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Full-Text Articles in Physical Sciences and Mathematics
Vimos Ultra-Deep Survey (Vuds): Witnessing The Assembly Of A Massive Cluster At Z~3.3, B.C. Lemaux, O. Cucciati, L.A.M. Tasca, O. Le Fevre, G. Zamorani, P. Cassata, B. Garilli, V. Le Brun, D. Maccagni, L. Pentericci, R. Thomas, E. Vanzella, E. Zucca, R. Amorin, S. Bardelli, P. Capak, L.P. Cassara, M. Castellano, A. Cimatti, 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. Taniguchi, L. Tresse, D. Vergani, P.W. Wang, S. Charlot, T. Contini, S. Fotopoulou, R.R. Gal, D.D. Kocevski, C. Lopez-Sanjuan, L.M. Lubin, Y. Mellier, T. Sadibekova, N. Scoville
Vimos Ultra-Deep Survey (Vuds): Witnessing The Assembly Of A Massive Cluster At Z~3.3, B.C. Lemaux, O. Cucciati, L.A.M. Tasca, O. Le Fevre, G. Zamorani, P. Cassata, B. Garilli, V. Le Brun, D. Maccagni, L. Pentericci, R. Thomas, E. Vanzella, E. Zucca, R. Amorin, S. Bardelli, P. Capak, L.P. Cassara, M. Castellano, A. Cimatti, 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. Taniguchi, L. Tresse, D. Vergani, P.W. Wang, S. Charlot, T. Contini, S. Fotopoulou, R.R. Gal, D.D. Kocevski, C. Lopez-Sanjuan, L.M. Lubin, Y. Mellier, T. Sadibekova, N. Scoville
Mauro Giavalisco
Using new spectroscopic observations obtained as part of the VIMOS Ultra-Deep Survey (VUDS), we performed a systematic search for overdense environments in the early universe (z> 2) and report here on the discovery of Cl J0227-0421, a massive protocluster at z = 3.29. This protocluster is characterized by both the large overdensity of spectroscopically confirmed members, δgal = 10.5 ± 2.8, and a significant overdensity in photometric redshift members. The halo mass of this protocluster is estimated by a variety of methods to be ~3 × 1014ℳ⊙ at z ~ 3.3, which, evolved to z = 0 results in a …
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 …
The Evolution Of Clustering Length, Large Scale Bias, And Host Halo Mass At 2, A. Durkalec, O. Le Fevre, A. Pollo, S. De La Torre, 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. Fonatana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, S. Paltani, B. Ribero, 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
The Evolution Of Clustering Length, Large Scale Bias, And Host Halo Mass At 2, A. Durkalec, O. Le Fevre, A. Pollo, S. De La Torre, 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. Fonatana, Mauro Giavalisco, A. Grazian, N.P. Hathi, O. Ilbert, S. Paltani, B. Ribero, 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
No abstract provided.
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
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.
The Mass Evolution Of The First Galaxies: Stellar Mass Functions And Star Formation Rates At 4 < Z < 7 In The Candels Goods-South Field, K. Duncan, C.J. Conselice, A. Mortlock, W.G. Hartley, Y. Guo, H.C. Ferguson, R. Dave, Y. Lu, J. Ownsworth, M.L.N. Ashby, A. Dekel, M. Dickinson, S. Faber, Mauro Giavalisco, N. Grogin, D. Kocevski, A. Koekemoer, R.S. Somerville, C.E. White
The Mass Evolution Of The First Galaxies: Stellar Mass Functions And Star Formation Rates At 4 < Z < 7 In The Candels Goods-South Field, K. Duncan, C.J. Conselice, A. Mortlock, W.G. Hartley, Y. Guo, H.C. Ferguson, R. Dave, Y. Lu, J. Ownsworth, M.L.N. Ashby, A. Dekel, M. Dickinson, S. Faber, Mauro Giavalisco, N. Grogin, D. Kocevski, A. Koekemoer, R.S. Somerville, C.E. White
Mauro Giavalisco
We measure new estimates for the galaxy stellar mass function and star formation rates for samples of galaxies at z ~ 4; 5; 6 & 7 using data in the CANDELS GOODS South-field. The deep near-infrared observations allow us to construct the stellar mass function at z > 6 directly for the first time. We estimate stellar masses for our sample by fitting the observed spectral energy distributions with synthetic stellar populations, including nebular line and continuum emission. The observed UV luminosity functions for the samples are consistent with previous observations, however we find that the observed MUV - M_ relation …
