2010
NICMOS ISR 2010-001: Finesky – removing higher order sky residuals
We report on a new IRAF task called finesky that removes higher order sky residuals in
NICMOS images by creating a masked median image of the observed sky. This median
sky image is thereafter subtracted from the science images. A residual signal after image
processing using the calibration software calnica may be present due to reference files
that do not sufficiently match the conditions of the observations. This includes a slight
mismatch in the dark current or the flat-field corrections. The task described here can
also used to create sky flat-field images.
T. Dahlen, D. Grumm
06 Jul 2010
2009
NICMOS ISR 2009-008: NICMOS Breathing and Focus Field Variations
The focus of the NICMOS cameras is monitored on a regular basis. In order to achieve
consistency in the focus determination, several effects have to be taken into consideration.
The main ones affecting NICMOS are: (1) thermally induced movement of the secondary
mirror (a.k.a. breathing), and (2) a curved focal plane for all three cameras. The latter is
known as NICMOS Focus Field Variation and affects both the measurement of the focus and
gives a position dependent Point Spread Function. In this Instrument Science Report we
discuss the breathing corrections in the context of the NICMOS Focus Monitoring Program,
and re-measure the Focus Field Variations.
T. Wiklind
06 Jul 2009
NICMOS ISR 2009-007: CalTempFromBias: Implementation and Testing
This ISR describes the CalTempFromBias program which was developed to estimate the temperature
of each of the three NICMOS detectors individually. Unlike previous NICMOS temperature
estimates, which are derived from a mounting cup sensor, these temperatures are derived
using the bias level of the detectors themselves. The uncertainty associated with these
temperature-from-bias values are 0.05K and are the basis for the new temperature-dependent
calibration products for NICMOS data. This ISR describes the program CalTempFromBias,
its options, and its applications.
N. Pirzkal
09 Jul 2009
NICMOS ISR 2009-006: NICMOS Grism Wavelength Calibration
As part of the Cycle 16 NICMOS calibration program, new observations of planetary nebulae
were obtained using all three NICMOS grisms (G096, G141, and G206). The aim of these observations
was to re-derive the dispersion relations for the grism modes of NICMOS as well as to
examine and parametrize any field dependence of the dispersion relation within the field of view
of the instrument. In this ISR, we present updated versions of the dispersion relations of the
G096, G141, and G206 grisms. While the field dependence is small (1-2% peak to peak variation),
we also compute two dimensional polynomial solutions to compute more exact dispersion
relations anywhere in the field of view of NICMOS.
N. Pirzkal
29 Jun 2009
NICMOS ISR 2009-005: NICMOS Temperature Dependent Flat-fields
The bias-derived detector temperature for all three NICMOS cameras showed a
variation of about ~2K in both the era before the installation of the NICMOS Cooling
System (NCS) 1997-1998, as well as in the post-NCS era, 2002-2008. This temperature
variation affected the detector quantum efficiency (DQE) and hence the structure of the
flat-fields. In this ISR we discuss the creation of new temperature dependent flat-field
reference files that correct for the effect of temperature on the DQE. Temperature
dependent flat-fields (*_tdf.fits) populate the keyword TDFFILE in the headers of
post-NCS data retrieved after November 19, 2008 and pre-NCS data retrieved after
January 23, 2009. The temperature dependent flat-fields are used by the FLATCORR
step in calnica version 4.4 and later. For consistency check we also created epoch
dependent flatfields
for postNCS
data and compared them with the temperature
dependent flatfields.
The result of this analysis is also included here.
D. Thatte
09 Jul 2009
NICMOS ISR-2009-004: NICMOS Photometric Calibration Pipeline
We present the details of the NICMOS Photometric Calibration Pipeline used to generate
aperture photometry. We present an overview of the different corrections employed,
explain components of the pipeline and also outline the types of photometric and
statistical data products created. In de Jong et al. (in preparation) this photometry will
be used to determine the photometric calibration constants stored in the PHOTTAB
reference files.
