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Full-Text Articles in Physical Sciences and Mathematics
Wallaby Pre-Pilot And Pilot Survey: The Tully Fisher Relation In Eridanus, Hydra, Norma And Ngc4636 Fields, Helene Courtois, Alexandra Dupuy, Kristen Mcquinn, Lister Staveley-Smith, Danail Obreschkow, Edward Taylor, Benne Holwerda, Cullan Howlett, Frank Bigiel, Daniel Pomarede, Bi-Qing For, Tao Hong, Dane Kleiner, Thomas Jarrett, Ivy Wong, Jonghwan Rhee, Albert Bosma, Khaled Said, Tamara Davis, Igor Karachentsev, Matthew Colless, Renee Kraan-Korteweg, Nathan Deg, Kristine Spekkens, Karen Lee-Waddell, Jing Wang, Gerhardt R. Meurer
Wallaby Pre-Pilot And Pilot Survey: The Tully Fisher Relation In Eridanus, Hydra, Norma And Ngc4636 Fields, Helene Courtois, Alexandra Dupuy, Kristen Mcquinn, Lister Staveley-Smith, Danail Obreschkow, Edward Taylor, Benne Holwerda, Cullan Howlett, Frank Bigiel, Daniel Pomarede, Bi-Qing For, Tao Hong, Dane Kleiner, Thomas Jarrett, Ivy Wong, Jonghwan Rhee, Albert Bosma, Khaled Said, Tamara Davis, Igor Karachentsev, Matthew Colless, Renee Kraan-Korteweg, Nathan Deg, Kristine Spekkens, Karen Lee-Waddell, Jing Wang, Gerhardt R. Meurer
Faculty Scholarship
The WALLABY pilot survey has been conducted using the Australian SKA Pathfinder (ASKAP). The integrated 21-cm HI line spectra are formed in a very different manner compared to usual single-dish spectra Tully-Fisher measurements. It is thus extremely important to ensure that slight differences (e.g. biases due to missing flux) are quantified and understood in order to maximise the use of the large amount of data becoming available soon. This article is based on four fields for which the data are scientifically interesting by themselves. The pilot data discussed here consist of 614 galaxy spectra at a rest wavelength of 21cm. …
Wallaby Early Science − V. Askap Hi Imaging Of The Lyon Group Of Galaxies 351, B. Q. For, Lister Staveley-Smith, Tobias Westmeier, M. Whiting, S. -H. Oh, Baerbel Koribalski, Juan P. Madrid
Wallaby Early Science − V. Askap Hi Imaging Of The Lyon Group Of Galaxies 351, B. Q. For, Lister Staveley-Smith, Tobias Westmeier, M. Whiting, S. -H. Oh, Baerbel Koribalski, Juan P. Madrid
Physics and Astronomy Faculty Publications and Presentations
We present an HI study of the galaxy group LGG 351 using Widefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY) early science data observed with the Australian Square Kilometre Array Pathfinder (ASKAP). LGG 351 resides behind the M 83 group at a velocity range (cz) of ∼3500–4800 km s−1 within the rich Hydra-Centaurus overdensity region. We detect 40 sources with the discovery of a tidally interacting galaxy pair and two new HI sources that are not presented in previous optical catalogues. 23 out of 40 sources have new redshifts derived from the new HI data. This study is the largest …
Studying Galaxy Troughs And Ridges Using Weak Gravitational Lensing With The Kilo-Degree Survey, Margot M. Brouwer, Vasiliy Demchenko, Joachim Harnois-Déraps, Maciej Bilicki, Catherine Heymans, Henk Hoekstra, Konrad Kuijken, Mehmet Alpaslan, Sarah Brough, Yan Chuan Cai, Marcus V. Costa-Duarte, Andrej Dvornik, Thomas Erben, Hendrik Hildebrandt, Benne W. Holwerda, Peter Schneider, Cristóbal Sifón, Edo Van Uitert
Studying Galaxy Troughs And Ridges Using Weak Gravitational Lensing With The Kilo-Degree Survey, Margot M. Brouwer, Vasiliy Demchenko, Joachim Harnois-Déraps, Maciej Bilicki, Catherine Heymans, Henk Hoekstra, Konrad Kuijken, Mehmet Alpaslan, Sarah Brough, Yan Chuan Cai, Marcus V. Costa-Duarte, Andrej Dvornik, Thomas Erben, Hendrik Hildebrandt, Benne W. Holwerda, Peter Schneider, Cristóbal Sifón, Edo Van Uitert
Faculty Scholarship
We study projected underdensities in the cosmic galaxy density field known as 'troughs', and their overdense counterparts, which we call 'ridges'. We identify these regions using a bright sample of foreground galaxies from the photometric Kilo-Degree Survey (KiDS), specifically selected to mimic the spectroscopic Galaxy And Mass Assembly survey. Using background galaxies from KiDS, we measure the weak gravitational lensing profiles of the troughs/ridges. We quantify the amplitude of their lensing strength A as a function of galaxy density percentile rank P and galaxy overdensity δ, and find that the skewness in the galaxy density distribution is reflected in the …
Galaxy And Mass Assembly (Gama): The Signatures Of Galaxy Interactions As Viewed From Small-Scale Galaxy Clustering, M. L.P. Gunawardhana, P. Norberg, I. Zehavi, D. J. Farrow, J. Loveday, A. M. Hopkins, L. J.M. Davies, L. Wang, M. Alpaslan, J. Bland-Hawthorn, S. Brough, Benne W. Holwerda, M. S. Owers, A. H. Wright
Galaxy And Mass Assembly (Gama): The Signatures Of Galaxy Interactions As Viewed From Small-Scale Galaxy Clustering, M. L.P. Gunawardhana, P. Norberg, I. Zehavi, D. J. Farrow, J. Loveday, A. M. Hopkins, L. J.M. Davies, L. Wang, M. Alpaslan, J. Bland-Hawthorn, S. Brough, Benne W. Holwerda, M. S. Owers, A. H. Wright
Faculty Scholarship
Statistical studies of galaxy-galaxy interactions often utilize net change in physical properties of progenitors as a function of the separation between their nuclei to trace both the strength and the observable time-scale of their interaction. In this study, we use two-point auto-, cross-, and mark-correlation functions to investigate the extent to which small-scale clustering properties of star-forming galaxies can be used to gain physical insight into galaxy-galaxy interactions between galaxies of similar optical brightness and stellar mass. The Ha star formers, drawn from the highly spatially complete Galaxy And Mass Assembly (GAMA) survey, show an increase in clustering at small …
