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The Redshift Search Receiver Observations Of 12co J = 1 → 0 In 29 Ultraluminous Infrared Galaxies, Aeree Chung, Gopal Naraynan, Min S. Yun, Mark Heyer, Neal R. Erickson Jul 2009

The Redshift Search Receiver Observations Of 12co J = 1 → 0 In 29 Ultraluminous Infrared Galaxies, Aeree Chung, Gopal Naraynan, Min S. Yun, Mark Heyer, Neal R. Erickson

Neal Erickson

We present 12CO J=1-->0 observations of ultraluminous infrared galaxies (ULIRGs) obtained using the Redshift Search Receiver (RSR) on the 14-m telescope of the Five College Radio Astronomy Observatory. The RSR is a novel, dual-beam, dual-polarization receiver equipped with an ultra-wideband spectrometer backend that is being built as a facility receiver for the Large Millimeter Telescope. Our sample consists of 29 ULIRGs in the redshift range of 0.04-0.11, including 10 objects with no prior 12CO measurements. We have detected 27 systems (a detection rate of 93%), including 9 ULIRGs that are detected in CO for the first time. Our study …


Star Formation And Mass Assembly In High Redshift Galaxies, P. Santini, A. Fontana, A. Grazian, S. Salimbeni, F. Fiore, F. Fontanot, K. Boutsia, M. Castellano, S. Cristiani, C. De Santis, S. Gallozzi, E. Giallongo, N. Menci, M. Nonino, D. Paris, L. Pentericci, E. Vanzella Jul 2009

Star Formation And Mass Assembly In High Redshift Galaxies, P. Santini, A. Fontana, A. Grazian, S. Salimbeni, F. Fiore, F. Fontanot, K. Boutsia, M. Castellano, S. Cristiani, C. De Santis, S. Gallozzi, E. Giallongo, N. Menci, M. Nonino, D. Paris, L. Pentericci, E. Vanzella

Astronomy Department Faculty Publication Series

Aims. The goal of this work is to infer the star formation properties and the mass assembly process of high redshift (0.3 ≤ z < 2.5) galaxies from their IR emission using the 24 μm band of MIPS-Spitzer. Methods. We used an updated version of the GOODS-MUSIC catalog, which has multiwavelength coverage from 0.3 to 24 μm and either spectroscopic or accurate photometric redshifts.We describe how the catalog has been extended by the addition of mid-IR fluxes derived from theMIPS 24 μm image.We compared two different estimators of the star formation rate (SFR hereafter). One is the total infrared emission derived from 24 μm, estimated using both synthetic and empirical IR templates. The other one is a multiwavelength fit to the full galaxy SED, which automatically accounts for dust reddening and age–star formation activity degeneracies. For both estimates, we computed the SFR density and the specific SFR. Results. We show that the two SFR indicators are roughly consistent, once the uncertainties involved are taken into account. However, they show a systematic trend, IR-based estimates exceeding the fit-based ones as the star formation rate increases. With this new catalog, we show that: a) at z > 0.3, the star formation rate is correlated well with stellar mass, and this relationship seems to steepen with redshift if one relies on IR–based estimates of the SFR; b) the contribution to the global SFRD by massive galaxies increases with redshift up to ≃ 2.5, more rapidly than for galaxies of lower mass, but appears to flatten at higher z; c) despite this increase, the most important contributors to the SFRD at any z are galaxies …


Structural Properties Of Central Galaxies In Groups And Clusters, Yc Guo, Dh Mcintosh, Hj Mo, N Katz, Fc Van Den Bosch, M Weinberg, Sm Weinmann, A Pasquali, Xh Yang Jan 2009

Structural Properties Of Central Galaxies In Groups And Clusters, Yc Guo, Dh Mcintosh, Hj Mo, N Katz, Fc Van Den Bosch, M Weinberg, Sm Weinmann, A Pasquali, Xh Yang

Astronomy Department Faculty Publication Series

Using a statistically representative sample of 911 central galaxies (CENs) from the Sloan Digital Sky Survey (SDSS) Data Release 4 group catalogue, we study how the structure (shape and size) of the first rank (by stellar mass) group and cluster members depends on (1) galaxy stellar mass (Mstar), (2) the global environment defined by the dark matter halo mass (Mhalo) of the host group and (3) the local environment defined by their special halocentric position. We quantify the structure of SDSS galaxies with a galfit-based pipeline that fits two-dimensional Sérsic models to the r-band image data. Through tests with simulated …


Dust-Corrected Star Formation Rates Of Galaxies. I. Combinations Of H Alpha And Infrared Tracers, Rc Kennicutt, Cn Hao, D Calzetti, J Moustakas, Da Dale, G Bendo, Cw Engelbracht, Bd Johnson, Jc Lee Jan 2009

Dust-Corrected Star Formation Rates Of Galaxies. I. Combinations Of H Alpha And Infrared Tracers, Rc Kennicutt, Cn Hao, D Calzetti, J Moustakas, Da Dale, G Bendo, Cw Engelbracht, Bd Johnson, Jc Lee

Astronomy Department Faculty Publication Series

We combine Hα emission-line and infrared (IR) continuum measurements of two samples of nearby galaxies to derive dust attenuation-corrected star formation rates (SFRs). We use a simple energy balance based method that has been applied previously to H II regions in the Spitzer Infrared Nearby Galaxies Survey, and extend the methodology to integrated measurements of galaxies. We find that our composite Hα + IR based SFRs are in excellent agreement with attenuation-corrected SFRs derived from integrated spectrophotometry, over the full range of SFRs (0.01-80 M sun yr-1) and attenuations (0-2.5 mag) studied. We find that the combination of Hα and …


Hubble Space Telescope/Advanced Camera For Surveys Morphology Of Ly Alpha Emitters At Redshift 5.7 In The Cosmos Field, Y Taniguchi, Et. Al. Jan 2009

Hubble Space Telescope/Advanced Camera For Surveys Morphology Of Ly Alpha Emitters At Redshift 5.7 In The Cosmos Field, Y Taniguchi, Et. Al.