A. C. Viana
29 Jun 2009
NICMOS ISR 2009-003: Updates to Calnica: Using Temperature Dependent Reference Files
This report describes how the calnica data reduction software implements
temperature dependent reference files in order to correct for temperature dependent
variations in the dark current, the flat-fields, and the flux calibration. We describe in
detail the logic used by the software to decide when to apply a temperature dependent
correction and which temperature to use in that case.
T. Dahlen
29 Jun 2009
This report describes the investigation of the temperature dependence of the linear dark
and amplifier glow components of the NICMOS temperature dependent *_tdd.fits
dark reference files in the post-NCS era, 2002-2008. We find a significant temperature
dependence of the amplifier glow signal with higher counts at higher temperature when
using the bias-derived detector temperature. The linear dark should also be dependent on
temperature, however, the expected change in dark current should to be smaller than the
scatter introduced from the read noise. This is consistent with what we find. We also
describe how the calnica reduction software uses the temperature dependent dark
components when calibrating NICMOS images.
T. Dahlen
15 Jun 2009
NICMOS ISR 2009-001: New Bad Pixel Mask Reference Files for the Post-NCS Era
The last determined bad pixel masks for the three NICMOS cameras were made in
September 2002. Those masks were created using data from calibration programs
following the installation of the NCS and are therefore based on the relatively limited
data set available at the time. Since then, the NICMOS calibration monitoring programs
have regularly obtained calibration images of both flat-fields and darks, images used to
create the mask reference files. With numerous images taken during a long base-line
(2002-2008), this data set allows us to create high signal-to-noise reference files, as well
as investigate any temporal dependence of the mask files. In this ISR we describe the
creation of new mask files based on this extended data set and compare the new masks
with the previous versions. The new masks created contain a higher number of bad
pixels compared to the old versions, while the number of pixels thought to be affected by
“grot” is lower.
E. Barker, T. Dahlen
15 Jun 2009
2008
NICMOS ISR 2008-004: Summary of NICMOS SMOV4 Plans
This ISR outlines the NICMOS plan for Servicing Mission Observatory Verification 4 (SMOV4). It presents the NICMOS requirements, the planned activities to fulfill these requirements and a brief plan for the data reduction and analysis.
T. Wiklind
14 Aug 2008
NICMOS ISR 2008-003: Verifying the NICMOS Count Dependent Non-Linearity Correction
We re-investigate the NICMOS count dependent non-linearity, using the flat field lamps to
reach high count regimes. The NICMOS count dependent non-linearity has been previously
quantified and is currently corrected in NICMOS pipeline. In this document we show
that the count dependent correction is still accurate to within 1.2% of true linearity for
counts above 100 ADU independent of filter used. This is a response to the count-rate
dependent non-linearity investigations, to eliminate questions about the current count
dependent corrections.
B. Shaw, R. S. de Jong
08 Aug 2008
NICMOS ISR 2008-002: Improvements to Calnica
This ISR describes a number of improvements to calnica, the STSDAS task that
performs routine instrumental calibration of NICMOS raw images. We report two major
and a number of minor updates to the code. The major updates consist of changes in the
way the count rate is calculated from up-the-ramp fitting and changes in the cosmic rays
rejection algorithm. All updates have been extensively tested and analysis shows
improvement in the S/N of output images by 6-15% compared to the previous calnica
version. A further improvement is that the error extension in the calibrated images now
represents the true errors in a more consistent way compared to the old implementation
of the software.
T. Dahlen
06 Jun 2008
NICMOS ISR 2008-001: Bright Earth Persistence in NICMOS
We report the presence of image persistence in NICMOS data due to prior saturation of the array by the bright Earth as well as an algorithm to remove its impact. BEP (Bright
Earth Persistence) may occur when ACS and NICMOS are used in parallel, and the data
dump of ACS delays the insertion of the NICMOS filter blank as long as 6 minutes
beyond the Bright Earth avoidance angle. We have constructed a BEP frame which can
be used to model and remove the presence of BEP in NICMOS data. The algorithm is
seen to remove 99.5% of the variance in the background of BEP impacted Camera 2
data. Ongoing work involves broadening the applicability of the BEP correction to
Camera 1 and 3 and making it available as a pyraf script through STSDAS.
