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Full-Text Articles in Physical Sciences and Mathematics

Cosmology-Independent Estimate Of The Fraction Of Baryon Mass In The Igm From Fast Radio Burst Observations, Zhengxiang Li, He Gao, Jun-Jie Wei, Yuan-Pei Yang, Bing Zhang, Zong-Hong Zhu May 2019

Cosmology-Independent Estimate Of The Fraction Of Baryon Mass In The Igm From Fast Radio Burst Observations, Zhengxiang Li, He Gao, Jun-Jie Wei, Yuan-Pei Yang, Bing Zhang, Zong-Hong Zhu

Physics & Astronomy Faculty Research

The excessive dispersion measure (DM) of fast radio bursts (FRBs) has been proposed to be a powerful tool to study intergalactic medium (IGM) and to perform cosmography. One issue is that the fraction of baryons in the IGM, f IGM, is not properly constrained. Here, we propose a method of estimating f IGM using a putative sample of FRBs with the measurements of both DM and luminosity distance d L. The latter can be obtained if the FRB is associated with a distance indicator (e.g., a gamma-ray burst or a gravitational-wave event), or the redshift z of the FRB is …


The Dependence Of Intrinsic Alignment Of Galaxies On Wavelength Using Kids And Gama, Christos Georgiou, Harry Johnston, Henk Hoekstra, Massimo Viola, Konrad Kuijken, Benjamin Joachimi, Nora Elisa Chisari, Daniel J. Farrow, Hendrik Hildebrandt, Benne W. Holwerda, Arun Kannawadi Feb 2019

The Dependence Of Intrinsic Alignment Of Galaxies On Wavelength Using Kids And Gama, Christos Georgiou, Harry Johnston, Henk Hoekstra, Massimo Viola, Konrad Kuijken, Benjamin Joachimi, Nora Elisa Chisari, Daniel J. Farrow, Hendrik Hildebrandt, Benne W. Holwerda, Arun Kannawadi

Faculty Scholarship

The outer regions of galaxies are more susceptible to the tidal interactions that lead to intrinsic alignments of galaxies. The resulting alignment signal may therefore depend on the passband if the colours of galaxies vary spatially. To quantify this, we measured the shapes of galaxies with spectroscopic redshifts from the GAMA survey using deep gri imaging data from the KiloDegree Survey. The performance of the moment-based shape measurement algorithm DEIMOS was assessed using dedicated image simulations, which showed that the ellipticities could be determined with an accuracy better than 1% in all bands. Additional tests for potential systematic errors did …


Testing For Directionality In The Planck Polarization And Lensing Data, Majd Ghrear, Emory F. Bunn, Dagoberto Contreras, Douglas Scott Jan 2019

Testing For Directionality In The Planck Polarization And Lensing Data, Majd Ghrear, Emory F. Bunn, Dagoberto Contreras, Douglas Scott

Physics Faculty Publications

In order to better analyse the polarization of the cosmic microwave background (CMB), which is dominated by emission from our Galaxy, we need tools that can detect residual foregrounds in cleaned CMB maps. Galactic foregrounds introduce statistical anisotropy and directionality to the polarization pseudo-vectors of the CMB, which can be investigated by using the D statistic of Bunn and Scott. This statistic is rapidly computable and capable of investigating a broad range of data products for directionality. We demonstrate the application of this statistic to detecting foregrounds in polarization maps by analysing the uncleaned Planck 2018 frequency maps. For the …


The Dark Energy Survey Image Processing Pipeline, E. Morganson, R. A. Gruendl, F. Menanteau, M. Carrasco Kind, Y.-C. Chen, G. Daues, A. Drlica-Wagner, D. N. Friedel, M. Gower, M. W. G. Johnson, M. D. Johnson, R. Kessler, F. Paz-Chinchón, D. Petravick, C. Pond, B. Yanny, S. Allam, R. Armstrong, Wayne A. Barkhouse, K. Bechtol, A. Benoit-Lévy, G. M. Bernstein, E. Bertin, E. Buckley-Geer, R. Covarrubias, S. Desai, H. T. Diehl, D. A. Goldstein, D. Gruen, T. S. Li, H. Lin, J. Marriner, J. J. Mohr, E. Neilsen, C.-C. Ngeow, K. Paech, E. S. Rykoff, M. Sako, I. Sevilla-Noarbe, E. Sheldon, F. Sobreira, D. L. Tucker, W. Wester May 2018

The Dark Energy Survey Image Processing Pipeline, E. Morganson, R. A. Gruendl, F. Menanteau, M. Carrasco Kind, Y.-C. Chen, G. Daues, A. Drlica-Wagner, D. N. Friedel, M. Gower, M. W. G. Johnson, M. D. Johnson, R. Kessler, F. Paz-Chinchón, D. Petravick, C. Pond, B. Yanny, S. Allam, R. Armstrong, Wayne A. Barkhouse, K. Bechtol, A. Benoit-Lévy, G. M. Bernstein, E. Bertin, E. Buckley-Geer, R. Covarrubias, S. Desai, H. T. Diehl, D. A. Goldstein, D. Gruen, T. S. Li, H. Lin, J. Marriner, J. J. Mohr, E. Neilsen, C.-C. Ngeow, K. Paech, E. S. Rykoff, M. Sako, I. Sevilla-Noarbe, E. Sheldon, F. Sobreira, D. L. Tucker, W. Wester

Physics Faculty Publications

The Dark Energy Survey (DES) is a five-year optical imaging campaign with the goal of understanding the origin of cosmic acceleration. DES performs a ~5000 deg2 survey of the southern sky in five optical bands (g, r, i, z, Y) to a depth of ~24th magnitude. Contemporaneously, DES performs a deep, time-domain survey in four optical bands (g, r, i, z) over ~27 deg2. DES exposures are processed nightly with an evolving data reduction pipeline and evaluated for image quality to determine if they need to be retaken. Difference imaging and transient source detection are also …


The Sluggs Survey: Dark Matter Fractions At Large Radii And Assembly Epochs Of Early-Type Galaxies From Globular Cluster Kinematics, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader, Joachim Janz, Christopher Usher, Lee Spitler, Sabine Bellstedt, Anna Ferré-Mateu Jul 2017

The Sluggs Survey: Dark Matter Fractions At Large Radii And Assembly Epochs Of Early-Type Galaxies From Globular Cluster Kinematics, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader, Joachim Janz, Christopher Usher, Lee Spitler, Sabine Bellstedt, Anna Ferré-Mateu

