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NuSTAR Detection of the Blazar B2 1023+25 at Redshift 5.3

Sbarrato, T. and Tagliaferri, G. and Ghisellini, G. and Perri, M. and Puccetti, S. and Baloković, M. and Nardini, M. and Stern, D. and Boggs, S. E. and Brandt, W. N. and Christensen, F. E. and Giommi, P. and Greiner, J. and Hailey, C. J. and Harrison, F. A. and Hovatta, T. and Madejski, G. M. and Rau, A. and Schady, P. and Sudilovsky, V. and Urry, C. M. and Zhang, W. W. (2013) NuSTAR Detection of the Blazar B2 1023+25 at Redshift 5.3. Astrophysical Journal, 777 (2). Art. No. 147. ISSN 0004-637X. doi:10.1088/0004-637X/777/2/147.

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B2 1023+25 is an extremely radio-loud quasar at z = 5.3 that was first identified as a likely high-redshift blazar candidate in the SDSS+FIRST quasar catalog. Here, we use the Nuclear Spectroscopic Telescope Array (NuSTAR) to investigate its non-thermal jet emission, whose high-energy component we detected in the hard X-ray energy band. The X-ray flux is ~ 5.5 x 10^(-14)erg cm^(-2) s^(-1) (5-10 keV) and the photon spectral index is Γ_X ≃ 1.3-1.6. Modeling the full spectral energy distribution, we find that the jet is oriented close to the line of sight, with a viewing angle of ~3°, and has significant Doppler boosting, with a large bulk Lorentz factor ~13, which confirms the identification of B2 1023+25 as a blazar. B2 1023+25 is the first object at redshift larger than 5 detected by NuSTAR, demonstrating the ability of NuSTAR to investigate the early X-ray universe and to study extremely active supermassive black holes located at very high redshift.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Puccetti, S.0000-0002-2734-7835
Baloković, M.0000-0003-0476-6647
Stern, D.0000-0003-2686-9241
Boggs, S. E.0000-0001-9567-4224
Brandt, W. N.0000-0002-0167-2453
Christensen, F. E.0000-0001-5679-1946
Harrison, F. A.0000-0003-2992-8024
Hovatta, T.0000-0002-2024-8199
Rau, A.0000-0001-5990-6243
Urry, C. M.0000-0002-0745-9792
Zhang, W. W.0000-0002-1426-9698
Additional Information:© 2013 American Astronomical Society. Received 2013 August 12; accepted 2013 September 10; published 2013 October 23. We thank the anonymous referee for useful comments. We acknowledge financial support from the ASI-INAF grant I/037/12/0. This work was supported under NASA Contract No. NNG08FD60C and made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made also use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (Caltech, USA). The scientific results reported in this article are based in part on observations made by the Chandra X-ray Observatory and published previously in cited articles. This publication 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, funded by the National Aeronautics and Space Administration. Part of this work is based on archival data, software, or on-line services provided by the ASDC. This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASDC, Italy. Part of the funding for GROND (both hardware as well as personnel) was generously granted from the Leibniz Prize to Professor G. Hasinger (DFG grant HA 1850/28-1). Support for CARMA construction was derived from the Gordon and Betty Moore Foundation, the Kenneth T. and Eileen L. Norris Foundation, the James S. McDonnell Foundation, the Associates of the California Institute of Technology, the University of Chicago, the states of California, Illinois, and Maryland, and the National Science Foundation. Ongoing CARMA development and operations are supported by the National Science Foundation under a cooperative agreement, and by the CARMA partner universities. The operation of the OVRO 40 m telescope is supported by NASA awards NNX08AW31G and NNX11AO43G and NSF awards AST-0808050 and AST-1109911. M.B. acknowledges support from an International Fulbright Science and Technology Award.
Group:NuSTAR, Space Radiation Laboratory
Funding AgencyGrant Number
Agenzia Spaziale Italiana (ASI)I/037/12/0-011/13
Deutsche Forschungsgemeinschaft (DFG)HA 1850/28-1
Gordon and Betty Moore FoundationUNSPECIFIED
Kenneth T. and Eileen L. Norris FoundationUNSPECIFIED
James S. McDonnell FoundationUNSPECIFIED
Caltech AssociatesUNSPECIFIED
University of ChicagoUNSPECIFIED
States of CaliforniaUNSPECIFIED
State of IllinoisUNSPECIFIED
State of MarylandUNSPECIFIED
CARMA partner universitiesUNSPECIFIED
International Fulbright Science and Technology AwardUNSPECIFIED
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Subject Keywords: galaxies: active; quasars: general; quasars: individual (B2 1023+25); X-rays: general
Issue or Number:2
Record Number:CaltechAUTHORS:20131202-132341132
Persistent URL:
Official Citation:NuSTAR Detection of the Blazar B2 1023+25 at Redshift 5.3 T. Sbarrato et al. 2013 ApJ 777 147
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:42775
Deposited By: Ruth Sustaita
Deposited On:02 Dec 2013 22:15
Last Modified:10 Nov 2021 16:28

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