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SImMER: A Pipeline for Reducing and Analyzing Images of Stars

Savel, Arjun B. and Hirsch, Lea A. and Gill, Holden and Dressing, Courtney D. and Ciardi, David R. (2022) SImMER: A Pipeline for Reducing and Analyzing Images of Stars. Publications of the Astronomical Society of the Pacific, 134 (1042). Art. No. 124501. ISSN 0004-6280. doi:10.1088/1538-3873/aca4f9.

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We present the first public version of SImMER, an open-source Python reduction pipeline for astronomical images of point sources. Current capabilities include dark-subtraction, flat-fielding, sky-subtraction, image registration, FWHM measurement, contrast curve calculation, and table and plot generation. SImMER supports observations taken with the ShARCS camera on the Shane 3 m telescope and the PHARO camera on the Hale 5.1 m telescope. The modular nature of SImMER allows users to extend the pipeline to accommodate additional instruments with relative ease. One of the core functions of the pipeline is its image registration module, which is flexible enough to reduce saturated images and images of similar-brightness, resolved stellar binaries. Furthermore, SImMER can compute contrast curves for reduced images and produce publication-ready plots. The code is developed online at and is both pip- and conda-installable. We develop tutorials and documentation alongside the code and host them online. With SImMER, we aim to provide a community resource for accurate and reliable data reduction and analysis.

Item Type:Article
Related URLs:
URLURL TypeDescription
Savel, Arjun B.0000-0002-2454-768X
Hirsch, Lea A.0000-0001-8058-7443
Gill, Holden0000-0001-6171-7951
Dressing, Courtney D.0000-0001-8189-0233
Ciardi, David R.0000-0002-5741-3047
Additional Information:We acknowledge funding support from the Hellman Family Faculty Fund, the Sloan Foundation, and the David and Lucile Packard Foundation (grant 2019-69648). A.B. Savel acknowledges funding from the Heising-Simons Foundation. We thank the members of Prof. Courtney Dressing's research group for providing helpful feedback on the SImMER user experience. In particular, we thank Steven Giacalone for assisting as we benchmarked different contrast curve implementations. We gratefully acknowledge the staff at Lick and Palomar observatories for their work in operating and maintaining their respective instruments. Furthermore, we thank the anonymous reviewer for their careful reading of this manuscript that greatly improved its quality. This research made use of Photutils, an Astropy package for detection and photometry of astronomical sources (Bradley et al. 2022). This research has made use of NASA's Astrophysics Data System Bibliographic Services.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Hellman FellowshipUNSPECIFIED
Alfred P. Sloan FoundationUNSPECIFIED
David and Lucile Packard Foundation2019-69648
Heising-Simons FoundationUNSPECIFIED
Issue or Number:1042
Record Number:CaltechAUTHORS:20230105-911538600.6
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:118743
Deposited By: Research Services Depository
Deposited On:07 Feb 2023 20:15
Last Modified:07 Feb 2023 20:15

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