Faculty Publications

We use globular cluster kinematics data, primarily from the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey, to measure the dark matter fraction (fDM) and the average dark matter density (〈ρDM〉) within the inner 5 effective radii (Re) for 32 nearby early-type galaxies (ETGs) with stellar mass log (M*/M⊙) ranging from 10.1 to 11.8. We compare our results with a simple galaxy model based on scaling relations as well as with cosmological hydrodynamical simulations where the dark matter profile has been modified through various physical processes. We find a high fDM (≥0.6) within 5 Re in most of our sample, …


Host Galaxy Extinction Of Type Ia Supernovae : Co-Evolution Of Interstellar Medium Structure And The Extinction Law With Star Formation., Benne W. Holwerda Mar 2017

Host Galaxy Extinction Of Type Ia Supernovae : Co-Evolution Of Interstellar Medium Structure And The Extinction Law With Star Formation., Benne W. Holwerda

Benne Holwerda

This paper presents a mechanism that may modify the extinction law for Type Ia supernovae (SNeIa) observed at higher redshift. Starting from the observations that (i) SNeIa occur predominantly in spiral galaxies, (ii) star formation ejects interstellar medium (ISM) out of the plane of spirals, (iii) star formation alters the extinction properties of the dust in the ISM, and (iv) there is substantially more star formation at higher redshift, I propose that spiral galaxies have a dustier halo in the past than they do now. The ejected material’s lower value of RV will lead to a lower average value (R¯ …


The Brightest Of Reionizing Galaxies Survey : Constraints On The Bright End Of The Z ~ 8 Luminosity Function., L. D. Bradley, M. Trenti, P. A. Oesch, M. Stiavelli, T. Treu, R. J. Bouwens, J. M. Shull, Benne W. Holwerda, N. Pirzkal Mar 2017

The Brightest Of Reionizing Galaxies Survey : Constraints On The Bright End Of The Z ~ 8 Luminosity Function., L. D. Bradley, M. Trenti, P. A. Oesch, M. Stiavelli, T. Treu, R. J. Bouwens, J. M. Shull, Benne W. Holwerda, N. Pirzkal

Benne Holwerda

We report the discovery of 33 Lyman-break galaxy candidates at z ∼ 8 detected in Hubble Space Telescope Wide Field Camera 3 (WFC3) imaging as part of the Brightest of Reionizing Galaxies (BoRG) pure-parallel survey. The ongoing BoRG survey currently has the largest area (274 arcmin2) with Y098 (or Y105), J125, and H160 band coverage needed to search for z ∼ 8 galaxies, about three times the current CANDELS area, and slightly larger than what will be the final CANDELS wide component with Y105 data (required to select z ∼ 8 sources). Our sample of 33 relatively bright Y098-dropout galaxies …


The Luminosity Function At Z ~ 8 From 97 Y-Band Dropouts : Inferences About Reionization., Kasper B. Schmidt, Tommaso Treu, Michele Trenti, Larry D. Bradley, Brandon C. Kelly, Pascal A. Oesch, Benne W. Holwerda, J. Michael Shull, Massimo Stiavelli Feb 2017

The Luminosity Function At Z ~ 8 From 97 Y-Band Dropouts : Inferences About Reionization., Kasper B. Schmidt, Tommaso Treu, Michele Trenti, Larry D. Bradley, Brandon C. Kelly, Pascal A. Oesch, Benne W. Holwerda, J. Michael Shull, Massimo Stiavelli

Benne Holwerda

We present the largest search to date for Y-band dropout galaxies (z ∼ 8 Lyman break galaxies, LBGs) based on 350 arcmin2 of Hubble Space Telescope observations in the V, Y, J, and H bands from the Brightest of Reionizing Galaxies (BoRG) survey. In addition to previously published data, the BoRG13 data set presented here includes approximately 50 arcmin2 of new data and deeper observations of two previous BoRG pointings, from which we present 9 new z ∼ 8 LBG candidates, bringing the total number of BoRG Y-band dropouts to 38 with 25.5 mJ 27.6 (AB system). We introduce a …


Galaxy And Mass Assembly (Gama) : Panchromatic Data Release (Far-Uv–Far-Ir) And The Low-Z Energy Budget., Simon P. Driver, Angus H. Wright, Stephen K. Andrews, Luke J. M. Davies, Prajwal R. Kafle, Rebecca Lange, Amanda J. Moffett, Elizabeth Mannering, Aaron S. G. Robotham, Kevin Vinsen, Mehmet Alpaslan, Ellen Andrae, Ivan K. Baldry, Amanda E. Bauer, Steven P. Bamford, Joss Bland-Hawthorn, Nathan Bourne, Sarah Brough, Michael J. I. Brown, Michelle Cluver, Scott M. Croom, Matthew Colless, Christopher J. Conselice, Elisabete Da Cunha, Roberto De Propris, Michael Drinkwater, Loretta Dunne, Steve Eales, Alastair Edge, Carlos Frenk, Alister W. Graham, Meiert Grootes, Benne W. Holwerda, Andrew M. Hopkins, Edo Ibar, Eelco Van Kampen, Lee S. Kelvin, Tom Jarrett, D. Heath Jones, Maritza A. Lara-Lopez, Jochen Liske, Angel R. Lopez-Sanchez, Jon Loveday, Steve J. Maddox, Barry Madore, Smriti Mahajan, Martin Meyer, Peder Norberg, Samantha J. Penny, Steven Phillipps, Cristina C. Popescu, Richard Tuffs, John A. Peacock, Kevin A. Pimbblet, Matthew Prescott, Kate Rowlands, Anne E. Sansom, Mark Seibert, Matthew W. L. Smith, Will J. Sutherland, Edward N. Taylor, Elisabetta Valiante, J. Antonio Vazquez-Mata, Lingyu Wang, Stephen M. Wilkins, Richard P. Williams Feb 2017

