Physical Sciences and Mathematics | Open Access Articles

Sdss-Iv Manga: Spatially Resolved Star Formation Histories In Galaxies As A Function Of Galaxy Mass And Type, D. Goddard, D. Thomas, C. Maraston, K. Westfall, J. Etherington, R. Riffel, M. D. Mallmann, Z. Zheng, M. Argudo-Fernández, J. Lian, M. Bershady, K. Bundy, N. Drory, D. Law, Renbin Yan, D. Wake, A. Weijmans, D. Bizyaev, J. Brownstein, R. R. Lane, R. Maiolino, K. Masters, M. Merrifield, C. Nitschelm, K. Pan, A. Roman-Lopes, T. Storchi-Bergmann, D. P. Schneider

Physics and Astronomy Faculty Publications

We study the internal gradients of stellar population properties within 1.5 R_e for a representative sample of 721 galaxies, with stellar masses ranging between 10⁹ M_⊙ and 10^11.5 M_⊙ from the SDSS-IV MaNGA Integral-Field-Unit survey. Through the use of our full spectral fitting code firefly, we derive light- and mass-weighted stellar population properties and their radial gradients, as well as full star formation and metal enrichment histories. We also quantify the impact that different stellar population models and full spectral fitting routines have on the derived stellar population properties and the radial gradient measurements. In …

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Sdss-Iv Manga – The Spatially Resolved Transition From Star Formation To Quiescence, Francesco Belfiore, Roberto Maiolino, Claudia Maraston, Eric Emsellem, Matthew A. Bershady, Karen L. Masters, Dmitry Bizyaev, Médéric Boquien, Joel R. Brownstein, Kevin Bundy, Aleksandar M. Diamond-Stanic, Niv Drory, Timothy M. Heckman, David R. Law, Olena Malanushenko, Audrey Oravetz, Kaike Pan, Alexandre Roman-Lopes, Daniel Thomas, Anne-Marie Weijmans, Kyle B. Westfall, Renbin Yan

Physics and Astronomy Faculty Publications

Using spatially resolved spectroscopy from SDSS-IV MaNGA we have demonstrated that low ionization emission-line regions (LIERs) in local galaxies result from photoionization by hot evolved stars, not active galactic nuclei, hence tracing galactic region hosting old stellar population where, despite the presence of ionized gas, star formation is no longer occurring. LIERs are ubiquitous in both quiescent galaxies and in the central regions of galaxies where star formation takes place at larger radii. We refer to these two classes of galaxies as extended LIER (eLIER) and central LIER (cLIER) galaxies, respectively. cLIERs are late-type galaxies primarily spread across the green …

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The Quenching Timescale And Quenching Rate Of Galaxies, Jianhui Lian, Renbin Yan, Kai Zhang, Xu Kong

Physics and Astronomy Faculty Publications

The average star formation rate (SFR) in galaxies has been declining since the redshift of 2. A fraction of galaxies quench and become quiescent. We constrain two key properties of the quenching process: the quenching timescale and the quenching rate among galaxies. We achieve this by analyzing the galaxy number density profile in NUV−u color space and the distribution in NUV−u versus u − i color–color diagram with a simple toy-model framework. We focus on galaxies in three mass bins between 10¹⁰ and 10^10.6 M _⊙. In the NUV−u versus u − i color–color …

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Mid-Infrared Luminous Quasars In The Goods–Herschel Fields: A Large Population Of Heavily Obscured, Compton-Thick Quasars At Z ≈ 2, A. Del Moro, D. M. Alexander, F. E. Bauer, E. Daddi, Dale D. Kocevski, Daniel H. Mcintosh, F. Stanley, W. N. Brandt, D. Elbaz, C. M. Harrison, B. Luo, J. R. Mullaney, Y. Q. Xue

Physics and Astronomy Faculty Publications

We present the infrared (IR) and X-ray properties of a sample of 33 mid-IR luminous quasars (νL_6 μm ≥ 6 × 10⁴⁴ erg s⁻¹) at redshift z ≈ 1–3, identified through detailed spectral energy distribution analyses of distant star-forming galaxies, using the deepest IR data from Spitzer and Herschel in the GOODS–Herschel fields. The aim is to constrain the fraction of obscured, and Compton-thick (CT, N_H > 1.5 × 10²⁴ cm⁻²) quasars at the peak era of nuclear and star formation activities. Despite being very bright in the mid-IR band, ≈30 …

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The Jcmt Nearby Galaxies Legacy Survey – X. Environmental Effects On The Molecular Gas And Star Formation Properties Of Spiral Galaxies, Angus Mok, C. D. Wilson, J. Golding, B. E. Warren, F. P. Israel, S. Serjeant, J. H. Knapen, José R. Sánchez-Gallego, P. Barmby, G. J. Bendo, E. Rosolowsky, P. Van Der Werf

Physics and Astronomy Faculty Publications

We present a study of the molecular gas properties in a sample of 98 H I – flux selected spiral galaxies within ∼25 Mpc, using the CO J = 3 − 2 line observed with the James Clerk Maxwell Telescope. We use the technique of survival analysis to incorporate galaxies with CO upper limits into our results. Comparing the group and Virgo samples, we find a larger mean H₂ mass in the Virgo galaxies, despite their lower mean H I mass. This leads to a significantly higher H₂ to H I ratio for Virgo galaxies. Combining our data …

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Physics and Astronomy Faculty Publications

Physics and Astronomy Faculty Publications

The Quenching Timescale And Quenching Rate Of Galaxies, Jianhui Lian, Renbin Yan, Kai Zhang, Xu Kong

Physics and Astronomy Faculty Publications

Physics and Astronomy Faculty Publications

Physics and Astronomy Faculty Publications