A. Riess, E. Bergeron
20 Mar 2008
2007
NICMOS ISR 2007-004: NICMOS Cycle 15 Baseline Calibration Plans
This document summarizes the NICMOS Calibration Plans for Cycle 15. The monitoring programs
from the previous Cycle 13 and 14 are carried out in Cycle 15. Additional calibration is
included in order to improve the accuracy of previously archived NICMOS data.
N. Pirzkal
16 Jul 2007
NICMOS ISR 2007-003: NICMOS Focus Update
This ISR will address a number of changes in the way the NICMOS focus is monitored. It
will provide a detailed explanation of those changes and a step-by-step description of
the new procedure. The ISR also highlights the results of the focus checks after the HST
safing event, which caused the NICMOS cooling system (NCS) anomalous shutdown in
February of 2007.
H. McLaughlin
29 Jun 2007
NICMOS ISR 2007-002: NICMOS Time Dependent Flat-fields
We use data obtained during the NICMOS flat-field monitoring 2002-2007 to derive a set
of time dependent flat-fields. These 'epoch' flat-fields are compared to the current
pipeline flat-fields and differences are quantified. Our results are consistent with a
decrease in DQE over the five-year period on the order of one per cent. We also find that
the spatial structure of the flat-fields change with time. The reasons for these changes are
not fully known, but we note that the changes are consistent with a change in detector
temperature with time. The order of this effect is generally less than one percent. The
'epoch' flat-fields are available on the NICMOS web page1.
T. Dahlen
29 Jun 2007
NICMOS ISR 2007-001: Removing Post-SAA Persistence in NICMOS Data
A general concern with NICMOS images is the issue of 'persistence', or residual charge
from bright sources and cosmic rays that remains trapped in pixels and is gradually
released during subsequent exposures. This is particularly noticeable after HST transits
of the South Atlantic Anomaly (SAA), where the cosmic ray rate is so high that their residual
flux contributes a significant noise component to many subsequent exposures. We
describe the 'SAAclean' task which can be run on post-SAA NICMOS images to identify
the amount of charge in each pixel that can be attributed to persistent flux from SAA cosmic
rays, and apply a correction based on an SAA persistence model to remove this flux
from the data. This task has so far been tested on a variety of NICMOS data, and this represents
the most recent update of this task in the PyRAF/STSDAS environment to the HST
observer community.
E. Barker
15 May 2007
2006
NICMOS ISR 2006-004: Temperature Monitoring of NICMOS
NICMOS observations are dependent on a cold and stable thermal environment. In this ISR we describe the temperature monitoring and how a stable thermal environment for the NICMOS detectors is achieved. A comparison between the thermal properties of the cryogenically cooled dewar during Cycle 7 and the present cooling using using the NICMOS Cooling System, is presented. A complete thermal history from the start in 1997 up to January 2006 is presented.
T. Wiklind
26 Jul 2006
NICMOS ISR 2006-003: Correcting the NICMOS count-rate dependent non-linearity
We describe a routine to correct NICMOS imaging data for the NICMOS count-rate
dependent non-linearity recently discovered by Bohlin et al. (2005) and quantified by de
Jong et al. (2006) and Bohlin et al. (2006). The routine has been implemented in the
python scripting language and is callable from the shell command line and from iraf. The
routine corrects NICMOS count-rate images assuming the non-linearity follows a powerlaw
behavior. The wavelength dependence of the non-linearity is interpolated between
the measured points of de Jong et al. (2006) and Bohlin et al. (2006) if necessary. The
count rates in the output images are modified and hence the standard NICMOS
calibration zero-points are no longer valid. New calibration zero-points have been
derived from standard star images corrected with the routine. The routine was tested on
the lamp-on/off data used in de Jong et al. (2006) to measure the non-linearity effect. We
apply the correction to the NGC1850 stellar cluster field and the Hubble Ultra Deep
Field (HUDF) to show the magnitude offsets expected due to the non-linearity on objects
with a range in luminosity and surface brightness.
