Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/29914
Title: | UV slope of z ∼ 3 bright (L > L*) Lyman-break galaxies in the COSMOS field | Authors: | Pilo, S. CASTELLANO, MARCO FONTANA, Adriano GRAZIAN, Andrea Boutsia, K. PENTERICCI, Laura GIALLONGO, Emanuele MERLIN, Emiliano PARIS, Diego SANTINI, Paola |
Issue Date: | 2019 | Journal: | ASTRONOMY & ASTROPHYSICS | Number: | 626 | First Page: | A45 | Abstract: | Context. The analysis of the UV slope β of Lyman-break galaxies (LBG) at different luminosities and redshifts is fundamental for understanding their physical properties, and in particular, their dust extinction. <BR /> Aims: We analyse a unique sample of 517 bright (L > L<SUP>*</SUP>) LBGs at redshift z ∼ 3 in order to characterise the distribution of their UV slopes β and infer their dust extinction under standard assumptions. <BR /> Methods: We exploited multi-band observations over 750 arcmin<SUP>2</SUP> of the COSMOS field that were acquired with three different ground-based facilities: the Large Binocular Camera (LBC) on the Large Binocular Telescope (LBT), the Suprime-Cam on the SUBARU telescope, and the VIRCAM on the VISTA telescope (ULTRAVISTA DR2). Our multi-band photometric catalogue is based on a new method that is designed to maximise the signal-to-noise ratio in the estimate of accurate galaxy colours from images with different point spread functions (PSF). We adopted an improved selection criterion based on deep Y-band data to isolate a sample of galaxies at z ∼ 3 to minimise selection biases. We measured the UV slopes (β) of the objects in our sample and then recovered the intrinsic probability density function of β values (PDF(β)), taking into account the effect of observational uncertainties through detailed simulations. <BR /> Results: The galaxies in our sample are characterised by mildly red UV slopes with ⟨β⟩≃ - 1.70 throughout the enitre luminosity range that is probed by our data (-24 ≲ M<SUB>1600</SUB> ≲ -21). The resulting dust-corrected star formation rate density (SFRD) is log(SFRD)≃ - 1.6 M<SUB>☉</SUB> yr<SUP>-1</SUP> Mpc<SUP>-3</SUP>, corresponding to a contribution of about 25% to the total SFRD at z ∼ 3 under standard assumptions. Conclusions: Ultra-bright LBGs at z ∼ 3 match the known trends, with UV slopes being redder at decreasing redshifts, and brighter galaxies being more highly dust extinct and more frequently star-forming than fainter galaxies. | URI: | http://hdl.handle.net/20.500.12386/29914 | URL: | https://www.aanda.org/articles/aa/full_html/2019/06/aa34442-18/aa34442-18.html | ISSN: | 0004-6361 | DOI: | 10.1051/0004-6361/201834442 | Bibcode ADS: | 2019A&A...626A..45P | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
1901.11302.pdf | postprint | 2.39 MB | Adobe PDF | View/Open |
aa34442-18.pdf | Pdf editoriale | 3.9 MB | Adobe PDF | View/Open |
Page view(s)
128
checked on Sep 11, 2024
Download(s)
43
checked on Sep 11, 2024
Google ScholarTM
Check
Altmetric
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.