Galaxy And Mass Assembly: The G02 Field, Herschel-Atlas Target Selection And Data Release 3, I. K. Baldry, J. Liske, M. J.I. Brown, A. S.G. Robotham, S. P. Driver, L. Dunne, M. Alpaslan, S. Brough, M. E. Cluver, E. Eardley, D. J. Farrow, C. Heymans, H. Hildebrandt, A. M. Hopkins, L. S. Kelvin, J. Loveday, A. J. Moffett, P. Norberg, M. S. Owers, E. N. Taylor, A. H. Wright, S. P. Bamford, J. Bland-Hawthorn, N. Bourne, M. N. Bremer, M. Colless, C. J. Conselice, S. M. Croom, L. J.M. Davies, C. Foster, M. W. Grootes, Benne W. Holwerda, D. H. Jones
Galaxy And Mass Assembly: The G02 Field, Herschel-Atlas Target Selection And Data Release 3, I. K. Baldry, J. Liske, M. J.I. Brown, A. S.G. Robotham, S. P. Driver, L. Dunne, M. Alpaslan, S. Brough, M. E. Cluver, E. Eardley, D. J. Farrow, C. Heymans, H. Hildebrandt, A. M. Hopkins, L. S. Kelvin, J. Loveday, A. J. Moffett, P. Norberg, M. S. Owers, E. N. Taylor, A. H. Wright, S. P. Bamford, J. Bland-Hawthorn, N. Bourne, M. N. Bremer, M. Colless, C. J. Conselice, S. M. Croom, L. J.M. Davies, C. Foster, M. W. Grootes, Benne W. Holwerda, D. H. Jones
Faculty Scholarship
We describe data release 3 (DR3) of the Galaxy And Mass Assembly (GAMA) survey. The GAMA survey is a spectroscopic redshift and multiwavelength photometric survey in three equatorial regions each of 60.0 deg2 (G09, G12, and G15), and two southern regions of 55.7 deg2 (G02) and 50.6 deg2 (G23). DR3 consists of: the first release of data covering the G02 region and of data on H-ATLAS (Herschel - Astrophysical Terahertz Large Area Survey) sources in the equatorial regions; and updates to data on sources released in DR2. DR3 includes 154 809 sources with secure redshifts across four regions. A subset …
The Velocity Dispersion Function Of Very Massive Galaxy Clusters: Abell 2029 And Coma, Jubee Sohn, Margaret J. Geller, H. Jabran Zahid, Daniel G. Fabricant, Antonaldo Diaferio, Kenneth J. Rines
The Velocity Dispersion Function Of Very Massive Galaxy Clusters: Abell 2029 And Coma, Jubee Sohn, Margaret J. Geller, H. Jabran Zahid, Daniel G. Fabricant, Antonaldo Diaferio, Kenneth J. Rines
Physics & Astronomy
Based on an extensive redshift survey for galaxy clusters Abell 2029 and Coma, we measure the luminosity functions (LFs) and stellar mass functions (SMFs) for the entire cluster member galaxies. Most importantly, we measure the velocity dispersion functions (VDFs) for quiescent members. The MMT/Hectospec redshift survey for galaxies in A2029 identifies 982 spectroscopic members; for 838 members, we derive the central velocity dispersion from the spectroscopy. Coma is the only other cluster surveyed as densely. The LFs, SMFs, and VDFs for A2029 and Coma are essentially identical. The SMFs of the clusters are consistent with simulations. The A2029 and Coma …
The Ghosts Survey. I. Hubble Space Telescope Advanced Camera For Surveys Data., D. J. Radburn-Smith, R. S. De Jong, A. C. Seth, J. Bailin, E. F. Bell, T. M. Brown, J. S. Bullock, S. Courteau, J. J. Dalcanton, H. C. Ferguson, P. Goudfrooij, S. Holfeltz, Benne W. Holwerda, C. Purcell, J. Sick, D. Streich, M. Vlajic, D. B. Zucker
The Ghosts Survey. I. Hubble Space Telescope Advanced Camera For Surveys Data., D. J. Radburn-Smith, R. S. De Jong, A. C. Seth, J. Bailin, E. F. Bell, T. M. Brown, J. S. Bullock, S. Courteau, J. J. Dalcanton, H. C. Ferguson, P. Goudfrooij, S. Holfeltz, Benne W. Holwerda, C. Purcell, J. Sick, D. Streich, M. Vlajic, D. B. Zucker
Benne Holwerda
We present an overview of the GHOSTS survey, the largest study to date of the resolved stellar populations in the outskirts of disk galaxies. The sample consists of 14 disk galaxies within 17 Mpc, whose outer disks and halos are imaged with the Hubble Space Telescope Advanced Camera for Surveys (ACS). In the first paper of this series, we describe the sample, explore the benefits of using resolved stellar populations, and discuss our ACS F606W and F814W photometry. We use artificial star tests to assess completeness and use overlapping regions to estimate photometric uncertainties. The median depth of the survey …
Vlt/Vimos Observations Of An Occulting Galaxy Pair : Redshifts And Effective Extinction Curve., Benne W. Holwerda, T. Boker, J. J. Dalcanton, W. C. Keel, R. S. De Jong
Vlt/Vimos Observations Of An Occulting Galaxy Pair : Redshifts And Effective Extinction Curve., Benne W. Holwerda, T. Boker, J. J. Dalcanton, W. C. Keel, R. S. De Jong
Benne Holwerda
We present Very Large Telescope/Visible Multiobject Spectrograph Integral Field Unit observations of an occulting galaxy pair previously discovered in Hubble Space Telescope (HST) observations. The foreground galaxy is a low-inclination spiral disc, which causes clear attenuation features seen against the bright bulge and disc of the background galaxy. We find redshifts of z = 0.064 ± 0.003 and 0.065 for the foreground and background galaxy, respectively. This relatively small difference does not rule out gravitational interaction between the two galaxies. Emission line ratios point to a star-forming, not active galactic nuclei dominated foreground galaxy. We fit the Cardelli, Clayton and …