Stellar Masses From The Candels Survey: The Goods-South And Uds Field, P. Satini, H.C. Ferguson, A Fontana, B. Mobasher, G. Barro, M. Castellano, S.L. Finkelstein, A. Grazian, L.T. Hsu, B. Lee, S.K. Lee, J. Pforr, M. Salvato, T. Wiklind, S. Wuyts, O. Almaini, M.C. Cooper, A. Galametz, B. Weiner, R. Amorin, K. Boutsia, C.J. Conselice, T. Dahlen, M.C. Cooper, Mauro Giavalisco, N.A. Grogin, Y. Guo, N.P. Hathi, D. Kocevski, A.M. Koekemoer, P. Kurczynski, E. Merlin, A. Mortlock, J.A. Newman, D. Paris, L. Pentericci, R. Simons, S.P. Willner
Stellar Masses From The Candels Survey: The Goods-South And Uds Field, P. Satini, H.C. Ferguson, A Fontana, B. Mobasher, G. Barro, M. Castellano, S.L. Finkelstein, A. Grazian, L.T. Hsu, B. Lee, S.K. Lee, J. Pforr, M. Salvato, T. Wiklind, S. Wuyts, O. Almaini, M.C. Cooper, A. Galametz, B. Weiner, R. Amorin, K. Boutsia, C.J. Conselice, T. Dahlen, M.C. Cooper, Mauro Giavalisco, N.A. Grogin, Y. Guo, N.P. Hathi, D. Kocevski, A.M. Koekemoer, P. Kurczynski, E. Merlin, A. Mortlock, J.A. Newman, D. Paris, L. Pentericci, R. Simons, S.P. Willner
Mauro Giavalisco
We present the public release of the stellar mass catalogs for the GOODS-S and UDS fields obtained using some of the deepest near-IR images available, achieved as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) project. We combine the effort from ten different teams, who computed the stellar masses using the same photometry and the same redshifts. Each team adopted their preferred fitting code, assumptions, priors, and parameter grid. The com- bination of results using the same underlying stellar isochrones reduces the systematics associated with the fitting code and other choices. Thanks to the availability of different …
The Source Counts Of Submillimetre Galaxies Detected At 1.1 Mm, K. S. Scott, Grant W. Wilson, I. Aretxaga, J. E. Austermann, E. L. Chapin, J. S. Dunlop, H. Ezawa, M. Halpern, B. Hatsukade, D. H. Hughes, R. Kawabe, S. Kim, K. Kohno, J. D. Lowenthal, A. Montaña, K. Nakanishi, T. Oshima, D. Sanders, D. Scott, N. Scoville, Y. Tamura, D. Welch, M. S. Yun, M. Zeballos
The Source Counts Of Submillimetre Galaxies Detected At 1.1 Mm, K. S. Scott, Grant W. Wilson, I. Aretxaga, J. E. Austermann, E. L. Chapin, J. S. Dunlop, H. Ezawa, M. Halpern, B. Hatsukade, D. H. Hughes, R. Kawabe, S. Kim, K. Kohno, J. D. Lowenthal, A. Montaña, K. Nakanishi, T. Oshima, D. Sanders, D. Scott, N. Scoville, Y. Tamura, D. Welch, M. S. Yun, M. Zeballos
Grant Wilson
The source counts of galaxies discovered at sub-millimetre and millimetre wavelengths provide important information on the evolution of infrared-bright galaxies. We combine the data from six blank-field surveys carried out at 1.1 mm with AzTEC, totalling 1.6 square degrees in area with root-mean-square depths ranging from 0.4 to 1.7 mJy, and derive the strongest constraints to date on the 1.1 mm source counts at flux densities S(1100) = 1-12 mJy. Using additional data from the AzTEC Cluster Environment Survey to extend the counts to S(1100) ~ 20 mJy, we see tentative evidence for an enhancement relative to the exponential drop …
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
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
How Do Star-Forming Galaxies At Z>3 Assemble Their Masses?, Kyoung-Soo Lee, Henry C. Ferguson, Tommy Wiklind, Tomas Dahlen, Mark E. Dickinson, Mauro Giavalisco, Normin Grogin, Casey Papovich, Hugo Messias, Yicheng Guo, Lihwai Lin
How Do Star-Forming Galaxies At Z>3 Assemble Their Masses?, Kyoung-Soo Lee, Henry C. Ferguson, Tommy Wiklind, Tomas Dahlen, Mark E. Dickinson, Mauro Giavalisco, Normin Grogin, Casey Papovich, Hugo Messias, Yicheng Guo, Lihwai Lin
Mauro Giavalisco
We investigate how star-forming galaxies typically assemble their masses at high redshift. Using the deep multi-wavelength coverage of the GOODS dataset, we measure stellar mass of a large sample of star-forming galaxies at z~4 and 5, and make a robust determination of stellar mass function (SMF). We report a broad correlation between stellar mass and UV luminosity, such that more UV-luminous galaxies are, on average, more massive. However, the correlation has a substantial intrinsic scatter evidenced by a non-negligible number of UV-faint but massive galaxies. Furthermore, the low-mass end of the SMF does not rise as steeply as the UV …
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