Astronomy Department Faculty Publication Series

We present detailed morphological properties of Lyα emitters (LAEs) at z ≈ 5.7 in the COSMOS field based on Hubble Space Telescope Advanced Camera for Surveys (ACS) data. The ACS imaging in the F814W filter covered 85 LAEs of the 119 LAEs identified in the full two square degree field, and 47 LAEs of them are detected in the ACS images. Nearly half of them are spatially extended with a size larger than 0.15 arcsec (∼0.88 kpc at z = 5.7) and up to 0.4 arcsec (∼2.5 kpc at z = 5.7). The others are nearly unresolved compact objects. Two …


Expanding The Search For Galaxies At Z Similar To 7-10 With New Nicmos Parallel Fields, Alaina L. Henry, Brian Siana, Matthew A. Malkan, Matthew L.N. Ashby, Carrie R. Bridge, Ranga-Ram Chary, James W. Colbert, Mauro Giavalisco, Harry I. Teplitz, Patrick J. Mccarthy Jan 2009

Expanding The Search For Galaxies At Z Similar To 7-10 With New Nicmos Parallel Fields, Alaina L. Henry, Brian Siana, Matthew A. Malkan, Matthew L.N. Ashby, Carrie R. Bridge, Ranga-Ram Chary, James W. Colbert, Mauro Giavalisco, Harry I. Teplitz, Patrick J. Mccarthy

Astronomy Department Faculty Publication Series

We have carried out a search for galaxies at z ∼ 7–10 in ∼14.4 arcmin2 of new NICMOS parallel imaging taken in the Great Observatories Origins Deep Survey (5.9 arcmin2), the Cosmic Origins Survey (7.2 arcmin2), and SSA22 (1.3 arcmin2). These images reach 5σ sensitivities of J110 = 26.0–27.5 (AB), and combined they increase the amount of deep near-infrared data by more than 60% in fields where the investment in deep optical data has already been made. We find no z > 7 candidates in our survey area, consistent with the Bouwens et al. measurements at z ∼ 7 and …


Biases And Uncertainties In Physical Parameter Estimates Of Lyman Break Galaxies From Broadband Photometry, Sk Lee, R Idzi, Hc Ferguson, Rs Somerville, T Wiklind, M Giavalisco Jan 2009

Biases And Uncertainties In Physical Parameter Estimates Of Lyman Break Galaxies From Broadband Photometry, Sk Lee, R Idzi, Hc Ferguson, Rs Somerville, T Wiklind, M Giavalisco

Astronomy Department Faculty Publication Series

We investigate the biases and uncertainties in estimates of physical parameters of high-redshift Lyman break galaxies (LBGs), such as stellar mass, mean stellar population age, and star formation rate (SFR), obtained from broadband photometry. These biases arise from the simplifying assumptions often used in fitting the spectral energy distributions (SEDs). By combining ΛCDM hierarchical structure formation theory, semianalytic treatments of baryonic physics, and stellar population synthesis models, we construct model galaxy catalogs from which we select LBGs at redshifts z ∼ 3.4, 4.0, and 5.0. The broadband photometric SEDs of these model LBGs are then analyzed by fitting galaxy template …


The Aztec/Sma Interferometric Imaging Survey Of Submillimeter-Selected High-Redshift Galaxies, Jd Younger, Gg Fazio, Js Huang, Min Yun, Gw Wilson, Mln Ashby, Ma Gurwell, Ab Peck, Gr Petitpas, Dj Wilner, Dh Hughes, I Aretxaga, S Kim, Ks Scott, J Austermann, T Perera, Jd Lowenthal Jan 2009

The Aztec/Sma Interferometric Imaging Survey Of Submillimeter-Selected High-Redshift Galaxies, Jd Younger, Gg Fazio, Js Huang, Min Yun, Gw Wilson, Mln Ashby, Ma Gurwell, Ab Peck, Gr Petitpas, Dj Wilner, Dh Hughes, I Aretxaga, S Kim, Ks Scott, J Austermann, T Perera, Jd Lowenthal

Astronomy Department Faculty Publication Series

We present results from a continuing interferometric survey of high-redshift submillimeter galaxies (SMGs) with the Submillimeter Array, including high-resolution (beam size ~2 arcsec) imaging of eight additional AzTEC 1.1 mm selected sources in the COSMOS field, for which we obtain six reliable (peak signal-to-noise ratio (S/N) >5 or peak S/N >4 with multiwavelength counterparts within the beam) and two moderate significance (peak S/N >4) detections. When combined with previous detections, this yields an unbiased sample of millimeter-selected SMGs with complete interferometric follow up. With this sample in hand, we (1) empirically confirm the radio-submillimeter association, (2) examine the submillimeter morphology—including …


The Relative Abundance Of Compact And Normal Massive Early-Type Galaxies And Its Evolution From Redshift Z~2 To The Present, P. Cassata, Mauro Giavalisco, Yicheng Guo, A. Renzini, H. Ferguson, A. M. Koekemoer, S. Salimbeni, C. Scarlata, N. A. Grogin, C. J. Conselice, T. Dahlen, J. M. Lotz, M. Dickinson, Lihwai Lin Jan 2009

The Relative Abundance Of Compact And Normal Massive Early-Type Galaxies And Its Evolution From Redshift Z~2 To The Present, P. Cassata, Mauro Giavalisco, Yicheng Guo, A. Renzini, H. Ferguson, A. M. Koekemoer, S. Salimbeni, C. Scarlata, N. A. Grogin, C. J. Conselice, T. Dahlen, J. M. Lotz, M. Dickinson, Lihwai Lin