Galaxy And Mass Assembly (Gama) : Panchromatic Data Release (Far-Uv–Far-Ir) And The Low-Z Energy Budget., Simon P. Driver, Angus H. Wright, Stephen K. Andrews, Luke J. M. Davies, Prajwal R. Kafle, Rebecca Lange, Amanda J. Moffett, Elizabeth Mannering, Aaron S. G. Robotham, Kevin Vinsen, Mehmet Alpaslan, Ellen Andrae, Ivan K. Baldry, Amanda E. Bauer, Steven P. Bamford, Joss Bland-Hawthorn, Nathan Bourne, Sarah Brough, Michael J. I. Brown, Michelle Cluver, Scott M. Croom, Matthew Colless, Christopher J. Conselice, Elisabete Da Cunha, Roberto De Propris, Michael Drinkwater, Loretta Dunne, Steve Eales, Alastair Edge, Carlos Frenk, Alister W. Graham, Meiert Grootes, Benne W. Holwerda, Andrew M. Hopkins, Edo Ibar, Eelco Van Kampen, Lee S. Kelvin, Tom Jarrett, D. Heath Jones, Maritza A. Lara-Lopez, Jochen Liske, Angel R. Lopez-Sanchez, Jon Loveday, Steve J. Maddox, Barry Madore, Smriti Mahajan, Martin Meyer, Peder Norberg, Samantha J. Penny, Steven Phillipps, Cristina C. Popescu, Richard Tuffs, John A. Peacock, Kevin A. Pimbblet, Matthew Prescott, Kate Rowlands, Anne E. Sansom, Mark Seibert, Matthew W. L. Smith, Will J. Sutherland, Edward N. Taylor, Elisabetta Valiante, J. Antonio Vazquez-Mata, Lingyu Wang, Stephen M. Wilkins, Richard P. Williams

Benne Holwerda

We present the Galaxy And Mass Assembly (GAMA) Panchromatic Data Release (PDR) constituting over 230 deg2 of imaging with photometry in 21 bands extending from the far-UV to the far-IR. These data complement our spectroscopic campaign of over 300k galaxies, and are compiled from observations with a variety of facilities including: GALaxy Evolution eXplorer, Sloan Digital Sky Survey, Visible and Infrared Telescope for Astronomy (VISTA), Wide-field Infrared Survey Explorer, and Herschel, with the GAMA regions currently being surveyed by VLT Survey Telescope (VST) and scheduled for observations by Australian Square Kilometer Array Pathfinder (ASKAP). These data are processed to a …


Bright Galaxies At Hubble's Redshift Detection Frontier : Preliminary Results And Design From The Redshift Z ~ 9-10 Borg Pure-Parallel Hst Survey., V. Calvi, M. Trenti, M. Stiavelli, P. A. Oesch, L. Bradley, K. B. Schmidt, D. Coe, G. Brammer, S. Bernard, R. J. Bouwens, D. Carrasco, C. M. Carollo, Benne W. Holwerda, J. W. Mackenty, C. A. Mason, J. M. Shull, T. Treu Feb 2017

Bright Galaxies At Hubble's Redshift Detection Frontier : Preliminary Results And Design From The Redshift Z ~ 9-10 Borg Pure-Parallel Hst Survey., V. Calvi, M. Trenti, M. Stiavelli, P. A. Oesch, L. Bradley, K. B. Schmidt, D. Coe, G. Brammer, S. Bernard, R. J. Bouwens, D. Carrasco, C. M. Carollo, Benne W. Holwerda, J. W. Mackenty, C. A. Mason, J. M. Shull, T. Treu

Benne Holwerda

We present the first results and design from the redshift z ∼ 9–10 Brightest of the Reionizing Galaxies Hubble Space Telescope survey BoRG[z9–10], aimed at searching for intrinsically luminous unlensed galaxies during the first 700 Myr after the Big Bang. BoRG[z9–10] is the continuation of a multi-year pure-parallel near-IR and optical imaging campaign with the Wide Field Camera 3. The ongoing survey uses five filters, optimized for detecting the most distant objects and offering continuous wavelength coverage from λ = 0.35 μm to λ = 1.7 μm. We analyze the initial ∼130 arcmin2 of area over 28 independent lines of …


Hecs-Sz: The Hectospec Survey Of Sunyaev-Zeldovich-Selected Clusters, Kenneth J. Rines, Margaret J. Geller, Antonaldo Diaferio, Ho Seong Hwang Mar 2016

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) : Panchromatic Data Release (Far-Uv–Far-Ir) And The Low-Z Energy Budget., Simon P. Driver, Angus H. Wright, Stephen K. Andrews, Luke J. M. Davies, Prajwal R. Kafle, Rebecca Lange, Amanda J. Moffett, Elizabeth Mannering, Aaron S. G. Robotham, Kevin Vinsen, Mehmet Alpaslan, Ellen Andrae, Ivan K. Baldry, Amanda E. Bauer, Steven P. Bamford, Joss Bland-Hawthorn, Nathan Bourne, Sarah Brough, Michael J. I. Brown, Michelle Cluver, Scott M. Croom, Matthew Colless, Christopher J. Conselice, Elisabete Da Cunha, Roberto De Propris, Michael Drinkwater, Loretta Dunne, Steve Eales, Alastair Edge, Carlos Frenk, Alister W. Graham, Meiert Grootes, Benne W. Holwerda, Andrew M. Hopkins, Edo Ibar, Eelco Van Kampen, Lee S. Kelvin, Tom Jarrett, D. Heath Jones, Maritza A. Lara-Lopez, Jochen Liske, Angel R. Lopez-Sanchez, Jon Loveday, Steve J. Maddox, Barry Madore, Smriti Mahajan, Martin Meyer, Peder Norberg, Samantha J. Penny, Steven Phillipps, Cristina C. Popescu, Richard Tuffs, John A. Peacock, Kevin A. Pimbblet, Matthew Prescott, Kate Rowlands, Anne E. Sansom, Mark Seibert, Matthew W. L. Smith, Will J. Sutherland, Edward N. Taylor, Elisabetta Valiante, J. Antonio Vazquez-Mata, Lingyu Wang, Stephen M. Wilkins, Richard P. Williams Feb 2016