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
Candels: The Evolution Of Galaxy Rest-Frame Ultraviolet Colors From Z = 8 To 4, Steven L. Finkelstein, Casey Papovich, Brett Salmon, Kristian Finlator, Mark Dickinson, Henry C. Ferguson, Mauro Giavalisco, Anton M. Koekemoer, Naveen A. Reddy, Robert Bassett, Christopher J. Conselice, James C. Dunlop, S. M. Faber, Norman A. Grogin, Nimish P. Hathi, Dale D. Kocevski, Kamson Lai, Kyoung-Soo Lee, Ross J. Mclure, Bahram Mobasher, Jeffrey A. Newman
Candels: The Evolution Of Galaxy Rest-Frame Ultraviolet Colors From Z = 8 To 4, Steven L. Finkelstein, Casey Papovich, Brett Salmon, Kristian Finlator, Mark Dickinson, Henry C. Ferguson, Mauro Giavalisco, Anton M. Koekemoer, Naveen A. Reddy, Robert Bassett, Christopher J. Conselice, James C. Dunlop, S. M. Faber, Norman A. Grogin, Nimish P. Hathi, Dale D. Kocevski, Kamson Lai, Kyoung-Soo Lee, Ross J. Mclure, Bahram Mobasher, Jeffrey A. Newman
Mauro Giavalisco
We study the evolution of galaxy rest-frame ultraviolet (UV) colors in the epoch 4 < z < 8. We use new wide-field near-infrared data in GOODS-S from the CANDELS, HUDF09 and ERS programs to select galaxies via photometric redshift measurements. Our sample consists of 2812 candidate galaxies at z > 3.5, including 113 at z = 7 to 8. We fit the observed spectral energy distribution to a suite of synthetic stellar population models, and measure the value of the UV spectral slope (beta) from the best-fit model spectrum. The median value of beta evolves significantly from -1.82 (+0.00,-0.04) at z = 4, to -2.37 (+0.26,-0.06) at z = 7. Additionally, we find that faint galaxies at z = 7 have beta = -2.68 (+0.39,-0.24) (~ -2.4 after correcting for observational bias); this is redder than …
Aztec 1.1 Mm Observations Of The Mbm12 Molecular Cloud, M. J. Kim, S. Kim, S. Youn, M. S. Yun, Grant Wilson, I. Aretxaga, J. P. Williams, D. H. Hughes, A. Humphrey, J. E. Austermann, T. A. Perera, P. D. Mauskopf, L. Magnani, Y.-W. Kang
Aztec 1.1 Mm Observations Of The Mbm12 Molecular Cloud, M. J. Kim, S. Kim, S. Youn, M. S. Yun, Grant Wilson, I. Aretxaga, J. P. Williams, D. H. Hughes, A. Humphrey, J. E. Austermann, T. A. Perera, P. D. Mauskopf, L. Magnani, Y.-W. Kang
Grant Wilson
We present 1.1 mm observations of the dust continuum emission from the MBM12 high-latitude molecular cloud observed with the Astronomical Thermal Emission Camera (AzTEC) mounted on the James Clerk Maxwell Telescope on Mauna Kea, Hawaii. We surveyed a 6.34 deg$^2$ centered on MBM12, making this the largest area that has ever been surveyed in this region with submillimeter and millimeter telescopes. Eight secure individual sources were detected with a signal-to-noise ratio of over 4.4. These eight AzTEC sources can be considered to be real astronomical objects compared to the other candidates based on calculations of the false detection rate. The …
Candels: The Progenitors Of Compact Quiescent Galaxies At Z 2, Guillermo Barro, S. M. Faber, Pablo G. P´Erez-Gonz´Alez, David C. Koo, Christina C. Williams, Dale D. Kocevski, Jonathan R. Trump, Mark Mozena, Elizabeth Mcgrath, Arjen Van Der Wel, Stijn Wuyts, Eric F. Bell, Darren J. Croton, Avishai Dekel, M. L. N. Ashby, Henry C. Ferguson, Adriano Fontana, Mauro Giavalisco, Norman A. Grogin, Yicheng Guo, Nimish P. Hathi, Philip F. Hopkins, Kuang-Han Huang, Anton M. Koekemoer, Jeyhan S. Kartaltepe, Kyoung-Soo Lee, Jeffrey A. Newman, Lauren A. Porter, Joel R. Primack, Russell E. Ryan, David Rosario, Rachel S. Somerville
Candels: The Progenitors Of Compact Quiescent Galaxies At Z 2, Guillermo Barro, S. M. Faber, Pablo G. P´Erez-Gonz´Alez, David C. Koo, Christina C. Williams, Dale D. Kocevski, Jonathan R. Trump, Mark Mozena, Elizabeth Mcgrath, Arjen Van Der Wel, Stijn Wuyts, Eric F. Bell, Darren J. Croton, Avishai Dekel, M. L. N. Ashby, Henry C. Ferguson, Adriano Fontana, Mauro Giavalisco, Norman A. Grogin, Yicheng Guo, Nimish P. Hathi, Philip F. Hopkins, Kuang-Han Huang, Anton M. Koekemoer, Jeyhan S. Kartaltepe, Kyoung-Soo Lee, Jeffrey A. Newman, Lauren A. Porter, Joel R. Primack, Russell E. Ryan, David Rosario, Rachel S. Somerville
Mauro Giavalisco