Mauro Giavalisco

We report on the evolution of the number density and size of early-type galaxies from z~2 to z~0. We select a sample of 563 massive (M>10^{10} Msun), passively evolving (SSFR<10^{-2} Gyr^{-1}) and morphologically spheroidal galaxies at 01.2 and z<1.2, respectively). We measure a significant evolution of the mass-size relation of early-type galaxies, with the fractional increment that is almost independent on the stellar mass. Early-type galaxies (ETGs) formed at z>1 appear to be preferentially small, and the evolution of the mass-size relation at z<1 is driven by both the continuous size growth of the compact galaxies and the appearance of new ETGs with large sizes. We also find that the number density of all passive early-type galaxies increases rapidly, by a factor of 5, from z~2 to z~1, and then more mildly by another factor of 1.5 from z~1 to z~0. We interpret these results as the evidence that the bulk of the ETGs are formed at 1


Candels: The Contribution Of The Observed Galaxy Population To Cosmic Reionization, Steven L. Finkelstein, Casey Papovich, Russel E, Ryan Jr., Andreas H. Pawlik, Mark Dickinson, Henry C. Ferguson, Kristian Finlator, Anton M. Koekemoer, Mauro Giavalisco, Mauro Giavalisco, Asantha Cooray, James S. Dunlop, Sandy M. Faber, Norman A. Grogin, Dale D. Kocevski, Jeffrey A. Newman Jan 2009

Candels: The Contribution Of The Observed Galaxy Population To Cosmic Reionization, Steven L. Finkelstein, Casey Papovich, Russel E, Ryan Jr., Andreas H. Pawlik, Mark Dickinson, Henry C. Ferguson, Kristian Finlator, Anton M. Koekemoer, Mauro Giavalisco, Mauro Giavalisco, Asantha Cooray, James S. Dunlop, Sandy M. Faber, Norman A. Grogin, Dale D. Kocevski, Jeffrey A. Newman

Mauro Giavalisco

We present measurements of the specific ultraviolet luminosity density from a sample of 483 galaxies at 6 . z . 8. These galaxies were selected from new deep near-infrared Hubble Space Telescope imaging from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, Hubble UltraDeep Field 2009 and WFC3 Early Release Science programs. In contrast to the majority of previous analyses, which assume that the distribution of galaxy ultraviolet (UV) luminosities follows a Schechter distribution, and that the distribution continues to luminosities far below our observable limit, we investigate the contribution to reionization from galaxies which we can observe, free from …


Candels: Constraining The Agn-Merger Connection With Host Morphologies At Z~2, Dale D. Kocevski, S. M. Faber, Mark Mozena, Anton M. Koekemoer, Kirpal Nandra, Cyprian Rangel, Elise S. Laird, Marcella Brusa, Stijn Wuyts, Jonathan R. Trump, David C. Koo, Rachel S. Somerville, Eric F. Bell, Jennifer M. Lotz, David M. Alexander, Frederic Bournaud, Christopher J. Conselice, Tomas Dahlen, Avashi Dekel, Jennifer L. Donley, James S. Dunlop, Alexis Finoguenov, Antonis Georgakakis, Mauro Giavalisco, Yicheng Guo, Norman A. Grogin, Nimish P. Hathi, Stéphanie Juneau, Jeyhan S. Kartaltepe, Ray A. Lucas, Elizabeth J. Mcgrath, Daniel H. Mcintosh, Bahram Mobasher, Aday R. Robaina, David Rosario, Amber N. Straughn, Arjen Van Der Wel, Carolin Villforth Jan 2009

Candels: Constraining The Agn-Merger Connection With Host Morphologies At Z~2, Dale D. Kocevski, S. M. Faber, Mark Mozena, Anton M. Koekemoer, Kirpal Nandra, Cyprian Rangel, Elise S. Laird, Marcella Brusa, Stijn Wuyts, Jonathan R. Trump, David C. Koo, Rachel S. Somerville, Eric F. Bell, Jennifer M. Lotz, David M. Alexander, Frederic Bournaud, Christopher J. Conselice, Tomas Dahlen, Avashi Dekel, Jennifer L. Donley, James S. Dunlop, Alexis Finoguenov, Antonis Georgakakis, Mauro Giavalisco, Yicheng Guo, Norman A. Grogin, Nimish P. Hathi, Stéphanie Juneau, Jeyhan S. Kartaltepe, Ray A. Lucas, Elizabeth J. Mcgrath, Daniel H. Mcintosh, Bahram Mobasher, Aday R. Robaina, David Rosario, Amber N. Straughn, Arjen Van Der Wel, Carolin Villforth

Mauro Giavalisco

Using HST/WFC3 imaging taken as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), we examine the role that major galaxy mergers play in triggering active galactic nuclei (AGN) activity at z~2. Our sample consists of 72 moderate-luminosity (Lx ~ 1E42-1E44 erg/s) AGN at 1.5


The Redshift Search Receiver Observations Of 12co J = 1 → 0 In 29 Ultraluminous Infrared Galaxies, Aeree Chung, Gopal Narayanan, Min S. Yun, Mark Heyer, Neal R. Erickson Jan 2009

The Redshift Search Receiver Observations Of 12co J = 1 → 0 In 29 Ultraluminous Infrared Galaxies, Aeree Chung, Gopal Narayanan, Min S. Yun, Mark Heyer, Neal R. Erickson

Gopal Narayanan

We present 12CO J = 1 → 0 observations of ultraluminous infrared galaxies (ULIRGs) obtained using the Redshift Search Receiver (RSR) on the 14 m telescope of the Five College Radio Astronomy Observatory. The RSR is a novel, dual-beam, dual-polarization receiver equipped with an ultra-wideband spectrometer backend that is being built as a facility receiver for the Large Millimeter Telescope. Our sample consists of 29 ULIRGs in the redshift range of 0.04–0.11, including 10 objects with no prior 12CO measurements. We have detected 27 systems (a detection rate of 93%), including 9 ULIRGs that are detected in CO for the …