Galaxy And Mass Assembly (Gama) : End Of Survey Report And Data Release 2., J. Liske, I. K. Baldry, S. P. Driver, R. J. Tuffs, M. Alpaslan, E. Andrae, S. Brough, M. E. Cluver, M. W. Grootes, M. L. P. Gunawardhana, L. S. Kelvin, J. Loveday, A. S. G. Robotham, E. N. Taylor, S. P. Bamford, J. Bland-Hawthorn, M. J. I. Brown, M. J. Drinkwater, A. M. Hopkins, M. Meyer, P. Norberg, J. A. Peacock, N. K. Agius, S. K. Andrews, A. E. Bauer, J. H. Y. Ching, M. Colless, C. J. Conselice, S. M. Croom, L. J. M. Davies, R. De Propris, L. Dunne, E. M. Eardley, S. Ellis, C. Foster, C. S. Frenk, B. Haußler, Benne W. Holwerda, C. Howlett, H. Ibarra, M. J. Jarvis, D. H. Jones, P. R. Kafle, C. G. Lacey, R. Lange, M. Lara-Lopez, Angel R. Lopez-Sanchez, S. J. Maddox, B. F. Madore, T. Mcnaught-Roberts, A. J. Moffett, R. C. Nichol, M. S. Owers, D. Palamara, S. J. Penny, S. Phillipps, K. A. Pimbblet, C. C. Popescu, M. Prescott, R. Proctor, E. M. Sadler, A. E. Sansom, M. Seibert, R. Sharp, W. Sutherland, J. A. Vazquez-Mata, E. Van Kampen, S. M. Wilkins, R. Williams, A. H. Wright
Galaxy And Mass Assembly (Gama) : End Of Survey Report And Data Release 2., J. Liske, I. K. Baldry, S. P. Driver, R. J. Tuffs, M. Alpaslan, E. Andrae, S. Brough, M. E. Cluver, M. W. Grootes, M. L. P. Gunawardhana, L. S. Kelvin, J. Loveday, A. S. G. Robotham, E. N. Taylor, S. P. Bamford, J. Bland-Hawthorn, M. J. I. Brown, M. J. Drinkwater, A. M. Hopkins, M. Meyer, P. Norberg, J. A. Peacock, N. K. Agius, S. K. Andrews, A. E. Bauer, J. H. Y. Ching, M. Colless, C. J. Conselice, S. M. Croom, L. J. M. Davies, R. De Propris, L. Dunne, E. M. Eardley, S. Ellis, C. Foster, C. S. Frenk, B. Haußler, Benne W. Holwerda, C. Howlett, H. Ibarra, M. J. Jarvis, D. H. Jones, P. R. Kafle, C. G. Lacey, R. Lange, M. Lara-Lopez, Angel R. Lopez-Sanchez, S. J. Maddox, B. F. Madore, T. Mcnaught-Roberts, A. J. Moffett, R. C. Nichol, M. S. Owers, D. Palamara, S. J. Penny, S. Phillipps, K. A. Pimbblet, C. C. Popescu, M. Prescott, R. Proctor, E. M. Sadler, A. E. Sansom, M. Seibert, R. Sharp, W. Sutherland, J. A. Vazquez-Mata, E. Van Kampen, S. M. Wilkins, R. Williams, A. H. Wright
Benne Holwerda
The Galaxy And Mass Assembly (GAMA) survey is one of the largest contemporary spectroscopic surveys of low redshift galaxies. Covering an area of ∼286 deg2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, we have collected spectra and reliable redshifts for 238 000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope. In addition, we have assembled imaging data from a number of independent surveys in order to generate photometry spanning the wavelength range 1 nm–1 m. Here, we report on the recently completed spectroscopic survey and present a series of diagnostics to assess …
Galaxy And Mass Assembly (Gama) Blended Spectra Catalogue : Strong Galaxy–Galaxy Lens And Occulting Galaxy Pair Candidates., Benne W. Holwerda, I. K. Baldry, M. Alpaslan, A. E. Bauer, J. Bland-Hawthorn, S. Brough, M. J. I. Brown, M. E. Cluver, C. J. Conselice, S. P. Driver, A. M. Hopkins, D. H. Jones, Angel R. Lopez-Sanchez, J. Loveday, M. J. Meyer, A. Moffett
Galaxy And Mass Assembly (Gama) Blended Spectra Catalogue : Strong Galaxy–Galaxy Lens And Occulting Galaxy Pair Candidates., Benne W. Holwerda, I. K. Baldry, M. Alpaslan, A. E. Bauer, J. Bland-Hawthorn, S. Brough, M. J. I. Brown, M. E. Cluver, C. J. Conselice, S. P. Driver, A. M. Hopkins, D. H. Jones, Angel R. Lopez-Sanchez, J. Loveday, M. J. Meyer, A. Moffett
Benne Holwerda
We present the catalogue of blended galaxy spectra from the Galaxy And Mass Assembly (GAMA) survey. These are cases where light from two galaxies are significantly detected in a single GAMA fibre. Galaxy pairs identified from their blended spectrum fall into two principal classes: they are either strong lenses, a passive galaxy lensing an emission-line galaxy; or occulting galaxies, serendipitous overlaps of two galaxies, of any type. Blended spectra can thus be used to reliably identify strong lenses for follow-up observations (high-resolution imaging) and occulting pairs, especially those that are a late-type partly obscuring an early-type galaxy which are of …
Wise X Supercosmos Photometric Redshift Catalog : 20 Million Galaxies Over 3pi Steradians., Maciej Bilicki, John A. Peacock, T. H. Jarrett, Michelle Cluver, Natasha Maddox, Michael J. I. Brown, Edward N. Taylor, Nigel C. Hambly, Aleksandra Solarz, Benne W. Holwerda, Ivan K. Baldry, Jon Loveday, Amanda J. Moffett, Andrew M. Hopkins, Simon P. Driver, Mehmet Alpaslan, Joss Bland-Hawthorn
Wise X Supercosmos Photometric Redshift Catalog : 20 Million Galaxies Over 3pi Steradians., Maciej Bilicki, John A. Peacock, T. H. Jarrett, Michelle Cluver, Natasha Maddox, Michael J. I. Brown, Edward N. Taylor, Nigel C. Hambly, Aleksandra Solarz, Benne W. Holwerda, Ivan K. Baldry, Jon Loveday, Amanda J. Moffett, Andrew M. Hopkins, Simon P. Driver, Mehmet Alpaslan, Joss Bland-Hawthorn
Benne Holwerda
We cross-match the two currently largest all-sky photometric catalogs—mid-infrared Wide-field Infrared Survey Explorer and SuperCOSMOS scans of UKST/POSS-II photographic plates—to obtain a new galaxy sample that covers 3π steradians. In order to characterize and purify the extragalactic data set, we use external GAMA and Sloan Digital Sky Survey spectroscopic information to define quasar and star loci in multicolor space, aiding the removal of contamination from our extended source catalog. After appropriate data cleaning, we obtain a deep wide-angle galaxy sample that is approximately 95% pure and 90% complete at high Galactic latitudes. The catalog contains close to 20 million galaxies …
Wise X Supercosmos Photometric Redshift Catalog : 20 Million Galaxies Over 3pi Steradians., Maciej Bilicki, John A. Peacock, T. H. Jarrett, Michelle Cluver, Natasha Maddox, Michael J. I. Brown, Edward N. Taylor, Nigel C. Hambly, Aleksandra Solarz, Benne W. Holwerda, Ivan K. Baldry, Jon Loveday, Amanda J. Moffett, Andrew M. Hopkins, Simon P. Driver, Mehmet Alpaslan, Joss Bland-Hawthorn