We combine high-resolution HST/WFC3 images with multi-wavelength photometry to track the evolution of structure and activity of massive (log(M*) > 10) galaxies at redshifts z = 1.4 - 3 in two fields of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). We detect compact, star-forming galaxies (cSFGs) whose number densities, masses, sizes, and star formation rates qualify them as likely progenitors of compact, quiescent, massive galaxies (cQGs) at z = 1.5 - 3. At z > 2 most cSFGs have specific star-formation rates (sSFR = 10^-9 yr^-1) half that of typical, massive SFGs at the same epoch, and host X-ray luminous …
The Nature Of Extremely Red H-[4.5]>4 Galaxies Revealed With Seds And Candels, K. I. Caputi, J. S. Dunlop, R. J. Mclure, J, -S. Huang, G. G. Fazio, M. L. N. Ashby, M. Castellano, A. Fontana, M. Cirasuolo, O. Almaini, E. F. Bell, M. Dickinson, J. L. Donley, S. M. Faber, H. C. Ferguson, Mauro Giavalisco, N. A. Grogin, D. D. Kocevski, A. M. Koekemoer, D C. Koo, K. Lai, J. A. Newman, R. S. Somerville
The Nature Of Extremely Red H-[4.5]>4 Galaxies Revealed With Seds And Candels, K. I. Caputi, J. S. Dunlop, R. J. Mclure, J, -S. Huang, G. G. Fazio, M. L. N. Ashby, M. Castellano, A. Fontana, M. Cirasuolo, O. Almaini, E. F. Bell, M. Dickinson, J. L. Donley, S. M. Faber, H. C. Ferguson, Mauro Giavalisco, N. A. Grogin, D. D. Kocevski, A. M. Koekemoer, D C. Koo, K. Lai, J. A. Newman, R. S. Somerville
Mauro Giavalisco
We have analysed a sample of 25 extremely red H-[4.5]>4 galaxies, selected using 4.5 micron data from the Spitzer SEDS survey and deep H-band data from the Hubble Space Telescope (HST) CANDELS survey, over ~180 square arcmin of the UKIDSS Ultra Deep Survey (UDS) field. Our aim is to investigate the nature of this rare population of mid-infrared (mid-IR) sources that display such extreme near-to-mid-IR colours. Using up to 17-band photometry (U through 8.0 microns), we have studied in detail their spectral energy distributions, including possible degeneracies in the photometric redshift/internal extinction (zphot-Av) plane. Our sample appears to include …
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 …
Rest-Frame Uv--Optically Selected Galaxies At 2.3, Yicheng Guo, Mauro Giavalisco, Paolo Cassata, Henry C. Ferguson, Christina C. Williams, Mark Dickinson, Anton Koekemoer, Norman A. Grogin, Ranga-Ram Chary, Hugo Messias, Elena Tundo, Lihwai Lin, Seong-Kook Lee, Adriano Fontana, Andrea Grazian, Dale Kocevski, Kyoung-Soo Lee, Edward Villanueva, Arjen Van Der Wel
Rest-Frame Uv--Optically Selected Galaxies At 2.3, Yicheng Guo, Mauro Giavalisco, Paolo Cassata, Henry C. Ferguson, Christina C. Williams, Mark Dickinson, Anton Koekemoer, Norman A. Grogin, Ranga-Ram Chary, Hugo Messias, Elena Tundo, Lihwai Lin, Seong-Kook Lee, Adriano Fontana, Andrea Grazian, Dale Kocevski, Kyoung-Soo Lee, Edward Villanueva, Arjen Van Der Wel
Mauro Giavalisco
A new set of color selection criteria (VJL) analogous with the BzK method is designed to select both star-forming galaxies (SFGs) and passively-evolving galaxies (PEGs) at 2.310^{10}M_{Sun}) galaxies at 2.30.4) SFGs, which however, only account for ~20% of the number density of massive SFGs. We also use the mid-infrared fluxes to clean our PEG sample, and find that galaxy size can be used as a secondary criterion to effectively eliminate the contamination of dusty SFGs. The redshift distribution of the cleaned PEG sample peaks at z~2.5. We find 6 PEG candidates at z>3 and discuss possible methods to distinguish …
On The Clustering Of Sub-Millimeter Galaxies, Christina C. Williams, Mauro Giavalisco, Cristiano Porciani, Min S. Yun, Alexandra Pope, Kimberly S. Scott, Jason E. Austermann, Itziar Aretxaga, Bunyo Hatsukade, Kyoung-Soo Lee, Grant W. Wilson, J. Ryan Cybulski, David H. Hughes, Ryo Kawabe, Kotaro Kohno, Thushara Perera, F. Peter Schloerb
On The Clustering Of Sub-Millimeter Galaxies, Christina C. Williams, Mauro Giavalisco, Cristiano Porciani, Min S. Yun, Alexandra Pope, Kimberly S. Scott, Jason E. Austermann, Itziar Aretxaga, Bunyo Hatsukade, Kyoung-Soo Lee, Grant W. Wilson, J. Ryan Cybulski, David H. Hughes, Ryo Kawabe, Kotaro Kohno, Thushara Perera, F. Peter Schloerb
Mauro Giavalisco