Expanding The Search For Galaxies At Z ~7-10 With New Nicmos Parallel Fields, Alaina L. Henry, Brian Siana, Matthew A. Malkan, Matthew L. N. Ashby, Carrie R. Bridge, Ranga-Ram Chary, James W. Colbert, Mauro Giavalisco, Harry I. Teplitz, Patrick J. Mccarthy Jan 2009

Expanding The Search For Galaxies At Z ~7-10 With New Nicmos Parallel Fields, Alaina L. Henry, Brian Siana, Matthew A. Malkan, Matthew L. N. Ashby, Carrie R. Bridge, Ranga-Ram Chary, James W. Colbert, Mauro Giavalisco, Harry I. Teplitz, Patrick J. Mccarthy

Mauro Giavalisco

We have carried out a search for galaxies at z ~ 7-10 in ~14.4 sq. arcmin of new NICMOS parallel imaging taken in the Great Observatories Origins Deep Survey (GOODS, 5.9 sq. arcmin), the Cosmic Origins Survey (COSMOS, 7.2 sq. arcmin), and SSA22 (1.3 sq. arcmin). These images reach 5 sigma sensitivities of J110 = 26.0-27.5 (AB), and combined they increase the amount of deep near-infrared data by more than 60% in fields where the investment in deep optical data has already been made. We find no z>7 candidates in our survey area, consistent with the Bouwens et al. …


Spectroscopic Observations Of Lyman-Break Galaxies At Redshift ~ 4, 5 And 6 In The Goods-South Field, E. Vanzella, Mauro Giavalisco, M. Dickinson, S. Cristiani, M. Nonino, H. Kuntschner, P. Popesso, P, Rosati, A. Renzini, D. Stern, C. Cesarsky, H. C. Ferguson, R. A. E. Fosbury, The Goods Team Jan 2009

Spectroscopic Observations Of Lyman-Break Galaxies At Redshift ~ 4, 5 And 6 In The Goods-South Field, E. Vanzella, Mauro Giavalisco, M. Dickinson, S. Cristiani, M. Nonino, H. Kuntschner, P. Popesso, P, Rosati, A. Renzini, D. Stern, C. Cesarsky, H. C. Ferguson, R. A. E. Fosbury, The Goods Team

Mauro Giavalisco

We report on observations of Lyman-break galaxies (LBGs) selected from the Great Observatories Origins Deep Survey at mean redshift z~4, 5 and 6, obtained with FORS2 spectrograph at the ESO-VLT.This program has yielded spectroscopic identifications for 114 galaxies of which 51 are at z~4, 31 at z~5, and 32 at z~6. The adopted selection criteria are effective, identifying galaxies at the expected redshift with minimal foreground contamination. Once selection effects are properly accounted for, the rest-frame UV spectra of the higher-redshift LBGs appear to be similar to their counterparts at z~3. As at z~3, LBGs at z~4 and z~5 show …


The Morphology Of Passively Evolving Galaxies At Z ~ 2 From Hst/Wfc3 Deep Imaging In The Hubble Ultradeep Field, P. Cassata, Mauro Giavalisco, Yicheng Guo, H. Ferguson, A. Koekemoer, A. Renzini, A. Fontana, S. Salimbeni, M. Dickinson, S. Casertano, C. J. Conselice, N. Grogin, J. M. Lotz, C. Papovich, R. A. Lucas, A. Straughn, Jonathan P. Gardner, L. Moustakas Jan 2009

The Morphology Of Passively Evolving Galaxies At Z ~ 2 From Hst/Wfc3 Deep Imaging In The Hubble Ultradeep Field, P. Cassata, Mauro Giavalisco, Yicheng Guo, H. Ferguson, A. Koekemoer, A. Renzini, A. Fontana, S. Salimbeni, M. Dickinson, S. Casertano, C. J. Conselice, N. Grogin, J. M. Lotz, C. Papovich, R. A. Lucas, A. Straughn, Jonathan P. Gardner, L. Moustakas

Mauro Giavalisco

We present near-IR images, obtained with the Hubble Space Telescope (HST) and the WFC3/IR camera, of six passive and massive galaxies at redshift 1.3


Photometric Properties Of Ly Alpha Emitters At Z=4.86 In The Cosmos 2 Square Degree Field, Y. Shioya, Y. Taniguchi, S. S. Sasaki, T. Nagao, T. Murayama, T. Saito, Y. Ideue, A. Nakajima, K. L. Matsuoka, J. Trump, N. Z. Scoville, D. B. Sanders, B. Mobasher, H. Aussel, P. Capak, J. Kartaltepe, A. Koekemoer, C. Carilli, R. S. Ellis, B. Garilli, Mauro Giavalisco, M. G. Kitzbichler, C. Impey, O. Lefevre, E. Schinnerer, V. Smolcic Jan 2009

Photometric Properties Of Ly Alpha Emitters At Z=4.86 In The Cosmos 2 Square Degree Field, Y. Shioya, Y. Taniguchi, S. S. Sasaki, T. Nagao, T. Murayama, T. Saito, Y. Ideue, A. Nakajima, K. L. Matsuoka, J. Trump, N. Z. Scoville, D. B. Sanders, B. Mobasher, H. Aussel, P. Capak, J. Kartaltepe, A. Koekemoer, C. Carilli, R. S. Ellis, B. Garilli, Mauro Giavalisco, M. G. Kitzbichler, C. Impey, O. Lefevre, E. Schinnerer, V. Smolcic

