J/A+A/622/A169 A-PHOT, code for precision aperture photometry (Merlin+, 2019)
A-PHOT: a new, versatile code for precision aperture photometry.
Merlin E., Pilo S., Fontana A., Castellano M., Paris D., Roscani V.,
Santini P., Torelli M.
<Astron. Astrophys. 622, A169 (2019)>
=2019A&A...622A.169M 2019A&A...622A.169M (SIMBAD/NED BibCode)
ADC_Keywords: Models ; Photometry
Keywords: techniques: photometric - method: data analysis
Abstract:
We present A-PHOT, a new publicly available code for performing
aperture photometry on astronomical images, that is particularly well
suited for multi-band extragalactic surveys. A-PHOT estimates the
fluxes emitted by astronomical objects within a chosen set of circular
or elliptical apertures. Unlike other widely used codes, it runs on
predefined lists of positions, allowing for repeated measurements on
the same list of objects on different images. This can be very useful
when forced photometric measurement on a given position is needed.
A-PHOT can also estimate morphological parameters and a local
background flux, and compute on-the-fly individual optimized
elliptical apertures, in which the signal-to-noise ratio is maximized.
We check the performance of A-PHOT on both synthetic and real test
datasets: we explore a simulated case of a space-based high-resolution
imaging dataset, investigating the input parameter space to optimize
the accuracy of the performance, and we exploit the CANDELS
GOODS-South data to compare the A-PHOT measurements with those from
the survey legacy catalogs, finding good agreement overall. A-PHOT
proves to a useful and versatile tool for quickly extracting robust
and accurate photometric measurements and basic morphological
information of galaxies and stars, with the advantage of allowing for
various measurements of fluxes at any chosen position without the need
of a full detection run, and for determining the basic morphological
features of the sources.
Description:
A-PHOT is written in C, with a Python wrapper. In the tarball, the
user will find a documentation file in which the technical
specifications about installation and usage are given. Here we briefly
summarize the code features.
At variance with SExtractor, a-phot is designed to perform photometric
measurements requiring a detection catalog (and optionally a
segmentation map) as an input. Nevertheless, it is also possible to
internally compute some morphological parameters (semi-axis lengths,
ellipticity, position angle, and Kron radius), and to compute and
subtract a local background.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
aphot_2.1.3.tar 80 4000 A-PHOT code
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Acknowledgements:
Emiliano Merlin, emiliano.merlin(at)inaf.it
(End) Patricia Vannier [CDS] 06-Dec-2018