A deep survey of the AKARI north ecliptic pole field

Abstract

Aims. The Westerbork Radio Synthesis Telescope, WSRT, has been used to make a deep radio survey of an ∼1.7 degree 2 field coinciding with the AKARI north ecliptic pole deep field. The observations, data reduction and source count analysis are presented, along with a description of the overall scientific objectives. Methods. The survey consisted of 10 pointings, mosaiced with enough overlap to maintain a similar sensitivity across the central region that reached as low as 21 μJy beam −1 at 1.4 GHz. Results. A catalogue containing 462 sources detected with a resolution of 17.0 × 15.5 is presented. The differential source counts calculated from the WSRT data have been compared with those from the shallow VLA − NEP survey of Kollgaard et al. 1994, and show a pronounced excess for sources fainter than ∼1 mJy, consistent with the presence of a population of star forming galaxies at sub-mJy flux levels. Conclusions. The AKARI north ecliptic pole deep field is the focus of a major observing campaign conducted across the entire spectral region. The combination of these data sets, along with the deep nature of the radio observations will allow unique studies of a large range of topics including the redshift evolution of the luminosity function of radio sources, the clustering environment of radio galaxies, the nature of obscured radio-loud active galactic nuclei, and the radio/far-infrared correlation for distant galaxies. This catalogue provides the basic data set for a future series of paper dealing with source identifications, morphologies, and the associated properties of the identified radio sources.

The North Ecliptic Pole Wide survey of AKARI: a near- and mid-infrared source catalog

“…In addition to our AKARI/NEP-Wide data, high-quality optical data, NIR J and H band data, and radio data over a more limited field are available for the NEP-Wide field (Kollgaard et al 1994;Lacy et al 1995;Sedgwick et al 2009;White et al 2010). Optical data were obtained using the 3.5 m Canada-France-Hawaii Telescope (CFHT) for the inner parts and the 1.5 m telescope at Maidanak observatory in Uzbekistan for the outer parts of the NEP-Wide field as shown Fig.…”

Through the kaleidoscope: star formation the host galaxies of radio-AGN

“…We use data from the AKARI infrared space telescope (Murakami et al 2007) survey of the North Ecliptic Pole (NEP) field, covering the wavelength range from 2 to 24 microns. Ancillary multi-wavelength data come from the Westerbork Synthesis Radio Telescope (WSRT) at 1.4 GHz (White et al 2010), from the Hershel-SPIRE instrument in the far-IR (Pearson et al, in prep. ), from the CFHT in the optical and near-IR (Oi et al 2013, subm.…”

Identification of AKARI infrared sources by the Deep HSC Optical Survey: construction of a new band-merged catalogue in the North Ecliptic Pole Wide field

“…A noticeable aspect of this NEP field surveyed by AKARI is that ancillary optical data sets are abundant, supporting the identification of the infrared sources and thus enabling proper subsequent analysis (Kim et al 2012). In addition, many other surveys or follow-up observations of the NEP (but on a limited area) have been carried out from the X-ray to radio wavelengths to cover the NEP area (White et al 2010(White et al , 2017Krumpe et al 2015;Geach et al 2017;Burgarella et al 2019;Pearson et al 2019) since AKARI obtained valuable data sets (see Fig. 1).…”