R. de Jong
29 Mar 2006
NICMOS ISR 2006-002: NICMOS Count Rate Dependent Non-Linearity in G096 and G141
Since the discovery of the NICMOS count rate dependent non-linearity
documented in NICMOS ISR 2005-002, additional tests have been conducted to
further understand and quantify the effect. Long integrations of up to 25 minutes
exhibited the same level of non-linearity as the original 1-3 minute integrations.
Observations of the star P041C on high background from an internal flat field
lamp provides another measure of the wavelength dependence of the nonlinearity
to compliment the measures based on pure hydrogen WD models.
R. Bohlin
15 Feb 2006
NICMOS ISR 2006-001: NICMOS Count-rate Dependent Non-linearity Tests using Flatfield Lamps
We investigate the recently discovered NICMOS count-rate dependent non-linearity
(Bohlin et al. 2005) using the flatfield lamps to artificially increase the count rate. A star
cluster field was imaged in a lamp off-on-off sequence in all cameras in a selected set of
filters, followed by a series of darks to investigate persistence and to clean the images
from any remaining charge for the next orbit. Subtracting the lamp-off images from the
lamp-on images clearly shows residual ADUs at the star positions, indicating that a
higher background (and thus total) count rate increases the number of ADUs registered
from an object. We model the non-linearity with a power law (count-rate ЃЕ fluxѓї) and fit
this model to the data. Both NIC1 and NIC2 (NIC3 was not tested in this program) show
non-linearity, becoming stronger at shorter wavelengths, but with larger amplitude than
predicted by the Bohlin et al. NIC3 measurements. The non-linearity in NIC1 and NIC2
amounts to 0.06-0.10 mag offset per factor ten change in incident flux for the shortest
wavelength (F090M and F110W), about 0.03 mag/dex at F160W, and less at longer
wavelengths. Archival data from Cycle 7 are also analyzed, showing that the nonlinearity
has not changed in NIC2 F110W, and suggesting that this effect is independent
of detector temperature.
R. de Jong
15 Feb 2006
2005
NICMOS ISR 2005-005: NICMOS Cycles 13 and 14 Calibration Plans
This document summarizes the NICMOS Calibration Plans for Cycles 13 and 14. These
plans complement the SMOV3b, the Cycle 10 (interim), and the Cycles 11 and 12 (regular)
calibration programs executed after the installation of the NICMOS Cooling System
(NCS).. These previous programs have shown that the instrument is very stable, which has
motivated a further reduction in the frequency of the monitoring programs for Cycle 13. In
addition, for Cycle 14 some of these programs were slightly modified to account for 2
Gyro HST operations. The special calibrations on Cycle 13 were focussed on a follow up
of the spectroscopic recalibration initiated in Cycle 12. This program led to the discovery
of a possible count rate non-linearity, which has triggered a special program for Cycle 13
and a number of subsequent tests and calibrations during Cycle 14. At the time of writing
this is a very active area of research. We also briefly comment on other calibrations
defined to address other specific issues like: the autoreset test, the SPAR sequences tests,
and the low-frequency flat residual for NIC1. The calibration programs for the 2-Gyro
campaigns are not included here, since they have been described somewhere else. Further
details and updates on specific programs can be found via the NICMOS web site.
S. Arribas
02 Dec 2005
NICMOS ISR 2005-004: NICMOS Small deltaT Dewar/NCS PID Model for Orbit Night Power Reduction
Without SM4 and the installation of new Ni-HB2B batteries, HST is facing a future with
decreasing battery capacity. This ISR explores one option for reducing HST's battery
load during orbit night while maintaining the science capability of the NICMOS.
Modulating the NCS setpoint temperature, i.e., increasing it during orbit night and
decreasing it during orbit day, can accomplish this. A linear NICMOS small deltaT thermal
model was developed based on flight data serendipitously obtained during Proposal
10097, NICMOS Temperature Setpoint Darks, to predict camera one's temperature, NCS
compressor speed, and total NCS power for modulations of +/-1, +/-2, and +/-3K. The
results are presented.
