Page History

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The program devoted 140 orbits to each cluster/blank field pair, achieving AB ≈ 28.7-29 mag optical (ACS) and NIR (WFC3) imaging with 840 orbits. Limiting AB mags are for 5-sigma detections of a point source within a 0.4" diameter aperture.

Cluster Name	z	Cluster		Parallel Field		HST FOV	Regions File
		RA	Dec	RA	Dec
Year 1:
Abell 2744	0.308	00:14:21.2	-30:23:50.1	00:13:53.6	-30:22:54.3

Image Removed

Image Added	regions
MACSJ0416.1-2403	0.396	04:16:08.9	-24:04:28.7	04:16:33.1	-24:06:48.7	Image Modified	regions
Year 2:
MACSJ0717.5+3745	0.545	07:17:34.0	+37:44:49.0	07:17:17.0	+37:49:47.3

Image Removed

Image Added	regions
MACSJ1149.5+2223	0.543	11:49:36.3	+22:23:58.1	11:49:40.5	+22:18:02.3	Image Modified	regions
Year 3:
Abell S1063 (RXCJ2248.7-4431)	0.348	22:48:44.4	-44:31:48.5	22:49:17.7	-44:32:43.8	Image Modified	regions
Abell 370	0.375	02:39:52.9	-01:34:36.5	02:40:13.4	-01:37:32.8	Image Modified	regions

These were selected primarily on their predicted lensing strength*, their low/moderate zodiacal and Galactic backgrounds, their observability with ALMA and Mauna Kea, and their observability with HST and Spitzer. We've also looked at their suitability for deep radio observations, and their existing multi-wavelength data observations.

(* Lensing strengths were calculated by Dan Coe, Johan Richard, and Adi Zitrin, based on pre-HFF HST data.)

The parallel blank field positions are constrained by the availability of HST guide stars, which permit > 30-day windows of fixed roll-angle observations with both ACS and WFC3 at both the cluster and blank field positions. From the available locations, the final parallel field location was based primarily upon the ability to obtain very deep, high quality imaging in both HST and Spitzer. Therefore the avoidance of bright stars which would cause scattered light, saturated columns, and persistence took precedence over the avoidance of extended cluster structures.

Image Modified

Frontier Fields Locations

Cluster Candidate List