The DOI matches its Crossref record; 43 of the 43 references it cites were found in a registry or an index.
A New Nonparametric Approach to Galaxy Morphological Classification
Open accessAbstract
We present two new nonparametric methods for quantifying galaxy morphology: the relative distribution of the galaxy pixel flux values (the Gini coefficient or G ) and the second-order moment of the brightest 20% of the galaxy's flux ( M 20 ). We test the robustness of G and M 20 to decreasing signal-to-noise ratio (S/N) and spatial resolution and find that both measures are reliable to within 10% for images with average S/N per pixel greater than 2 and resolutions better than 1000 and 500 pc, respectively. We have measured G and M 20 , as well as concentration ( C ), asymmetry ( A ), and clumpiness ( S ) in the rest-frame near-ultraviolet/optical wavelengths for 148 bright local "normal" Hubble-type galaxies (E–Sd) galaxies, 22 dwarf irregulars, and 73 0.05 < z < 0.25 ultraluminous infrared galaxies (ULIRGs). We find that most local galaxies follow a tight sequence in G - M 20 - C , where early types have high G and C and low M 20 and late-type spirals have lower G and C and higher M 20 . The majority of ULIRGs lie above the normal galaxy G - M 20 sequence because of their high G and M 20 values. Their high Gini coefficients arise from very bright nuclei, while the high second-order moments are produced by multiple nuclei and bright tidal tails. All of these features are signatures of recent and on-going mergers and interactions. We also find that in combination with A and S , G is more effective than C at distinguishing ULIRGs from the "normal" Hubble types. Finally, we measure the morphologies of 491.7 < z < 3.8 galaxies from HST NICMOS observations of the Hubble Deep Field North. We find that many of the z ∼ 2 galaxies possess G and A higher than expected from degraded images of local elliptical and spiral galaxies and have morphologies more like low-redshift ULIRGs.
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Detailed Structural Decomposition of Galaxy Images
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The First Data Release of the Sloan Digital Sky Survey
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The Relationship between Stellar Light Distributions of Galaxies and Their Formation Histories
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Rodriguez-Gomez, V., Snyder, G. F., Lotz, J. M., Nelson, D., Pillepich, A., Springel, V., Genel, S., Weinberger, R., Tacchella, S., Pakmor, R., et al. (2019) · Monthly Notices of the Royal Astronomical Society · doi:10.1093/mnras/sty3345 · Cited by 455
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Metadata
- Authors
- Lotz, J. M., Primack, J., & Madau, P.
- Venue
- The Astronomical Journal
- Publisher
- American Astronomical Society
- Published
- 2004-07
- Volume
- 128
- Issue
- 1
- Pages
- 163-182
- ISSN
- 0004-6256 (ISSN-L)
- 1538-3881
- OpenAlex
- W2058379217
- Cited by
- 832
- References
- 43
- FWCI
- 11.42
- Type
- journal article
- Language
- en
- Open access
- bronze
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