Seminars at FGG
A Portable Adaptive Optics System for Faint-Star Exoplanet Imaging with the TNG
Speaker: Deqing Ren (California State Univ Northridge, USA (CSUN))
Date and time: 2019-03-22 11:30
Direct exoplanet imaging, with the ultimate goal of finding and characterizing exoplanets in the habitable zones, is one of the most important sciences in astronomy. With several tens of exoplanets detected by direct imaging, almost all of them are associated with bright stars (with a magnitude brighter than mv=9), since current extreme adaptive optics (EX-AO) are being using for exoplanet imaging. Recently, Bowler et al. successfully imaged a planetary-mass companion orbiting a faint star with an apparent magnitude mv=12.5, by used Keck telescope’s low-order adaptive optics. According to our knowledge, this is the only group that is using a low-order adaptive optics system for faint-star exoplanet imaging. In past years, we have successfully developed a Portable Adaptive Optics (PAO), which features moderate deformable mirror actuator number, compact size, low-cost, and can be quickly duplicated and used with any 4-meter class telescope. Our PAO was fully tested with the ESO 3.58-meter NTT (Chile), and Apache Point Observatory (APO) 3.5-m telescope (USA), as well as McDonald Observatory 2.7-m Smith telescope (USA). Our PAO, integrated our unique non-common optics path correction algorism and image-rotation subtraction data reduction technique, is dedicated for 4-meter class telescope exoplanet imaging. Recently, we sucessfully imaged the known exoplanet κ And b with the APO 3.5-m telescope at the 1 moderate seeing condition, which indicates that our PAO technique can be used for exoplanet scientific imaging. Since the current faint-star exoplanet imaging is focused on close-distance within 40pc, we have carefully selected over 800 unimaged faint and young stars in the 50200pc distance from the recently-released Gaia data as our long-term imaging survey program, which will ensure that our scientific targets have no overlap with current on-going exoplanet imaging programs. In this talk, I will present the PAO design philosophy, estimated performance, and the scientific observational goals with the 3.58-meter TNG.