Mauro Giavalisco

We present results of a survey for Ly alpha emitters at z=4.86 based on optical narrowband (lambda_c=7126 angstrom, Delta lambda=73 angstrom) and broadband (B, V, r', i', and z') observations of the Cosmic Evolution Survey (COSMOS) field using Suprime-Cam on the Subaru Telescope. We find 79 LAE candidates at z=4.86 over a contiguous survey area of 1.83 deg^2, down to the Ly alpha line flux of 1.47 x 10^-17 ergs s^-1 cm^-2. We obtain the Ly alpha luminosity function with a best-fit Schechter parameters of log L^*=42.9^+0.5_-0.3 ergs s^-1 and phi^* = 1.2^+8.0_-1.1 x 10^-4 Mpc^-3 for alpha=-1.5 (fixed). The …


The Udf05 Follow-Up Of The Hubble Ultra Deep Field. Iii. The Luminosity Function At Z~6, Jian Su, Massimo Stiavelli, Pascal Oesch, Michele Trenti, Eddie Bergeron, Larry Bradley, Marcella Carollo, Tomas Dahlen, Henry C. Ferguson, Mauro Giavalisco, Anton Koekemoer, Simon Lilly, Ray A. Lucas, Bahram Mobasher, Nino Panagia, Cheryl Pavlovsky Jan 2009

The Udf05 Follow-Up Of The Hubble Ultra Deep Field. Iii. The Luminosity Function At Z~6, Jian Su, Massimo Stiavelli, Pascal Oesch, Michele Trenti, Eddie Bergeron, Larry Bradley, Marcella Carollo, Tomas Dahlen, Henry C. Ferguson, Mauro Giavalisco, Anton Koekemoer, Simon Lilly, Ray A. Lucas, Bahram Mobasher, Nino Panagia, Cheryl Pavlovsky

Mauro Giavalisco

In this paper, we present a derivation of the rest-frame 1400A luminosity function (LF) at redshift six from a new application of the maximum likelihood method by exploring the five deepest HST/ACS fields, i.e., the HUDF, two UDF05 fields, and two GOODS fields. We work on the latest improved data products, which makes our results more robust than those of previous studies. We use un-binned data and thereby make optimal use of the information contained in the dataset. We focus on the analysis to a magnitude limit where the completeness is larger than 50% to avoid possibly large errors in …


The Evolution Of The Galaxy Rest-Frame Ultraviolet Luminosity Function Over The First Two Billion Years, Steven L. Finkelstein, Russell E. Ryan Jr., Casey Papovich, Mark Dickinson, Mimi Song, Rachel Somerville, Herny C. Ferguson, Brett Salmon, Mauro Giavalisco, Anton M. Koekemoer, Matthew L. N. Ashby, Peter Behroozi, Marco Castellano, James S. Dunlop, Sandy M. Faber, Giovanni G. Fazio, Adriano Fontana, Norman A. Grogin, Nimish Hathi, Jason Jaacks, Dale D. Kocevski, Rachel Livermore, Ross J. Mclure, Emiliano Merlin, Bahram Mobasher, Jeffrey A. Newman, Marc Rafelski, Vithal Tilvi, S.P. Willner Jan 2009

The Evolution Of The Galaxy Rest-Frame Ultraviolet Luminosity Function Over The First Two Billion Years, Steven L. Finkelstein, Russell E. Ryan Jr., Casey Papovich, Mark Dickinson, Mimi Song, Rachel Somerville, Herny C. Ferguson, Brett Salmon, Mauro Giavalisco, Anton M. Koekemoer, Matthew L. N. Ashby, Peter Behroozi, Marco Castellano, James S. Dunlop, Sandy M. Faber, Giovanni G. Fazio, Adriano Fontana, Norman A. Grogin, Nimish Hathi, Jason Jaacks, Dale D. Kocevski, Rachel Livermore, Ross J. Mclure, Emiliano Merlin, Bahram Mobasher, Jeffrey A. Newman, Marc Rafelski, Vithal Tilvi, S.P. Willner

Mauro Giavalisco

No abstract provided.


Deep U Band And R Imaging Of Goods-South: Observations,Data Reduction And First Results, M. Nonino, M. Dickinson, P. Rosati, A. Grazian, N. Reddy, S. Cristiani, Mauro Giavalisco, H. Kuntschner, E. Vanzella, E. Daddi, C. Cesarsky Jan 2009

Deep U Band And R Imaging Of Goods-South: Observations,Data Reduction And First Results, M. Nonino, M. Dickinson, P. Rosati, A. Grazian, N. Reddy, S. Cristiani, Mauro Giavalisco, H. Kuntschner, E. Vanzella, E. Daddi, C. Cesarsky

Mauro Giavalisco

We present deep imaging in the {\em U} band covering an area of 630 arcmin$^{2}$ centered on the southern field of the Great Observatories Origins Deep Survey (GOODS). The data were obtained with the VIMOS instrument at the ESO Very Large Telescope. The final images reach a magnitude limit $U_{lim} \approx 29.8$ (AB, 1$\sigma$, in a 1\arcsec radius aperture), and have good image quality, with full width at half maximum $\approx 0.8\arcsec$. They are significantly deeper than previous U--band images available for the GOODS fields, and better match the sensitivity of other multi--wavelength GOODS photometry. The deeper U--band data yield …


Uv Continuum Slope And Dust Obscuration From Z~6 To Z~2: The Star Formation Rate Density At High Redshift, R. J. Bouwens, G. D. Illingworth, M. Franx, R.-R. Chary, G. R. Meurer, C. J. Conselice, H. Ford, Mauro Giavalisco, P. Van Dokkum Jan 2009

Uv Continuum Slope And Dust Obscuration From Z~6 To Z~2: The Star Formation Rate Density At High Redshift, R. J. Bouwens, G. D. Illingworth, M. Franx, R.-R. Chary, G. R. Meurer, C. J. Conselice, H. Ford, Mauro Giavalisco, P. Van Dokkum