We measure the angular two-point correlation function of sub-millimeter galaxies (SMGs) from 1.1-millimeter imaging of the COSMOS field with the AzTEC camera and ASTE 10-meter telescope. These data yields one of the largest contiguous samples of SMGs to date, covering an area of 0.72 degrees^2 down to a 1.26 mJy/beam (1-sigma) limit, including 189 (328) sources with S/N greater than 3.5 (3). We can only set upper limits to the correlation length r_0, modeling the correlation function as a power-law with pre-assigned slope. Assuming existing redshift distributions, we derive 68.3% confidence level upper limits of r_0 < 6-8 h^-1 Mpc at 3.7 mJy, and r_0 < 11-12 h^-1 Mpc at 4.2 mJy. Although consistent with most previous estimates, these upper limits imply that the real r_0 is likely smaller. This casts doubts on the robustness of claims that SMGs are characterized by significantly stronger spatial clustering, (and thus larger mass), than differently selected galaxies at high-redshift. Using Monte Carlo simulations we show that even strongly clustered distributions of galaxies can appear unclustered when sampled with limited sensitivity and coarse angular resolution common to current sub-millimeter surveys. The simulations, however, also show that unclustered distributions can appear strongly clustered under these circumstances. From the simulations, we predict that at our survey depth, a mapped area of two degrees^2 is needed to reconstruct the correlation function, assuming smaller beam sizes of future surveys (e.g. the Large Millimeter Telescope's 6" beam size). At present, robust measures of the clustering strength of bright SMGs appear to be below the reach of most observations.
Deep Near-Infrared Spectroscopy Of Passively Evolving Galaxies At Z & 1.4^1, M. Onodera, A. Renzini, M. Carollo, M. Cappellari, C. Mancini, V. Strazzullo, E. Daddi, N. Arimoto, R. Gobat, Y. Yamada, H. J. Mccracken, O. Ilbert, P. Capak, A. Cimatti, Mauro Giavalisco, M. Giavalisco, A. M. Koekemoer, X. Kong, S. Lilly, K. Motohara, K. Ohta, D. B. Sanders, N. Scoville, N. Tamura, Y. Taniguchi
Deep Near-Infrared Spectroscopy Of Passively Evolving Galaxies At Z & 1.4^1, M. Onodera, A. Renzini, M. Carollo, M. Cappellari, C. Mancini, V. Strazzullo, E. Daddi, N. Arimoto, R. Gobat, Y. Yamada, H. J. Mccracken, O. Ilbert, P. Capak, A. Cimatti, Mauro Giavalisco, M. Giavalisco, A. M. Koekemoer, X. Kong, S. Lilly, K. Motohara, K. Ohta, D. B. Sanders, N. Scoville, N. Tamura, Y. Taniguchi
Mauro Giavalisco
We present the results of new near-IR spectroscopic observations of passive galaxies at z & 1.4 in a concentration of BzK-selected galaxies in the COSMOS field. The observations have been conducted with Subaru/ MOIRCS, and have resulted in absorption lines and/or continuum detection for 18 out of 34 objects. This allows us to measure spectroscopic redshifts for a sample that is almost complete to KAB = 21. COSMOS photometric redshifts are found in fair agreement overall with the spectroscopic redshifts, with a standard deviation of ∼ 0.05; however, ∼ 30% of objects have photometric redshifts systematically underestimated by up to …
Origins Of The Extragalactic Background At 1mm From A Combined Analysis Of The Aztec And Mambo Data In Goods-N, Kyle Penner, Alexandra Pope, Edward L. Chapin, Thomas R. Greve, Frank Bertoldi, Mark Brodwin, Ranga-Ram Chary, Christopher J, Conselice, Kristen Coppin, Mauro Giavalisco, David H. Hughes, Rob J. Ivison, Thushara Perera, Douglas Scott, Kimberly Scott, Grant Wilson
Origins Of The Extragalactic Background At 1mm From A Combined Analysis Of The Aztec And Mambo Data In Goods-N, Kyle Penner, Alexandra Pope, Edward L. Chapin, Thomas R. Greve, Frank Bertoldi, Mark Brodwin, Ranga-Ram Chary, Christopher J, Conselice, Kristen Coppin, Mauro Giavalisco, David H. Hughes, Rob J. Ivison, Thushara Perera, Douglas Scott, Kimberly Scott, Grant Wilson
Mauro Giavalisco
We present a study of the cosmic infrared background, which is a measure of the dust obscured activity in all galaxies in the Universe. We venture to isolate the galaxies responsible for the background at 1mm; with spectroscopic and photometric redshifts we constrain the redshift distribution of these galaxies. We create a deep 1.16mm map (sigma ~ 0.5mJy) by combining the AzTEC 1.1mm and MAMBO 1.2mm datasets in GOODS-N. This combined map contains 41 secure detections, 13 of which are new. By averaging the 1.16mm flux densities of individually undetected galaxies with 24um flux densities > 25uJy, we resolve 31--45 per …
