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Aperture Photometry Tool Versus SExtractor for Noncrowded Fields

Laher, Russ R. and Rebull, Luisa M. and Gorjian, Varoujan and Masci, Frank J. and Fowler, John W. and Grillmair, Carl and Surace, Jason and Mattingly, Sean and Jackson, Ed and Hacopeans, Eugean and Hamam, Nouhad and Groom, Steve and Teplitz, Harry and Mi, Wei and Helou, George and van Eyken, Julian C. and Dekany, Richard G. and Rahmer, Gustavo and Hale, David and Smith, Roger and Quimby, Robert M. and Ofek, Eran O. and Kasliwal, Mansi M. and Zolkower, Jeff and Velur, Viswa and Walters, Richard and Henning, John and Bui, Khanh and McKenna, Dan and Kulkarni, Shrinivas R. and Law, Nicholas M. (2012) Aperture Photometry Tool Versus SExtractor for Noncrowded Fields. Publications of the Astronomical Society of the Pacific, 124 (917). pp. 764-781. ISSN 0004-6280. doi:10.1086/666507.

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Outputs from new software program Aperture Photometry Tool (APT) are compared with similar outputs from SExtractor for sources extracted from R-band optical images acquired by the Palomar Transient Factory (PTF), infrared mosaics constructed from Spitzer Space Telescope images, and a processed visible/near-infrared image from the Hubble Legacy Archive (HLA). Two large samples from the PTF images are studied, each containing around 3 × 10^3 sources from noncrowded fields. The median values of source-intensity relative percentage differences between the two software programs, computed separately for two PTF samples, are +0.13% and +0.17%, with corresponding statistical dispersions of 1.43% and 1.84%, respectively. For the Spitzer mosaics, a similar large sample of extracted sources for each of channels 1–4 of Spitzer’s Infrared Array Camera (IRAC) are analyzed with two different sky annulus sizes, and we find that the median and modal values of source-intensity relative percentage differences between the two software programs are between -0.5% and +2.0%, and the corresponding statistical dispersions range from 1.4 to 6.7%, depending on the Spitzer IRAC channel and sky annulus. The results for the HLA image are mixed, as might be expected for a moderately crowded field. The comparisons for the three different kinds of images show that there is generally excellent agreement between APT and SExtractor. Differences in source-intensity uncertainty estimates for the PTF images amount to less than 3% for the PTF sources, and these are potentially caused by SExtractor’s omission of the sky background uncertainty term in the formula for source-intensity uncertainty, as well as differing methods of sky background estimation.

Item Type:Article
Related URLs:
URLURL TypeDescription
Laher, Russ R.0000-0003-2451-5482
Rebull, Luisa M.0000-0001-6381-515X
Masci, Frank J.0000-0002-8532-9395
Grillmair, Carl0000-0003-4072-169X
Surace, Jason0000-0001-7291-0087
Groom, Steve0000-0001-5668-3507
Teplitz, Harry0000-0002-7064-5424
Helou, George0000-0003-3367-3415
van Eyken, Julian C.0000-0003-2192-5371
Quimby, Robert M.0000-0001-9171-5236
Ofek, Eran O.0000-0002-6786-8774
Kasliwal, Mansi M.0000-0002-5619-4938
Walters, Richard0000-0002-1835-6078
Kulkarni, Shrinivas R.0000-0001-5390-8563
Law, Nicholas M.0000-0001-9380-6457
Additional Information:© 2012 Astronomical Society of the Pacific. Received 2010 March 29; accepted 2012 April 27; published 2012 June 18. This work is based in part on images acquired by the Palomar Transient Factory; in part on archival data obtained with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (NASA); and in part on observations made with the NASA/ESA Hubble Space Telescope and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESA), and the Canadian Astronomy Data Centre (CADC/NRC/CSA). This research made use of Montage, funded by NASA’s Earth Science Technology Office, Computation Technologies Project, under cooperative agreement NCC5-626 between NASA and the California Institute of Technology. Montage is maintained by the NASA/IPAC Infrared Science Archive.
Group:Infrared Processing and Analysis Center (IPAC), Palomar Transient Factory, Division of Geological and Planetary Sciences
Funding AgencyGrant Number
Subject Keywords:Data Analysis and Techniques
Issue or Number:917
Record Number:CaltechAUTHORS:20120925-132848017
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Official Citation:Aperture Photometry Tool Versus SExtractor for Noncrowded Fields Russ R. Laher, Luisa M. Rebull, Varoujan Gorjian, Frank J. Masci, John W. Fowler, Carl Grillmair, Jason Surace, Sean Mattingly, Ed Jackson, Eugean Hacopeans, Nouhad Hamam, Steve Groom, Harry Teplitz, Wei Mi, George Helou, Julian C. van Eyken, Nicholas M. Law, Richard G. Dekany, Gustavo Rahmer, David Hale, Roger Smith, Robert M. Quimby, Eran O. Ofek, Mansi M. Kasliwal, Jeff Zolkower, Viswa Velur, Richard Walters, John Henning, Khahn Bui, Dan McKenna and Shrinivas R. Kulkarni Publications of the Astronomical Society of the Pacific , Vol. 124, No. 917 (July 2012), pp. 764-781
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:34357
Deposited By: Ruth Sustaita
Deposited On:25 Sep 2012 21:46
Last Modified:09 Nov 2021 23:08

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