A Caltech Library Service

Discovery of an Enormous Lyα Nebula in a Massive Galaxy Overdensity at z = 2.3

Cai, Zheng and Fan, Xiaohui and Yang, Yujin and Bian, Fuyan and Prochaska, J. Xavier and Zabludoff, Ann and McGreer, Ian and Zheng, Zhen-Ya and Greenberg, Richard and Cantalupo, Sebastiano and Frye, Brenda and Hamden, Erika and Jiang, Linhua and Kashikawa, Nobunari and Wang, Ran (2017) Discovery of an Enormous Lyα Nebula in a Massive Galaxy Overdensity at z = 2.3. Astrophysical Journal, 837 (1). Art. No. 71. ISSN 0004-637X.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


Enormous Lyα nebulae (ELANe), unique tracers of galaxy density peaks, are predicted to lie at the nodes and intersections of cosmic filamentary structures. Previous successful searches for ELANe have focused on wide-field narrowband surveys or have targeted known sources such as ultraluminous quasi-stellar objects (QSOs) or radio galaxies. Utilizing groups of coherently strong Lyα absorptions, we have developed a new method to identify high-redshift galaxy overdensities and have identified an extremely massive overdensity, BOSS1441, at z = 2-3. In its density peak, we discover an ELAN that is associated with a relatively faint continuum. To date, this object has the highest diffuse Lyα nebular luminosity of L_(nebula) = 5.1 ± 0.1 x 10^(44) erg s^(−1). Above the 2σ surface brightness limit of SB Lyα = 4.8 x 10^(-18) erg s^(−1) cm^(−2) arcsec^(−2), this nebula has an end-to-end spatial extent of 442 kpc. This radio-quiet source also has extended C IV λ1549 and He II λ1640 emission on ≳ 30 kpc scales. Note that the Lyα, He II, and C IV emissions all have double-peaked line profiles. Each velocity component has an FWHM of ≈700–1000 km s^(−1). We argue that this Lyα nebula could be powered by shocks due to an active galactic nucleus–driven outflow or photoionization by a strongly obscured source.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Cai, Zheng0000-0001-8467-6478
Fan, Xiaohui0000-0003-3310-0131
Yang, Yujin0000-0003-3078-2763
Prochaska, J. Xavier0000-0002-7738-6875
Zabludoff, Ann0000-0001-6047-8469
McGreer, Ian0000-0002-3461-5228
Cantalupo, Sebastiano0000-0001-5804-1428
Jiang, Linhua0000-0003-4176-6486
Wang, Ran0000-0003-4956-5742
Additional Information:© 2017 The American Astronomical Society. Received 2016 September 13; revised 2017 January 20; accepted 2017 January 24; published 2017 March 3. Z.C. acknowledges the valuable comments from Fabrizio Arrigoni Battaia, Joe Hennawi, and Arjue Dey. Z.C., X.F., and I.M. thank the support from the US NSF grant AST 11-07682. Z.C. and J.X.P. acknowledge support from NSF AST-1412981. Y.Y.'s research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF 2016R1C1B2007782). A.Z. acknowledges support from NSF grant AST-0908280 and NASA grant ADP-NNX10AD47G. S.C. gratefully acknowledges support from Swiss National Science Foundation grant PP00P2_163824. N.K. acknowledges support from the JSPS grant 15H03645. This work is based on observations at Kitt Peak National Observatory, National Optical Astronomy Observatory (NOAO Prop. ID: 2013A-0434; PI: Z. Cai; NOAO Prop. ID: 2014A-0395; PI: Z. Cai), which is operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation. The authors are honored to be permitted to conduct astronomical research on Iolkam Du'ag (Kitt Peak), a mountain with particular significance to the Tohono O'odham. The LBT is an international collaboration among institutions in the United States, Italy, and Germany. The LBT Corporation partners are The University of Arizona on behalf of the Arizona university system; Instituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University; and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia.
Group:Space Astrophysics Laboratory
Funding AgencyGrant Number
NSFAST 11-07682
National Research Foundation of Korea2016R1C1B2007782
Swiss National Science Foundation (SNSF)PP00P2_163824
Japan Society for the Promotion of Science (JSPS)15H03645
Subject Keywords:galaxies: high-redshift, intergalactic medium
Issue or Number:1
Record Number:CaltechAUTHORS:20170311-205211262
Persistent URL:
Official Citation:Zheng Cai et al 2017 ApJ 837 71
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:75042
Deposited By: Deborah Miles
Deposited On:06 Apr 2017 18:10
Last Modified:04 Nov 2019 22:48

Repository Staff Only: item control page