Improving The Estimation Of Star Formation Rates And Stellar Population Ages Of High-Redshift Galaxies From Broadband Photometry, Seong-Kook Lee, Henry C. Ferguson, Rachel S. Somerville, Tommy Wiklind, Mauro Giavalisco
Improving The Estimation Of Star Formation Rates And Stellar Population Ages Of High-Redshift Galaxies From Broadband Photometry, Seong-Kook Lee, Henry C. Ferguson, Rachel S. Somerville, Tommy Wiklind, Mauro Giavalisco
Mauro Giavalisco
We explore methods to improve the estimates of star formation rates and mean stellar population ages from broadband photometry of high redshift star-forming galaxies. We use synthetic spectral templates with a variety of simple parametric star formation histories to fit broadband spectral energy distributions. These parametric models are used to infer ages, star formation rates and stellar masses for a mock data set drawn from a hierarchical semi-analytic model of galaxy evolution. Traditional parametric models generally assume an exponentially declining rate of star-formation after an initial instantaneous rise. Our results show that star formation histories with a much more gradual …
Candels: The Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products And Mosaics, Anton M. Koekemoer, S. M. Faber, Henry C. Ferguson, Norman A. Grogin, Dale D. Kocevski, David C. Koo, Kamson Lai, Jennifer M. Lotz, Ray. A. Lucas, Elizabeth J. Mcgrath, Sara Ogaz, Abhijith Rajan, Adam G. Riess, Steve A. Rodney, Louis Strolger, Stefano Casertano, Marco Castellano, Tomas Dahlen, Mark Dickinson, Timothy Dolch, Adriano Fontana, Mauro Giavalisco, Andrea Grazian, Yicheng Guo, Nimish P. Hathi, Kuang-Han Huang, Arjen Van Der Wel, Hao-Jing Yan, Viviana Acquaviva, David M. Alexander, Omar Almaini, Matthew L. N. Ashby, Marco Barden, Eric F. Bell, Frédéric Bournaud, Thomas M. Brown, Karina I. Caputi, Paolo Cassata, Peter Challis, Ranga-Ram Chary, Edmond Cheung, Michele Cirasuolo, Christopher J. Conselice, Asantha Roshan, Darren J. Croton, Emanuele Daddi, Romeel Davé, Dulia F. De Mello, Loic De Ravel, Avishai Dekel, Jennifer L. Donley, James S. Dunlop, Aaron A. Dutton, David Elbaz, Giovanni G. Fazio, Alex F. Filippenko, Steven L. Finkelstein, Chris Frazer, Jonathan P. Gardner, Peter M. Garnavich, Eric Gawiser, Ruth Gruetzbauch, Will G. Hartley, Boris Häussler, Jessica Herrington, Philip F. Hopkins, Jia-Sheng Huang, Saurabh Jha, Andrew Johnson, Jeyhan S. Kartaltepe, Ali Ahmad Khostovan, Robert P. Kirshner, Caterina Lani, Kyoung-Soo Lee, Weidong Li, Piero Madau, Patrick J. Mccarthy, Daniel H. Mcintosh, Ross J. Mclure, Conor Mcpartland, Bahram Mobasher, Heidi Moreira, Alice Mortlock, Leonidas A. Moustakas, Mark Mozena, Kirpal Nandra, Jeffrey A. Newman, Jennifer L. Nielsen, Sami Niemi, Kai G. Noeske, Casey J. Papovich, Laura Pentericci, Alexandra Pope, Joel R. Primack, Swara Ravindranath, Naveen A. Reddy, Alvio Renzini, Hans-Walter Rix, Aday R. Robaina, David J. Rosario, Piero Rosati, Sara Salimbeni, Claudia Scarlata, Brian Siana, Luc Simard, Joseph Smidt, Diana Snyder, Rachel S. Somerville, Hyron Spinrad, Amber N. Straughn, Olivia Telford, Harry I. Teplitz, Jonathan R. Trump, Carlos Vargas, Carolin Villforth, Cory R. Wagner, Pat Wandro, Risa H. Wechsler, Benjamin J. Weiner, Tommy Wiklind, Vivienne Wild, Grant Wilson, Stijn Wuyts, Min S. Yun
Candels: The Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products And Mosaics, Anton M. Koekemoer, S. M. Faber, Henry C. Ferguson, Norman A. Grogin, Dale D. Kocevski, David C. Koo, Kamson Lai, Jennifer M. Lotz, Ray. A. Lucas, Elizabeth J. Mcgrath, Sara Ogaz, Abhijith Rajan, Adam G. Riess, Steve A. Rodney, Louis Strolger, Stefano Casertano, Marco Castellano, Tomas Dahlen, Mark Dickinson, Timothy Dolch, Adriano Fontana, Mauro Giavalisco, Andrea Grazian, Yicheng Guo, Nimish P. Hathi, Kuang-Han Huang, Arjen Van Der Wel, Hao-Jing Yan, Viviana Acquaviva, David M. Alexander, Omar Almaini, Matthew L. N. Ashby, Marco Barden, Eric F. Bell, Frédéric Bournaud, Thomas M. Brown, Karina I. Caputi, Paolo Cassata, Peter Challis, Ranga-Ram Chary, Edmond Cheung, Michele