Galaxy And Mass Assembly (Gama) : Panchromatic Data Release (Far-Uv–Far-Ir) And The Low-Z Energy Budget., Simon P. Driver, Angus H. Wright, Stephen K. Andrews, Luke J. M. Davies, Prajwal R. Kafle, Rebecca Lange, Amanda J. Moffett, Elizabeth Mannering, Aaron S. G. Robotham, Kevin Vinsen, Mehmet Alpaslan, Ellen Andrae, Ivan K. Baldry, Amanda E. Bauer, Steven P. Bamford, Joss Bland-Hawthorn, Nathan Bourne, Sarah Brough, Michael J. I. Brown, Michelle Cluver, Scott M. Croom, Matthew Colless, Christopher J. Conselice, Elisabete Da Cunha, Roberto De Propris, Michael Drinkwater, Loretta Dunne, Steve Eales, Alastair Edge, Carlos Frenk, Alister W. Graham, Meiert Grootes, Benne W. Holwerda, Andrew M. Hopkins, Edo Ibar, Eelco Van Kampen, Lee S. Kelvin, Tom Jarrett, D. Heath Jones, Maritza A. Lara-Lopez, Jochen Liske, Angel R. Lopez-Sanchez, Jon Loveday, Steve J. Maddox, Barry Madore, Smriti Mahajan, Martin Meyer, Peder Norberg, Samantha J. Penny, Steven Phillipps, Cristina C. Popescu, Richard Tuffs, John A. Peacock, Kevin A. Pimbblet, Matthew Prescott, Kate Rowlands, Anne E. Sansom, Mark Seibert, Matthew W. L. Smith, Will J. Sutherland, Edward N. Taylor, Elisabetta Valiante, J. Antonio Vazquez-Mata, Lingyu Wang, Stephen M. Wilkins, Richard P. Williams

Faculty Scholarship

We present the Galaxy And Mass Assembly (GAMA) Panchromatic Data Release (PDR) constituting over 230 deg2 of imaging with photometry in 21 bands extending from the far-UV to the far-IR. These data complement our spectroscopic campaign of over 300k galaxies, and are compiled from observations with a variety of facilities including: GALaxy Evolution eXplorer, Sloan Digital Sky Survey, Visible and Infrared Telescope for Astronomy (VISTA), Wide-field Infrared Survey Explorer, and Herschel, with the GAMA regions currently being surveyed by VLT Survey Telescope (VST) and scheduled for observations by Australian Square Kilometer Array Pathfinder (ASKAP). These data are processed to a …


Bright Galaxies At Hubble's Redshift Detection Frontier : Preliminary Results And Design From The Redshift Z ~ 9-10 Borg Pure-Parallel Hst Survey., V. Calvi, M. Trenti, M. Stiavelli, P. A. Oesch, L. Bradley, K. B. Schmidt, D. Coe, G. Brammer, S. Bernard, R. J. Bouwens, D. Carrasco, C. M. Carollo, Benne W. Holwerda, J. W. Mackenty, C. A. Mason, J. M. Shull, T. Treu Jan 2016

Bright Galaxies At Hubble's Redshift Detection Frontier : Preliminary Results And Design From The Redshift Z ~ 9-10 Borg Pure-Parallel Hst Survey., V. Calvi, M. Trenti, M. Stiavelli, P. A. Oesch, L. Bradley, K. B. Schmidt, D. Coe, G. Brammer, S. Bernard, R. J. Bouwens, D. Carrasco, C. M. Carollo, Benne W. Holwerda, J. W. Mackenty, C. A. Mason, J. M. Shull, T. Treu

Faculty Scholarship

We present the first results and design from the redshift z ∼ 9–10 Brightest of the Reionizing Galaxies Hubble Space Telescope survey BoRG[z9–10], aimed at searching for intrinsically luminous unlensed galaxies during the first 700 Myr after the Big Bang. BoRG[z9–10] is the continuation of a multi-year pure-parallel near-IR and optical imaging campaign with the Wide Field Camera 3. The ongoing survey uses five filters, optimized for detecting the most distant objects and offering continuous wavelength coverage from λ = 0.35 μm to λ = 1.7 μm. We analyze the initial ∼130 arcmin2 of area over 28 independent lines of …


Comparing Dense Galaxy Cluster Redshift Surveys With Weak-Lensing Maps, Ho Seong Hwang, Margaret J. Geller, Antonaldo Diaferio, Kenneth J. Rines, J. Jabran Zahid Dec 2014

Comparing Dense Galaxy Cluster Redshift Surveys With Weak-Lensing Maps, Ho Seong Hwang, Margaret J. Geller, Antonaldo Diaferio, Kenneth J. Rines, J. Jabran Zahid

Physics & Astronomy

We use dense redshift surveys of nine galaxy clusters at z ~ 0.2 to compare the galaxy distribution in each system with the projected matter distribution from weak lensing. By combining 2087 new MMT/Hectospec redshifts and the data in the literature, we construct spectroscopic samples within the region of weak-lensing maps of high (70%-89%) and uniform completeness. With these dense redshift surveys, we construct galaxy number density maps using several galaxy subsamples. The shape of the main cluster concentration in the weak-lensing maps is similar to the global morphology of the number density maps based on cluster members alone, mainly …


The Luminosity Function At Z ~ 8 From 97 Y-Band Dropouts : Inferences About Reionization., Kasper B. Schmidt, Tommaso Treu, Michele Trenti, Larry D. Bradley, Brandon C. Kelly, Pascal A. Oesch, Benne W. Holwerda, J. Michael Shull, Massimo Stiavelli May 2014

The Luminosity Function At Z ~ 8 From 97 Y-Band Dropouts : Inferences About Reionization., Kasper B. Schmidt, Tommaso Treu, Michele Trenti, Larry D. Bradley, Brandon C. Kelly, Pascal A. Oesch, Benne W. Holwerda, J. Michael Shull, Massimo Stiavelli

Faculty Scholarship

We present the largest search to date for Y-band dropout galaxies (z ∼ 8 Lyman break galaxies, LBGs) based on 350 arcmin2 of Hubble Space Telescope observations in the V, Y, J, and H bands from the Brightest of Reionizing Galaxies (BoRG) survey. In addition to previously published data, the BoRG13 data set presented here includes approximately 50 arcmin2 of new data and deeper observations of two previous BoRG pointings, from which we present 9 new z ∼ 8 LBG candidates, bringing the total number of BoRG Y-band dropouts to 38 with 25.5 mJ 27.6 (AB system). We introduce a …


