Polarization Accuracy Verification of the Chromospheric LAyer SpectroPolarimeter

0562959 - ASÚ 2023 RIV NL eng J - Článek v odborném periodiku
Song, D. - Ishikawa, R. - Kano, R. - Štěpán, Jiří … celkem 28 autorů
Polarization Accuracy Verification of the Chromospheric LAyer SpectroPolarimeter.
Solar Physics. Roč. 297, č. 10 (2022), č. článku 135. ISSN 0038-0938. E-ISSN 1573-093X
Institucionální podpora: RVO:67985815
Klíčová slova: magnetic fields * chromosphere * instrumental effects
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 2.8, rok: 2022
Způsob publikování: Omezený přístup
https://doi.org/10.1007/s11207-022-02064-8

We have developed an advanced UV spectropolarimeter called Chromospheric LAyer SpectroPolarimeter (CLASP2), aimed at achieving very high accuracy measurements (<0.1% at 3 sigma) of the linear (Q/I and U/I) and circular (V/I) polarizations of the Mg II h and k lines (280 nm). CLASP2 was launched on board a NASA sounding rocket on April 11, 2019. It successfully detected the full Stokes vector in an active-region plage and in the quiet Sun near the limb across the Mg II h and k lines for the first time. To verify the polarization characteristics of CLASP2, the response matrix is estimated by combining the results obtained from the preflight calibration on the ground, with the results of the inflight calibration acquired at the solar-disk center. We find that the response matrix of CLASP2 in the Mg II h and k lines is notably close to an ideal response matrix, i.e., the scale factor and the crosstalk terms are close to 1 and 0, respectively. Moreover, the uncertainty of each Stokes parameter estimated by the repeatability of the measurements is verified to be within the required tolerance. Based on our investigation, we conclude that CLASP2 achieves 0.1% polarization accuracy at a 3 sigma level.
Trvalý link: https://hdl.handle.net/11104/0337693