T. Wheeler and M. Robinson
05 Oct 2005
NICMOS ISR 2005-003: A Test of Possible NICMOS Non-linearity
Observations of standard stars with NICMOS grism (G096), when compared with the
same standards taken by STIS (G750L), show a disagreement over the wavelength range
0.8 to 1 micron. Further comparison with ACS F850LP data confirms thisnon-linearity to
be due to NICMOS in the sense that fainter stars in NICMOS appear too faint relative to a
brighter normalisation. We investigate this over a wide magnitude range by compiling
samples of stars (over the range 8 < J < 17) and galaxies (spanning the range 17 < J <
25), with available data with both NICMOS (F110W and F160W) and ground-based JHbands.
We find no difference between the NICMOS F160W and ground-based H-band
magnitudes. However, in the case of NICMOS F110W and J-band filters, allowing for differences
in the filter response functions, we find a trend at the bright-end (J < 17), confirming
a non-linearity but smaller than that was seen in Bohlin effect by a factor of 2-3.
No significant slope is seen at the faint-end. This non-linearity is interpreted as being due
to trapping and the difference in exposure times between the bright and faint objects
(Riess 2005). We conclude that most of the observations will not be strongly affected by
this effect as the source count rates are sufficiently high so that the fraction of charge lost
to traps is negligible. The most affected observations are for faint sources with relatively
short exposures.
B. Mobasher and A. Riess
15 Aug 2005
NICMOS ISR 2005-001: NICMOS Two Gyro Mode Coronagraphic Performance
In preparation for the Hubble Space Telescope (HST) entry into Two Gyro Mode (TGM)
operations, the NICMOS coronagraphic performance was assessed during the February
21, 2005 TGM on orbit test (ID: 10448) in two filter bands (F110W and F160W). The
gyroscope pair 2-4 was used for the TGM test. Observations were obtained of a previously
observed calibration target (GJ517; sp.type=K5Ve) coronagraphically and with direct
imaging. The F110W filter performance very closely tracks the three gyro mode (ID:
10177) results. The observed jitter of ~6.2 mas had little effect on the 1.1 Лm coronagraphy.
This result clearly shows that 1.1 Лm coronagraphy is robust against the
observed TGM jitter. The NICMOS coronagraph inner working angle (IWA) is 3.2 К/D at
1.1 Лm. Consequently, there is sufficient performance compliance to target decentering of
these RMS amplitudes within the coronagraphic hole. There was a slight decline in performance
with the F160W filter with respect to three gyro mode which may be due to imaging
systematics; i.e., breathing and jitter. The 1.6 Лm coronagraphy is more susceptible to
imaging systematics primarily due its broader PSF (IWA=2.2 К/D). At r=10 pixels, the
coronagraphic diffracted and scattered light suppression factor is ~3 compared to direct
imaging, while it is a factor of 4 in three gyro mode. The observed coronagraphic performance
is essentially unaffected at 1.1 Лm with TGM operations, while there is a marginal
decline at 1.6 Лm of similar amplitude to that arising from other well-known HST/NICMOS
orbit-driven instabilities. The improvement in image contrast (and dynamic range)
with coronagraphy and TGM is still substantial over direct imaging.
G. Schneider, A. Schultz, S. Malhotra & I. Dashevsky
08 Jul 2005
NICMOS ISR 2005-002: Grism Sensitivities and Apparent Non-Linearity
Recent grism observations using the NICMOS instrument on HST have extended
the spectrophotometric wavelength coverage of a subset of 16 STIS standard
stars to ~2Лm. These observations include the three primary WD standards that
are used to establish the absolute sensitivities of the three grism modes.
However in their overlap region at 0.8-1.0Лm, the ratios of the STIS and
NICMOS fluxes for brightest/faintest stars disagree by almost 25%. ACS
spectrophotometry for two of the same stars in the same wavelength band agrees
with STIS to 2%. A comparison of the grism spectrophotometry directly with
ACS F850LP and F892N photometry for eight stars again verifies the need to
correct the NICMOS grism data for non-linearity. After correction, the NICMOS
grism fluxes have uncertainties ranging up to ~3% at 1.7Лm. The possible effect
of this newly discovered apparent non-linearity on NICMOS photometry is being
investigated with new NICMOS photometric observations and by comparisons
with independent IR data sets.