Cirasuolo, Christopher J. Conselice, Asantha Roshan, Darren J. Croton, Emanuele Daddi, Romeel Davé, Dulia F. De Mello, Loic De Ravel, Avishai Dekel, Jennifer L. Donley, James S. Dunlop, Aaron A. Dutton, David Elbaz, Giovanni G. Fazio, Alex F. Filippenko, Steven L. Finkelstein, Chris Frazer, Jonathan P. Gardner, Peter M. Garnavich, Eric Gawiser, Ruth Gruetzbauch, Will G. Hartley, Boris Häussler, Jessica Herrington, Philip F. Hopkins, Jia-Sheng Huang, Saurabh Jha, Andrew Johnson, Jeyhan S. Kartaltepe, Ali Ahmad Khostovan, Robert P. Kirshner, Caterina Lani, Kyoung-Soo Lee, Weidong Li, Piero Madau, Patrick J. Mccarthy, Daniel H. Mcintosh, Ross J. Mclure, Conor Mcpartland, Bahram Mobasher, Heidi Moreira, Alice Mortlock, Leonidas A. Moustakas, Mark Mozena, Kirpal Nandra, Jeffrey A. Newman, Jennifer L. Nielsen, Sami Niemi, Kai G. Noeske, Casey J. Papovich, Laura Pentericci, Alexandra Pope, Joel R. Primack, Swara Ravindranath, Naveen A. Reddy, Alvio Renzini, Hans-Walter Rix, Aday R. Robaina, David J. Rosario, Piero Rosati, Sara Salimbeni, Claudia Scarlata, Brian Siana, Luc Simard, Joseph Smidt, Diana Snyder, Rachel S. Somerville, Hyron Spinrad, Amber N. Straughn, Olivia Telford, Harry I. Teplitz, Jonathan R. Trump, Carlos Vargas, Carolin Villforth, Cory R. Wagner, Pat Wandro, Risa H. Wechsler, Benjamin J. Weiner, Tommy Wiklind, Vivienne Wild, Grant Wilson, Stijn Wuyts, Min S. Yun
Mauro Giavalisco
This paper describes the Hubble Space Telescope imaging data products and data reduction procedures for the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS). This survey is designed to document the evolution of galaxies and black holes at $z\sim1.5-8$, and to study Type Ia SNe beyond $z>1.5$. Five premier multi-wavelength sky regions are selected, each with extensive multiwavelength observations. The primary CANDELS data consist of imaging obtained in the Wide Field Camera 3 / infrared channel (WFC3/IR) and UVIS channel, along with the Advanced Camera for Surveys (ACS). The CANDELS/Deep survey covers \sim125 square arcminutes within GOODS-N and GOODS-S, …
A Z=1.82 Analog Of Local Ultra-Massive Elliptical Galaxies, M. Onodera, E. Daddi, R. Gobat, M. Cappellari, N. Arimoto, A. Renzini, Y. Yamada, H. J. Mccracken, C. Mancini, P. Capak, M. Carollo, A. Cimatti, Mauro Giavalisco, O. Ilbert, X. Kong, S. Lilly, K. Motohara, K. Ohta, D. B. Sanders, N. Scoville, N. Tamura, Y. Taniguchi
A Z=1.82 Analog Of Local Ultra-Massive Elliptical Galaxies, M. Onodera, E. Daddi, R. Gobat, M. Cappellari, N. Arimoto, A. Renzini, Y. Yamada, H. J. Mccracken, C. Mancini, P. Capak, M. Carollo, A. Cimatti, Mauro Giavalisco, O. Ilbert, X. Kong, S. Lilly, K. Motohara, K. Ohta, D. B. Sanders, N. Scoville, N. Tamura, Y. Taniguchi
Mauro Giavalisco
We present observations of a very massive galaxy at z=1.82 which show that its morphology, size, velocity dispersion and stellar population properties that are fully consistent with those expected for passively evolving progenitors of today's giant ellipticals. These findings are based on a deep optical rest-frame spectrum obtained with the Multi-Object InfraRed Camera and Spectrograph (MOIRCS) on the Subaru telescope of a high-z passive galaxy candidate (pBzK) from the COSMOS field, for which we accurately measure its redshift of z=1.8230 and obtain an upper limit on its velocity dispersion sigma_star<326 km/s. By detailed stellar population modeling of both the galaxy broad-band SED and the rest-frame optical spectrum we derive a star-formation-weighted age and formation redshift of t_sf~1-2 Gyr and z_form~2.5-4, and a stellar mass of M_star~(3-4)x10^{11} M_sun. This is in agreement with a virial mass limit of M_vir<7x10^{11}M_sun, derived from the measured sigma_star value and stellar half-light radius, as well as with the dynamical mass limit based on the Jeans equations. In contrast with previously reported super-dense passive galaxies at z~2, the present galaxy at z=1.82 appears to have both size and velocity dispersion similar to early-type galaxies in the local Universe with similar stellar mass. This suggests that z~2 massive and passive galaxies may exhibit a wide range of properties, then possibly following quite different evolutionary histories from z~2 to z=0.
