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Hubble Space Telescope
NICMOS STScI Analysis Newsletter 29

| STScI Analysis Newsletter
| April 2003
Visit the NICMOS web site
"New in the Last 45 Days" for all new information about NICMOS.

- Cycle 12 TAC Results
- Cycle 12 Phase II Proposals
- Temperature Update
- Calibration Reference Files
- High S/N Differential Spectrophotometry
- Flat Field Monitoring
- Focus Update
- Thermal Background, NICMOS + NCS
- Instrument Science Reports Since The Previous STAN:
   NICMOS ISR 2002-004: SM3b Science Flats
   NICMOS ISR 2003-001: High Signal-to-Noise, Differential
        NICMOS Spectrophotometry
   NICMOS ISR 2003-002: NICMOS Memory/Hardware Anomalies
   NICMOS ISR 2003-003: NICMOS Monitoring Stability
   NICMOS ISR 2003-004: Measuring the Cold Mask Offset
   NICMOS ISR 2003-005: NICMOS Focus Monitoring in the
        Year Following SMOV 3b
Cycle 12 Results
The HST Cycle 12 peer review panels and TAC met on
March 24-29, 2003.  A list of the approved programs can be
found on the STScI proposing web page. A total of 1,046
proposals were submitted requesting 19,674 orbits. There
are only ~3,000 orbits available in any Cycle for GO
Approximately 20% of the available orbits were awarded to
NICMOS programs, doubling the fraction of telescope time 
using NICMOS relative to Cycle 11.  A full review of the
peer review process will be presented in a forthcoming
STScI NewsLetter.
Cycle 12 Phase II Proposals
The Cycle 12 Phase II deadline is May 16, 2003. Documents
to help observers in the preparation of their Phase II
proposals are available on the STScI programs web page. A
summary of the most important documents for NICMOS programs
can be found at

Starting with Cycle 12, all observers will be required to
use the Astronomer's Proposal Tool (APT) software to
complete the Phase II process.  The older Remote Proposal
Submission-2 (RPS2) software tools will no longer be
supported.  The APT is a suite of tools, including the
Form Editor (FE), Orbit Planner (OP), the Visit Planner
(VP), the Visual Target Tuner (VTT), and the Formatted
Preview (FP).
Temperature Update

Al Schultz

During the past winter, the temperature of the NICMOS
detectors increased slowly due to small changes in the
NICMOS dewar's parasitics because of the approach of the HST
warm season.  The Earth is closer to the Sun in January than
in any other month of the year.  The total change in
temperature was on the order of, or slightly less than,
0.1 K. The temperature of the NIC1 mounting cup sensor
increased from ~77.1 K to ~77.2 K, while the Neon control
temperature remained at 72.4 K. A decrease of 0.05 K in the
NICMOS Cooling System (NCS) control-law set-point was
implemented on December 19, 2002 to maintain the detectors
baseline operating temperature of 77.1 K.  A corresponding
increase in the control-law set-point is planned to be
implemented during the HST cool season, as needed to
compensate for any variation of the detectors' temperature
relative to the baseline of 77.1 K.

Calibration Reference Files
Al Schultz, Megan Sosey, and Eddie Bergeron
NICMOS Cycle 11 calibration reference files have been
created and delivered to the HST Archive. The only
exception are the linearity reference files and the
photometric tables. These files are used by the OPUS
pipeline and by OTFR (on-the-fly-reprocessing) whenever a
data set is retrieved from the HST Archive.  The spectacular
stability of the NICMOS detectors as reported in NICMOS ISR
2003-003 indicates that the Cycle 11 flat fields are more
than adequate to provide an excellent calibration of
of NICMOS data.
A temperature-dependent synthetic dark generator is
implemented in the OPUS pipeline, OTFR, and calnica.
Detector characteristics were modeled from darks obtained
as part of the NICMOS early calibration program following

The detector pixel saturation levels component of the
linearity files for all three cameras have been updated to
reflect the change in pixel sensitivity due to operating
at the higher 77.1 K temperature.

High S/N Differential Spectrophotometry

Ron Gilliland and Santiago Arribas

Analysis of G141 grism MULTIACCUM observations of the bright
star HD 209458 (G0V, H=6.13) indicate that well planned
NICMOS observations can provide differential
spectrophotometric stability better than 1 part in 10,000 if
not even significantly better.  Grism observations were
obtained in three back-to-back orbits. Orbit-to-orbit means
in a 0.2 micron band taken in ratio to neighboring continuum,
without applying any corrections for correlated variations
in contemporaneous auxiliary parameters, differed by only
3x10^-4.  With removal of such correlated noise near Poisson
limited results seem possible. See NICMOS ISR 2003-001.

Flat Field Monitoring
Al Schultz

A review of NICMOS monthly flat field monitoring data show
that the lamp-on filter count rates (cts/sec) have remained
constant following SM3B/SMOV indicating that detector
sensitivity and the lamps fluxes have remained constant.
Additionally, pixel saturation levels have essentially
remained unchanged since SMOV. The number of grot affected
pixels has not changed since SMOV indicating stability
within the dewar.  Dithering is recommended to remove the
effects of grot.  A check of the NIC2 coronagraphic hole
image location shows hole motion similar to what was
observed during Cycle 7 and 7N. Coronagraphic observers
should tailor their observations to minimize the effects
of hole motion.  Incremental monthly and super flat field
reference files have been created and delivered to the HST
Archive for user support. See NICMOS ISR 2003-003.

