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Aperture Photometry Tool

Laher, Russ R. and Gorjian, Varoujan and Rebull, Luisa M. and Masci, Frank J. and Fowler, John W. and Helou, George and Kulkarni, Shrinivas R. and Law, Nicholas M. (2012) Aperture Photometry Tool. Publications of the Astronomical Society of the Pacific, 124 (917). pp. 737-763. ISSN 0004-6280.

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Aperture Photometry Tool (APT) is software for astronomers and students interested in manually exploring the photometric qualities of astronomical images. It is a graphical user interface (GUI) designed to allow the image data associated with aperture photometry calculations for point and extended sources to be visualized and, therefore, more effectively analyzed. The finely tuned layout of the GUI, along with judicious use of color-coding and alerting, is intended to give maximal user utility and convenience. Simply mouse-clicking on a source in the displayed image will instantly draw a circular or elliptical aperture and sky annulus around the source and will compute the source intensity and its uncertainty, along with several commonly used measures of the local sky background and its variability. The results are displayed and can be optionally saved to an aperture-photometry-table file and plotted on graphs in various ways using functions available in the software. APT is geared toward processing sources in a small number of images and is not suitable for bulk processing a large number of images, unlike other aperture photometry packages (e.g., SExtractor). However, APT does have a convenient source-list tool that enables calculations for a large number of detections in a given image. The source-list tool can be run either in automatic mode to generate an aperture photometry table quickly or in manual mode to permit inspection and adjustment of the calculation for each individual detection. APT displays a variety of useful graphs with just the push of a button, including image histogram, x and y aperture slices, source scatter plot, sky scatter plot, sky histogram, radial profile, curve of growth, and aperture-photometry-table scatter plots and histograms. APT has many functions for customizing the calculations, including outlier rejection, pixel “picking” and “zapping,” and a selection of source and sky models. The radial-profile-interpolation source model, which is accessed via the radial-profile-plot panel, allows recovery of source intensity from pixels with missing data and can be especially beneficial in crowded fields.

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
Helou, George0000-0003-3367-3415
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 May 24; published 2012 July 10. We thank the beta testers. In particular, Tom Jarrett, Seppo Laine, Alberto Crespo-Noriega, Bill Reach, Jeonghee Rho, and Nancy Silbermann made numerous helpful suggestions. Inga Saathoff conducted invaluable beta testing in Germany. We are also grateful to Xiuqin Wu, Trey Roby, Loi Ly, and Booth Hartley for generous expert Java programming help and the use of some of their Java classes.We also thank BenneW. Holwerda for his insightful suggestions and manuscript corrections. Aperture Photometry Tool’s motto Inviso notitia and logo are copyright © 2012 by the California Institute of Technology.
Group:Infrared Processing and Analysis Center (IPAC)
Subject Keywords:Data Analysis and Techniques
Issue or Number:917
Record Number:CaltechAUTHORS:20120925-135301558
Persistent URL:
Official Citation:Aperture Photometry Tool Russ R. Laher, Varoujan Gorjian, Luisa M. Rebull, Frank J. Masci, John W. Fowler, George Helou, Shrinivas R. Kulkarni and Nicholas M. Law Publications of the Astronomical Society of the Pacific , Vol. 124, No. 917 (July 2012), pp. 737-763
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:34358
Deposited By: Ruth Sustaita
Deposited On:25 Sep 2012 21:37
Last Modified:03 Mar 2020 13:01

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