Physical Sciences and Mathematics | Open Access Articles

Sdss-Iv/Manga: Spectrophotometric Calibration Technique, Renbin Yan, Christy Tremonti, Matthew A. Bershady, David R. Law, David J. Schlegel, Kevin Bundy, Niv Drory, Nicholas Macdonald, Dmitry Bizyaev, Guillermo A. Blanc, Michael R. Blanton, Brian Cherinka, Arthur Eigenbrot, James E. Gunn, Paul Harding, David W. Hogg, José R. Sánchez-Gallego, Sebastian F. Sánchez, David A. Wake, Anne-Marie Weijmans, Ting Xiao, Kai Zhang

Physics and Astronomy Faculty Publications

Mapping Nearby Galaxies at Apache Point Observatory (MaNGA), one of three core programs in the Sloan Digital Sky Survey-IV, is an integral-field spectroscopic survey of roughly 10,000 nearby galaxies. It employs dithered observations using 17 hexagonal bundles of 2'' fibers to obtain resolved spectroscopy over a wide wavelength range of 3600–10300 Å. To map the internal variations within each galaxy, we need to perform accurate spectral surface photometry, which is to calibrate the specific intensity at every spatial location sampled by each individual aperture element of the integral field unit. The calibration must correct only for the flux loss due …

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A Catalog Of Visual-Like Morphologies In The 5 Candels Fields Using Deep Learning, M. Huertas-Company, R. Gravet, G. Cabrera-Vives, Pablo G. Pérez-González, J. Kartaltepe, Guillermo Barro, M. Bernardi, S. Mei, F. Shankar, P. Dimauro, E. F. Bell, Dale D. Kocevski, David C. Koo, Sandra M. Faber, Daniel H. Mcintosh

Physics and Astronomy Faculty Publications

We present a catalog of visual-like H-band morphologies of ~50.000 galaxies (H_f160w < 24.5) in the 5 CANDELS fields (GOODS-N, GOODS-S, UDS, EGS, and COSMOS). Morphologies are estimated using Convolutional Neural Networks (ConvNets). The median redshift of the sample is 〈z〉 ~ 1.25. The algorithm is trained on GOODS-S, for which visual classifications are publicly available, and then applied to the other 4 fields. Following the CANDELS main morphology classification scheme, our model retrieves for each galaxy the probabilities of having a spheroid or a disk, presenting an irregularity, being compact or a point source, and being unclassifiable. ConvNets are able to predict the fractions of votes given to a galaxy image with zero bias and ~10% scatter. The fraction of mis-classifications is …

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A Critical Assessment Of Stellar Mass Measurement Methods, Bahram Mobasher, Tomas Dahlen, Henry C. Ferguson, Viviana Acquaviva, Guillermo Barro, Steven L. Finkelstein, Adriano Fontana, Ruth Gruetzbauch, Seth Johnson, Yu Lu, Casey Papovich, Janine Pforr, Mara Salvato, Rachel S. Somerville, Tommy Wiklind, Stijn Wuyts, Matthew L.N. Ashby, Eric Bell, Christopher J. Conselice, Mark E. Dickinson, Sandra M. Faber, Giovanni Fazio, Kristian Finlator, Audrey Galametz, Eric Gawiser, Mauro Giavalisco, Andrea Grazian, Norman A. Grogin, Yicheng Guo, Nimish Hathi, Dale Kocevski, Anton M. Koekemoer, David C. Koo, Jeffrey A. Newman, Naveen Reddy, Paola Santini, Risa H. Wechsler

Physics and Astronomy Faculty Publications

This is the second paper in a series aimed at investigating the main sources of uncertainty in measuring the observable parameters in galaxies from their spectral energy distributions (SEDs). In the first paper we presented a detailed account of the photometric redshift measurements and an error analysis of this process. In this paper we perform a comprehensive study of the main sources of random and systematic error in stellar mass estimates for galaxies, and their relative contributions to the associated error budget. Since there is no prior knowledge of the stellar mass of galaxies (unlike their photometric redshifts), we use …

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Observing Strategy For The Sdss-Iv/Manga Ifu Galaxy Survey, David R. Law, Renbin Yan, Matthew A. Bershady, Kevin Bundy, Brian Cherinka, Niv Drory, Nicholas Macdonald, José R. Sánchez-Gallego, David R. Wake, Anne-Marie Weijmans, Michael R. Blanton, Mark A. Klaene, Sean M. Moran, Sebastian F. Sanchez, Kai Zhang

Physics and Astronomy Faculty Publications

Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) is an integral-field spectroscopic survey that is one of three core programs in the fourth-generation Sloan Digital Sky Survey (SDSS-IV). MaNGA's 17 pluggable optical fiber-bundle integral field units (IFUs) will observe a sample of 10,000 nearby galaxies distributed throughout the SDSS imaging footprint (focusing particularly on the North Galactic Cap). In each pointing these IFUs are deployed across a 3° field; they yield spectral coverage 3600−10300 Å at a typical resolution R ~ 2000, and sample the sky with 2'' diameter fiber apertures with a total bundle fill factor of 56%. Observing …