Mauro Giavalisco

We provide a systematic measurement of the rest-frame UV continuum slope beta over a wide range in redshift (z~2-6) and rest-frame UV luminosity (0.1-2L*) to improve estimates of the SFR density at high redshift. We utilize the deep optical and infrared data (ACS/NICMOS) over the CDF-S and HDF-N GOODS fields, as well as the UDF for our primary UBVi "dropout" sample. We correct the observed distributions for selection biases and photometric scatter. We find that the UV-continuum slope of the most luminous galaxies is substantially redder at z~2-4 than it is at z~5-6. Lower luminosity galaxies are also found to …


The Unusual Niv]-Emitter Galaxy Gds J033218.92-275302.7: Star Formation Or Agn-Driven Winds From A Massive Galaxy At Z=5.56, E. Vanzella, A. Grazian, M. Hayes, L. Pentericci, D. Schaerer, M. Dickinson, S. Cristiani, Mauro Giavalisco, A. Verhamme, M. Nonino, P. Rosati Jan 2009

The Unusual Niv]-Emitter Galaxy Gds J033218.92-275302.7: Star Formation Or Agn-Driven Winds From A Massive Galaxy At Z=5.56, E. Vanzella, A. Grazian, M. Hayes, L. Pentericci, D. Schaerer, M. Dickinson, S. Cristiani, Mauro Giavalisco, A. Verhamme, M. Nonino, P. Rosati

Mauro Giavalisco

Aims: We investigate the nature of the source GDS J033218.92-275302.7at redshift ~ 5.56. Methods: The SED of the source is well sampled by 16 bands photometry, from UV-optical, near infrared and mid-infrared (MID-IR).The detection of signal in the MID-IR Spitzer/IRAC bands 5.8, 8.0 um -- where the nebular emission contribution is less effective -- suggests the presence of a Balmer break, signature of an underlying stellar population formed at earlier epochs. The optical spectrum shows a clear Lya emission line together with semi-forbidden NIV] 1483.3-1486.5 also in emission. Results: From the SED fitting and the Lya modelling it turns out …


Hst/Acs Morphology Of Lyman Alpha Emitters At Redshift 5.7 In The Cosmos Field, Y. Taniguchi, T. Murayama, N. Z. Scoville, S. S. Sasaki, T. Nagao, Y. Shioya, T. Saito, Y. Ideue, A. Nakajima, K. Matsuoka, D. B. Sanders, B. Mobasher, H. Aussel, P. Capak, M. Salvato, K. Koekemoer, C. Carilli, A. Cimatti, R. S. Ellis, B. Garilli, Mauro Giavalisco, O. Ilbert, C. D. Impey, M. G. Kitzbilcher, O. Le Fevre, H. J. Mccracken, C. Scarlata, E. Schinnerer, V. Smolcic, S. Tribiano, J. R. Trump Jan 2009

Hst/Acs Morphology Of Lyman Alpha Emitters At Redshift 5.7 In The Cosmos Field, Y. Taniguchi, T. Murayama, N. Z. Scoville, S. S. Sasaki, T. Nagao, Y. Shioya, T. Saito, Y. Ideue, A. Nakajima, K. Matsuoka, D. B. Sanders, B. Mobasher, H. Aussel, P. Capak, M. Salvato, K. Koekemoer, C. Carilli, A. Cimatti, R. S. Ellis, B. Garilli, Mauro Giavalisco, O. Ilbert, C. D. Impey, M. G. Kitzbilcher, O. Le Fevre, H. J. Mccracken, C. Scarlata, E. Schinnerer, V. Smolcic, S. Tribiano, J. R. Trump

Mauro Giavalisco

We present detailed morphological properties of Lyman alpha emitters (LAEs) at z~ 5.7 in the COSMOS field, based on {\it Hubble Space Telescope} Advanced Camera for Surveys (ACS) data. The ACS imaging in the F814W filter covered 85 LAEs of the 119 LAEs identified in the full two square degree field, and 47 LAEs of them are detected in the ACS images. Nearly half of them are spatially extended with a size larger than 0.15 arcsec (~0.88 kpc at z=5.7) up to 0.4 arcsec (~2.5 kpc at z=5.7). The others are nearly unresolved compact objects. Two LAEs show double-component structures, …


Evidence For A Fast Evolution Of The Uv Luminosity Function Beyond Redshift 6 From A Deep Hawk-I Survey Of The Goods-S Field, M. Castellano, A. Fontana, K. Boutsia, A. Grazian, L. Pentericci, R. Bouwens, M. Dickinson, Mauro Giavalisco, P. Santini, S. Cristiani, F. Fiore, S. Gallozzi, E. Giallongo, R. Maiolino, F. Mannucci, N. Menci, A. Moorwood, M. Nonino, D. Paris, A. Renzini, P. Rosati, S. Salimbeni, V. Testa, E. Vanzella Jan 2009

Evidence For A Fast Evolution Of The Uv Luminosity Function Beyond Redshift 6 From A Deep Hawk-I Survey Of The Goods-S Field, M. Castellano, A. Fontana, K. Boutsia, A. Grazian, L. Pentericci, R. Bouwens, M. Dickinson, Mauro Giavalisco, P. Santini, S. Cristiani, F. Fiore, S. Gallozzi, E. Giallongo, R. Maiolino, F. Mannucci, N. Menci, A. Moorwood, M. Nonino, D. Paris, A. Renzini, P. Rosati, S. Salimbeni, V. Testa, E. Vanzella

