PS1 3pi DVO Database Snapshop 2011.04.21

The latest 3pi DVO database release can be found at the following location:

rsync://ipp0032.ifa.hawaii.edu/ps1-3pi-catdirs-20110421

This rsync location is protected with a password, see your DRAVG representative for information

The following plots show the coverage in g,r,i,z,y. These plots are centered on 0,0 (ra increasing to the right). The black line is the Galactic Plane; the purple line is the Ecliptic.

filter	3pi database coverage
g
r
i
z
y

This database is similar in contents to the previous (2011/2/1) database.

Some notes on what this database contains:

• all¹ 3pi data taken since the start of demo month (2010/2/12) through the start of April (2011/4/1)
• 2MASS detections matched to all objects
• average fields for grizy and JHK (eg, avextract g i J K would work)
• zero point calibrations for the PS1 data come from the synthetic photometry database.
• astrometric calibration is the default in-line calibration relative to the 2MASS frame
• average magnitudes use a weighted mean, and skip detections that have PSF_QF < 0.85 (excessively masked objects). there is no iterative clipping, however.

¹ a caveat regarding coverage: there seem to be some gaps that do not correspond to known gaps in the data taken.

In addition, there are 4 bit flags available in the average table for each object to give a hint at quality and extendedness:

• for all PS1 detections, the detection is considered 'extended' if (mag_psf - mag_ap > 0.5)
• if the number of 'extended detections' exceeds the number of 'psf-like' detections, the object is flagged as "PS1 extended" (objflag & 0x01000000)
• if any of the detections have PSF_QF > 0.85, then the object is considered "PS1 good" (objflag & 0x04000000)
• similarly, if the 2MASS J-band flags indicate the source is extended, the object is considered "2MASS extended" (objflag & 0x02000000)
• if the 2MASS J-band detection is significant (), the source is considered "2MASS good" (objflag & 0x08000000)
  • A significant 2MASS source means their field ph_qual is one of the 3 classes A, B, or C, which means the source is > 5 sigma and has some quality limits.

For more information about 2MASS representation in DVO, see 2MASS_info_in_DVO.

Source Counts

region	N_objects_	N_detections_
n0000	238340242	859053094
n0730	229407741	859900656
n1500	215053632	892046096
n2230	212432167	904611990
n3000	204921061	842451839
n3730	170950354	711912493
n4500	154037392	698112737
n5230	130632639	652426073
n6000	92593658	461075070
n6730	57788695	234148770
n7500	34429854	113871350
n8230	9348197	27724078
s0000	249150791	902157224
s0730	265693154	1074361638
s1500	301040727	1353823003
s2230	325386490	1559497237
s3000	50808007	162899768
s3730	31141331	93423993
s4500	33001272	99003816
s5230	36304694	108914082
s6000	29756694	89270082
s6730	11730797	35192391
s7500	3734364	11203092
s8230	1026468	3079404
total	3088710421	12750159976