The Herschel-PACS photometer calibration : Point-source flux calibration for scan maps

Balog, Zoltán and Müller, T. h. and Nielbock, M. and Altieri, B. and Klaas, U. and Blommaert, J. and Linz, H. and Lutz, D. and Moór, Attila and Billot, N. and Sauvage, M. and Okumura, K. (2014) The Herschel-PACS photometer calibration : Point-source flux calibration for scan maps. EXPERIMENTAL ASTRONOMY, 37 (2). pp. 129-160. ISSN 0922-6435

Preview

Text 1309.6099.pdf Available under License Creative Commons Attribution. Download (529kB) | Preview

Abstract

This paper provides an overview of the PACS photometer flux calibration con- cept, in particular for the principal observation mode, the scan map. The absolute flux cal- ibration is tied to the photospheric models of five fiducial stellar standards (α Boo, α Cet, α Tau, β And, γ Dra). The data processing steps to arrive at a consistent and homogeneous calibration are outlined. In the current state the relative photometric accuracy is ∼2% in all bands. Starting from the present calibration status, the characterization and correction for instrumental effects affecting the relative calibration accuracy is described and an outlook for the final achievable calibration numbers is given. After including all the correction for the instrumental effects, the relative photometric calibration accuracy (repeatability) will be as good as 0.5% in the blue and green band and 2% in the red band. This excellent calibra- tion starts to reveal possible inconsistencies between the models of the K-type and the M- type stellar calibrators. The absolute calibration accuracy is therefore mainly limited by the 5% uncertainty of the celestial standard models in all three bands. The PACS bolometer re- sponse was extremely stable over the entire Herschel mission and a single, time-independent.

Actions (login required)

Edit Item