Properties Of Submillimeter Galaxies In The Candels Goods-South Field, Tommy Wiklind, Christopher J. Conselice, Thomas Dahlen, Mark E. Dickinson, Henry C. Ferguson, Norman A. Grogin, Yicheng Guo, Anton Koekemoer, Bahram Mobasher, Alice Mortlock, Adriano Fontana, Romeel Dave, Haojin Yan, Viviana Aequaviva, Matthew L.N. Ashby, Guillermo Barro, Karina L. Caputi, Marco Castellano, Avishai Dekel, Jennifer L. Donley, Giovanni G. Fazio, Mauro Giavalisco, Andrea Grazian, Nimish P. Hathi, Peter Kurezynski, Yu Lu, Elizabeth J. Mcgrath, Duilia F. De Mello, Michael Peth, Mohammed Sarafzedeh, Mauro Stefanon, Thomas Targett Feb 2014

Properties Of Submillimeter Galaxies In The Candels Goods-South Field, Tommy Wiklind, Christopher J. Conselice, Thomas Dahlen, Mark E. Dickinson, Henry C. Ferguson, Norman A. Grogin, Yicheng Guo, Anton Koekemoer, Bahram Mobasher, Alice Mortlock, Adriano Fontana, Romeel Dave, Haojin Yan, Viviana Aequaviva, Matthew L.N. Ashby, Guillermo Barro, Karina L. Caputi, Marco Castellano, Avishai Dekel, Jennifer L. Donley, Giovanni G. Fazio, Mauro Giavalisco, Andrea Grazian, Nimish P. Hathi, Peter Kurezynski, Yu Lu, Elizabeth J. Mcgrath, Duilia F. De Mello, Michael Peth, Mohammed Sarafzedeh, Mauro Stefanon, Thomas Targett

Mauro Giavalisco

We derive physical properties of 10 submillimeter galaxies located in the CANDELS coverage of the GOODS-South Field. The galaxies were first identified as sub- millimeter sources with the LABOCA bolometer and subsequently targeted for 870µm continuum observation with ALMA. The high angular resolution of the ALMA imaging allows secure counterparts to be identified in the CANDELS multiband dataset. The CANDELS data provide deep photometric data from UV through near-infrared wavelengths. Using synthetic spectral energy distributions, we derive photometric redshifts, stellar masses, extinction, ages, and the star formation history. The redshift range is z=1.65-4.76, with two of the galaxies located at …


Characterizing Faint Galaxies In The Reionization Epoch: Lbt Confirms Two L < 0.2l Sources At Z = 6.4 Behind The Clash/Frontier Fields Cluster Macs0717.5+3745, E. Vanzella, A. Fontana, A. Zitrin, E. Coe, L. Bradley, M. Postman, A. Grazian, M. Castellano, L. Pentericci, Mauro Giavalisco, P. Rosati, M. Nonino, R. Smit, L. Balestra, R. Bouwens, S. Cristiani, E. Giallongo, W. Zheng, L. Infante, F. Cusano, R. Speziali Jan 2014

Characterizing Faint Galaxies In The Reionization Epoch: Lbt Confirms Two L < 0.2l Sources At Z = 6.4 Behind The Clash/Frontier Fields Cluster Macs0717.5+3745, E. Vanzella, A. Fontana, A. Zitrin, E. Coe, L. Bradley, M. Postman, A. Grazian, M. Castellano, L. Pentericci, Mauro Giavalisco, P. Rosati, M. Nonino, R. Smit, L. Balestra, R. Bouwens, S. Cristiani, E. Giallongo, W. Zheng, L. Infante, F. Cusano, R. Speziali

Mauro Giavalisco

We report the LBT/MODS1 spectroscopic confirmation of two images of faint Lyman alpha emitters at z = 6.4 behind the Frontier Fields galaxy cluster MACSJ0717.5+3745. A wide range of lens models suggests that the two images are highly magnified, with a strong lower limit of μ > 5. These are the faintest z > 6 candidates spectroscopically confirmed to date. These may be also multiple images of the same z = 6.4 source as supported by their similar intrinsic properties, but the lens models are inconclusive regarding this interpretation. To be cautious, we derive the physical properties of each image individually. Thanks …


The Vimos Ultra-Deep Survey (Vuds): Fast Increase In The Fraction Of Strong Lyman-Α Emitters From Z=2 To Z=6, P. Cassata, L.A.M. Tasca, O. Le Fevre, C. Lemaux, B. Garilli, V. Le Brun, D. Maccagni, L. Pentericci, R. Thomas, E. Vanzella, G. Zamorani, E. Zucca, A. Amorin, S. Bardelli, P. Capak, L.P. Cassara, M. Castellano, A. Cimatti, J.G. Cuby, O. Cucciati, S. De La Torre, A. Durkalec, A. Fontana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, C. Moreau, S. Paltani, B. Ribeiro, M. Salvato, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, Y. Taniguchi, L. Tresse, D. Vergani, P.W. Wang, S. Charlot, T. Contini, S. Fotopoulou, C. Lopez-Sanjuan, Y. Mellier, N. Scoville Jan 2014

The Vimos Ultra-Deep Survey (Vuds): Fast Increase In The Fraction Of Strong Lyman-Α Emitters From Z=2 To Z=6, P. Cassata, L.A.M. Tasca, O. Le Fevre, C. Lemaux, B. Garilli, V. Le Brun, D. Maccagni, L. Pentericci, R. Thomas, E. Vanzella, G. Zamorani, E. Zucca, A. Amorin, S. Bardelli, P. Capak, L.P. Cassara, M. Castellano, A. Cimatti, J.G. Cuby, O. Cucciati, S. De La Torre, A. Durkalec, A. Fontana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, C. Moreau, S. Paltani, B. Ribeiro, M. Salvato, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, Y. Taniguchi, L. Tresse, D. Vergani, P.W. Wang, S. Charlot, T. Contini, S. Fotopoulou, C. Lopez-Sanjuan, Y. Mellier, N. Scoville

Mauro Giavalisco

Aims. The aim of this work is to constrain the evolution of the fraction of strong Lyα emitters among UV selected star-forming galaxies at 2 25 Å to increase from ~5% at z ~ 2 to ~30% at z ~ 6, with the increase being stronger beyond z ~ 4. We observe no difference, for the narrow range of UV luminosities explored in this work, between the fraction of strong Lyα emitters among galaxies fainter or brighter than M*FUV, although the fraction for the faint galaxies evolves faster, at 2


