Intensive Monitoring Survey
Seven tiles at the south ecliptic pole, observed every available night with the full medium-band set.
What this survey is for
Catch variability within a single night, and build the deepest photometry 7DS will produce.
Some sources vary faster than a wide survey can follow. IMS reduces area to about 8.5 deg² — seven tiles — in order to observe every available night, which is what is required to characterize short-period variables, active galactic nuclei on short timescales, and transients appearing within the field. Observing the same tiles nightly for five years also coadds to the deepest photometry the survey will produce, about 23.6 mag at peak sensitivity. The field position was chosen to overlap the SPHEREx Deep Field South, so that 7DT optical medium-band photometry and SPHEREx near-infrared spectrophotometry cover the same volume.
Depth and cadence over area
| Area | 8.5 deg² |
|---|---|
| Field | AKARI / SPHEREx Deep Field South |
| Field center | RA 05h13m07.4s, Dec −60°28′12″ |
| Cadence | 1 day |
| Tiles | 7 |
| Time budget | 20,000 minutes per year |
| Cumulative depth | 23.6 mag over five years |
The monitored field
The 7 monitored tiles, dashed, against their neighbours on the survey tiling. Shading and the figure inside each monitored tile give the observing cycles completed on it, read from the observation database.
The field covers about 8.5 square degrees near the south ecliptic pole and is drawn at its own scale, on a tangent plane, rather than on an all-sky map where it would be a few pixels across. The whole survey footprint, with per-tile detail under the pointer and a search by position, is on the data access page.
What has been observed so far
225–276 observing cycles across 7 tiles
Progress is the median tile against a nominal five years of observable nights. Cycle counts differ between tiles because the field sets at different times through the season and because weather does not fall evenly.