SEL-ID Purity and completeness statistics¶

Data Product Name¶

DpdLE3IDSELIDStatistics

Data Product Custodian¶

IDSEL

Name of the Schema File¶

euc-le3-id-sel-Statistics.xsd

Last Edited for DPDD Version¶

1.1

Processing Elements Creating / Updating / Using the Product¶

Creators:

SEL_PC

Consumers:

SWG-GC

Processing function using the data product¶

LE3, SGS pipeline output product to be used by SWGs

Proposed for inclusion in EAS/SAS¶

This product is proposed for inclusion in the SAS: yes

This product is needed to query the purity and completeness statistics of the galaxy samples used for galaxy clustering analyses.

Data Product Elements¶

Header:: object of type sys:genericHeader
Data:: object of type selid:selIDStatistics
QualityFlags:: object of type selid:selStatisticsDqc
Parameters:: object of type ppr:genericKeyValueParameters

Detailed Description of the Data Product¶

This is an output data product that stores the estimates of purity and completeness for the selected Wide samples.

Observationally, we define the Halpha target sample with the following criteria applied to the Deep field catalog.

Photometric selection: H<24.
Total line flux of the Halpha complex (Halpha + [NII]) is greater than 2e-16 erg/s/cm2.
Redshift in the range 0.9 < z < 1.8.

The selected sample is constructed based on the configuration of SEL. The threshold for a correct redshift estimate is |z_{spe} - z_{true}| < 0.003. Note that there is no 1+z scaling.

Completeness is the sample completeness defined as the fraction of the selected sample that are truly part of the target sample and have a correct redshift measurement: C = \frac{N_{\rm selected, correct}{N_{\rm targets}}.

Purity is the redshift purity defined as the fraction of the selected sample that have a correct resdhift measurement: P = \frac{N_{\rm selected, correct-z}{N_{\rm selected}}.

The purity and completeness are estimated using the Euclid Deep fields, and so are strictly relevant only at the locations of the Deep fields. The purity and completeness statistics are not extrapolated over the Wide survey. The VMSP random catalog may be used to estimate purity and completeness at an arbitrary position.

Metadata¶

The metadata stored in the Data element of the XML contains useful information about the survey coverage. Here is a brief summary of the metadata:

Data/

Key	Type	Description
ConfigurationID	str	Configuration identifier
Origin	str
Version	str
PatchTileList	PatchTileList
SelectionList	Selection

The SelectionList consists of a list of one or more Selection elements, each of which contains:

Data/SelectionList/

Key	Type	Description
Completeness	float	Completeness estimate
ObjectCount	float	Number of objects used for completeness-purity estimates
Purity	float	Purity estimate
SelectionID	str	Selection identifier
SelectionName	str	Selection name
CompletenessConfInterval	Double2Type	95% confidence interval for completeness
FileContainer	DataContainer	Pointer to file
PurityConfInterval	Double2Type	95% confidence interval for purity