Mauro Giavalisco

We perform a deep search for galaxies in the redshift range 6.51, Y-J<1.5 and Y-K<2. The other public data in the UBVRIJHK bands are used to reject possible low redshift interlopers. The output has been compared with extensive Monte Carlo simulations to quantify the observational effects of our selection criteria as well as the effects of photometric errors. We detect 7 high quality candidates in the magnitude range Y=25.5-26.7. This interval samples the critical range for M* at z>6 (M_1500 ~- 19.5 to -21.5). After accounting for the expected incompleteness, we rule out at a 99% confidence level a Luminosity Function constant from z=6 to z=7, even including the effects of cosmic variance. For galaxies brighter than M_1500=-19.0 we derive a luminosity density rho_UV=1.5^{+2.0}_{-0.9} 10^25 erg/s/Hz/Mpc3, implying a decrease by a factor 3.5 from z=6 to z~6.8. On the basis of our findings, we make predictions for the surface densities expected in future surveys surveys, based on ULTRA-VISTA, HST-WFC3 or JWST-NIRCam, evaluating the best observational …


On The Stellar Populations And Evolution Of Star-Forming Galaxies At 6.3 < Z < 8.6, Steven L. Finkelstein, Casey Papovich, Mauro Giavalisco, Naveen A. Reddy, Henry C. Ferguson, Anton M. Koekemoer, Mark Dickinson Jan 2009

On The Stellar Populations And Evolution Of Star-Forming Galaxies At 6.3 < Z < 8.6, Steven L. Finkelstein, Casey Papovich, Mauro Giavalisco, Naveen A. Reddy, Henry C. Ferguson, Anton M. Koekemoer, Mark Dickinson

Mauro Giavalisco

We study the physical characteristics of galaxies at 6.3 < z < 8.6, selected from deep near-infrared imaging with the Wide Field Camera 3 (WFC3) on board the Hubble Space Telescope. Accounting for the photometric scatter using simulations, galaxies at z ~ 7 have bluer UV colors compared to typical local starburst galaxies at > 4 sigma confidence. Although these colors necessitate young ages (<100 Myr), low or zero dust attenuation, and low metallicities, these are explicable by normal (albeit unreddened) stellar populations, with no evidence for near-zero metallicities and/or top-heavy initial mass functions. The age of the Universe at these redshifts limits the amount of stellar mass in late-type populations, and the WFC3 photometry implies galaxy stellar masses ~ 10^8 - 10^9 Msol for Salpeter initial mass functions to a limiting magnitude of M_1500 ~ -18. The masses of ``characteristic'' (L*) z > 7 galaxies are smaller than those of L* Lyman break galaxies (LBGs) at lower redshifts, and are comparable to less evolved galaxies selected on the basis of their Lyman alpha emission at 3 < z < 6, implying that the 6.3 < z < 8.6 galaxies are the progenitors of more evolved galaxies at lower redshifts. We estimate that Lyman alpha emission is able to contribute to the observed WFC3 colors of galaxies at these redshifts, with an estimated typical line flux of ~ 10^-18 erg s^-1 cm^-2, roughly a factor of four below currently planned surveys. The integrated UV specific luminosity for the detected galaxies at z ~ 7 and z ~ 8 is within factors of a few of that required to reionize the IGM assuming low clumping factors, implying that in order to reionize the Universe galaxies at these redshifts have a high ( ~ 50%) escape fraction of Lyman continuum photons, possibly substantiated by the very blue colors of this population.


The Dynamics Of Satellite Disruption In Cold Dark Matter Haloes, Jh Choi, Md Weinberg, N Katz Jan 2009

The Dynamics Of Satellite Disruption In Cold Dark Matter Haloes, Jh Choi, Md Weinberg, N Katz

Astronomy Department Faculty Publication Series

We investigate the physical mechanisms of tidal heating and satellite disruption in cold dark matter host haloes using N-body simulations based on cosmological initial conditions. We show the importance of resonant shocks and resonant torques with the host halo to satellite heating. A resonant shock (torque) couples the radial (tangential) motion of a satellite in its orbit to its phase space. For a satellite on a circular orbit, an inner Lindblad resonance (ILR)-like resonance dominates the heating and this heating results in continuous satellite mass loss. We estimate the requirements for simulations to achieve these dynamics using perturbation theory. Both …


Comparison Of H Alpha And Uv Star Formation Rates In The Local Volume: Systematic Discrepancies For Dwarf Galaxies, Jc Lee, Ag De Paz, C Tremonti, Rc Kennicutt, S Salim, M Bothwell, D Calzetti, J Dalcanton, D Dale, C Engelbracht, Sjjg Funes, B Johnson, S Sakai, E Skillman, L Van Zee, F Walter, D Weisz Jan 2009

Comparison Of H Alpha And Uv Star Formation Rates In The Local Volume: Systematic Discrepancies For Dwarf Galaxies, Jc Lee, Ag De Paz, C Tremonti, Rc Kennicutt, S Salim, M Bothwell, D Calzetti, J Dalcanton, D Dale, C Engelbracht, Sjjg Funes, B Johnson, S Sakai, E Skillman, L Van Zee, F Walter, D Weisz

Astronomy Department Faculty Publication Series

Using a complete sample of ~300 star-forming galaxies within 11 Mpc of the Milky Way, we evaluate the consistency between star formation rates (SFRs) inferred from the far ultraviolet (FUV) non-ionizing continuum and Hα nebular emission, assuming standard conversion recipes in which the SFR scales linearly with luminosity at a given wavelength. Our analysis probes SFRs over 5 orders of magnitude, down to ultra-low activities on the order of ~10-4 M sun yr-1. The data are drawn from the 11 Mpc Hα and Ultraviolet Galaxy Survey (11HUGS), which has obtained Hα fluxes from ground-based narrowband imaging, and UV fluxes from …


