From jwf@ipac.caltech.eduTue Mar 25 09:38:45 1997
Date: Mon, 24 Mar 1997 14:57:48 -0800
From: jwf@ipac.caltech.edu
To: 2mass@ipac.caltech.edu
Cc: chas@ipac.caltech.edu, sstrom@ipac.caltech.edu,
    stiening@ipac.caltech.edu
Subject: WG Mtg #118 Minutes

           IPAC 2MASS Working Group Meeting #118 Minutes
                             3/18/97

Attendees: R. Beck, R. Cutri, T. Evans, J. Fowler, L. Fullmer,
           G. Kopan, B. Light, H. McCallon, J. White


AGENDA

1.) Position Reconstruction Biases
2.) NAMELIST Deliveries


DISCUSSION


1.) Position Reconstruction Biases

    H. McCallon described the symptoms of a bias problem in the position
reconstruction that R. Cutri had brought to his attention. In fact, two
apparently separate bias problems have been identified: one involves position
biases between Read1 and Read2-Read1 detections on the same scans, and the
other involves scan-to-overlapping-scan biases, primarily in declination.
Howard is currently investigating both of these problems.

[Note added in proof: the Read1/Read2-Read1 bias appears to have been found by
H. McCallon while following up a lead suggested by G. Kopan; the band-frame
position transformation to band-scan coordinates applied to Read1 detections
in PFPOST was applicable only to Read2-Read1 detections (an analogous
transformation routine had not yet been written for Read1 detections at the
time PFPOST was written as a temporary fill-in routine designed mostly to
allow data flow for pipeline testing), so that the Read1/Read2-Read1 offset
correction was not being applied; this is fixed in the newly delivered PFPOST.
The other bias problem is still being studied.]


2.) NAMELIST Deliveries

    Standard delivery procedure involves a difference in the way code and data
(most frequently, NAMELIST) files are delivered. Code is delivered to
rodan:/2massc/del/src/SUBSYSTEM (where "SUBSYSTEM" is the subsystem name), and
data files are delivered to rodan:/2massc/del/datan (for northern-hemisphere
data; "datan" will be replaced by "datas" for southern-hemisphere data when
this becomes appropriate).