Embedded Files
Image credit: ESO. Acknowledgement: Aniello Grado and Luca Limatola
Goals
Goals
We use the MeerKAT telescope to observe neutral hydrogen (HI) and radio synchrotron emission in the nearby Fornax galaxy cluster (distance ~ 20 Mpc). We want to study how galaxies in Fornax evolve while they interact with one another and with the intra-cluster medium, and reveal their connection with gas in the cosmic web.
The survey consists of a mosaic of ~12 deg2 at an observing frequency of 900 to 1670 MHz. We take both spectral-line and broad-band radio continuum data out to 1.5 Mpc (projected) from the cluster centre. The survey footprint includes the centre of the cluster as well as in-falling groups to the south-west and south-east.
The MeerKAT Fornax Survey is one of the approved large survey projects that will take most of the MeerKAT observing time during the first years of its operation.
Survey Layout
Survey Layout
The small black crosses represent 91 MeerKAT pointings. The solid and dotted blue contours represent noise levels 10 percent and 40 percent higher than the minimum noise in the mosaic (0.1 mJy/beam in a 5 km/s channel with natural weighting). The solid blue contour defines a mosaic area of 11.8 deg2. The grey circles indicate galaxies listed as definite or likely cluster members in Ferguson (1980, AJ, 98, 367). The size of the circles is inversely proportional to galaxies’ B-band magnitude. The two large red crosses indicate the location of the cluster centre (NGC 1399, east) and of the south-west sub-group (NGC 1316, west). Solid, up-pointing triangles indicate Parkes HI detections by Waugh et al. (2002, MNRAS, 337, 641) down to ∼3×108 Msun. Open, down-pointings triangles indicate ATCA HI detections down to ∼5×107 Msun (PI Serra). Colours represent heliocentric velocity. The dashed magenta circle has a radius of ∼1 Mpc, ∼1.5× the virial radius.
Sensitivity
Sensitivity
Our HI cubes will have an r.m.s. noise level of 0.15 mJy/beam per 25 kHz channel at a resolution from 10 to 100 arcsec (Briggs robust = 0). The HI velocity resolution will be 1 km/s. The column density sensitivity will vary between ~1018 cm-2 and a several times 1019 cm-2 depending on resolution (at the ~20 Mpc distance of Fornax 10 arcsec ~1 kpc).
The 5 sigma HI mass sensitivity for a line-width of 25 km/s is 5×105 Msun.
Our radio continuum images will have a noise level of 2 μJy/beam. For a standard radio-to-star formation rate conversion, this corresponds to a few times 10-5 Msun/year per angular resolution element.
Report abuse