Abstract
We discuss data reduction techniques and results from the Simultaneous Differential Imager (SDI) implemented at the VLT (Lenzen et al. 2004a) 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 attenuated by a factor of >10 2. Non-trivial data reduction tools are necessary to pipeline the simultaneous differential imaging. Here we discuss a custom algorithm implemented in IDL to perform this reduction. The script performs basic data reduction tasks but also precisely aligns images taken in each of the filters using a custom shift and subtract routine. In our commissioning runs at the VLT and MMT, we achieved contrasts up to a factor of 45000 (ΔH=11.7) at a separation of 0.6" from the primary star. With this degree of attenuation, we should be able to image a 2-4 Jupiter mass planet at 5 AU around a 30 Myr star at 10 pc. We believe that our SDI images are the highest contrast astronomical images ever made from ground or space.
Original language | English (US) |
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Article number | 136 |
Pages (from-to) | 389-397 |
Number of pages | 9 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 5490 |
Issue number | PART 1 |
DOIs | |
State | Published - 2004 |
Event | Advancements in Adaptive Optics - Glasgow, United Kingdom Duration: Jun 21 2004 → Jun 25 2004 |
Keywords
- Adaptive optics
- Extrasolar planets
- High contrast imaging
- Simultaneous differential imaging
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering