OBSERVATION_UNIT Observation unit characteristics.

Name

Format

Units

Measure

Comments

Columns

Key

TIME

Double s EPOCH Time interval mid-point

INTERVAL

Double s Time interval

Data description

NUM_LINES

Int Number of spectral lines Nli

NUM_STOKES

Int Number of stokes parameters Nsto

NUM_EPOCH

Int Number of epochs Ne for provided fluxes

NUM_SCHEDBLOCK

Int Number scheduling blocks NSB for this observation unit

NUM_XBINTENT

Int Corresponding number of selected EXECUTE intents

NUM_SCANINTENT

Int Number of selected SCAN intents

Data

SOURCE_NAME

Int Name of the selected source

TRANSITION

Int( Nli) The Nli selected transition(s)

TIME_RANGE

Double(2, Ne) s EPOCH The NeTIME_RANGEs

DATA_DESCRIPTION_ID

Int The selected data description identifier

CORR_TYPE

Int( Nsto) Polarization of correlation

OBS_PROJECT_SET

String(*) Set of selected ObsProject(s)

SCHEDULE_ID_ARRAY

Int Collection (type array) of SCHEDULE_IDidentifiers

SB_ASSOC_NATURE

String Nature of the association of SBs

SCHEDULE_ID

Int( NSB) SCHEDULE_ID

XB_INTENT_ARRAY

String( NXBint) Collection (array) of XB intents

SCAN_INTENT_ARRAY

String( Nscan_intent) Collection (array) of SCAN intents

SCAN_ASSOC_NATURE

String Nature of the association of scans

ASSOC_OBS_UNIT

Int List of associated Observation Units

OBS_UNIT_ASSOC_NATURE

String Nature for the ASSOC_OBS_UNITassociation

STANDARD_MODE_ID

Int Standard mode identifier

PROCESSING_METHOD

String Processing method

PROCESSING_VERSION

Float Processing method version

PROCESSING_EXECUTE

String Processing script actually executed

PROCESSING_DATE

String Date of the processing

PROCESSING_HISTORY

String Processing log

Notes: This table defines Observation-Units and provides informations to process them. The instance of an Observation-Unit is a tuple which associates all data, or a subset of them, this association having its own logic as defined by the PI or the author who builds the data-set. The association is valid only if it satisfies a standard mode such that it can be processed.
The selection of data in the data-set to define the association is obtained by a set of filters, in the science target space or according to the logic in the Observing Programmes (project structures) or with these two types of filters together. At least one amongst these filters is mandatory.
The atomic constituent in an Observation-Unit instance is a SCAN.
An Observation-Unit includes all the required internal dependencies for the processing. The sequence of ExecuteBlocks in the EXECUTE_SUMMARY table defines the data-set. The order in that sequence is independent of the processing. For example it may be driven by the observations themselves which would depend of experimental conditions such as weather conditions. In contrast the sequence of associated data in this OBSERVATION_UNIT table is driven with a goal to achieve a scientific result from pipeline processing.
Note that the items for the processing are mandatory.
OBS_PROJECT_SET
Set of ObsProject identification(s).
TIME
Time mid-point. The same reference used for the TIME column in the MAIN table must be used. N.B.: this may concern more than one pair of EXECUTE_SUMMARY MAIN table if this OBSERVATION_UNIT gathers data from different ObsProject (case of a virtual project).
INTERVAL
Time interval.
N.B.: TIME with INTERVAL plays the role of a first filter to select a subset of data within a project. If the time range includes the start time if the first XB and the end time of the last XB and with NUM_SCHEDBLOCK=0 and or NUM_XBINTENT=0 and or NUM_SCANINTENT=0. the full ObsProject is considered for provessing.
TIME with INTERVAL may be set to select data from different ObsProjects in case of virtual projects.
NUM_LINES
Number of selected spectral line transitions Nli.
NUM_SCHEDBLOCK
If NUM_SCHEDBLOCK= 0 all the Scheduling Blocks with all their EXECUTE_ID identifiers are considered. These EXECUTE_IDmust have been indexed in the EXECUTE_SUMMARY table.
NUM_XBINTENT
If NUM_XBINTENT=0 then the full list of EXECUTE_ID will be used.
NUM_SCANINTENT
If NUM_SCANINTENT=0 then all the scans executed will be considered. If in addition NUM_XBINTENT>0 then only the ensemble of the scans for this (these) XBs are selected.
SOURCE_NAME
Source name, as specified for the observations
TRANSITION
Name(s) for the Nli transition(s)
TIME_RANGE
The Ne time range(s). Used e.g. for science studies for source time variabilities. The output image has in this case its last axis of type TIME and size Ne.
DATA_DESCRIPTION_ID
Data description identifier.
CORR_TYPE
An integer for each correlation product indicating the Stokes type as defined in the Stokes class enumeration. The size of the STOKES axis of the output image(s) corresponds to Nsto.
SCHEDULE_ID_ARRAY
Collection of scheduling blocks. The order in this array may indicate a dependency the last in the array depending to the previous one.
SB_ASSOC_NATURE
String to defining the nature of the association of Scheduling Blocks. Example: multi antenna-configuration
EXECUTE_ID_ARRAY
Collection of ExecutingBlocks identified by their identifiers i.e. their row number in the EXECUTE_SUMMARY table. The order in this array may indicate a dependency.
XB_INTENT_ARRAY
EXECUTE intent(s) selected if not all XBs required. If this item is empty then all the ExecutionBloks are considered.
SCAN_INTENT_ARRAY
SCAN intent(s) selected whithin the XBs. The order in the list may provide dependency within a Scheduling Block.
SCAN_ASSOC_NATURE
Nature of that association of scans. This can be used e.g. to proccess the data on a restricted region in the target space (sky and or spectral regions).
ASSOC_OBS_UNIT
List of associated Observation-Units in case of recursivity. It defines the union of observing units identifiers to be processed. The order in the list offers the possibility to indicate dependencies (same rule as in Makefiles). Example: begin by processing a set of scans on a source used for phase-referencing and then process the interleaved scans for the main target, applying interpolated results obtained from the first set of scans processed.
OBS_UNIT_ASSOC_NATURE
Nature of the association of the observation units. With the example given in the description of the ASSOC_OBS_UNIT item, the nature would be “Phase referencing”.
STANDARD_MODE_ID
Standard processing mode to use. Selected by the user with the observation preparation tool (TBD).
PROCESSING_METHOD
Processing method (name of the processing script) The method could be a list of successive categorized methods (TBD)
PROCESSING_VERSION
Version for that method.
PROCESSING_EXECUTE
Link the the script actually used.
PROCESSING_DATE
Date of the processing.
PROCESSING_HISTORY
History of the processing.