MAIN Data, coordinates and flags.

Name

Format

Units

Measure

Comments

Keywords

Columns

Key

TIME

Double s EPOCH Integration mid-point

CONFIG_DESCRIPTION_ID

Int Config-description identifier

FIELD_ID

Int Field identifier

Data description

SCALE_FACTOR

Float( Ncm, Nbb) Scale factor(s) for the cross and/or auto-correlations

BIT_SIZE

Int( Ncm, Nbb) Bit size(s) for the cross and/or auto-correlations

Non-key attributes

INTERVAL

Double s Time interval

EXECBLOCK_ID

Int ExecBlock identifier

SCAN_NUMBER

Int Scan number

(SUBSCAN_NUMBER)

Int Subscan number

INTEG_NUMBER

Int Integration number

STATE_ID

Int( Na) State identifier

UVW

Double(3, Na) m UVW coordinates

EXPOSURE

Double( Nbb, Na) s Effective integration time

TIME_CENTROID

Double( Nbb, Na) s EPOCH Time centroid

Data

DATA_OID

String Data object identifier

Flag information

FLAG_ANT

Int( Na) Flags concerning antennas

FLAG_POL

Int( Na, Nc) Flags concerning antennas and polarization

FLAG_BASEBAND

Int( Na, Nc, Nbb) Flags concerning antennas, polarization and basebands

FLAG_ROW

Bool The row flag

Notes: Nbb is the number of basebands (attribute of the CONFIG_DESCRIPTION table), The form of the data object is determined by the attributes of the Data description section in the CONFIG_DESCRIPTION table and by Nc, the number of correlation products, Nf, the number of frequency channels and Napc which is 1 or 2. These three sizes Nc, Nf and Napc are known via the identifiers in the DATA_DESCRIPTION_ARRAY collection.
TIME
Mid-point (not centroid) of data interval.
TIME_EXTRA_PREC
Extra time precision
CONFIG_DESCRIPTION_ID
Configuration descriptor identifier (> 0) providing a direct index into the CONFIG_DESCRIPTION sub-table row number. Note that two or more sub-arrays cannot refer to the same CONFIG_DESCRIPTION_ID identifier.
FIELD_ID
Field identifier (> 0)
SCALE_FACTOR
Scaling factors for the auto-correlated data (case Ncm= 1) or for the cross-correlated and auto-correlated data (case Ncm= 2) , this for each of the Nbb basebands, which are stored in the data cell.
BIT_SIZE
The numbers of bytes (2 or 4) for the auto-correlations (case Ncm= 1) or for the auto-correlated and cross-correlated data, this for each of the Nbb basebands, which are stored in the data cell indexed by the DATA_OIDobject identifier.
INTERVAL
Data sampling interval. This is the nominal data interval, it does not include the effects of bad data or partial integration.
EXECBLOCK_ID
This provides access to a row number in the EXECBLOCK_SUMMARY table. This meta coordinate defines the data-base in term of an implicit collection of data blocks.
SCAN_NUMBER
SCAN (ref. ALMA glossary) number. Enumeration relative to the Executing Block.
SUBSCAN_NUMBER
SUBSCAN (ref. ALMA glossary) number.
INTEG_NUMBER
INTEGRATION (ref. ALMA glossary) number. The enumeration is relative to the SUBSCAN (ref. ALMA glossary).
STATE_ID
State identifier (> 0).
UVW
Antenna-based uvw coordinates for the Na antennas. This is defined at the centroid time TIME_CENTROID .
EXPOSURE
Effective duration of an INTEGRATION (or a SUBINTEG_NUM in the STATE table is > 0).
TIME_CENTROID
Time stamp reflecting the average time the non-blanked data was integrated.
DATA_OID
Reference to the data cell object. It is an object identifier and, as such, is of type String.
FLAG_ANT
Unsigned long int (4-bytes) vector. Each bit corresponds to a specified flagging condition ( e.g. 22 = pointing, 26 = shadowing, ...). When different from zero all data concerning the antenna is affected.
FLAG_POL
Unsigned long int (4-bytes) vector . When different from zero all data concerning the polarization and antenna is invalid (all basebands) (e.g. problem incident before the down converters)
FLAG_BASEBAND
Unsigned long int (4-bytes) vector. When different from zero all data concerning the baseband and antenna is invalid (e.g. problem incident after the down converters)
FLAG_ROW
True if the entire row is flagged.


Table 1: Definition of Flags - taken from SSR
Flag Word BitCondition



FLAG_ANT 0 Last WVR calibration failed
FLAG_ANT 1 Current WVR hardware defect
FLAG_ANT 2 Last pointing calibration failed
FLAG_ANT 3 Last Temperature Scale Calibration failed
FLAG_ANT 4 Temperature Scale Calibration hardware defect
FLAG_ANT 5 Last WVR calibration failed
FLAG_ANT 6 Shadowing
FLAG_ANT 7 LO1 out of lock
FLAG_ANT 8 No correlation detected on last calibrator
FLAG_ANT 9 Too much decorrelation on last calibrator



FLAG_POL 0 Mixer not operational
FLAG_POL 1 Total power aout of range (pol)
FLAG_POL 2 LO2 out of lock
FLAG_POL 3 Integration totally blanked
FLAG_POL 4 Interference detected
FLAG_POL 7 No correlation detected on last calibrator
FLAG_POL 9 Too much decorrelation on last calibrator



FLAG_BASEBAND 0 Last Temperature Scale Calibration failed, Tsys currently estimated
FLAG_BASEBAND 1 Total power out of range
FLAG_BASEBAND 2 Interference detected
FLAG_BASEBAND 3 No correlation detected on last calibrator
FLAG_BASEBAND 9 Too much decorrelation on last calibrator
FLAG_BASEBAND 4 Integration totally blanked



 

Remarks:
  1. Sub-arrays: For a given TIME and INTERVAL the presence of different CONFIG_DESCRIPTION_ID attributes reflects different sub-arrays. With CONFIG_DESCRIPTION_ID as a key this table can have rows for different arrays, even if their are not synchronized in time. The EXECBLOCK_SUMMARY table contains an ANTENNA_ID_SET attribute which must at least include all the ANTENNA_ID referenced in the ANTENNA_ARRAY collections used in the Execution Block.
  2. Multi-configurations: In the case of data sets which includes several array configurations, note that there is a CONFIG_NAME in the EXECBLOCK_SUMMARY table; this allows to distinguish easily the case of several sub-arrays and the case of several array configurations.