Matching LOFAR sources across radio bands
نویسندگان
چکیده
Aims. With the recent preliminary release of LOFAR LBA Sky Survey (LoLSS), first wide-area, ultra-low frequency observations from were published. Our aim is to combine this data set with other surveys at higher frequencies study spectral properties a large sample radio sources. Methods. We present new cross-matching algorithm taking into account sizes sources and apply it LoLSS-PR, LoTSS-DR1, LoTSS-DR2 (all LOFAR), TGSS-ADR1 (GMRT), WENSS (WSRT) NVSS (VLA) catalogues. then number matched counterparts for LoLSS their properties. Results. find 22 607 (89.5%) The remaining 2 640 (10.5%) are identified either as an artefact in survey (3.6%) or flagged due closeness bright (6.9%). average index $\alpha = -0.77 \pm 0.18$ between NVSS. Between we -0.71 0.31$. flux density independent above $S_{54} 181$ mJy. Comparison slopes LoLSS--LoTSS-DR2 LoTSS-DR2--NVSS indicates that probed population exhibits evidence negative curvature.
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ژورنال
عنوان ژورنال: Astronomy and Astrophysics
سال: 2023
ISSN: ['0004-6361', '1432-0746']
DOI: https://doi.org/10.1051/0004-6361/202245669