| Téléchargement | - Voir la version finale : The Subaru high-z quasar survey: discovery of faint z ~ 6 quasars (PDF, 1.4 Mio)
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| DOI | Trouver le DOI : https://doi.org/10.1088/0004-637X/798/1/28 |
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| Auteur | Rechercher : Kashikawa, Nobunari; Rechercher : Ishizaki, Yoshifumi; Rechercher : Willott, Chris J.1; Rechercher : Onoue, Masafusa; Rechercher : Im, Myungshin; Rechercher : Furusawa, Hisanori; Rechercher : Toshikawa, Jun; Rechercher : Ishikawa, Shogo; Rechercher : Niino, Yuu; Rechercher : Shimasaku, Kazuhiro; Rechercher : Ouchi, Masami; Rechercher : Hibon, Pascale |
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| Affiliation | - Conseil national de recherches Canada. Herzberg en astronomie et en astrophysique
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| Format | Texte, Article |
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| Résumé | We present the discovery of one or two extremely faint z ~ 6 quasars in 6.5 deg2 utilizing a unique capability of the wide-field imaging of the Subaru/Suprime-Cam. The quasar selection was made in (i'-zB ) and (zB -zR ) colors, where zB and zR are bandpasses with central wavelengths of 8842 Å and 9841 Å, respectively. The color selection can effectively isolate quasars at z ~ 6 from M/L/T dwarfs without the J-band photometry down to zR < 24.0, which is 3.5 mag deeper than the Sloan Digital Sky Survey (SDSS). We have selected 17 promising quasar candidates. The follow-up spectroscopy for seven targets identified one apparent quasar at z = 6.156 with M 1450 = –23.10. We also identified one possible quasar at z = 6.041 with a faint continuum of M 1450 = –22.58 and a narrow Lyα emission with HWHM =427 km s–1, which cannot be distinguished from Lyman α emitters. We derive the quasar luminosity function at z ~ 6 by combining our faint quasar sample with the bright quasar samples by SDSS and CFHQS. Including our data points invokes a higher number density in the faintest bin of the quasar luminosity function than the previous estimate employed. This suggests a steeper faint-end slope than lower z, though it is yet uncertain based on a small number of spectroscopically identified faint quasars, and several quasar candidates still remain to be diagnosed. The steepening of the quasar luminosity function at the faint end does increase the expected emission rate of the ionizing photon; however, it only changes by a factor of approximately two to six. This was found to still be insufficient for the required photon budget of reionization at z ~ 6. |
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| Date de publication | 2014-12-16 |
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| Maison d’édition | American Astronomical Society |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Numéro NPARC | 23001695 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | f49ae01c-74b7-4b68-b63f-1987099d531c |
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| Enregistrement créé | 2017-03-20 |
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| Enregistrement modifié | 2020-05-30 |
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