DLS Schema Notes
June 15, 2009

 

Updated: October 10, 2009

Updated: December 7, 2009
Updated: June 17, 2010

 



PhotoObj

 

This is a table which has been added as an intersection for the various catalogs which are created by Sextractor, Colorpro, BPZ, Ellipto, etc.  It is essentially a minimal detection catalog with the most common filters already applied, plus a few fields which are often used to make catalog cuts.

 

This table uses PhotoObjAll as a base catalog, with duplicate objects, low signal-to-noise areas at the subfield boundaries, and objects around bright stars and bleeds removed.

           

 

Field

type

description

objid

bigint

Identifier of each object.  This is also the primary key of the PhotoObjAll table, and is  used as a foreign key in may other tables (Spectra, BPZ, Colorpro and many others)

alpha

delta

double

double

Position of the object in FK5 decimal coordinates.  This value is currently taken from raR, decR, but in general should represent our best measurement of the object centroid.

subfield

char(5)

Fnpmm subfield designator n = 1,5, mm = 11…33

For example, F1p11.  This is the subfield of the image which was used to extract the object, not necessarily the closest containing subfield.

cellx

integer

x position of object in cell grid, from 0 to 9

celly

integer

y position of object in cell grid, from 0 to 9

number

bigint

sextractor ordinal object number.  This number is only mapped to a given object within the context of the sextractor run.  In dual mode, number should be the same as the numbers for the BVRz runs.

cx,cy,cz

float

position of the object on the unit sphere.

htmid

bigint

numeric identifier for HTM indexing

processflags

int

See discussion under PhotoObjAll below.  Note that the objects in this table have already been cut on processflag&0x1f, so you should not apply this cut again when querying this table.

B

float

Colorpro magnitude

Berr

float

Colorpro magnitude error

V

float

Colorpro magnitude

Verr

float

Colorpro magnitude error

R

float

Colorpro magnitude

Rerr

float

Colorpro magnitude error

z

float

Colorpro magnitude

zerr

float

Colorpro magnitude error

 

 

 

 

 


PhotoObjAll

 

    This is the 1.0 sigma sextractor catalog, made by combining the R detection catalog with the dual mode catalogs produced for BVz.  The column 'subfield' indicates which dlsmake.fits catalog was used to make the measurement, not necessarily the nearest subfield center to the object.  The band (B,V,R, or z) is postfixed to the sextractor parameter name in this combined catalog to indicate from which filter the measurement came.

 

Note that this catalog contains about 10% duplicates, due to the overlap at the subfield boundaries.  Objects which are excluded in the column processflags when a duplicate object is detected in another subfield.  If duplicates are detected, the one which is closest to its subfield center is not flagged as a duplicate, and any othere have one of bits 0,1, or 2 set in processflags.  When objects near the subfield boundary are deblended differently in different subfields, it is still possible for duplicates to appear

 

field

type

description

objid

bigint

Identifier of each object.  This is the primary key of the PhotoObjAll table, and is also used as a foreign key in may other tables (Spectra, Filters, Colorpro and many others)

alpha

delta

double

double

Position of the object in FK5 decimal coordinates.  This value is currently taken from raR, decR, but in general should represent our best measurement of the object centroid.

subfield

char(5)

Fnpmm subfield designator n = 1,5, mm = 11…33

For example, F1p11.  This is the subfield of the dlsmake.fits images from which object was taken.

cellx

integer

x position of object in cell grid, from 0 to 9

celly

integer

y position of object in cell grid, from 0 to 9

number

bigint

Sextractor ordinal object number.  This number is only mapped to a given object within the context of the sextractor run.  In dual mode, number should be the same as the numbers for the BVRz runs.  If the sextractor run was on cell images, subfield+cellx+celly+number is a unique identifier, and if on subfield images, subfield+number is a unique identifier.

cx,cy,cz

float

position of the object on the unit sphere.

htmid

bigint

numeric identifier for HTM indexing

distancetoborder

float

Distance of this object from the nearest subfield border.  If positive, this object is closest to the center of its subfield.  If negative, this object is closest to a neighboring subfield.  This value is used in the de-duplication process.

distancetocelledge

float

Distance of this object to the edge of its cell.  Used for cell du-duplication.

duplicateids

varchar(50)

CSV list of objids which were identified as duplicates of this object.  An objid in this list is marked with processflag&0x7 in its own row.

processflags

int

Bitmap of states detected for this object during processing

 

bit 0

Set if this object is excluded because a duplicate exists and the replacement object is inside its border

 

bit 1,2

Set if this object is excluded because a duplicate exists and the replacement object is outside the subfield border

 

bit 3

Object is excluded by border frame.  These are objects with very few observations due to proximity to the subfield edge.

 

bit 4

Object is excluded for version 2009 exclusion regions

 

bit 5

Object is excluded by version 2006 of exclusion regions

Sextractor parameters

 

The sextractor parameters are all caps, with the band {BVRz} postpended.

 

The fields subfieldcount, duplicateid are part of a previous de-duplication scheme and are not longer in use.

 

The fields inexclusion1 through inexclusion8 are no longer being used.  They have been replaced with processflags bits.

 

The fields cx, cy, cz, and htmid are for an HTM coordinate system and are not currently in use.

 

 

Coords

 

field

type

description

subfield

CHAR(5)

String version of the subfield (e.g., F2p23)

racenter

float

Coordinates of center of subfield

deccenter

float

 

ramax

float

Maximum ra of subfield

decmax

float

Maximum dec of subfield

ramin

float

Minimum ra of subfield

decmin

float

Minimum dec of subfield

minobjid

bigint

Minimum id of an object in this subfield (should be the same as min(p.objid) from PhotoObjAll as p where p.subfield = subfield

maxobjid

bigint

Maximum id of an object in this subfield (should be the same as max(p.objid) from PhotoObjAll as p where p.subfield = subfield

 


Note that because of the tangent plane projection, the maximum and minimum coordinate values are approximate.  The closed set of points defined by these coordinate should include all the objects in the field, but may include some additional objects from bordering subfields.


