CALPRODUCT-NP-005: NISP-P Photo-z Calibration Fields (REPLACED)

Replaced by CHAR-TARGET-002: Photo-z Calibration Fields.

Parent requirement

R-CAL-B-NP-5100
R-CAL-B-NP-5200
R-CAL-B-NP-5300
R-CAL-B-NP-5400

Time-critical

There is a trade-off between depth and area, both of which are important to have early on in the mission. The 2x2 COSMOS field must be started in the first year, and completed in the following fashion:

  1. Observe 50% of the area to 3x the depth

  2. Observe the same 50% to 5x the depth

  3. Repeat steps 1 and 2 for the remaining 50% of the area, ideally still within the first year.

At least one of the other fields shall be completed in each of the following years (starting with the second year). The 2x2 SXDS has the same completion strategy as COSMOS.

COSMOS and CDFS have priority in the first two years, since these data also fulfil CALBLOCK-F-004: Color Gradient Calibration Fields.

Dependencies

None

Objective

The purpose of these observations is to obtain NISP-P photometry in YJH bands for a sample of 20,000 galaxies with existing visible and near-infrared ground-based spectroscopy. The S/N must be 5 times better than that of the wide survey. Based on the spectroscopic reference data, the Euclid photo-z methods can be calibrated.

VIS data are needed to perform the target detection and selection in an identical manner as in the wide survey, and to help with deblending. This significantly improves the photometric redshifts. In addition, OU-MER needs VIS data to provide consistent catalogs. The minimum depth for VIS is 2x the wide survey depth. For practial and legacy purposes, all observations are conducted with the ROS, so VIS will also go to 5x the survey depth.

Fulfilled by

CALBLOCK-F-005: Photo-z Calibration Fields

Targets and pointing constraints

Table 5: Photo-z calibration fields. N_ROS refers to the number of times the ROS needs to be repeated for each pointing to reach the desired S/N, compensating for extinction and background. N_ROS is determined by EC-SURV and not imposed by calibration. CSV file

# ID

R.A.

Dec

Geometry

N_ROS

Time

COSMOS-wide

150.119

+02.21

2x2

75

358.3 h

VVDS-Deep

36.500

-04.50

1x1

58

69.3 h

CDFS

53.117

-27.81

1x1

34

40.6 h

SXDS

34.500

-05.00

2x2

58

277.1 h

Data volume

2761824 MB (624 executions of the ROS)

Processing input

Ground Processing Input Data:

Data Description:

Processing output

Updated photo-z procedures

Required accuracy, constraints

Must reach 5 times the average S/N of the wide survey.

Quality control parameters

DataModel: https://gitlab.euclid-sgs.uk/

Contact person

Calibration Lead