Observational artifacts of Nuclear Spectroscopic Telescope Array: ghost rays and stray light
| Autor: | Kristin K. Madsen, William W. Craig, Hiromasa Miyasaka, Finn Erland Christensen, Vikram Rana, K. Forster, Brian W. Grefenstette, Fiona A. Harrison |
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| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Photon
media_common.quotation_subject Physics::Optics Field of view 01 natural sciences law.invention 010309 optics Telescope Optical path Optics law 0103 physical sciences 010303 astronomy & astrophysics Instrumentation media_common Physics Spectrometer business.industry Stray light Mechanical Engineering Astrophysics::Instrumentation and Methods for Astrophysics Astronomy and Astrophysics Conical surface Electronic Optical and Magnetic Materials Satellite Space and Planetary Science Control and Systems Engineering Sky Nuclear spectroscopic telescope array business |
| Zdroj: | Madsen, K K, Christensen, F E, Craig, W W, Forster, K W, Grefenstette, B W, Harrison, F A, Miyasaka, H & Rana, V 2017, ' Observational artifacts of Nuclear Spectroscopic Telescope Array: Ghost rays and stray light ', Journal of Astronomical Telescopes, Instruments, and Systems, vol. 3, no. 4, 044003 . https://doi.org/10.1117/1.JATIS.3.4.044003 |
| Popis: | The Nuclear Spectroscopic Telescope Array (NuSTAR) launched in June 2012, flies two conical approximation Wolter-I mirrors at the end of a 10.15-m mast. The optics are coated with multilayers of Pt/C and W/Si that operate from 3 to 80 keV. Since the optical path is not shrouded, aperture stops are used to limit the field of view (FoV) from background and sources outside the FoV. However, there is still a sliver of sky (∼1.0 deg to 4.0 deg) where photons may bypass the optics altogether and fall directly on the detector array. We term these photons stray light. Additionally, there are also photons that do not undergo the focused double reflections in the optics, and we term these ghost rays. We present detailed analysis and characterization of these two components and discuss how they impact observations. Finally, we discuss how they could have been prevented and should be in future observatories. |
| Databáze: | OpenAIRE |
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