Wise X Supercosmos Photometric Redshift Catalog : 20 Million Galaxies Over 3pi Steradians., Maciej Bilicki, John A. Peacock, T. H. Jarrett, Michelle Cluver, Natasha Maddox, Michael J. I. Brown, Edward N. Taylor, Nigel C. Hambly, Aleksandra Solarz, Benne W. Holwerda, Ivan K. Baldry, Jon Loveday, Amanda J. Moffett, Andrew M. Hopkins, Simon P. Driver, Mehmet Alpaslan, Joss Bland-Hawthorn
Faculty Scholarship
We cross-match the two currently largest all-sky photometric catalogs—mid-infrared Wide-field Infrared Survey Explorer and SuperCOSMOS scans of UKST/POSS-II photographic plates—to obtain a new galaxy sample that covers 3π steradians. In order to characterize and purify the extragalactic data set, we use external GAMA and Sloan Digital Sky Survey spectroscopic information to define quasar and star loci in multicolor space, aiding the removal of contamination from our extended source catalog. After appropriate data cleaning, we obtain a deep wide-angle galaxy sample that is approximately 95% pure and 90% complete at high Galactic latitudes. The catalog contains close to 20 million galaxies …
Hecs-Sz: The Hectospec Survey Of Sunyaev-Zeldovich-Selected Clusters, Kenneth J. Rines, Margaret J. Geller, Antonaldo Diaferio, Ho Seong Hwang
Hecs-Sz: The Hectospec Survey Of Sunyaev-Zeldovich-Selected Clusters, Kenneth J. Rines, Margaret J. Geller, Antonaldo Diaferio, Ho Seong Hwang
Physics & Astronomy
We estimate cluster masses and velocity dispersions for 123 clusters from optical spectroscopy to compare the Sunyaev–Zeldovich (SZ) mass proxy and dynamical masses. Our new survey, HeCS-SZ (Hectospec Cluster Survey of SZ-selected clusters), includes 7721 new or remeasured redshifts from MMT/Hectospec observations of 21 SZ-selected clusters at redshifts z = 0.05–0.20. We supplement the Hectospec data with spectra from the Sloan Digital Sky Survey (SDSS) and cluster data from the Cluster Infall Regions in SDSS project and the Hectospec Cluster Survey, our Hectospec survey of clusters selected by X-ray flux. We measure the scaling relation between velocity dispersion and SZ …
Galaxy And Mass Assembly (Gama) : End Of Survey Report And Data Release 2., J. Liske, I. K. Baldry, S. P. Driver, R. J. Tuffs, M. Alpaslan, E. Andrae, S. Brough, M. E. Cluver, M. W. Grootes, M. L. P. Gunawardhana, L. S. Kelvin, J. Loveday, A. S. G. Robotham, E. N. Taylor, S. P. Bamford, J. Bland-Hawthorn, M. J. I. Brown, M. J. Drinkwater, A. M. Hopkins, M. Meyer, P. Norberg, J. A. Peacock, N. K. Agius, S. K. Andrews, A. E. Bauer, J. H. Y. Ching, M. Colless, C. J. Conselice, S. M. Croom, L. J. M. Davies, R. De Propris, L. Dunne, E. M. Eardley, S. Ellis, C. Foster, C. S. Frenk, B. Haußler, Benne W. Holwerda, C. Howlett, H. Ibarra, M. J. Jarvis, D. H. Jones, P. R. Kafle, C. G. Lacey, R. Lange, M. Lara-Lopez, Angel R. Lopez-Sanchez, S. J. Maddox, B. F. Madore, T. Mcnaught-Roberts, A. J. Moffett, R. C. Nichol, M. S. Owers, D. Palamara, S. J. Penny, S. Phillipps, K. A. Pimbblet, C. C. Popescu, M. Prescott, R. Proctor, E. M. Sadler, A. E. Sansom, M. Seibert, R. Sharp, W. Sutherland, J. A. Vazquez-Mata, E. Van Kampen, S. M. Wilkins, R. Williams, A. H. Wright
Galaxy And Mass Assembly (Gama) : End Of Survey Report And Data Release 2., J. Liske, I. K. Baldry, S. P. Driver, R. J. Tuffs, M. Alpaslan, E. Andrae, S. Brough, M. E. Cluver, M. W. Grootes, M. L. P. Gunawardhana, L. S. Kelvin, J. Loveday, A. S. G. Robotham, E. N. Taylor, S. P. Bamford, J. Bland-Hawthorn, M. J. I. Brown, M. J. Drinkwater, A. M. Hopkins, M. Meyer, P. Norberg, J. A. Peacock, N. K. Agius, S. K. Andrews, A. E. Bauer, J. H. Y. Ching, M. Colless, C. J. Conselice, S. M. Croom, L. J. M. Davies, R. De Propris, L. Dunne, E. M. Eardley, S. Ellis, C. Foster, C. S. Frenk, B. Haußler, Benne W. Holwerda, C. Howlett, H. Ibarra, M. J. Jarvis, D. H. Jones, P. R. Kafle, C. G. Lacey, R. Lange, M. Lara-Lopez, Angel R. Lopez-Sanchez, S. J. Maddox, B. F. Madore, T. Mcnaught-Roberts, A. J. Moffett, R. C. Nichol, M. S. Owers, D. Palamara, S. J. Penny, S. Phillipps, K. A. Pimbblet, C. C. Popescu, M. Prescott, R. Proctor, E. M. Sadler, A. E. Sansom, M. Seibert, R. Sharp, W. Sutherland, J. A. Vazquez-Mata, E. Van Kampen, S. M. Wilkins, R. Williams, A. H. Wright
Faculty Scholarship
The Galaxy And Mass Assembly (GAMA) survey is one of the largest contemporary spectroscopic surveys of low redshift galaxies. Covering an area of ∼286 deg2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, we have collected spectra and reliable redshifts for 238 000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope. In addition, we have assembled imaging data from a number of independent surveys in order to generate photometry spanning the wavelength range 1 nm–1 m. Here, we report on the recently completed spectroscopic survey and present a series of diagnostics to assess its final state and the quality of the redshift data. We also describe a number of survey aspects and procedures, or updates thereof, including changes to the input catalogue, redshifting and re-redshifting, and the derivation of ultraviolet, optical and near-infrared photometry. Finally, we present the second public release of GAMA data. In this release, we provide input catalogue and targeting information, spectra, redshifts, ultraviolet, optical and near-infrared photometry, single-component Sérsic fits, stellar masses, Hα-derived star formation rates, environment information, and group properties for all galaxies with r < 19.0 mag in two of our survey regions, and for all galaxies with r < 19.4 mag in a third region (72 225 objects in total). The data base serving these data is available at http://www.gama-survey.org/.
