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In-flight PSF calibration of the NuSTAR hard X-ray optics

An, Hongjun and Madsen, Kristin K. and Westergaard, Niels J. and Boggs, Steven E. and Christensen, Finn E. and Craig, William W. and Hailey, Charles J. and Harrison, Fiona A. and Stern, Daniel K. and Zhang, William W. (2014) In-flight PSF calibration of the NuSTAR hard X-ray optics. In: Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray. Proceedings of SPIE. No.9144. Society of Photo-Optical Instrumentation Engineers (SPIE) , Bellingham, WA, Art. No. 91441Q. ISBN 9780819496126.

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We present results of the point spread function (PSF) calibration of the hard X-ray optics of the Nuclear Spectroscopic Telescope Array (NuSTAR). Immediately post-launch, NuSTAR has observed bright point sources such as Cyg X-1, Vela X-1, and Her X-1 for the PSF calibration. We use the point source observations taken at several off-axis angles together with a ray-trace model to characterize the in-orbit angular response, and find that the ray-trace model alone does not fit the observed event distributions and applying empirical corrections to the ray-trace model improves the fit significantly. We describe the corrections applied to the ray-trace model and show that the uncertainties in the enclosed energy fraction (EEF) of the new PSF model is (approximately less than) 3% for extraction apertures of R (approximately greater than) 60″ with no significant energy dependence. We also show that the PSF of the NuSTAR optics has been stable over a period of ~300 days during its in-orbit operation.

Item Type:Book Section
Related URLs:
URLURL TypeDescription Paper
Madsen, Kristin K.0000-0003-1252-4891
Boggs, Steven E.0000-0001-9567-4224
Christensen, Finn E.0000-0001-5679-1946
Harrison, Fiona A.0000-0003-2992-8024
Stern, Daniel K.0000-0003-2686-9241
Zhang, William W.0000-0002-1426-9698
Additional Information:© 2014 SPIE. Date Published: 24 July 2014. 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 use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA).
Group:NuSTAR, Space Radiation Laboratory
Funding AgencyGrant Number
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Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory2014-43
Series Name:Proceedings of SPIE
Issue or Number:9144
Record Number:CaltechAUTHORS:20150612-100131748
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Official Citation:Hongjun An ; Kristin K. Madsen ; Niels J. Westergaard ; Steven E. Boggs ; Finn E. Christensen, et al. "In-flight PSF calibration of the NuSTAR hard X-ray optics", Proc. SPIE 9144, Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray, 91441Q (July 24, 2014); doi:10.1117/12.2055481
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:58212
Deposited By: Ruth Sustaita
Deposited On:13 Jun 2015 01:17
Last Modified:10 Nov 2021 22:01

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