SuperCLASS. I. The Super CLuster Assisted Shear Survey Project overview and data release 1. (2020)
Keywords :
galaxies evolution - large-scale structure of Universe - cosmology: observations - radio continuum: galaxies -
Abstract:The SuperCLuster Assisted Shear Survey (SuperCLASS) is a legacy programme using the e-MERLIN interferometric array. The aim is to observe the sky at L-band (1.4GHz) to a r.m.s. of 7uJy/beam over an area of 1 square degrees centred on the Abell 981 supercluster. The main scientific objectives of the project are: (i) to detect the effects of weak lensing in the radio in preparation for similar measurements that will be made by the Square Kilometre Array (SKA); (ii) an extinction free census of star formation and AGN activity at z up to 1. In this paper we give an overview of the project including the science goals and multi-wavelength coverage before presenting the first data release. We have analysed around 400 hours of e-MERLIN data
...(more)
Three catalogues are provided containing L-band optical and BVr'i'z'
brightness and morphological data for sources in the SuperCLASS field,
consisting of ~1 square degree in the Northern sky. Catalogues
superclass_vla_dr1 and superclass_emerlin_dr1 were created using data
from the VLA and e-MERLIN radio telescopes respectively on the 0.26
square degree DR1 region. VLA data is from 24 hours of observing over
112 pointings in A configuration in the 1-2GHz (L-band). The
correlator was configured to deliver 250kHz spectral channels (a total
of 4000) in full polarization with 1s time sampling. e-MERLIN data is
from 49 pointings over the Northern part of the same field, from
~400-hours of data taken in the frequency range 1.204-1.717GHz, with
512 spectral channels of width 125kHz and 1s time integrations. Both
sets of radio data were imaged using forms of the CLEAN algorithm. The
VLA image Gaussian restoring beam had major axis 1.9arcsec, minor
axis 1.5arcsec and position angle 80deg east of north. The e-MERLIN
Gaussian restoring beam had major axis of 0.417arcsec, minor axis
0.232 arcsec and position angle 147.93deg east of north. Sources in
VLA images were detected and had their fluxes measured using the
PyBDSF software and all output columns from this are provided, along
with morphological classifications and measurements from the IM3SHAPE
and SuperCALS pipelines described in the accompanying papers. Sources
in e-MERLIN images were detected and had their fluxes measured using
the PyBDSF software, with catalogues being the union of detections
made with three smoothing scales applied to the image (0.4, 0.6,
2.0-arcsec). The catalogue superclass_subaru_full is for the full
1.755 square degree SuperCLASS region. This contains AB magnitudes
measured from the Subaru Suprime-Cam observations of the SuperCLASS
field in BVr'i'z' bands. Sources were detected using the SExtractor
software, before having their redshifts inferred using the EAZY
software and their morphology measured with the IM3SHAPE software.
Ian Harrison, ian.harrison-2(at)manchester.ac.uk
