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NICMOS STScI Analysis Newsletter 24

NICMOS STScI Analysis Newsletter 24

August 2000

CONTENTS:


        - NICMOS NEWS
          + NICMOS Software Task Updates in STSDAS Version 2.2

        - RECENT PREPRINTS

        - APPENDIX:  NICMOS CONTACTS

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				NICMOS NEWS
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NICMOS Software Task Updates in STSDAS Version 2.2
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	by Howard Bushouse


STSDAS version 2.2 was publically released on August 18, 2000. This
release contains changes to several NICMOS-related software tasks.

The calnicb calibration task has been upgraded to version 2.4. This new
version has been modified to include initial support for processing of
post-SAA dark image associations (to be acquired routinely when NICMOS
is reactivated after SM3b), and has also been modified to only execute
the routine that finds and flags sources in an image if the image is of
an external field (i.e. not for darks or flats).

Three tasks that had previously been hidden in the STSDAS nicmos package
are now visible:

  iterstat - iterative image statistics computation
  sampcum  - accumulate a set of Multiaccum samples
  sampdiff - difference a set of Multiaccum samples

The biaseq and pedsky tasks have both been upgraded from CL scripts to
full IRAF native tasks. In addition to increased speed, both new tasks
include additional capabilities. In particular, the pedsky task has been
modified to accept flatfielded images as input, so that it is no longer
necessary to provide pedsky with partially-processed images, and then
finish the calibration processing after running pedsky. Because of this
change to pedsky, the nicpipe task has been modified to remove the
"stage=pedsky" parameter option, as it is no longer necessary; nicpipe can
be used with "stage=final" to produce input images for pedsky.

There are also two new tasks in the nicmos package: asnexpand and pedsub.
The asnexpand task is used to add the extra columns to a NICMOS ASN table
that are normally added by calnicb to its output ASC tables. These columns
include background signal level and pixel offsets for each image in an
association. This is useful when you want to use this information as input
to calnicb, rather than having calnicb compute it. 

Pedsub is a pedestal estimation and removal task. It is similar in concept
to pedsky, but unlike pedsky it offers operational modes that do not require
regions of blank sky in an image. It also includes an optional routine to
match the DC background levels in the four image quadrants.

Please see the STSDAS help pages for further details on all of these tasks.
Also please note that there have been some changes to the parameters of the
biaseq, nicpipe, and pedsky tasks. Users should therefore unlearn these tasks
before running the new versions.


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                         RECENT PREPRINTS
                         ----------------

We draw your attention to these papers, based on NICMOS data, that
will appear in the next few months.  This list includes all preprints 
received by the STScI Library not yet published in the journals.
Please remember to include our Library in your preprint distribution list.

SCARPA, R.; URRY, C.M.; PADOVANI, P.; CALZETTI, D.;
O'DOWD, M. "The HST Survey of BL Lacertae Objects.
IV. Infrared Imaging of Host Galaxies" ApJ 12-00

SCHULTE-LADBECK, R.E.; HOPP, U.; GREGGIO, L.;
CRONE, M.M. "A Near-Infrared Stellar Census of the
Blue Compact Dwarf Galaxies: NICOMS Detection of
Red Giant Stars in the Wolf-Rayet Galaxy Mrk 178"
AJ 10-00

WILSON, A.S.; SHOPBELL, P.L.; SIMPSON, C.;
STORCHI-BERGMANN, T.; BARBOSA, F.K.B.; WARD, M.J.
"Hubble Space Telescope Imaging of the Circinus
Galaxy" AJ 9-00

DOWNES, R.A.; DUERBECK, H.W. "Optical Imaging of
Nova Shells and the Maximum Magnitude-Rate of
Decline Relationship" AJ 10-00

MARTIN, E.L.; BRANDNER, W.; BOUVIER, J.; LUHMAN,
K.L.; STAUFFER, J.; BASRI, G. "Membership and
Multiplicity Among Very Low-Mass Stars and Brown
Dwarfs in the Pleiades Cluster" ApJ 11-00

NAJITA, J.R.; TIEDE, G.P.; CARR, J.S. "From Stars
to Super-Planets: the Low-Mass IMF in the Young
Cluster IC348" ApJ 10-00


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                     APPENDIX: NICMOS Contacts
                     -------------------------

Analysis, STSDAS or any other HST-related questions can be
addressed to help@stsci.edu.