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2021 Effective Area calibration of the Nuclear Spectroscopic Telescope ARray (NuSTAR)

Madsen, Kristin K. and Forster, Karl and Grefenstette, Brian and Harrison, Fiona A. and Miyasaka, Hiromasa (2021) 2021 Effective Area calibration of the Nuclear Spectroscopic Telescope ARray (NuSTAR). . (Unpublished)

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We present here the updated calibration of The Nuclear Spectroscopic Telescope ARray NuSTAR, which was performed using data on the Crab accumulated over the last 9 years in orbit. The basis for this new calibration contains over 250ks of focused Crab (imaged through the optics) and over 500ks of stray-light Crab (not imaged through optics). We measured an epoch averaged Crab spectrum of the stray-light Crab data and define a canonical Crab spectrum of Γ = 2.103 ± 0.001 and N = 9.69 ± 0.02 keV⁻¹ cm⁻² s⁻¹ at 1 keV, which we use as our calibration standard. The new calibration, released in the CALDB update 20211020, provides significant updates to: 1) the detector absorption component, 2) the detector response function, and 3) the effective area vignetting function. The calibration improves agreement between FPMA and FPMB across detectors with a standard deviation of 1.7% for repeat observations between off-axis angles of 1-4 arcmin, and the measured flux has increased by 5-15%, with 5% below 1 arcmin off-axis angle, 10% between 1-2 arcmin, and 15 above 4arcmin.

Item Type:Report or Paper (Discussion Paper)
Related URLs:
URLURL TypeDescription Paper
Madsen, Kristin K.0000-0003-1252-4891
Forster, Karl0000-0001-5800-5531
Grefenstette, Brian0000-0002-1984-2932
Harrison, Fiona A.0000-0003-2992-8024
Miyasaka, Hiromasa0000-0002-8074-4186
Alternate Title:Effective Area calibration of the Nuclear Spectroscopic Telescope ARray (NuSTAR)
Additional Information: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. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Space Science Data Center (SSDC, Italy) and the California Institute of Technology (USA). This material is based upon work supported by NASA under award number 80GSFC21M0002. We thank Murray Brightman, Renee Ludlam, Guglielmo Mastroserio, and Riley Connors for performing the case study re-analyses in §7.2.
Group:Space Radiation Laboratory, NuSTAR
Funding AgencyGrant Number
Subject Keywords:NuSTAR, X-ray, Satellite
Record Number:CaltechAUTHORS:20220113-182222694
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:112872
Deposited By: George Porter
Deposited On:13 Jan 2022 21:59
Last Modified:13 Jan 2022 21:59

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