tiles¶
Spectra, coadds, and redshifts organized per tile are under
tiles/GROUPTYPE/TILEID/GROUPID. These come in various groups (GROUPTYPE),
e.g. whether they are data from a single exposure, a single night,
all data for a given tile across all nights, or a custom combination.
Related: all data for a given patch of sky, including data grouped across overlapping tiles and coadds of targets observed on multiple tiles, are organized under the healpix directories.
GROUPTYPE can be one of:
cumulativeCoadds of all spectra on a given tile across all nights.
pernightCoadds of all spectra on a given tile in a given night.
perexpSpectra grouped by tile and then exposure.
1x_depthSelected custom subsets of exposures of deep (\(N>>1\) exposures) tiles to achieve a combined depth for each subset matching the main survey depth. That is, they are subsets of the total exposures taken for that tile, selected to achieve a specific depth, for systematics comparisons with the full depth coadds+redshifts in the cumulative group that has all exposures for each tile.
4x_depthSimilar to
1x_depth, but selected to achieve a combined depth of 4x the main survey depth.lowspeedCoadds of deep tiles using only exposures taken under poor observing conditions, for systematics checks vs. coadds using data taken under normal/good conditions. “lowspeed” refers to the rate at which S/N is accumulated.
Other custom GROUPTYPE may appear in future produtions, and not every
production will include every GROUPTYPE.
The GROUPID depends on the GROUPTYPE:
GROUPTYPE |
GROUPID |
|---|---|
cumulative |
YEARMMDD NIGHT - all data through that night |
pernight |
YEARMMDD NIGHT - only data from that night |
perexp |
EXPID - only data from that single exposure |
1x_depth |
subset number |
4x_depth |
subset number |
lowspeed |
subset number |
e.g. spectra, coadds, and
redshifts for all exposures of tile 80605 observed on 20210109 are
under tiles/pernight/80605/20210109, while all data for tile 80605
for all nights through 20210205 (including previous nights like 20210109)
are under tiles/cumulative/80605/20210205.
Subdirectories of tiles/ :