Issue |
A&A
Volume 643, November 2020
|
|
---|---|---|
Article Number | A149 | |
Number of page(s) | 27 | |
Section | Extragalactic astronomy | |
DOI | https://doi.org/10.1051/0004-6361/202038756 | |
Published online | 17 November 2020 |
J-PLUS: Unveiling the brightest end of the Lyα luminosity function at 2.0 < z < 3.3 over 1000 deg2⋆
1
Centro de Estudios de Física del Cosmos de Aragón, Plaza San Juan 1, planta 2, 44001 Teruel, Spain
e-mail: dspinoso@cefca.es
2
PlantTech Research Institute Limited, South British House, 4th Floor, 35 Grey Street, Tauranga 3110, New Zealand
3
Donostia International Physics Center, Paseo Manuel de Lardizabal, 4, 20018 Donostia-San Sebastián (Gipuzkoa), Spain
4
IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
5
Department of Physics, Lancaster University, Lancaster LA1 4YB, UK
6
Institute for Multi-messenger Astrophysics and Cosmology, Department of Physics, Missouri University of Science and Technology, 1315 N. Pine St., Rolla, MO 65409, USA
7
Universidade de São Paulo, Instituto de Astronomia, Geofísica e Ciências Atmosféricas, 05508090 São Paulo, SP, Brazil
8
Asociación Astrofísica para la Promoción de la Investigación, Instrumentación y su Desarrollo, 38205 La Laguna, Tenerife, Spain
9
Observatório Nacional/MCTIC, Rua José Cristino, 77, CEP 20921-400 São Cristóvão, Rio de Janeiro (RJ), Brazil
10
Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
11
Institució Catalana de Recerca i Estudis Avançats, 08034 Barcelona, Spain
12
Institute for Advanced Study, Princeton, NJ 08544, USA
13
Department of Astronomy, University of Michigan, Ann Arbor, MI 48109-1107, USA
14
Instituto de Astrofísica de Andalucía – CSIC, Apdo 3004, 18080 Granada, Spain
15
Departamento de Física, Universidade Federal do Rio Grande do Norte, 59078-970 Natal, RN, Brazil
16
Instituto Nacional de Pesquisas Espaciais. INPE/CRN, 59076-740 Natal, RN, Brazil
Received:
25
June
2020
Accepted:
8
September
2020
We present the photometric determination of the bright end of the Lyα luminosity function (LF; at LLyα ≳ 1043.3 erg s−1) within four redshift windows (Δ z < 0.16) in the interval 2.2 ≲ z ≲ 3.3. Our work is based on the Javalambre Photometric Local Universe Survey (J-PLUS) first data release, which provides multiple narrow-band measurements over ∼1000 deg2, with limiting magnitude r ∼ 22. The analysis of high-z Lyα-emitting sources over such a wide area is unprecedented and allows us to select approximately 14 500 hyper-bright (LLyα > 1043.3 erg s−1) Lyα-emitting candidates. We test our selection with two spectroscopic programs at the GTC telescope, which confirm ∼89% of the targets as line-emitting sources, with ∼64% being genuine z ∼ 2.2 quasars (QSOs). We extend the 2.2 ≲ z ≲ 3.3 Lyα LF for the first time above LLyα ∼ 1044 erg s−1 and down to densities of ∼10−8 Mpc−3. Our results unveil the Schechter exponential decay of the brightest-end of the Lyα LF in great detail, complementing the power-law component of previous determinations at 43.3 ≲ Log10(LLyα/erg s−1) ≲ 44. We measure Φ* = (3.33 ± 0.19)×10−6, Log(L*) = 44.65 ± 0.65, and α = −1.35 ± 0.84 as an average over the probed redshifts. These values are significantly different from the typical Schechter parameters measured for the Lyα LF of high-z star-forming Lyman-α emitters (LAEs). This implies that z > 2 AGNs/QSOs (likely dominant in our samples) are described by a structurally different LF from that used to describe z > 2 star-forming LAEs, namely LQSOs* ~ 100LLAEs* and ΦQSOs* ~ 10−3 ΦLAEs*, with the transition between the two LFs happening at LLyα ∼ 1043.5 erg s−1. This supports the scenario in which Lyα-emitting AGNs/QSOs are the most abundant class of z ≳ 2 Lyα emitters at LLyα ≳ 1043.3 erg s−1. Finally, we suggest that a significant number of these z ≳ 2 AGNs/QSOs (∼60% of our samples) are currently misclassified as stars based on their broad-band colours, but are identified for the first time as high-z line-emitters by our narrow-band-based selection.
Key words: galaxies: luminosity function / mass function / galaxies: high-redshift / quasars: emission lines / techniques: photometric / methods: observational / surveys
Catalogs are available in electronic form both on the J-PLUS website at https://www.j-plus.es/ancillarydata/dr1_lya_emitting_candidates and at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/643/A149
© ESO 2020
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.