Correcting distortions in the infrared array camera during the cryogenic mission of the Spitzer Space Telescope

Carl J. Grillmair; Patrick J. Lowrance; Sean J. Carey; John R. Stauffer; James G. Ingalls; Jessica E. Krick; William J. Glaccum; Seppo Laine; Roberta Paladini; David L. Shupe; Schuyler D. Van Dyk

doi:10.1117/12.2313706

6 July 2018 Correcting distortions in the infrared array camera during the cryogenic mission of the Spitzer Space Telescope

Carl J. Grillmair, Patrick J. Lowrance, Sean J. Carey, John R. Stauffer, James G. Ingalls, Jessica E. Krick, William J. Glaccum, Seppo Laine, Roberta Paladini, David L. Shupe, Schuyler D. Van Dyk

Author Affiliations +

Proceedings Volume 10698, Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave; 106985D (2018) https://doi.org/10.1117/12.2313706
Event: SPIE Astronomical Telescopes + Instrumentation, 2018, Austin, Texas, United States

Abstract

We describe our ongoing efforts to model the field distortions of the Infrared Array Camera (IRAC) during the cryogenic portion of the Spitzer Space Telescope’s operations. We have compared over two million measured source positions in ~35,000 IRAC images with their positions in Gaia Data Release 1. Fitting 3^rd and 5^th order polynomials to the measured offsets, we find systematic uncertainties in IRAC-measured positions that are in the 50-60 milliarcsecond range for the 3.6 micron array, and 120-150 milliarcsecond range for the 4.5 micron array. A 5th-order fit does not appear to significantly improve the results over a 3rd order fit. However, this may be due at least partly to the failure of our current centroiding technique to account for variations in the Point Response Functions across each detector. We anticipate making several improvements in our continuing analysis, including (i) the refitting of the positions and position angles of each IRAC image using the Gaia catalog, (ii) making use of a less position-sensitive centroiding algorithm, (iii) correcting where possible for the proper motions of detected sources, and (iv) significantly increasing the number of source position measurements. Once finalized, the resulting distortion corrections will be incorporated into the headers of the archived images.

Citation Download Citation

Carl J. Grillmair, Patrick J. Lowrance, Sean J. Carey, John R. Stauffer, James G. Ingalls, Jessica E. Krick, William J. Glaccum, Seppo Laine, Roberta Paladini, David L. Shupe, and Schuyler D. Van Dyk "Correcting distortions in the infrared array camera during the cryogenic mission of the Spitzer Space Telescope", Proc. SPIE 10698, Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave, 106985D (6 July 2018); https://doi.org/10.1117/12.2313706

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available