Galaxy And Mass Assembly (Gama) Blended Spectra Catalogue : Strong Galaxy–Galaxy Lens And Occulting Galaxy Pair Candidates., Benne W. Holwerda, I. K. Baldry, M. Alpaslan, A. E. Bauer, J. Bland-Hawthorn, S. Brough, M. J. I. Brown, M. E. Cluver, C. J. Conselice, S. P. Driver, A. M. Hopkins, D. H. Jones, Angel R. Lopez-Sanchez, J. Loveday, M. J. Meyer, A. Moffett
Galaxy And Mass Assembly (Gama) Blended Spectra Catalogue : Strong Galaxy–Galaxy Lens And Occulting Galaxy Pair Candidates., Benne W. Holwerda, I. K. Baldry, M. Alpaslan, A. E. Bauer, J. Bland-Hawthorn, S. Brough, M. J. I. Brown, M. E. Cluver, C. J. Conselice, S. P. Driver, A. M. Hopkins, D. H. Jones, Angel R. Lopez-Sanchez, J. Loveday, M. J. Meyer, A. Moffett
Faculty Scholarship
We present the catalogue of blended galaxy spectra from the Galaxy And Mass Assembly (GAMA) survey. These are cases where light from two galaxies are significantly detected in a single GAMA fibre. Galaxy pairs identified from their blended spectrum fall into two principal classes: they are either strong lenses, a passive galaxy lensing an emission-line galaxy; or occulting galaxies, serendipitous overlaps of two galaxies, of any type. Blended spectra can thus be used to reliably identify strong lenses for follow-up observations (high-resolution imaging) and occulting pairs, especially those that are a late-type partly obscuring an early-type galaxy which are of …
Detection Of A Distinct Metal-Poor Stellar Halo In The Early-Type Galaxy Ngc 3115*, Mark Peacock, Jay Strader, Aaron Romanowsky, Jean Brodie
Detection Of A Distinct Metal-Poor Stellar Halo In The Early-Type Galaxy Ngc 3115*, Mark Peacock, Jay Strader, Aaron Romanowsky, Jean Brodie
Faculty Publications
We present the resolved stellar populations in the inner and outer halo of the nearby lenticular galaxy NGC 3115. Using deep Hubble Space Telescope observations, we analyze stars 2 mag fainter than the tip of the red giant branch (TRGB). We study three fields along the minor axis of this galaxy, 19, 37, and 54 kpc from its center—corresponding to 7, 14, and 21 effective radii (re ). Even at these large galactocentric distances, all of the fields are dominated by a relatively enriched population, with the main peak in the metallicity distribution decreasing with radius from [Z/H] ~ –0.5 …
A Redshift Survey Of The Strong-Lensing Cluster Abell 383, Margaret J. Geller, Ho Seong Hwang, Antonaldo Diaferio, Michael J. Kurtz, Dan Coe, Kenneth J. Rines
A Redshift Survey Of The Strong-Lensing Cluster Abell 383, Margaret J. Geller, Ho Seong Hwang, Antonaldo Diaferio, Michael J. Kurtz, Dan Coe, Kenneth J. Rines
Physics & Astronomy
Abell 383 is a famous rich cluster (z = 0.1887) imaged extensively as a basis for intensive strong- and weak-lensing studies. Nonetheless, there are few spectroscopic observations. We enable dynamical analyses by measuring 2360 new redshifts for galaxies with r Petro ≤ 20.5 and within 50' of the Brightest Cluster Galaxy (BCG; R.A.2000 = 42014125, decl.2000 = –03529228). We apply the caustic technique to identify 275 cluster members within 7 h –1 Mpc of the hierarchical cluster center. The BCG lies within –11 ± 110 km s–1 and 21 ± 56 h –1 kpc of the …
New Observations Of Z~7 Galaxies: Evidence For A Patch Reionization, L. Pentericci, E. Vanzella, A. Fontana, M. Castellano, T. Treu, A. Mesinger, M. Dijkstra, A. Grazian, B. Bradac, S. Cristiani, A. Galametz, Mauro Giavalisco, E. Giallongo, R. Maiolino, D. Paris, P. Santini
New Observations Of Z~7 Galaxies: Evidence For A Patch Reionization, L. Pentericci, E. Vanzella, A. Fontana, M. Castellano, T. Treu, A. Mesinger, M. Dijkstra, A. Grazian, B. Bradac, S. Cristiani, A. Galametz, Mauro Giavalisco, E. Giallongo, R. Maiolino, D. Paris, P. Santini
Mauro Giavalisco
We present new results from our search for z∼ 7 galaxies from deep spectroscopic observations of candidate z-dropouts in the CANDELS fields. Despite the extremely low flux limits achieved by our sensitive observations, only 2 galaxies have robust redshift identifications, one from its Lyα emission line at z=6.65, the other from its Lyman-break, i.e. the continuum discontinuity at the Lyα wavelength consistent with a redshift 6.42, but with no emission line. In addition, for 23 galaxies we present deep limits in the Lyα EW derived from the non detections in ultra-deep observations. Using this new data as well as previous …
A 52 Hours Vlt/Fors2 Spectrum Of A Bright Z ~ 7 Hudf Galaxy: No Lya Emission, E. Venzella, A. Fontana, L. Pentericci, M. Castellano, A. Grazian, Mauro Giavalisco, M. Nonino, S. Cristiani, G. Zamorani, C. Vignali
A 52 Hours Vlt/Fors2 Spectrum Of A Bright Z ~ 7 Hudf Galaxy: No Lya Emission, E. Venzella, A. Fontana, L. Pentericci, M. Castellano, A. Grazian, Mauro Giavalisco, M. Nonino, S. Cristiani, G. Zamorani, C. Vignali
Mauro Giavalisco
