A Caltech Library Service

Constraints on the Spacetime Metric around Seven “Bare” AGNs Using X-Ray Reflection Spectroscopy

Tripathi, Ashutosh and Yan, Jinli and Yang, Yuchan and Yan, Yunfeng and Garnham, Marcus and Yao, Yu and Li, Songcheng and Ding, Ziyu and Abdikamalov, Askar B. and Ayzenberg, Dimitry and Bambi, Cosimo and Dauser, Thomas and García, Javier A. and Jiang, Jiachen and Nampalliwar, Sourabh (2019) Constraints on the Spacetime Metric around Seven “Bare” AGNs Using X-Ray Reflection Spectroscopy. Astrophysical Journal, 874 (2). Art. No. 135. ISSN 1538-4357. doi:10.3847/1538-4357/ab0a00.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present the study of a sample of seven "bare" active galactic nuclei observed with Suzaku. We interpret the spectrum of these sources with a relativistic reflection component and we employ our model relxill_nk to test the Kerr nature of their supermassive black holes. We constrain the Johannsen deformation parameters α_(13) and α_(22), in which the Kerr metric is recovered when α_(13) = α_(22) = 0. All our measurements are consistent with the hypothesis that the spacetime geometry around these supermassive objects is described by the Kerr solution. For some sources, we obtain quite strong constraints on α_(13) and α_(22) when compared to those found in our previous studies. We discuss the systematic uncertainties in our tests and the implications of our results.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Tripathi, Ashutosh0000-0002-3960-5870
Bambi, Cosimo0000-0002-3180-9502
Dauser, Thomas0000-0003-4583-9048
García, Javier A.0000-0003-3828-2448
Jiang, Jiachen0000-0002-9639-4352
Additional Information:© 2019. The American Astronomical Society. Received 2019 January 12; revised 2019 February 15; accepted 2019 February 23; published 2019 April 1. This work was supported by the National Natural Science Foundation of China (NSFC), grant No. U1531117, and Fudan University, grant No. IDH1512060. A.T. also acknowledges support from the China Scholarship Council (CSC), grant No. 2016GXZR89. A.B.A. also acknowledges the support from the Shanghai Government Scholarship (SGS). J.A.G. acknowledges support from the Alexander von Humboldt Foundation. J.J. is supported by the Cambridge Trust and the Chinese Scholarship Council Joint Scholarship Programme (201604100032). S.N. acknowledges support from the Excellence Initiative at Eberhard-Karls Universität Tübingen.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
National Natural Science Foundation of ChinaU1531117
Fudan UniversityIDH1512060
China Scholarship Council2016GXZR89
Shanghai Government ScholarshipUNSPECIFIED
Alexander von Humboldt FoundationUNSPECIFIED
China Scholarship Council201604100032
Cambridge TrustUNSPECIFIED
Eberhard-Karls Universität TübingenUNSPECIFIED
Subject Keywords:accretion, accretion disks; black hole physics; gravitation
Issue or Number:2
Record Number:CaltechAUTHORS:20190401-084307071
Persistent URL:
Official Citation:Ashutosh Tripathi et al 2019 ApJ 874 135
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:94308
Deposited By: George Porter
Deposited On:01 Apr 2019 16:37
Last Modified:16 Nov 2021 17:04

Repository Staff Only: item control page