The scans table is part of the science data structure designed for the EVLA. each scan is attached to an execution block, and contains one or more subscans.
Definition:
Table "public.scans"
Column | Type | Collation | Nullable | Default
--------------------+-------------------+-----------+----------+----------------------------------------
scan_id | integer | | not null | nextval('scans_scan_id_seq'::regclass)
ost_scan_id | integer | | |
execution_block_id | integer | | not null |
filegroup_id | integer | | not null |
max_bandwidth | double precision | | not null |
min_bandwidth | double precision | | not null |
polarization_code | integer | | not null |
max_frequency | double precision | | not null |
min_frequency | double precision | | not null |
filename | character varying | | |
Indexes:
"scan_pk" PRIMARY KEY, btree (scan_id)
Foreign-key constraints:
"execution_blocks_scans_fk" FOREIGN KEY (execution_block_id) REFERENCES execution_blocks(execution_block_id) ON UPDATE CASCADE ON DELETE CASCADE
"filegroups_scans_fk" FOREIGN KEY (filegroup_id) REFERENCES filegroups(filegroup_id) ON UPDATE CASCADE ON DELETE CASCADE
Referenced by:
TABLE "subscans" CONSTRAINT "scans_subscans_fk" FOREIGN KEY (scan_id) REFERENCES scans(scan_id) ON UPDATE CASCADE ON DELETE CASCADE
Columns:
scan_id: an auto-generated id to uniquely identify the scan.
ost_scan_id: the san id listed in the Observation Scheduling Tool, if available.
execution_block_id: the id of the execution block that the scan is attached to. See execution_blocks table.
filegroup_id: the id of the filegroup that is attached to this scan. Depending on the telescope, this may be the same as the filegroup for the execution block, or a child of that filegroup.
max_bandwidth: the maximum bandwidth of observations in this scan.
min_bandwidth: the minimum bandwidth of observations in this scan.
polarization_code: a numeric code indicating the polarizations used in this scan. See Polarizations for details.
max_frequency: the maximum frequency of observations in this scan.
min_frequency: the minimum frequency of observations in this scan.
filename: used only in the ingestion of VLBA data from the old archive.