Data model: photoPM

General description: Recalculated proper motions using the methods of Munn et al. 2004, AJ, 127, 5, 3034-3042. Munn et al. recalibrate USNO-B positions using SDSS galaxies, and recompute proper motions including both the USNO-B and SDSS positions. Statistical errors in the USNO-B proper motions are decreased by roughly 20%-30%, systematic errors are greatly reduced, and the proper motions are placed on an absolute reference frame. Requiring a match to an SDSS object removes the large number of false high proper motion objects in USNO-B. The resultant catalog is 90% complete to g < 19.7, with statistical errors in the component proper motions of roughly 3-3.5 mas/yr, substantially smaller systematic errors, and a contamination rate of less than 0.5%. Identification information for the SDSS source is given.

Naming convention: photoPM-RUN6-CAMCOL-FIELD4.fits

Approximate size: 20 kbytes.

File type: FITS

Read by products: sas

Written by products: photoop

Required header keywords:

• P_RESOLV (string): path for PHOTO_RESOLVE variable
• P_CALIB (string): path for PHOTO_CALIB variable

Required column names:

• run (int32): Run number
• camcol (int32): Camera column
• field (int32): Field number
• id (int32): The object id within a field. Usually changes between reruns of the same field
• rerun (string): Rerun number
• objID (string): Unique SDSS identifier composed from [skyVersion,rerun,run,camcol,field,obj].
• ra (float64): J2000 Right Ascension (r-band) (deg)
• dec (float64): J2000 Declination (r-band) (deg)
• pm_objc_type (int32): type of object in SDSS (3 = galaxy, 6 = star)
• pm_match (int32): Number of objects in USNO-B which matched this object within a 1 arcsec radius (using USNO-B proper motions to do match). If negative, then the nearest matching USNO-B object itself matched more than 1 SDSS object.
• pm_delta (float32): Distance between this object and the nearest matching USNO-B object. (arcsec)
• pmL (float32): Proper motion in galactic longitude. (mas/year)
• pmB (float32): Proper motion in galactic latitude. (mas/year)
• pmRa (float32): Proper motion in right ascension. (mas/year)
• pmDec (float32): Proper motion in declination. (mas/year)
• pmRaErr (float32): Error in proper motion in right ascension. (mas/year)
• pmDecErr (float32): Error in proper motion in declination. (mas/year)
• pm_sigra (float32): RMS residual for the proper motion fit in r.a. (mas)
• pm_sigdec (float32): RMS residual for the proper motion fit in dec. (mas)
• pm_nfit (int32): Number of detections used in the fit including the SDSS detection (thus, the number of plates the object was detected on in USNO-B plus one).
• pm_usnomag[5] (float32): Recalibrated USNO-B OEJFN magnitudes, recalibrated to SDSS grgri (mag)
• pm_dist20 (float32): Distance to the nearest neighbor with g < 20 (arcsec)
• pm_dist22 (float32): Distance to the nearest neighbor with g < 22 (arcsec)