Aims: We aim to determine the redshift of GDS_1408, the most solid z _ 7 galaxy candidate lying in the Hubble Ultra Deep Field. Methods: We have used all the VLT spectra of GDS_1408 collected by us and two other groups with FORS2 at VLT in the last five years, for a total integration time of 52hr. The combined spectrum is the deepest ever obtained of a galaxy in the Reionization epoch. Results: We do not detect any emission line or continuum over the whole wavelength range, up to 10100Å. Based on an accurate set of simulations, we are able …
The Relation Between Star Formation Rate And Stellar Mass For Galaxies At 3.5 < Z < 6.5 In Candels, Brett Salmon, Casey Papovich, Steven L. Finkelstein, Vithal Tilvi, Kristian Flinator, Peter Behroozi, Tomas Dahlen, Romeel Dave, Avishai Dekel, Mark Dickinson, Henry C. Ferguson, Mauro Giavalisco, James Long, Yu Lu, Bahram Mobasher, Naveen Reddy, Rachel S. Somerville, Risa H. Wechsler
The Relation Between Star Formation Rate And Stellar Mass For Galaxies At 3.5 < Z < 6.5 In Candels, Brett Salmon, Casey Papovich, Steven L. Finkelstein, Vithal Tilvi, Kristian Flinator, Peter Behroozi, Tomas Dahlen, Romeel Dave, Avishai Dekel, Mark Dickinson, Henry C. Ferguson, Mauro Giavalisco, James Long, Yu Lu, Bahram Mobasher, Naveen Reddy, Rachel S. Somerville, Risa H. Wechsler
Mauro Giavalisco
No abstract provided.
Vlt/Vimos Observations Of An Occulting Galaxy Pair : Redshifts And Effective Extinction Curve., Benne W. Holwerda, T. Boker, J. J. Dalcanton, W. C. Keel, R. S. De Jong
Vlt/Vimos Observations Of An Occulting Galaxy Pair : Redshifts And Effective Extinction Curve., Benne W. Holwerda, T. Boker, J. J. Dalcanton, W. C. Keel, R. S. De Jong
Faculty Scholarship
We present Very Large Telescope/Visible Multiobject Spectrograph Integral Field Unit observations of an occulting galaxy pair previously discovered in Hubble Space Telescope (HST) observations. The foreground galaxy is a low-inclination spiral disc, which causes clear attenuation features seen against the bright bulge and disc of the background galaxy. We find redshifts of z = 0.064 ± 0.003 and 0.065 for the foreground and background galaxy, respectively. This relatively small difference does not rule out gravitational interaction between the two galaxies. Emission line ratios point to a star-forming, not active galactic nuclei dominated foreground galaxy. We fit the Cardelli, Clayton and …
Bl Lacertae Objects Beyond Redshift 1.3 - Uv-To-Nir Photometry And Photometric Redshift For Fermi/Lat Blazars, A. Rau, P. Schady, J. Greiner, M. Salvato, M. Ajello, E. Bottacini, N. Gehrels, P.M. J. Afonso, J. Elliott, R Filgas, D A. Kann, S Klose, T Krühler, M Nardini, A Nicuesa Guelbenzu, F Olivares E., A Rossi, V Sudilovsky, A C. Updike, Dieter H. Hartmann
Bl Lacertae Objects Beyond Redshift 1.3 - Uv-To-Nir Photometry And Photometric Redshift For Fermi/Lat Blazars, A. Rau, P. Schady, J. Greiner, M. Salvato, M. Ajello, E. Bottacini, N. Gehrels, P.M. J. Afonso, J. Elliott, R Filgas, D A. Kann, S Klose, T Krühler, M Nardini, A Nicuesa Guelbenzu, F Olivares E., A Rossi, V Sudilovsky, A C. Updike, Dieter H. Hartmann
Publications
Context.Observations of the γ -ray sky with Fermi led to significant advances towards understanding blazars, the most extreme classof Active Galactic Nuclei. A large fraction of the population detected by Fermi is formed by BL Lacertae (BL Lac) objects, whosesample has always suff ered from a severe redshift incompleteness due to the quasi-featureless optical spectra.Aims.Our goal is to provide a significant increase of the number of confirmed high-redshift BL Lac objects contained in the 2 LACFermi/LAT cataloge.Methods.For 103 Fermi/LAT blazars, photometric redshifts using spectral energy distribution fitting have been obtained. The pho-tometry includes 13 broad-band filters from the far ultraviolet …
Aztec Half Square Degree Survey Of The Shades Fields - Ii. Identifications, Redshifts, And Evidence For Large-Scale Structure, Michał J. Michałowski, J. S. Dunlop, R. J. Ivison, M. Cirasuolo, K. I. Caputi, I. Artexaga, V. Arumugam, J. E. Austermann, E. L. Chapin, S. C. Chapman, K. E. K. Coppin, E. Egami, D. H. Hughes, E. Ibar, A. M. J. Mortier, A. M. Schael, K. S. Scott, I. Smail, T. A. Targett, J. Wagg, Grant Wilson, L. Xu, M. Yun
Aztec Half Square Degree Survey Of The Shades Fields - Ii. Identifications, Redshifts, And Evidence For Large-Scale Structure, Michał J. Michałowski, J. S. Dunlop, R. J. Ivison, M. Cirasuolo, K. I. Caputi, I. Artexaga, V. Arumugam, J. E. Austermann, E. L. Chapin, S. C. Chapman, K. E. K. Coppin, E. Egami, D. H. Hughes, E. Ibar, A. M. J. Mortier, A. M. Schael, K. S. Scott, I. Smail, T. A. Targett, J. Wagg, Grant Wilson, L. Xu, M. Yun
Grant Wilson
The AzTEC 1.1 mm survey of the SCUBA HAlf Degree Extragalactic Survey (SHADES) fields is the largest (0.7 deg2) blank-field millimetre-wavelength survey undertaken to date at a resolution of ~18" and a depth of ~1 mJy. We have used the deep optical-to-radio multi-wavelength data in the SHADES Lockman Hole East and SXDF/UDS fields to obtain galaxy identifications for ~64% (~80% with tentative identifications) of the 148 AzTEC-SHADES 1.1 mm sources, exploiting deep radio and 24 um data complemented by methods based on 8 um flux-density and red optical-infrared (i-K) colour. This unusually high identification rate can be attributed to the …