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 …
A Deep Hst Search For Escaping Lyman Continuum Flux At Z~1.3: Evidence For An Evolving Ionizing Emissivity, Brian Siana, Harry I. Teplitz, Henry C. Ferguson, Thomas M. Brown, Mauro Giavalisco, Mark Dickinson, Carrie R. Bridge, Ranga-Ram Chary, Duilia F. De Mello, Christopher J. Conselice, Jonathan P. Gardner, James W. Colbert, Claudia Scarlata
A Deep Hst Search For Escaping Lyman Continuum Flux At Z~1.3: Evidence For An Evolving Ionizing Emissivity, Brian Siana, Harry I. Teplitz, Henry C. Ferguson, Thomas M. Brown, Mauro Giavalisco, Mark Dickinson, Carrie R. Bridge, Ranga-Ram Chary, Duilia F. De Mello, Christopher J. Conselice, Jonathan P. Gardner, James W. Colbert, Claudia Scarlata
Mauro Giavalisco
We have obtained deep Hubble Space Telescope far-UV images of 15 starburst galaxies at z~1.3 in the GOODS fields to search for escaping Lyman continuum photons. These are the deepest far-UV images m_{AB}=28.7, 3\sigma, 1" diameter) over this large an area (4.83 arcmin^2) and provide the best escape fraction constraints for any galaxy at any redshift. We do not detect any individual galaxies, with 3\sigma limits to the Lyman Continuum (~700 \AA) flux 50--149 times fainter (in f_nu) than the rest-frame UV (1500 \AA) continuum fluxes. Correcting for the mean IGM attenuation (factor ~2), as well as an intrinsic stellar …
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 …
The Rising Star-Formation Histories Of Distant Galaxies And Implications For Gas Accretion With Time, Casey Papovich, Steven L. Finkelstein, Henry C. Ferguson, Jennifer M. Lotz, Mauro Giavalisco
The Rising Star-Formation Histories Of Distant Galaxies And Implications For Gas Accretion With Time, Casey Papovich, Steven L. Finkelstein, Henry C. Ferguson, Jennifer M. Lotz, Mauro Giavalisco
Mauro Giavalisco
Distant galaxies show correlations between their current star-formation rates (SFRs) and stellar masses, implying that their star-formation histories (SFHs) are highly similar. Moreover, observations show that the UV luminosities and stellar masses grow from z=8 to 3, implying that the SFRs increase with time. We compare the cosmologically averaged evolution in galaxies at 3 < z < 8 at constant comoving number density, n = 2 x 10^-4 Mpc^-3. This allows us to study the evolution of stellar mass and star formation in the galaxy predecessors and descendants in ways not possible using galaxies selected at constant stellar mass or SFR, quantities that evolve strongly in time. We show that the average SFH of these galaxies increase smoothly from z=8 to 3 as SFR ~ t^alpha with alpha = 1.7 +/- 0.2. This conflicts with assumptions that the SFR is either constant or declines exponentially in time. We show that the stellar mass growth in these galaxies is consistent with this derived SFH. This provides evidence that the slope of the high-mass end of the IMF is approximately Salpeter unless the duty cycle of star formation is much less than unity. We argue that these relations follow from gas accretion (either through accretion or delivered by mergers) coupled with galaxy disk growth under the assumption that the SFR depends on the local gas surface density. This predicts that gas fractions decrease from z=8 to 3 on average as f_gas ~ (1+z)^0.9 for galaxies with this number density. The implied galaxy gas accretion rates at z > 4 are as fast and may even exceed the SFR: this is the "gas accretion epoch". At z < 4 the SFR overtakes the implied gas accretion rate, indicating a period where galaxies consume gas faster than it is acquired. At z < 3, galaxies with this number density depart from these relations implying that star formation and gas accretion are slowed at later times.
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
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 …
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
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. …