The Chandra Cosmos Survey. I. Overview And Point Source Catalog, M Elvis, F Civano, C Vignali, S Puccetti, F Fiore, N Cappelluti, Tl Aldcroft, A Fruscione, G Zamorani, A Comastri, M Brusa, R Gilli, T Miyaji, F Damiani, Am Koekemoer, A Finoguenov, H Brunner, Cm Urry, J Silverman, V Mainieri, G Hasinger, R Griffiths, M Carollo, H Hao, L Guzzo, A Blain, D Calzetti, C Carilli, P Capak, S Ettori, G Fabbiano, C Impey, S Lilly, B Mobasher, M Rich, M Salvato, Db Sanders, E Schinnerer, N Scoville, P Shopbell, Je Taylor, Y Taniguchi, M Volonteri Jan 2009

The Chandra Cosmos Survey. I. Overview And Point Source Catalog, M Elvis, F Civano, C Vignali, S Puccetti, F Fiore, N Cappelluti, Tl Aldcroft, A Fruscione, G Zamorani, A Comastri, M Brusa, R Gilli, T Miyaji, F Damiani, Am Koekemoer, A Finoguenov, H Brunner, Cm Urry, J Silverman, V Mainieri, G Hasinger, R Griffiths, M Carollo, H Hao, L Guzzo, A Blain, D Calzetti, C Carilli, P Capak, S Ettori, G Fabbiano, C Impey, S Lilly, B Mobasher, M Rich, M Salvato, Db Sanders, E Schinnerer, N Scoville, P Shopbell, Je Taylor, Y Taniguchi, M Volonteri

Astronomy Department Faculty Publication Series

The Chandra COSMOS Survey (C-COSMOS) is a large, 1.8 Ms, Chandra program that has imaged the central 0.5 deg2 of the COSMOS field (centered at 10 h , +02 o ) with an effective exposure of ~160 ks, and an outer 0.4 deg2 area with an effective exposure of ~80 ks. The limiting source detection depths are 1.9 × 10–16 erg cm–2 s–1 in the soft (0.5-2 keV) band, 7.3 × 10–16 erg cm–2 s–1 in the hard (2-10 keV) band, and 5.7 × 10–16 erg cm–2 s–1 in the full (0.5-10 keV) band. Here we describe the strategy, design, …


Uv Continuum Slope And Dust Obscuration From Z Similar To 6 To Z Similar To 2: The Star Formation Rate Density At High Redshift, R. J. Bouwens, G. D. Illingworth, M. Franx, R.-R. Chary, G. R. Meurer, C. J. Conselice, H. Ford, M. Giavalisco, P. Van Dokkum Jan 2009

Uv Continuum Slope And Dust Obscuration From Z Similar To 6 To Z Similar To 2: The Star Formation Rate Density At High Redshift, R. J. Bouwens, G. D. Illingworth, M. Franx, R.-R. Chary, G. R. Meurer, C. J. Conselice, H. Ford, M. Giavalisco, P. Van Dokkum

Astronomy Department Faculty Publication Series

We provide a systematic measurement of the rest-frame UV continuum slope β over a wide range in redshift (z ∼ 2–6) and rest-frame UV luminosity (0.1 L*z = 3 to 2 L*z = 3) to improve estimates of the star formation rate (SFR) density at high redshift. We utilize the deep optical and infrared data (Advanced Camera for Surveys/NICMOS) over the Chandra Deep Field-South and Hubble Deep Field-North Great Observatories Origins Deep Survey fields, as well as the UDF for our primary UBVi "dropout" Lyman Break Galaxy sample. We also use strong lensing clusters to …


Deep U Band And R Imaging Of Goods-South: Observations, Data Reduction And First Results, M Nonino, M Dickinson, P Rosati, A Grazian, N Reddy, S Cristiani, M Giavalisco, H Kuntschner, E Vanzella, E Daddi, Rae Fosbury, C Cesarsky Jan 2009

Deep U Band And R Imaging Of Goods-South: Observations, Data Reduction And First Results, M Nonino, M Dickinson, P Rosati, A Grazian, N Reddy, S Cristiani, M Giavalisco, H Kuntschner, E Vanzella, E Daddi, Rae Fosbury, C Cesarsky

Astronomy Department Faculty Publication Series

We present deep imaging in the U band covering an area of 630 arcmin2 centered on the southern field of the Great Observatories Origins Deep Survey (GOODS). The data were obtained with the VIMOS instrument at the European Southern Observatory (ESO) Very Large Telescope. The final images reach a magnitude limit Ulim ≈ 29.8 (AB, 1σ, in a 1'' radius aperture), and have good image quality, with full width at half-maximum ≈08. They are significantly deeper than previous U-band images available for the GOODS fields, and better match the sensitivity of other multiwavelength GOODS photometry. The deeper U …


Spectroscopic Observations Of Lyman Break Galaxies At Redshifts Similar To 4, 5, And 6 In The Goods-South Field, E Vanzella, M Giavalisco, M Dickinson, S Cristiani, M Nonino, H Kuntschner, P Popesso, P Rosati, A Renzini, D Stern, C Cesarsky, Hc Ferguson, Rae Fosbury Jan 2009

Spectroscopic Observations Of Lyman Break Galaxies At Redshifts Similar To 4, 5, And 6 In The Goods-South Field, E Vanzella, M Giavalisco, M Dickinson, S Cristiani, M Nonino, H Kuntschner, P Popesso, P Rosati, A Renzini, D Stern, C Cesarsky, Hc Ferguson, Rae Fosbury

Astronomy Department Faculty Publication Series

We report on observations of Lyman-break galaxies (LBGs) selected from the Great Observatories Origins Deep Survey at mean redshift z~4, 5 and 6, obtained with FORS2 spectrograph at the ESO-VLT.This program has yielded spectroscopic identifications for 114 galaxies of which 51 are at z~4, 31 at z~5, and 32 at z~6. The adopted selection criteria are effective, identifying galaxies at the expected redshift with minimal foreground contamination. Once selection effects are properly accounted for, the rest-frame UV spectra of the higher-redshift LBGs appear to be similar to their counterparts at z~3. As at z~3, LBGs at z~4 and z~5 show …