
A curvature AO system (a la Roddier, based on CFHT/PUEO) for the Mexican National 2.1m telescope in San Pedro Mártir. I am in charge of the optical conception of the final instrument to be installed at the telescope with all the optomechanical constraints and tolerancing it involves! I am also taking part in some optical lab/testing related work to debug the actual GUIELOA bench…
The first instrument for the GTC/AO. FRIDA is a IR Integral Fielfd spectrograph and Imager.
A project based on ELPOA (see PhD work bellow) at the CFHT.
The Polychromatic Laser Guide Star demonstrator (see PhD work bellow).
A high resolution generalized SCIDAR instrument to probe the atmospheric turbulence profile at low altitudes (towards better ground layer AO).
Optical turbulence profiling in the first kilometer with high altitude-resolution (R. Avila, MNRAS in preparation).
Polychromatic Laser Guide Star: Concept Demonstrator
Research
I arrived at la UNAM on october 26th 2006. I am learning the “know-how” of an optical engineer (paraxial calculous, Zemax, …) to assist Salvador Cuevas aka “Chavoc” in his work on the following two projects :
GUIELOA is the adaptive optics system for the 2.1m SPM telescope. This system has 19 sub-apertures, and is of curvature-type. It corrects for 8 Zernike terms. Guieloa is very similar to PUEO, the CFHT adaptive optics system. GUIELOA compensates atmospheric turbulence from the I band to the K band. For the J, H and K bands the corrected beam is sent to the TEQUILA IR camera. The I band is sent to a spectro-imager which uses a CCD in the visual band. Sampling for TEQUILA is 0.032 arcsec/pixel; the field is 33x 33 arcsec, with an expected resolution of 0.096 arcsec and a 0.4 Strehl ratio (for a seeing of 0.8 arcsec). For the I band the sampling is 0.019 arcsec/pixel, the field 20X20 arcsec and the resolution 0.057 arcsec with a 0.2 Strehl ratio (for a seeing of 0.8 arcsec). GUIELOA also performs as a coronograph using Lyot obscuration and phase masks. Among the planned applications of GUIELOA are the study of OB binary systems, the detection of close binary stars, and the study of disks, jets and other phenomena associated with young stars.GUIELOA: Adaptive Optics System for the 2.1-m SPM UNAM Telescope (Cuevas 2004, RevMex)
FRIDA
VASAO
ELP-OA
LOLAS
