2MAPPS Software Interface Specification DBM09 4.0 99/04/22 Interface Name: DBMAN/DB Scan Data Interface Type of Interface: Database (Informix) Field Data Specification Written By: DBMAN _______________________________ R. Cutri Read By: Informix DB Description: This SIS describes the subset of columns from the "scan_dat" tables that will comprise the "scan_dat" tables to be released publically with the incremental 2MASS data releases. All columns shown here can be found in the full "scan_dat" tables that accompany the ops working and release working databases. There are no derived fields in this table. This data belongs to a group of data labelled the "scan DB" for convenience, to separate it from the extracted source list data labelled the "source DB". There are 4 different "scopes" of the data in the "scan DB": tile, night/ hemisphere, scan, and coadd. Except for tile and night/hemisphere (hereafter called simply "night"), each scope is a subset of the one preceeding it; for example, there are up to 999 scans per night, with x coadds for each scan, etc. Additionally, much of the night data, mainly calibration data, have duplicate fields for each band. The entire sky is covered by overlapping strips called "tiles", which define the strips to be scanned in the survey. Thus each scan belongs to exactly one tile, but each tile may be scanned more than once, usually on different nights, until data having acceptable quality is taken. If a field is not applicable or contains a "bad or N/A measurement value" (see previous 2MAPPS SISs for details) for a certain entry, the field will contain "NULL" values as defined by the DB. The descriptions below contain the following information: 1. "Name" contains the names of the DB fields or table columns. Note that they are all in lower case, because the DB doesn't distinguish between upper and lower case names. If there is a number in parentheses after the name, please refer to the numbered notes at the end of the descriptions for more information. Some fields are repeated 4 times, once for each corner, but are found only once in the description below; these fields contain "<#>" in the name, where "#" ranges from 1 to 4. In addition, some fields are repeated 3 times, once for each band, but are found only once in the description below; these fields contain "" in the name, where "b" is understood to mean "j", "h", and "k". NOTE: The "cntr" column MUST be the first column in each table. 2. "Description" contains short descriptions of the field contents. 3. "Units" contains the units of the values in the fields. 4. "DBType" contains the DB data storage types for the fields. Note that some data types are further defined by values in parentheses following the type name. Also, these types are NOT cast in stone and could change. 5. "Null" indicates (y/n) whether the DB fields accept NULL values. 6. "Idx" contains a code indicating whether fields are indexed and what type of indexes they have. If the code is "0", the field is not indexed. If it is "1", the field has a simple index. If there is a "u" after the digit(s), the index is a "unique" one. If the code has a 2-digit number, the first digit indicates to which composite index the field belongs, and the second digit indicates the ordering of the fields within the composite index. If the code has a 3-digit number, the field will have both a simple and composite index. 7. "Fmt" contains a C-like description of the best formats for displaying the field contents, *excluding* a leading space for field separation. 8. "Tbl" contains the (sub-)table ID to which the fields belong. NOTE: The "cntr" field will be the first field in each sub-table, and is used as a join index. The 1st sub-table ("01") is the "main" sub-table, and must contain one entry per table cntr number; any other sub-table will not contain an entry for a cntr number if its fields would all be NULL. 9. "Min", "Sho", and "Std" indicate (y/n) whether the DB fields are found in the "mini", "short", and "standard" table output views. NOTE: A line beginning with "-------" can only be used herein to delineate the section of field/data dictionary lines seen below. Name Description Units DBType Null Idx Fmt Tbl Min Sho Std ---------------------------------------------------------------------------------------------------------------------------------------------- cntr entry counter (key) number (unique within table) - integer n 1u 6d 01 n n n hemis hemisphere (N/S) of observation - char(1) n 21u 1s 01 y y y date observation date - date n 22u yymmdd 01 y y y scan scan number (unique within date) - smallint n 23u 3hd 01 y y y tile_id tile ID number - integer n 1 5d 01 n n y ra right ascension (J2000 decimal deg) of scan center deg decimal(9,6) n 1 10.6f 01 y y y dec declination (J2000 decimal deg) of scan center deg decimal(8,6) n 1 10.6f 01 y y y glon galactic longitude (decimal deg) of scan center deg decimal(9,6) n 1 10.6f 01 n n y glat galactic latitude (decimal deg) of scan center deg decimal(9,6) n 1 10.6f 01 n n y x unit sphere x value of scan center - decimal(17,16) n 0 19.16f 01 n n n y unit sphere y value of scan center - decimal(17,16) n 0 19.16f 01 n n n z unit sphere z value of scan center - decimal(17,16) n 0 19.16f 01 n n n ra_<#> (1) right ascension (J2000 decimal deg) of scan corner <#> deg decimal(9,6) n 0 10.6f 01 n n y dec_<#> (1) declination (J2000 decimal deg) of corner <#> deg decimal(8,6) n 0 10.6f 01 n n y quality quality score for scan (0-10) - smallint n 1 2hd 01 y y y ut_beg beginning UT of scan data time datetime(h-s) n 0 %H:%M:%S 01 n n y julut_beg Julian date beginning UT of scan data jdate decimal(9,4) n 0 10.5f 01 n n y ut_end ending UT of scan data time datetime(h-s) n 0 %H:%M:%S 01 n n n julut_end Julian date ending UT of scan data jdate decimal(9,4) n 0 10.5f 01 n n n _zp band photometric zero-point for scan mag decimal(5,4) n 1 7.4f 01 y y y _zperr band rms error from zero-point mag decimal(5,4) n 1 7.4f 01 y y y _r1_norm band Read1 mag normalization value mag decimal(5,4) n 1 7.4f 01 n n y _r1_norm_rms band rms of Read1 mag normalization value mag decimal(5,4) n 1 7.4f 01 n n y _pts_noise log10 of band modal point src noise estimate logmJy decimal(6,4) y 1 7.4f 01 y y y _snr10 (3) No. of detections in scan with instrumental SNR>10 - integer n 0 6d 01 n n y n_ext (4) No. of extended sources detected in scan - integer n 0 6d 01 n n y night_key (2) key to night data record - integer n 1 4d 01 n n n spt_ind spatial (x,y,z) index key - integer n 1 9d 01 n n n ---------------------------------------------------------------------------------------------------------------------------------------------- total # columns = 46, # bytes/row = 1270 ---------------------------------------------------------------------------------------------------------------------------------------------- NOTES: (1) The four ra_[1234] and dec_[1234] fields contain the RA and Dec positions of the four corners of the fully-covered area of the scan (i.e. the area covered by all three bands). The corners are numbered as follows:
1: eastern corner at scan start
2: western corner at scan start
3: eastern corner at scan end
4: western corner at scan end
------------------------- (2) This field is set to the key of the record containing the corresponding night data in the night data table. The records will also have the same date and hemisphere keys. ------------------------- (3) This fields contains the number of raw point sources detections made in the scan during initial processing that have instrumental magnitudes of J<15.8, H<15.1 or Ks<14.3 at. This source count is a diagnostic measure of the characteristic density of the region, but is not necessarily equal to the number of sources of this brightness that can be found in this scan in the Point Source Catalog. ------------------------- (4) This fields contains the number of extended source candidates made in the scan during initial processing. This source count is a diagnostic measure of the characteristic density of the region, but is not necessarily equal to the number of sources of this brightness that can be found in this scan in the Extended Source Catalog. ----------------------------------------------------------------------------------------------------------------------------------------------