Bl Lacertae Objects Beyond Redshift 1.3 – Uv-To-Nir Photometry And Photometric Redshift For Fermi/Lat Blazars, A. Rau, P. Schady, J. Greiner, M. Salvato, M. Ajello, E. Bottacini, N. Gehrels, P.M.J. Afonso, J. Elliott, R. Filgas, D.A. Kann, S. Klose, T. Krühler, M. Nardini, A. Nicuesa Guelbenzu, F. Olivares E., A. Rossi, V. Sudilovsky, Adria Updike, D.H. Hartmann
Bl Lacertae Objects Beyond Redshift 1.3 – Uv-To-Nir Photometry And Photometric Redshift For Fermi/Lat Blazars, A. Rau, P. Schady, J. Greiner, M. Salvato, M. Ajello, E. Bottacini, N. Gehrels, P.M.J. Afonso, J. Elliott, R. Filgas, D.A. Kann, S. Klose, T. Krühler, M. Nardini, A. Nicuesa Guelbenzu, F. Olivares E., A. Rossi, V. Sudilovsky, Adria Updike, D.H. Hartmann
Arts & Sciences Faculty Publications
Context. Observations of the γ-ray sky with Fermi led to significant advances towards understanding blazars, the most extreme class of active galactic nuclei. A large fraction of the population detected by Fermi is formed by BL Lacertae (BL Lac) objects, whose sample has always suffered from a severe redshift incompleteness due to the quasi-featureless optical spectra. Aims. Our goal is to provide a significant increase of the number of confirmed high-redshift BL Lac objects contained in the 2 LAC Fermi/LAT cataloge.Methods. For 103 Fermi/LAT blazars, photometric redshifts using spectral energy distribution fitting have been obtained.The photometry includes 13 broad-band filters …
The Ghosts Survey. I. Hubble Space Telescope Advanced Camera For Surveys Data., D. J. Radburn-Smith, R. S. De Jong, A. C. Seth, J. Bailin, E. F. Bell, T. M. Brown, J. S. Bullock, S. Courteau, J. J. Dalcanton, H. C. Ferguson, P. Goudfrooij, S. Holfeltz, Benne W. Holwerda, C. Purcell, J. Sick, D. Streich, M. Vlajic, D. B. Zucker
The Ghosts Survey. I. Hubble Space Telescope Advanced Camera For Surveys Data., D. J. Radburn-Smith, R. S. De Jong, A. C. Seth, J. Bailin, E. F. Bell, T. M. Brown, J. S. Bullock, S. Courteau, J. J. Dalcanton, H. C. Ferguson, P. Goudfrooij, S. Holfeltz, Benne W. Holwerda, C. Purcell, J. Sick, D. Streich, M. Vlajic, D. B. Zucker
Faculty Scholarship
We present an overview of the GHOSTS survey, the largest study to date of the resolved stellar populations in the outskirts of disk galaxies. The sample consists of 14 disk galaxies within 17 Mpc, whose outer disks and halos are imaged with the Hubble Space Telescope Advanced Camera for Surveys (ACS). In the first paper of this series, we describe the sample, explore the benefits of using resolved stellar populations, and discuss our ACS F606W and F814W photometry. We use artificial star tests to assess completeness and use overlapping regions to estimate photometric uncertainties. The median depth of the survey …
On The Detection Of Ionizing Radiation Arising From Star-Forming Galaxies At Redshift Z ~ 3-4 : Looking For Analogs Of "Stellar Reionizers", Eros Vanzella, Yicheng Guo, Mauro Giavalisco, Andrea Grazian, Marco Castellano, Stefano Cristiani, Mark Dickinson, Adriano Fontana, Mario Nonino, Emanuele Giallongo, Laura Pentericci, Audrey Galametz, S. M. Faber, Henry C. Ferguson, Norman A. Grogin, Anton M. Koekemoer, Jeffrey Newman, Brian D. Siana
On The Detection Of Ionizing Radiation Arising From Star-Forming Galaxies At Redshift Z ~ 3-4 : Looking For Analogs Of "Stellar Reionizers", Eros Vanzella, Yicheng Guo, Mauro Giavalisco, Andrea Grazian, Marco Castellano, Stefano Cristiani, Mark Dickinson, Adriano Fontana, Mario Nonino, Emanuele Giallongo, Laura Pentericci, Audrey Galametz, S. M. Faber, Henry C. Ferguson, Norman A. Grogin, Anton M. Koekemoer, Jeffrey Newman, Brian D. Siana
Mauro Giavalisco
We use the spatially-resolved, multi-band photometry in the GOODS South field acquired by the CANDELS project to constrain the nature of candidate Lyman continuum (LyC) emitters at redshift z~3.7 identified using ultra-deep imaging below the Lyman limit (1-sigma limit of ~30 AB in a 2" diameter aperture). In 18 candidates, out of a sample of 19 with flux detected at >3-sigma level, the light centroid of the candidate LyC emission is offset from that of the LBG by up to 1.5". We fit the SED of the LyC candidates to spectral population synthesis models to measure photometric redshifts and the …
A Detailed Study Of Photometric Redshifts For Goods-South Galaxies, Tomas Dahlen, Bahram Mobasher, Mark Dickinson, Henry C. Ferguson, Mauro Giavalisco, Norman A. Grogin, Yicheng Guo, Anton Koekemoer, Kyoung-Soo Lee, Seong-Kook Lee, Mario Nonino, Adam G. Reiss, Sara Salimbeni