The Stellar Mass--Halo Mass Relation From Galaxy Clustering In Vuds: A High Star Formation Efficiency At Z≃3, A. Durkalec, O. Le Fevre, S. De La Torre, A. Pollo, P. Cassata, B. Garilli, V. Le Brun, B.C. Lemaux, D. Maccagni, L. Pentericci, L.A.M. Tasca, R. Thomas, E. Vanzella, G. Zamorani, E. Zucca, R. Amorin, S. Bardelli, L.P. Cassara, M. Castellano, A. Cimatti, O. Cucciati, A. Fontana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, S. Paltani, B. Ribeiro, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, L. Tresse, D. Vergani, P. Capak, S. Charlot, T. Contini, J.G. Cuby, J. Dunlop, S. Fotopoulou, A. Koekemoer, C. Lopez-Sanjuan, Y. Mellier, J. Pforr, M. Salvato, N. Scoville, Y. Taniguchi, P.W. Wang Jan 2014

The Stellar Mass--Halo Mass Relation From Galaxy Clustering In Vuds: A High Star Formation Efficiency At Z≃3, A. Durkalec, O. Le Fevre, S. De La Torre, A. Pollo, P. Cassata, B. Garilli, V. Le Brun, B.C. Lemaux, D. Maccagni, L. Pentericci, L.A.M. Tasca, R. Thomas, E. Vanzella, G. Zamorani, E. Zucca, R. Amorin, S. Bardelli, L.P. Cassara, M. Castellano, A. Cimatti, O. Cucciati, A. Fontana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, S. Paltani, B. Ribeiro, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, L. Tresse, D. Vergani, P. Capak, S. Charlot, T. Contini, J.G. Cuby, J. Dunlop, S. Fotopoulou, A. Koekemoer, C. Lopez-Sanjuan, Y. Mellier, J. Pforr, M. Salvato, N. Scoville, Y. Taniguchi, P.W. Wang

Mauro Giavalisco

The relation between the galaxy stellar mass M⋆ and the dark matter halo mass Mh gives important information on the efficiency in forming stars and assembling stellar mass in galaxies. We present measurements of the ratio of stellar mass to halo mass (SMHR) at redshifts 2 < z < 5, obtained from the VIMOS Ultra Deep Survey. We use halo occupation distribution (HOD) modelling of clustering measurements on ~3000 galaxies with spectroscopic redshifts to derive the dark matter halo mass Mh, and spectral energy density fitting over a large set of multi-wavelength data to derive the stellar mass M⋆ and compute the SMHR = M⋆/Mh. We find that the SMHR ranges from 1% to 2.5% for galaxies with M⋆ = 1.3 × 109 M⊙ to M⋆ = 7.4 × 109 M⊙ in DM halos with Mh = 1.3 × 1011 M⊙ to Mh = 3 × 1011 M⊙. We derive the integrated star formation efficiency (ISFE) of these galaxies and find that the star formation efficiency is a moderate 6−9% for lower mass galaxies, while it is relatively high at 16% for galaxies with the median stellar mass of the sample ~ 7 × 109 M⊙. The lower ISFE at lower masses may indicate that some efficient means of suppressing star formation is at work (like SNe feedback), while the high ISFE for the average galaxy at z ~ 3 indicates that these galaxies efficiently build up their stellar mass at a key epoch in the mass assembly process. Based on our results, we propose a possible scenario in which the average massive galaxy at z ~ 3 begins to experience truncation of its star formation within a few million years.


Discovery Of A Rich Proto-Cluster At Z=2.9 And Associated Diffuse Cold Gas In The Vimos Ultra-Deep Survey (Vuds), O. Cucciati, G. Zamoriani, B.C. Lemaux, S. Bardelli, A. Cimatti, O. Le Fevre, P. Cassata, B. Garilli, V. Le Brun, D. Maccagni, L. Pentericci, L.A.M. Tasca, R. Thomas, E. Vanzella, E. Zucca, R. Amorin, P. Capak, L. Cassara, M. Castellano, J.G. Cuby, S. De La Torre, A. Durkalec, A. Fontana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, C. Moreau, S. Paltani, B. Ribeiro, M. Salvato, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, Y. Taniguichi, L. Tresse, D. Vergani, P.W. Wang, S. Charlot, T. Contini, S. Fotopoulou, C. Lopez-Sanjuan, Y. Mellier, N. Scoville Jan 2014

Discovery Of A Rich Proto-Cluster At Z=2.9 And Associated Diffuse Cold Gas In The Vimos Ultra-Deep Survey (Vuds), O. Cucciati, G. Zamoriani, B.C. Lemaux, S. Bardelli, A. Cimatti, O. Le Fevre, P. Cassata, B. Garilli, V. Le Brun, D. Maccagni, L. Pentericci, L.A.M. Tasca, R. Thomas, E. Vanzella, E. Zucca, R. Amorin, P. Capak, L. Cassara, M. Castellano, J.G. Cuby, S. De La Torre, A. Durkalec, A. Fontana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, C. Moreau, S. Paltani, B. Ribeiro, M. Salvato, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, Y. Taniguichi, L. Tresse, D. Vergani, P.W. Wang, S. Charlot, T. Contini, S. Fotopoulou, C. Lopez-Sanjuan, Y. Mellier, N. Scoville

Mauro Giavalisco

No abstract provided.


The Vimos Ultra-Deep Survey (Vuds): Igm Transmission Towards Galaxies With 2.5, R. Thomas, O. Le Fevre, V. Le Brun, P. Cassata, B. Garilli, C. Lemaux, D. Maccagni, L. Pentericci, L.A.M. Tasca, G. Zamorani, R. Amorin, S. Bardelli, L. Cassara, M. Castellano, A. Cimatti, O. Cucciati, A. Durkalec, A. Fontana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, S. Paltani, B. Ribeiro, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, L. Tresse, E. Vanzella, D. Vergani, P. Capak, S. Charlot, T. Contini, J.G. Cuby, S. De La Torre, J. Dunlop, S. Fotopoulou, A. Koekemoer, C. Lopez-Sanjuan, Y. Mellier, J. Pforr, M. Salvato, N. Scoville, Y. Taniguchi, P.W. Wang Jan 2014

