Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published January 20, 2017 | Submitted + Published
Journal Article Open

NuSTAR Observations of WISE J1036+0449, a Galaxy at z ~ 1 Obscured by Hot Dust

Abstract

Hot dust-obscured galaxies (hot DOGs), selected from Wide-Field Infrared Survey Explorer's all-sky infrared survey, host some of the most powerful active galactic nuclei known and may represent an important stage in the evolution of galaxies. Most known hot DOGs are located at z > 1.5, due in part to a strong bias against identifying them at lower redshift related to the selection criteria. We present a new selection method that identifies 153 hot DOG candidates at z ~ 1, where they are significantly brighter and easier to study. We validate this approach by measuring a redshift z = 1.009 and finding a spectral energy distribution similar to that of higher-redshift hot DOGs for one of these objects, WISE J1036+0449 (L_(Bol ≃ 8 x 10^(46) erg s^(-1)). We find evidence of a broadened component in Mg II, which would imply a black hole mass of M_(BH) ≃ 2 x 10^8 M⊙ and an Eddington ratio of λ_(Edd) ≃ 2.7. WISE J1036+0449 is the first hot DOG detected by the Nuclear Spectroscopic Telescope Array, and observations show that the source is heavily obscured, with a column density of N_H ≃ (2-15) x 10^(23) cm^(-2). The source has an intrinsic 2–10 keV luminosity of ~6 x 10^(44) erg s^(-1), a value significantly lower than that expected from the mid-infrared/X-ray correlation. We also find that other hot DOGs observed by X-ray facilities show a similar deficiency of X-ray flux. We discuss the origin of the X-ray weakness and the absorption properties of hot DOGs. Hot DOGs at z ≾ 1 could be excellent laboratories to probe the characteristics of the accretion flow and of the X-ray emitting plasma at extreme values of the Eddington ratio.

Additional Information

© 2017 The American Astronomical Society. Received 2016 September 3; revised 2016 October 27; accepted 2016 November 10; published 2017 January 20. We thank the referee for a very prompt report that helped to improve the article. This work makes use of data products from the Wide-Field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology (Caltech). WISE is funded by the National Aeronautics and Space Administration (NASA). Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership between Caltech, the University of California, and NASA. Use of the observatory was made possible by the generous financial support of the W.M. Keck Foundation. This work makes use of data from the NuSTAR mission, a project led by Caltech, managed by the Jet Propulsion Laboratory, and funded by NASA. We thank the NuSTAR Operations, Software, and Calibration teams for their support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software, jointly developed by the ASI Science Data Center (Italy) and Caltech. This work has made use of the NASA/IPAC Infrared Science Archive and NASA/IPAC Extragalactic Database, which are operated by the Jet Propulsion Laboratory, Caltech, under contract with NASA. This material is based upon work supported by NASA under Proposal No. 13-ADAP13-0092, issued through the Astrophysics Data Analysis Program. We thank M. Karouzos and C.S. Chang for their comments on the manuscript. We acknowledge financial support from CONICYT-Chile grants "EMBIGGEN" Anillo ACT1101 (C.R., E.T., F.E.B.); FONDECYT 1141218 (C.R., F.E.B.), 3140436 (R.N.), and 1151408 (R.A.); and Basal-CATA PFB–06/2007 (C.R., F.E.B., E.T.) and from the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to the Millennium Institute of Astrophysics (F.E.B.). C.R. acknowledges support from the China-CONICYT fund. P.G. thanks the STFC for their support [grant reference ST/J003697/2], and W.N.B. acknowledges financial support from NuSTAR subcontract 44A–1092750. P.B. is supported by an STFC studentship. A.C. acknowledges support from ASI/INAF grant I/037/12/0011/13 and the Caltech Kingsley visitor program. T.D.-S. acknowledges support from ALMA-CONICYT project 31130005 and FONDECYT 1151239. S.M.L. is supported by an appointment to the NASA Postdoctoral Program at the NASA Goddard Space Flight Center, administered by the Universities Space Research Association under contract with NASA. Facilities: Chandra - , NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, Swift - Swift Gamma-Ray Burst Mission, XMM-Newton - Newton X-Ray Multimirror Mission satellite, WISE - Wide-field Infrared Survey Explorer, Keck

Attached Files

Published - Ricci_2017_ApJ_835_105.pdf

Submitted - 1609.04808v2.pdf

Files

1609.04808v2.pdf
Files (3.4 MB)
Name Size Download all
md5:f9ab195e74c02f80ece20f548d756eff
1.2 MB Preview Download
md5:ff60fb94ffe8208efa8325fc8c5317f7
2.2 MB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 24, 2023