A Detailed Study Of Photometric Redshifts For Goods-South Galaxies, Tomas Dahlen, Bahram Mobasher, Mark Dickinson, Henry C. Ferguson, Mauro Giavalisco, Norman A. Grogin, Yicheng Guo, Anton Koekemoer, Kyoung-Soo Lee, Seong-Kook Lee, Mario Nonino, Adam G. Reiss, Sara Salimbeni
Mauro Giavalisco
We use the deepest and the most comprehensive photometric data currently available for GOODS-South galaxies to measure their photometric redshifts. The photometry includes VLT/VIMOS (U-band), HST/ACS (F435W, F606W, F775W, and F850LP bands), VLT/ISAAC (J-, H-, and Ks-bands), and four Spitzer/IRAC channels (3.6, 4.5, 5.8, and 8.0 micron). The catalog is selected in the z-band (F850LP) and photometry in each band is carried out using the recently completed TFIT algorithm, which performs PSF matched photometry uniformly across different instruments and filters, despite large variations in PSFs and pixel scales. Photometric redshifts are derived using the GOODZ code, which is based on …
Spectroscopic Confirmation Of Z~7 Lbgs: Probing The Earliest Galaxies And The Epoch Of Reionization, L. Pentericci, A. Fontana, E. Vanzella, M. Castellano, A. Grazian, M. Dijkstra, K. Boustia, S. Cristiani, M. Dickinson, E. Giallongo, Mauro Giavalisco, R. Maiolino, A. Moorwood, P. Santini
Spectroscopic Confirmation Of Z~7 Lbgs: Probing The Earliest Galaxies And The Epoch Of Reionization, L. Pentericci, A. Fontana, E. Vanzella, M. Castellano, A. Grazian, M. Dijkstra, K. Boustia, S. Cristiani, M. Dickinson, E. Giallongo, Mauro Giavalisco, R. Maiolino, A. Moorwood, P. Santini
Mauro Giavalisco
We present the final results from our ultra-deep spectroscopic campaign with FORS2 at the ESO/VLT for the confirmation of z~7 "z--band dropout" candidates selected from our VLT/Hawk-I imaging survey over three independent fields. In particular we report on two newly discovered galaxies at redshift ~6.7 in the NTT deep field: both galaxies show a Ly-alpha emission line with rest-frame EWs of the order 15-20 A and luminosities of 2-4 X 10^{42} erg/s. We also present the results of ultra-deep observations of a sample of i-dropout galaxies, from which we set a solid upper limit on the fraction of interlopers. Out …
The Lack Of Intense Lyman~Alpha In Ultradeep Spectra Of Z=7 Candidates In Goods-S: Imprint Of Reionization?, A. Fontana, E. Vanzella, L. Pentericci, M. Castellano, Mauro Giavalisco, A. Grazian, K. Boutsia, S. Christiani, M. Dickinson, E. Giallongo, M. Maiolino, A. Moorwood, P. Santini
The Lack Of Intense Lyman~Alpha In Ultradeep Spectra Of Z=7 Candidates In Goods-S: Imprint Of Reionization?, A. Fontana, E. Vanzella, L. Pentericci, M. Castellano, Mauro Giavalisco, A. Grazian, K. Boutsia, S. Christiani, M. Dickinson, E. Giallongo, M. Maiolino, A. Moorwood, P. Santini
Mauro Giavalisco
We present ultradeep optical spectroscopy obtained with FORS2 on VLT of seven Lyman-break galaxy (LBG) candidates at z>6.5 selected in the GOODS-S field from Hawk-I/VLT and WFC3/HST imaging. For one galaxy we detect a low significance emission line (S/N< 7), located at 9691.5 +/- 0.5A and with flux 3.4 x 10^(-18)erg/cm^2/s. If identified as Lyman alpha, it places the LBG at redshift z=6.972+/- 0.002, with a rest-frame equivalent width EW}=13A. Using Monte Carlo simulations and conservative EW distribution functions at 210 is ~ 2%, and that of observing only one galaxy out of seven with S/N=5 is ~4%, but these can be as small as ~1E-3, depending on the details of the EW distribution. We conclude that either a significant fraction of the candidates is not at high redshift or that some physical mechanism quenches the Lyman alpha emission emerging from the galaxies at z>6.5, abruptly reversing the trend of the increasing fraction of strong emitters with increasing redshift observed up to z~ 6.5. We discuss the possibility that an increasingly neutral intergalactic medium is responsible for such quenching.
Spectroscopic Confirmation Of Two Lyman Break Galaxies At Redshift Beyond 7, E. Vanzella, L. Pentericci, A. Fontana, A. Grazian, M. Castellano, K. Boutsia, S. Cristiani, M. Dickinson, S. Gallozzi, E. Giallongo, Mauro Giavalisco, R. Maiolino, A. Moorwood, D. Paris, P. Santini
Spectroscopic Confirmation Of Two Lyman Break Galaxies At Redshift Beyond 7, E. Vanzella, L. Pentericci, A. Fontana, A. Grazian, M. Castellano, K. Boutsia, S. Cristiani, M. Dickinson, S. Gallozzi, E. Giallongo, Mauro Giavalisco, R. Maiolino, A. Moorwood, D. Paris, P. Santini
Mauro Giavalisco
We report the spectroscopic confirmation of two Lyman break galaxies at redshift > 7. The galaxies were observed as part of an ultra-deep spectroscopic campaign with FORS2 at the ESO/VLT for the confirmation of z~7 ``z--band dropout'' candidates selected from our VLT/Hawk-I imaging survey. Both galaxies show a prominent emission line at 9735A and 9858A respectively: the lines have fluxes of ~ 1.6-1.2 x 10^(-17) erg/s/cm2 and exhibit a sharp decline on the blue side and a tail on the red side. The asymmetry is quantitatively comparable to the observed asymmetry in z ~ 6 Ly-alpha lines, where absorption by neutral …