Issue |
A&A
Volume 676, August 2023
Solar Orbiter First Results (Nominal Mission Phase)
|
|
---|---|---|
Article Number | A45 | |
Number of page(s) | 8 | |
Section | Astronomical instrumentation | |
DOI | https://doi.org/10.1051/0004-6361/202345979 | |
Published online | 07 August 2023 |
In-flight radiometric calibration of the Metis Visible Light channel using stars and comparison with STEREO-A/COR2 data
1
Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
e-mail: deleo@mps.mpg.de
2
University of Catania – Physics and Astronomy Department “Ettore Majorana”, Via Santa Sofia 64, 95123 Catania, Italy
3
INAF – Arcetri Astrophysical Observatory, Largo Enrico Fermi 5, 50125 Florence, Italy
4
University of Florence – Physics and Astronomy Department, Via Sansone 1, 50019 Sesto Fiorentino (FI), Italy
5
CNR – Institute for Photonics and Nanotechnologies, Via Trasea 7, 35131 Padua, Italy
6
CISAS – Center of Studies and Activities for Space “Giuseppe Colombo”, Via Venezia 15, 35131 Padua, Italy
7
INAF – Capodimonte Astronomical Observatory, Salita Moiariello 16, 80131 Naples, Italy
8
INAF – Istituto di Astrofisica Spaziale e Fisica Cosmica, Via Alfonso Corti 12, 20133 Milan, Italy
9
INAF – Turin Astrophysical Observatory, Via Osservatorio 20, 10025 Pino Torinese (TO), Italy
10
INAF – Catania Astrophysical Observatory, Via Santa Sofia 78, 95123 Catania, Italy
11
Catholic University at NASA – GSFC, Maryland, USA
12
INAF – Padua Astrophysical Observatory, Vicolo Osservatorio 5, 35122 Padua, Italy
13
University of Urbino – Dipartimento di Scienze Pure e Applicate, Via Santa Chiara 27, I-61029 Urbino, Italy
14
INFN – Istituto Nazionale di Fisica Nucleare, Section in Florence, Via G. Sansone 1, 50019 Sesto Fiorentino, Italy
15
Astronomical Institute of the Czech Academy of Sciences, Fričova 28, 25165 Ondřejov, Czech Republic
16
University of Wrocław, Center of Scientific Excellence – Solar and Stellar Activity, Kopernika 11, 51-622 Wrocław, Poland
17
INAF – Trieste Astronomical Observatory, Via G.B. Tiepolo 11, 34143 Trieste, Italy
18
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
19
Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
20
NASA Headquarters, Washington, DC 20546-0001, USA
21
University of Padova – Physics and Astronomy Department “Galileo Galilei”, Via F. Marzolo 8, 35131 Padua, Italy
22
University of Padova – Department of Information Engineering, Via Gradenigo 6/B, 35131 Padova, Italy
23
Italian Space Agency, Via del Politecnico, 00133 Rome, Italy
Received:
23
January
2023
Accepted:
24
April
2023
Context. We present the results for the in-flight radiometric calibration performed for the Visible Light (VL) channel of the Metis coronagraph on board Solar Orbiter.
Aims. The radiometric calibration is a fundamental step in building the official pipeline of the instrument, devoted to producing the calibrated data in physical units (L2 data).
Methods. To obtain the radiometric calibration factor (ϵVL), we used stellar targets transiting the Metis field of view. We derived ϵVLby determining the signal of each calibration star by means of the aperture photometry and calculating its expected flux in the Metis band pass. The analyzed data set covers the time range from the beginning of the Cruise Phase of the mission (June 2020) until March 2021.
Results. Considering the uncertainties, the estimated factor ϵVLis in a good agreement with that obtained during the on-ground calibration campaign. This implies that up to March 2021 there was no measurable reduction in the VL channel throughput. Finally, we compared the total and polarized brightness visible light images of the solar corona acquired with Metis and STEREO-A/COR2 during the November 2020 superior conjunction of these instruments. A general good agreement was obtained between the images of these instruments for both the total and polarized brightness.
Key words: Sun: corona
© The Authors 2023
Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
This article is published in open access under the Subscribe to Open model.
Open access funding provided by Max Planck Society.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.