University of Sussex
Browse

File(s) not publicly available

High-Accuracy Near-infrared Imaging Polarimetry with NICMOS

journal contribution
posted on 2023-06-08, 07:31 authored by D Batcheldor, G Schneider, D C Hines, G D Schmidt, D J Axon, A Robinson, W Sparks, C Tadhunter
The findings of a nine-orbit calibration plan carried out during HST Cycle 15, to fully determine the NICMOS camera 2 (2.0 mu m) polarization calibration to high accuracy, are reported. Recently Ueta et al. and Batch-eldor et al. have suggested that NICMOS possesses a residual instrumental polarization at a level of 1.2%-1.5%. This would completely inhibit the data reduction in a number of GO programs, and hamper the ability of the instrument to perform high-accuracy polarimetry. We obtained polarimetric calibration observations of three polarimetric standards at three spacecraft roll angles separated by similar to 60 degrees. Combined with archival data, these observations were used to characterize the residual instrumental polarization in order for NICMOS to reach its full potential of accurate imaging polarimetry at p approximate to 1%. Using these data, we place an 0.6% upper limit on the instrumental polarization and calculate values of the parallel transmission coefficients that reproduce the ground-based results for the polarimetric standards. The uncertainties associated with the parallel transmission coefficients, a result of the photometric repeatability of the observations, are seen to dominate the accuracy of p and.. However, the updated coefficients do allow imaging polarimetry of targets with p approximate to 1.0% at an accuracy of +/- 0.6% and +/- 15 degrees. This work enables a new caliber of science with HST.

History

Publication status

  • Published

Journal

Publications of the Astronomical Society of the Pacific

ISSN

0004-6280

Issue

876

Volume

121

Page range

153-166

Department affiliated with

  • Physics and Astronomy Publications

Full text available

  • No

Peer reviewed?

  • Yes

Legacy Posted Date

2012-02-06

Usage metrics

    University of Sussex (Publications)

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC