Revised NICMOS Instrument Science Report 99-007 " /> NICMOS STScI Analysis Newsletter 21
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NICMOS STScI Analysis Newsletter 21

NICMOS STScI Analysis Newsletter 21

December 1999

CONTENTS:


        - NICMOS NEWS
          + New "NICMOS Data Handbook" is now available 
	  + Revised NICMOS Instrument Science Report 99-007

        - RECENT PREPRINTS

        - APPENDIX:  NICMOS CONTACTS

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				NICMOS NEWS
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New "NICMOS Data Handbook" is now available
-------------------------------------------

We are pleased to announce the release of the new NICMOS Data Handbook,
your one-stop shopping guide to understanding, reducing and analyzing 
NICMOS data.  The new NICMOS Data Handbook is a spin-off from the venerable 
HST Data Handbook.  In previous editions, the HST Data Handbook provided 
material covering all HST Instruments, past and present.  Most of the 
material in the NICMOS chapters of the old HST Data Handbook (version 3.0, 
with NICMOS update 3.1) dates from before the launch of the instrument or 
from early in its operational lifetime, and thus has fallen quite out of date.
In order to simplify and speed the process of distributing updated information 
on NICMOS, we have now created a separate NICMOS Data Handbook as a stand-alone 
document.  

Our understanding of NICMOS and its data products has grown considerably 
during the past year and a half.  The NICMOS Data Handbook is an attempt
to gather and distribute as much updated, practical information as possible 
about NICMOS data, its properties and foibles, and about the techniques and
software available for reducing and analyzing it.    The Handbook is organized
in five chapters:

  1.  Instrument Overview:   a brief introduction to the instrument, its
	readout modes, and terminology;

  2.  Data Structures:  a description of the contents of NICMOS images,
	data formats, and header keywords;

  3.  Calibration:  an overview of the standard calibration pipeline procedures
	and software, particularly the STSDAS tasks calnica and calnicb;

  4.  Anomalies and Error Sources:  an illustrated guide to anomalies and 
	problems which can affect NICMOS data, with discussions of various
	techniques and software for eliminating or minimizing the effects 
	of these phenomena;

  5.  Data Analysis:  a collection of useful information to aid in the
	analysis of various sorts of NICMOS data, including discussions
	of photometric calibration, pixel scales and geometric distortion,
	PSF subtraction, coronagraphic data reduction, polarimetry, and
	NICMOS grism spectroscopy.

All five chapters are updated from the material previously available in
the HST Data Handbook, but Chapters 4 and 5 in particular have the most
extensive new information, and will probably be of greatest interest to
those reducing and analyzing GO and Archival NICMOS data.  Chapter 4 
collects a wide variety of information on practical techniques for 
recognizing, understanding, and handling common NICMOS data anomalies 
such as shading, floating quadrant bias or "pedestal," image persistence, 
etc., and may help you to achieve higher quality reductions of your NICMOS 
data.  Chapter 5 collects useful information on new NICMOS software tools 
(e.g., new STSDAS tasks and the WWW-based NICMOS History Tool), updated 
material on NICMOS photometric calibration. pixel scales and geometric 
distortion, and practical advice and software for analyzing special NICMOS 
modes such as coronagraphy, polarimetry and grism spectroscopy.

The NICMOS Data Handbook is now available on line in PDF format,
and can be downloaded either as a single document and as separate 
chapters.     From the STScI NICMOS pages,

     http://www.stsci.edu/instruments/nicmos/topnicmos.html

click on "Documentation" and then follow the link to the NICMOS 
Data Handbook (Version 4.0, December 1999).   An HTML version of
the Handbook will be posted sometime in the near future.


Revised NICMOS Instrument Science Report 99-007
-----------------------------------------------

NICMOS Instrument Science Report 99-007, "NICMOS Growth Curves"
(S. T. Holfeltz & D. Calzetti) has been revised. The revised version
is available via the www at URL
	http://www.stsci.edu/instruments/nicmos/nicmos_doc.html

  Instrument Science Report NICMOS 99-007: NIC 2 Growth Curves
  ------------------------------------------------------------
  	S. T. Holfeltz & D. Calzetti, December 22, 1999 

Abstract

The Encircled Energy for isolated stars has been analyzed for NIC 2 F110W, F160W
and F165M to quantify both spatial and temporal variations in the growth curve.
The typical variation observed is less than 4% at 3 pixels distance from the PSF
peak for calibration data and less than 2% beyond radii of 3 pixels for science
data which targeted isolated stars; science datasets of sparse fields with
targets which are not isolated, instead, show variations up to 16%.  Between 1.5
and 6.5 pixels, the Encircled Energy rises by about 42%.  This value is
consistent with information published in the NICMOS Instrument Handbook.


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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.

LEHAR, J.; FALCO, E.E.; KOCHANEK, C.S.; MCLEOD,
B.A.; MUNOZ, J.A.; IMPEY, C.D.; RIX, H.-W.; KEETON,
C.R.; PENG, C.Y. "HST Observations of 10 Two-Image
Gravitational Lenses" ApJ

MARCONI, A.; SCHREIER, E.; KOEKEMOER, A.; CAPETTI,
A.; AXON, D.; MACCHETTO, D.; CAON, N. "Unveiling
the Active Nucleus of Centaurus A" ApJ accepted

NOLL, K.S.; LUU, J.; GILMORE, D. "Spectroscopy of
Four Kuiper Belt Objects" AJ 2-00

PENG, C.Y.; IMPEY, C.D.; FALCO, E.A.; KOCHANEK,
C.S.; LEHAR, J.; MCLEOD, B.A.; RIX, H-M.; KEETON,
C.R.; MUNOZ, J.A. "The Quasar Pair Q1634+267A,B and
the Binary QSO Versus Dark Lens Hypothesis" ApJ
524: 572-581, 1999
http://www.journals.uchicago.edu/cgi-bin/resolve?ApJv524p572

DE MARCHI, G.; PARESCE, F.; PULONE, L. "The Mass
Function of Main Sequence Stars in NGC 6397 from
Near IR and Optical High Resolution HST
Obervations" ApJ accepted

QUILLEN, A.C.; ALONSO-HERRERO, A.; RIEKE, M.J.;
RIEKE, G.H.; RUIZ, M.; KULKARNI, V. "NICMOS Imaging
of Molecular Hydrogen Emission in Seyfert Galaxies"
ApJ accepted

WYSE, R.F.G.; GILMORE, G.; FELTZING, S.;
HOUDASHELT, M. "The Low-Mass Stellar IMF at High
Redshift: Faint Stars in the Ursa Minor Dwarf
Spheroidal Galaxy" Hy-Redshift Universe


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

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