Shear Measurement with Poorly Resolved Images
نویسندگان
چکیده
Weak lensing studies typically require excellent seeing conditions for the purpose of maximizing number density well-resolved galaxy images. It is interesting to ask what extent size limits usefulness astronomical images in weak lensing. In this work, we study issue with data DECam Legacy Survey (DECaLS), which a part target selection program Dark Energy Spectroscopic Instrument (DESI). Using Fourier Quad shear measurement pipeline, demonstrate that relatively poor (around 1.5 arcsec) can still yield accurate estimators. We do not find any correlation between systematic error and image resolution.
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ژورنال
عنوان ژورنال: The Astronomical Journal
سال: 2022
ISSN: ['1538-3881', '0004-6256']
DOI: https://doi.org/10.3847/1538-3881/ac84d8