Colorpro                To be defined

field

type

description

subfield

char(5)

subfield of dlsmake.fits from which this observation was taken

numberr

bigint

sextractor id number of this object from the Colorpro sextractor run

cellx

int

x coordinate of cell for this object

celly

int

y coordinate of cell for this object

alpha

float

 

delta

float

 

x

float

 

y

float

 

area

float

 

b

float

 

berr

float

 

v

float

 

verr

float

 

r

float

 

rerr

float

 

z

float

 

zerr

float

 

objid

bigint

PhotoObjAll identifier.  If this value is not defined, the object is either a duplicate or a detection which Colorpro’s sextractor run found and the main sextractor run did not

 


Bpz

field

type

description

subfield

char(5)

Subfield in which this object was detected and measured

number

bigint

sextractor id of the object within the subfield

objid

bigint

matching id to the object in PhotoObjAll

zb

float

 

z_b_min

float

 

z_b_max

float

 

t_b

float

 

odds

float

 

z_ml

float

 

t_ml

float

 

chi2

float

 

m0

float

 

 

Probslite

field

type

description

subfield

char(5)

subfield catalog from which this object was taken.  This value matches subfield in Bpz.

number

bigint

sextractor id number of this object.  This field matches the number field in Bpz

c1

 

400 probability distribution values for z = .01 to 4.0

 

 

c400

 

 

 

 

Dlsqc                  

 

field

type

description

subfield

char(5)

 

numberr

bigint

sextractor id for this subfield – R band

alpha

double

 

delta

double

 

dlsqc

float

 

dlsqc_prob

float

 

objid

bigint

PhotoObjAll object id

 

 

Ebv                     Extinction coefficients from Schlegel, et. al.

 

 

field

type

description

objid

bigint

primary key, matched to PhotoObjAll

alpha

double

 

delta

double

 

ebv

float

ebv coefficient for this pointing

 


Spectra                       Table of spectral redshifts
                              The detailed features only to UCD reduced spectra.

 

field

type

description

specid

bigint

primary key

alpha

double

ra and dec of the object, in decimal

delta

double

 

z

float

confirmed spectroscopic redshift of this object

source

varchar(32)

source of this redshift

maskname

varchar(3)

for spectra reduced internally, this indicates the Keck maskname

slit

int

number of the slit (typically 1-20 for LRES)

subslit

int

number of the object within the slit numbered oridinally, starting from the slit bottom

zstd

float

standard deviation of the z measurement, based on deviation of known features.  This value is not weighted as the errors of the individual features were not measured.

featurecnt

int

number of features used to make this measurement

rating

varchar(16)

subjective estimate of the quality of this redshift (measured A,B,C,D,F)

quality

int

 

spectype

varchar(16)

type of spectrum based on presence of emission lines

 

 

 

objid

bigint

identifier of the PhotoObjAll matching this object



Locations               Fields and DLS Cluster locations

field

type

description

location

varchar(64)

name of the location

alpha

double

ra, dec in decimal

delta

double

 

type

varchar(64)

currently includes field, subfields, and clusters

 

 

     
Regions/Masks                 Exclusion regions

 

field

type

description

alpha

double

 

delta

double

 

subfield

char(5)

 

x

float

position of region center relative to the projection information in dlsmake.fits for ‘subfield’

y

float

position of region center

radius

float

radius of excluded object measured by starbleed (annular ring where average flux fails to within 1 sigma of sky)

satarea

float

size of saturated region in contiguous pixels

r

float

R magnitude from the USNO catalog

b

float

B magnitude from the USNO catalog

dxtop

float

 

ylentop

float

 

tiptop

float

 

basetop

float

 

dx

float

 

dy

float

 

nearestobjid

int

Nearest object in PhotoObjAll

qratio

float

Ratio of the total bleed length to the radius of the circular spread around the object.  For saturated objects, this can be used to distinguish stars and galaxies

 

 

Zp                      Zeropoints

 

This table is a utility table for converting Colorpro mags.  It will probably be removed before release.  It has the “all” subfields value for each field/band from the 2009a stacks.

 

field

type

description

field

char(2)

Field name: F1, F2, F3, F4, F5

filter

char(1)

B,V,R,z

zp

float

Zero point average for this field/band

 

 

exposure                Exposure database (from dwittman)

field

type

description

dateobs

date

 

timeobs

time

 

run

varchar(16)

 

filter

varchar(16)

 

field

int

 

subfield

char(2)

 

file_name

varchar(64)

 

exptime

float

 

observatory

char(4)

 

ra

char(11)

 

decl

char(11)

 

observer

varchar(64)

 

airmass

float

 

fwhm

float

 

magzero

float

 

type

varchar(16)

 

comments

varchar(128)

 

status

varchar(16)

 

ellipto_size

float

 

     

 

Cells                         Information about 1/100th sized cells

           

field

type

description

subfield

char(5)

 

cellx

int

x cell coordinate, x = 1,10

coordinate direction as in dlsmake.fits for subfield

celly

int

y cell coordinata, y = 1,10

coordinate direction as in dlsmake.fits for subfield

fwhmb

float

B band psf fwhm measured by colorpro from bpsf.fits

fwhmv

float

V band psf fwhm measured by colorpro from vpsf.fits

fwhmr

float

R band psf fwhm measured by colorpro from rpsf.fits

fwhmz

 

z band psf fwhm measured by colorpro from zpsf.fits