A Survey of Close, Young Stars with SDI at the VLT and MMT

Beth A. Biller, Laird M. Close, Elena Masciadri, Rainer Lenzen, Wolfgang Brandner, Donald McCarthy, Thomas Henning, Eric Nielsen, Markus Hartung
2005 Proceedings of the International Astronomical Union  
We discuss the preliminary results of a survey of young (<300 Myr), close (<50 pc) stars with the Simultaneous Differential Extrasolar Planet Imager (SDI) implemented at the VLT and the MMT. SDI uses a quad filter to take images simultaneously at 3 wavelengths surrounding the 1.62 µm methane bandhead found in the spectrum of cool brown dwarfs and gas giants. By performing a difference of images in these filters, speckle noise from the primary can be significantly attenuated, resulting in photon
more » ... noise limited data. In our survey data, we achieved H band contrasts >25000 (5σ ∆F1(1.575µm)>10 mag, ∆H>11.5 mag for a T6 spectral type) at a separation of 0.5" from the primary star. With this degree of attenuation, we should be able to image (5σ detection) a 2-4 Jupiter mass planet at 5 AU around a 30 Myr star at 10 pc. We are currently completing our survey of young, nearby stars, with complete datasets for 35 stars in the southern sky (VLT) and 7 stars in the northern sky (MMT). We believe that our SDI images are the highest contrast astronomical images ever made from ground or space for methane rich companions.
doi:10.1017/s1743921306009070 fatcat:kkaaj5hm3bd4pldbqrqerx6zbq