The Vimos Ultra-Deep Survey (Vuds): Igm Transmission Towards Galaxies With 2.5, R. Thomas, O. Le Fevre, V. Le Brun, P. Cassata, B. Garilli, C. Lemaux, D. Maccagni, L. Pentericci, L.A.M. Tasca, G. Zamorani, R. Amorin, S. Bardelli, L. Cassara, M. Castellano, A. Cimatti, O. Cucciati, A. Durkalec, A. Fontana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, S. Paltani, B. Ribeiro, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, L. Tresse, E. Vanzella, D. Vergani, P. Capak, S. Charlot, T. Contini, J.G. Cuby, S. De La Torre, J. Dunlop, S. Fotopoulou, A. Koekemoer, C. Lopez-Sanjuan, Y. Mellier, J. Pforr, M. Salvato, N. Scoville, Y. Taniguchi, P.W. Wang

Mauro Giavalisco

The observed UV rest-frame spectra of distant galaxies are the result of their intrinsic emission combined with absorption along the line of sight produced by the inter-galactic medium (IGM). Here we analyse the evolution of the mean IGM transmission Tr(Ly_alpha) and its dispersion along the line of sight for 2127 galaxies with 2.5= 4 compared to results from QSOs, but a degeneracy between dust extinction and IGM prevents to draw firm conclusions if the internal dust extinction for star-forming galaxies at z>4 takes a mean value significantly in excess of E(B-V)>0.15. Most importantly, we find a large dispersion …


The X-Ray Properties Of Optically Selected Clusters Of Galaxies, A. K. Hicks, G. W. Pratt, M. Donahue, E. Ellingson, M. Gladders, H. Böhringer, H. K. C. Yee, Renbin Yan, J. H. Croston, D. G. Gilbank May 2013

The X-Ray Properties Of Optically Selected Clusters Of Galaxies, A. K. Hicks, G. W. Pratt, M. Donahue, E. Ellingson, M. Gladders, H. Böhringer, H. K. C. Yee, Renbin Yan, J. H. Croston, D. G. Gilbank

Physics and Astronomy Faculty Publications

We present the results of Chandra and Suzaku X-ray observations of nine moderate-redshift (0.16 < z < 0.42) clusters discovered via the Red-sequence Cluster Survey (RCS). Surface brightness profiles are fitted to β-models, gas masses are determined, integrated spectra are extracted within R2500, and X-ray temperatures and luminosities are inferred. TheLXTX relationship expected from self-similar evolution is tested by comparing this sample to our previous X-ray investigation of nine high-redshift (0.6 < z < 1.0) optically selected clusters. We find that optically selected clusters are systematically less luminous than X-ray selected clusters of similar X-ray temperature at both moderate and high z. We are unable to constrain evolution in the LXTX relation with these data, but find it consistent with no evolution, within relatively large uncertainties. To investigate selection effects, we compare the X-ray properties of our sample to those of clusters in the …


Measuring The Ultimate Halo Mass Of Galaxy Clusters: Redshifts And Mass Profiles From The Hectospec Cluster Survey (Hecs), Kenneth J. Rines Apr 2013

Measuring The Ultimate Halo Mass Of Galaxy Clusters: Redshifts And Mass Profiles From The Hectospec Cluster Survey (Hecs), Kenneth J. Rines

Physics & Astronomy

The infall regions of galaxy clusters represent the largest gravitationally bound structures in a LambdaCDM universe. Measuring cluster mass profiles into the infall regions provides an estimate of the ultimate mass of these halos. We use the caustic technique to measure cluster mass profiles from galaxy redshifts obtained with the Hectospec Cluster Survey (HeCS), an extensive spectroscopic survey of galaxy clusters with MMT/Hectospec. We survey 58 clusters selected by X-ray flux at 0.1 < z < 0.3. The survey includes 22,680 unique MMT/Hectospec redshifts for individual galaxies; 10,145 of these galaxies are cluster members. For each cluster, we acquired high signal-to-noise spectra for ~200 cluster members and a comparable number of foreground/background galaxies. The cluster members trace out infall patterns around the clusters. The members define a very narrow red sequence. We demonstrate that the determination of velocity dispersion is insensitive to the inclusion of bluer members (a small fraction of the cluster population). We apply the caustic technique to define membership and estimate the mass profiles to large radii. The ultimate halo mass of clusters (the mass that remains bound in the far future of a LambdaCDM universe) is on average (1.99 ± 0.11)M 200, a new observational cosmological test in essential agreement with simulations. Summed profiles binned in M 200 and in LX demonstrate that the predicted Navarro-Frenk-White …


Measuring The Mass Distribution In Galaxy Clusters, Margaret J. Geller, Antonaldo Diaferio, Kenneth J. Rines, Ana Laura Serra Feb 2013

Measuring The Mass Distribution In Galaxy Clusters, Margaret J. Geller, Antonaldo Diaferio, Kenneth J. Rines, Ana Laura Serra

Physics & Astronomy

Cluster mass profiles are tests of models of structure formation. Only two current observational methods of determining the mass profile, gravitational lensing, and the caustic technique are independent of the assumption of dynamical equilibrium. Both techniques enable the determination of the extended mass profile at radii beyond the virial radius. For 19 clusters, we compare the mass profile based on the caustic technique with weak lensing measurements taken from the literature. This comparison offers a test of systematic issues in both techniques. Around the virial radius, the two methods of mass estimation agree to within ~30%, consistent with the expected …


The Brightest Of Reionizing Galaxies Survey : Constraints On The Bright End Of The Z ~ 8 Luminosity Function., L. D. Bradley, M. Trenti, P. A. Oesch, M. Stiavelli, T. Treu, R. J. Bouwens, J. M. Shull, Benne W. Holwerda, N. Pirzkal Dec 2012

The Brightest Of Reionizing Galaxies Survey : Constraints On The Bright End Of The Z ~ 8 Luminosity Function., L. D. Bradley, M. Trenti, P. A. Oesch, M. Stiavelli, T. Treu, R. J. Bouwens, J. M. Shull, Benne W. Holwerda, N. Pirzkal

Faculty Scholarship

We report the discovery of 33 Lyman-break galaxy candidates at z ∼ 8 detected in Hubble Space Telescope Wide Field Camera 3 (WFC3) imaging as part of the Brightest of Reionizing Galaxies (BoRG) pure-parallel survey. The ongoing BoRG survey currently has the largest area (274 arcmin2) with Y098 (or Y105), J125, and H160 band coverage needed to search for z ∼ 8 galaxies, about three times the current CANDELS area, and slightly larger than what will be the final CANDELS wide component with Y105 data (required to select z ∼ 8 sources). Our sample of 33 relatively bright Y098-dropout galaxies …


