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Full-Text Articles in Physical Sciences and Mathematics
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 …
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
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
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. …
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
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
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
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
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
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
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
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
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
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
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
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.
Biases And Uncertainties In Physical Parameter Estimates Of Lyman Break Galaxies From Broad-Band Photometry, Seong-Kook Lee, Rafal Idzi, Henry C. Ferguson, Rachel S. Somerville, Tommy Wiklind, Mauro Giavalisco
Biases And Uncertainties In Physical Parameter Estimates Of Lyman Break Galaxies From Broad-Band Photometry, Seong-Kook Lee, Rafal Idzi, Henry C. Ferguson, Rachel S. Somerville, Tommy Wiklind, Mauro Giavalisco
Mauro Giavalisco
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 broad-band photometry. By combining LCDM hierarchical structure formation theory, semi-analytic 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 broad-band spectral energy distributions (SEDs) of these model LBGs are then analysed by fitting galaxy template SEDs derived from stellar population synthesis models with smoothly declining SFRs. We compare the …