IPAC 2MASS Science and Analysis Working Group Meeting #10 Minutes
IPAC 2MASS Science and Analysis Working Group Meeting #10 Minutes,
Attendees: T. Evans, L. Fullmer, D. Kirkpatrick,
C. Lonsdale, S. Terebey, S. Wheelock
- D. Kirkpatrick: continues his search of the
'92-'94 database high proper motion objects. He's working his way
round in RA and has reached about 3hr. He reports that the database
still contains lots of artifacts, despite the extensive cleanup job
that he and Chas undertook, so that it is definitely a `user-beware'
product. These are clearly non-astronomical sources, including things
Davy and Chas didn't make any attempt to get rid of class (1) or (3)
because they're hard to characterize (though easy to recognize upon
visual inspection of the coadds). The class (2) objects need further
scrutiny because of their obvious ramifications for the 1995 data. Of
course Davy's particular search technique - looking for objects with no
POSS identification at the 2MASS position - is tuned towards finding
the artifacts as well as interesting late-type stars and brown
dwarfs. Davy is flagging the spurious sources as he goes so that they
can be flagged or removed from the database at some later time.
- internal reflections from bright stars,
- residual persistence sources, and
- other optical effects at the edge of the
array when a bright star is just out of the FOV.
Davy has succeeded in finding a high proper motion candidate that is redder
in R-K (R magnitudes from the APM database) than the object found early on by
T. Chester. He has also found several objects with no POSS candidate at all,
and very red lower limits on their R-K colors. However on inspection of the
POSS plate itself, one was found to lie right in the middle of the Pleiades
nebulosity, so it loses its interest as a potential high proper motion
object. Davy will be pursuing some of his best candidates at the Palomar
200 inch telescope in December.
S. Terebey: reported progress on studying point
source profiles for bright stars. Using IDL to derive annular-averaged
profiles the SNR is significantly improved. The best fit power law to
the wings of the profiles is about r^-4.5. She's now undertaking a
survey of the literature to compare seeing profiles 2MASS data to those
of other cameras and to theories of seeing.