Focus Update

E. Roye

Monthly monitoring of the NICMOS focus since SMOV 3b has
revealed stable and consistent focus measurements in all
three cameras. The focus values for all three cameras have
tracked consistently the current set points which were
uplinked to the telescope during SMOV 3b.  No adjustments
have been required. The current monthly focus program has
been changed to bi-monthly for NIC1 and NIC2, and to every
four months for NIC3.  As a reminder to the reader, the
NIC3 focus is beyond the adjustable range of the Pupil
Alignment Mechanism (PAM), and has been set to the default
PAM value of -9.5 mm.  We have found that the current NIC3
focus is better than it was during Cycle 7. See NICMOS
ISR 2003-005.
Thermal Background, NICMOS + NCS:

Megan Sosey

With the addition of ACS and the NICMOS Cooling System (NCS),
the aft shroud of the telescope is seeing an increased
thermal load, which warms the NICMOS fore-optics.  The
increase in temperature affects the long wavelength filters
in cameras 2 and 3, by increasing the background by ~20%. 
This change should be kept in mind by  users of these
cameras in filters longward of 2.0 microns, or in 
especially broad filters such as F175W in camera 3. Since
camera 1 has no filter with wavelengths longer than 1.9
microns, thermal emission effects in this camera are not
an issue and have not been studied. An ISR detailing this
work has been written and will soon be available to the
public. Also see NICMOS ISR 2003-004.

| NICMOS Publications                                      |
Papers published since the last STAN that report results
from new or archival NICMOS observations.

Yost, S.A. et al. 2002, "The Broadband Afterglow of GRB
  980329 ," ApJ, 577, 155-163.

Sil'chenko, O.K. et al. 2002, "Young Stellar Nuclei in
  Lenticular Galaxies: NGC 5574 and NGC 74571," ApJ, 577,

Im, M. et al. 2002,"A Hyper Extremely Red Object in the
  Field near 53W002," ApJ, 578, L19-L22.

Noriega-Crespo, A. et al. 2002, "HST NICMOS Images of the
  HH 7/11 Outflow in NGC 13331," ApJ, 580, 959-968.

Hicks, E.K.S. et al. 2002, "Star Formation in Emission-Line
  Galaxies between Redshifts of 0.8 and 1.6," ApJ, 581,

Figer, D.F. et al. 2002, ApJ, "Massive Stars in the Arches
  Cluster," ApJ, 581, :258-275.

King, N.L. et al. 2002, "A Hubble Space Telescope
  Polarization Study of Dust in the Carinae Homunculus,"
  ApJ, 581, 285-306.

Kastner, J.H. et al. 2002, "On the Asymmetries of Extended
  X-Ray Emission from Planetary Nebulae," ApJ, 581, 1225-1235.

Thompson, R.I. 2002, "Matching the Observed Star Formation
  Intensity Distribution with Empirical Laws," ApJ, 581,

  FIELDS," AJ, 125, 398-417.

  4C 39.37," AJ, 125, 1038-1052.

Alonso-Herrero, A. et al. 2003, "THE [Fe II] 1.644 MICRON
  SUPERNOVA RATE?," AJ, 125, 1210-1225.

Schneider, G. et al. 2003, "NICMOS CORONAGRAPHIC
  125, 1467-1479.

Balcells, M. et al. 2003, "Galactic Bulges from Hubble Space
  Telescope Near-Infrared Camera Multi-Object Spectrometer
  Observations: The Lack of r1/4 Bulges," ApJ, 582, L79-L82.

Smail, I. et al. 2003, "A SCUBA Galaxy in the Protocluster
  around 53W002 at z = 2.4," ApJ, 583, 551-558.

Jensen, J.B. et al. 2003, "Measuring Distances and Probing
  the Unresolved Stellar Populations of Galaxies Using
  Infrared Surface Brightness Fluctuations," ApJ, 583,

Surpi, G. and Blandford, R.D. 2003, "The Gravitational Lens
  B1608+656. I. V-, I-, and H-Band Hubble Space Telescope
  Imaging," ApJ, 584, 100-109.

Sugai, H., Davies, R.I., and Ward, M.J. 2003, "The Collimated
  Wind in NGC 253," ApJ, 584, L9-L12.

van Dokkum, P.G. and Stanford, S.A. 2003, "The Fundamental
  Plane at z = 1.27: First Calibration of the Mass Scale
  of Red Galaxies at Redshifts z > 1," ApJ, 585, 78-89.

Zirm, A.W., Dickinson, M., and Dey, A. 2003, "Massive
  Elliptical Galaxies at High Redshift: NICMOS1 Imaging
  of z~1 Radio Galaxies," ApJ, 585, 90-111.

Meakin, C.A. et al. 2003, "HST/NICMOS Near-Infrared Imaging
  of the Proto-Planetary Nebula OH 231.8+4.2," ApJ, 585,

Dickinson, M. et al. 2003, "The Evolution of the Global
  Stellar Mass Density at 0 < z < 3,' ApJ, 587, 25-40.

Rusin, D. et al. 2003, "The Evolution of a Mass-selected
  Sample of Early-Type Field Galaxies," ApJ, 587, 143-159.

Momjian, E. et al. 2003, "Very Long Baseline Array Continuum
  and H I Absorption Observations of the Ultraluminous
  Infrared Galaxy IRAS 17208-0014," ApJ, 587, 160-170.

Vijh, U.P. and Witt, A.N 2003, "The Dust in Lyman Break
 Galaxies," ApJ, 587, 533-543.

Freudling, W., Corbin, M.R., and Korista, K.T. 2003, "Iron
  Emission in z~6 QSOs," ApJ, 587, L67-L70.

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