The Assembly Of Galaxies Over Cosmic Time, Yicheng Guo Sep 2012

The Assembly Of Galaxies Over Cosmic Time, Yicheng Guo

Open Access Dissertations

To Understand how galaxies were assembled across the cosmic time remains one of the most outstanding questions in astronomy. The core of this question is how today's Hubble Sequence, namely the differentiation of galaxy morphology and its correlation to galaxy physical properties, is formed. In this thesis, we investigate the origin of the Hubble Sequence through galaxies at z~2, an epoch when the cosmic star formation activity reaches its peak and the properties of galaxies undergo dramatic transitions. Galaxies at z~2 have two important features that are distinct from nearby galaxies: much higher frequency of clumpy morphology in star-forming systems, …


Evidence For Significant Growth In The Stellar Mass Of Brightest Cluster Galaxies Over The Past 10 Billion Years, C. Lidman, J. Suherli, A. Muzzin, Grant Wilson, R. Demarco, S. Brough, A. Rettura, J. Cox, A. Degroot, H. K. C. Yee, D. Gilbank, H. Hoekstra, M. Balogh, E. Ellingson, A. Hicks, J. Nantais, A. Noble, M. Lacy, J. Surace Jan 2012

Evidence For Significant Growth In The Stellar Mass Of Brightest Cluster Galaxies Over The Past 10 Billion Years, C. Lidman, J. Suherli, A. Muzzin, Grant Wilson, R. Demarco, S. Brough, A. Rettura, J. Cox, A. Degroot, H. K. C. Yee, D. Gilbank, H. Hoekstra, M. Balogh, E. Ellingson, A. Hicks, J. Nantais, A. Noble, M. Lacy, J. Surace

Grant Wilson

Using new and published data, we construct a sample of 160 brightest cluster galaxies (BCGs) spanning the redshift interval 0.03 < z < 1.63. We use this sample, which covers 70% of the history of the universe, to measure the growth in the stellar mass of BCGs after correcting for the correlation between the stellar mass of the BCG and the mass of the cluster in which it lives. We find that the stellar mass of BCGs increase by a factor of 1.8 between z=0.9 and z=0.2. Compared to earlier works, our result is closer to the predictions of semi-analytic models. However, BCGs at z=0.9, relative to BCGs at z=0.2, are still a factor of 1.5 more massive than the predictions of these models. Star formation rates in BCGs at z~1 are generally to low to result in significant amounts of mass. Instead, it is likely that most of the mass build up occurs through mainly dry mergers in which perhaps half of the mass is lost to the intra-cluster medium of the cluster.


The Vlt Lbg Redshift Survey I: Clustering And Dynamics Of ≈ 1000 Galaxies At Z ≈ 3⋆, R. M. Bielby, T. Shanks, P. M. Weilbacher, L. Infante, N. H.M. Crighton, C. Bornancini, N. Bouché, P. Héraudeau, D. G. Lambas, James D. Lowenthal, D. Minniti, N. Padilla, P. Petitjean, T. Theuns Jun 2011

The Vlt Lbg Redshift Survey I: Clustering And Dynamics Of ≈ 1000 Galaxies At Z ≈ 3⋆, R. M. Bielby, T. Shanks, P. M. Weilbacher, L. Infante, N. H.M. Crighton, C. Bornancini, N. Bouché, P. Héraudeau, D. G. Lambas, James D. Lowenthal, D. Minniti, N. Padilla, P. Petitjean, T. Theuns

Astronomy: Faculty Publications

We present the initial imaging and spectroscopic data acquired as part of the Very Large Telescope (VLT) VIMOS Lyman-break galaxy Survey. UBR (or UBVI) imaging covers five ≈36 × 36 arcmin fields centred on bright z > 3 quasi-stellar objects (QSOs), allowing ≈210002 < z < 3.5 galaxy candidates to be selected using the Lyman-break technique. We performed spectroscopic follow-up using VLT VIMOS, measuring redshifts for 1020 z > 2 Lyman-break galaxies and 10 z > 2 QSOs from a total of 19 VIMOS pointings. From the galaxy spectra, we observe a 625 ± 510kms velocity offset between the interstellar absorption and Lyman α emission-line redshifts, consistent with previous results. Using the photometric and spectroscopic catalogues, we have analysed the galaxy clustering at z≈ 3. The angular correlation …


Color And Stellar Population Gradients In Passively Evolving Galaxies At Z~2 From Hst/Wfc3 Deep Imaging In The Hubble Ultra Deep Field, Yicheng Guo, Mauro Giavalisco, Paolo Cassata, Henry C. Ferguson, Mark Dickinson, Alvio Renzini, Anton Koekemoer, Norman A. Grogin, Casey Papovich, Elena Tundo, Adriano Fontana, Jennifer M. Lotz, Sara Salimbeni Jan 2011

Color And Stellar Population Gradients In Passively Evolving Galaxies At Z~2 From Hst/Wfc3 Deep Imaging In The Hubble Ultra Deep Field, Yicheng Guo, Mauro Giavalisco, Paolo Cassata, Henry C. Ferguson, Mark Dickinson, Alvio Renzini, Anton Koekemoer, Norman A. Grogin, Casey Papovich, Elena Tundo, Adriano Fontana, Jennifer M. Lotz, Sara Salimbeni

Mauro Giavalisco

We report the detection of color gradients in six massive (stellar mass > 10^{10} M_{sun}) and passively evolving (specific SFR < 10^{-11}/yr) galaxies at redshift 1.3


Aztec 1.1 Mm Images Of 16 Radio Galaxies At 0.5, A. Humphrey, M. Zeballos, I. Aretxaga, D. H. Hughes, M. S. Yun, R. Cybulski, Grant Wilson, J. Austermann, H. Ezawa, R. Kawabe, K. Kohno, T. Perera, K. Scott, D. Sánchez-Arguelles, R. Gutermuth Jan 2011

Aztec 1.1 Mm Images Of 16 Radio Galaxies At 0.5, A. Humphrey, M. Zeballos, I. Aretxaga, D. H. Hughes, M. S. Yun, R. Cybulski, Grant Wilson, J. Austermann, H. Ezawa, R. Kawabe, K. Kohno, T. Perera, K. Scott, D. Sánchez-Arguelles, R. Gutermuth

Grant Wilson

We present 1.1 mm observations for a sample of 16 powerful radio galaxies at 0.5