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P-Manga: Gradients In Recent Star Formation Histories As Diagnostics For Galaxy Growth And Death, Cheng Li, Enci Wang, Lin Lin, Matthew A. Bershady, Kevin Bundy, Christy A. Tremonti, Ting Xiao, Renbin Yan, Dmitry Bizyaev, Michael Blanton, Sabrina Cales, Brian Cherinka, Edmond Cheung, Niv Drory, Eric Emsellem, Hai Fu, Joseph Gelfand, David R. Law, Lahwai Lin, Nick Macdonald, Claudia Maraston, Karen L. Masters, Michael R. Merrifield, Kaike Pan, S. F. Sánchez, Donald P. Schneider, Daniel Thomas, David Wake, Lixin Wang, Anne-Marie Weijmans, David Wilkinson, Peter Yoachim, Kai Zhang, Tiantian Zheng

Physics and Astronomy Faculty Publications

We present an analysis of the data produced by the MaNGA prototype run (P-MaNGA), aiming to test how the radial gradients in recent star formation histories, as indicated by the 4000 Å break (D_n(4000)), Hδ absorption (EW(Hδ_A)), and Hα emission (EW(Hα)) indices, can be useful for understanding disk growth and star formation cessation in local galaxies. We classify 12 galaxies observed on two P-MaNGA plates as either centrally quiescent (CQ) or centrally star-forming (CSF), according to whether D_n(4000) measured in the central spaxel of each datacube exceeds 1.6. For …

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Stellar Masses From The Candels Survey: The Goods-South And Uds Fields, P. Santini, H. C. Ferguson, A. Fontana, B. Mobasher, G. Barro, M. Castellano, S. L. Finkelstein, A. Grazian, L. T. Hsu, B. Lee, S.-K. Lee, J. Pforr, M. Salvato, T. Wiklind, S. Wuyts, O. Almaini, M. C. Cooper, A. Galametz, B. Weiner, R. Amorin, K. Boutsia, C. J. Conselice, T. Dahlen, M. E. Dickinson, M. Giavalisco, N. A. Grogin, Y. Guo, N. P. Hathi, Dale D. Kocevski, A. M. Koekemoer, P. Kurczynski, E. Merlin, A. Mortlock, J. A. Newman, D. Paris, L. Pentericci, R. Simons, S. P. Willner

Physics and Astronomy Faculty Publications

We present the public release of the stellar mass catalogs for the GOODS-S and UDS fields obtained using some of the deepest near-IR images available, achieved as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey project. We combine the effort from 10 different teams, who computed the stellar masses using the same photometry and the same redshifts. Each team adopted their preferred fitting code, assumptions, priors, and parameter grid. The combination of results using the same underlying stellar isochrones reduces the systematics associated with the fitting code and other choices. Thanks to the availability of different estimates, we …

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The Manga Integral Field Unit Fiber Feed System For Thesloan 2.5 M Telescope, N. Drory, N. Macdonald, M. A. Bershady, K. Bundy, J. Gunn, D. R. Law, M. Smith, R. Stoll, C. A. Tremonti, D. A. Wake, Renbin Yan, A. M. Weijmans, N. Byler, B. Cherinka, F. Cope, A. Eigenbrot, P. Harding, D. Holder, J. Huehnerhoff, K. Jaehnig, T. C. Jansen, M. Klaene, A. M. Paat, J. Percival, C. Sayres

Physics and Astronomy Faculty Publications

We describe the design, manufacture, and performance of bare-fiber integral field units (IFUs) for the SDSS-IV survey Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) on the the Sloan 2.5 m telescope at Apache Point Observatory. MaNGA is a luminosity-selected integral-field spectroscopic survey of 10⁴ local galaxies covering 360–1030 nm at R ~ 2200. The IFUs have hexagonal dense packing of fibers with packing regularity of 3 μm (rms), and throughput of 96 ± 0.5% from 350 nm to 1 μm in the lab. Their sizes range from 19 to 127 fibers (3–7 hexagonal layers) using Polymicro …

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The Host Galaxies Of X-Ray Selected Active Galactic Nuclei To Z = 2.5: Structure, Star Formation, And Their Relationships From Candels And Herschel/Pacs, Dale D. Kocevski, D. J. Rosario, D. H. Mcintosh, A. Van Der Wel, J. Kartaltepe, P. Lang, P. Santini, S. Wuyts, D. Lutz, M. Rafelski, C. Villforth

Physics and Astronomy Faculty Publications

We study the relationship between the structure and star formation rate (SFR) of X-ray selected low and moderate luminosity active galactic nuclei (AGNs) in the two Chandra Deep Fields, using Hubble Space Telescope imaging from the Cosmic Assembly Near Infrared Extragalactic Legacy Survey (CANDELS) and deep far-infrared maps from the PEP+GOODS-Herschel survey. We derive detailed distributions of structural parameters and FIR luminosities from carefully constructed control samples of galaxies, which we then compare to those of the AGNs. At z ~ 1, AGNs show slightly diskier light profiles than massive inactive (non-AGN) galaxies, as well as modestly higher levels …

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Physics and Astronomy Faculty Publications

Physics and Astronomy Faculty Publications

Physics and Astronomy Faculty Publications

The Host Galaxies Of X-Ray Selected Active Galactic Nuclei To Z = 2.5: Structure, Star Formation, And Their Relationships From Candels And Herschel/Pacs, Dale D. Kocevski, D. J. Rosario, D. H. Mcintosh, A. Van Der Wel, J. Kartaltepe, P. Lang, P. Santini, S. Wuyts, D. Lutz, M. Rafelski, C. Villforth

Physics and Astronomy Faculty Publications