R. Bohlin, D. Lindler, & A. Riess
10 May 2005
2004
A new NICMOS ETC for imaging mode has been developed as part of the Astronomer's
Proposal Toolkit (APT) project. This new tool fully updates the NICMOS performance for
Cycles 11+, expands the funtionality of the previous ETC, providing the user more
options, and homogenizes the non-instrument specific parameters (i.e. sky background,
extinction laws) with other HST-ETCs. This report summarizes its main characteristics,
and gives some recommendations to potential users. Details about the tool itself can be
found in the documentation linked to the ETC user interface, which can be accessed from
the NICMOS web site at STScI.
S. Arribas
26 Feb 2004
NICMOS ISR 2004-001: NICMOS Coronagraphic Calibration
The NICMOS coronagraphic imaging mode has been fully reactivated following SM3B,
performing slightly better than during Cycle 7. The diffractive rejection is essentially
unchanged (to first order) from Cycle 7 except there is a shift in the mean position of the
cold mask which gives better second-order rejection on the downsloping diffraction spikes
and slightly worse on the upsloping diffraction spikes. A target can be positioned within
~0.08 pixel (~5.8 mas) of the coronagraphic hole low-scatter position, with a repeatability
of ~0.04 pixel (~2.9 mas) for two visits executed within the same orbit, with a roll between
visits. The coronagraphic focus was checked and no adjustment was needed. The Cycle 7
coronagraphic focus position is still the best focus. A slight adjustment was made to the
PAMC tilt to remove some coma that was not present during Cycle 7. The "hole 32x32
pixel subarray" field-of-regard (FOR) was adjusted by a few pixels in each direction due
to displacement of the hole image on the detector caused by the warm up at the end of
Cycle 7 and subsequent cool down following SM3B. A new ACQ FOR "gain" table (flat
field) was installed to handle hot and cold pixels, allowing Mode-2 acquisitions for targets
from H=4 to 17. The coronagraphic hole low scatter point, the "sweet spot," was checked
and a slight adjustment was required to achieve light suppression about the coronagraphic
hole comparable to or slightly better than that achieved during Cycle 7.
A. Schultz
30 Jan 2004
2003
NICMOS ISR 2003-011: NICMOS Cycle 12 Calibration Plan
This document summarizes the NICMOS Calibration Plan for Cycle 12. (CPC12). The
plan complements the SMOV3b, the Cycle 10 (interim), and the Cycle 11 calibration programs.
These previous programs have shown that the instrument is very stable, which has
motivated a reduction in the frequency of the monitoring programs for CPC12. Because
this stable behavior, systematic errors in the calibration become more important. For this
reason CPC12 includes two programs aimed at reducing such errors: the photometric
and spectroscopic recalibrations. The CPC12 also includes an outsourced calibration to
enable coronagraphic + polarimetric observations.
S. Arribas
11 Nov 2003
NICMOS ISR 2003-010: Removal of Cosmic Ray persistence From Science Data using the Post-SAA Darks
Latent or persisten images of cosmic ray hits following HST transits of the South Atlantic
Anomaly (SAA) can signicantly increase the noise in subsequent NICMOS science images. By
taking a pair of DARK exposures immediately following the exit of the SAA, a map of the persistent
signal can be made and then used to subtract this signal from the impacted images in that
orbit, thereby recovering much of the original S/N. We here describe an algorithm to do this
E. Bergeron and M. Dickenson
07 Oct 2003
NICMOS ISR 2003-009: NICMOS IntraPixel Sensitivity
A study of the NICMOS (Camera 3) intrapixel sensitivity is carried out after installation of
cryo-cooler in Cycle 11. The consistency of the procedure adopted here is tested by applying
it to the data in Cycle 7, as analyzed by Storrs et al (1999), and reproducing their
results. The intrapixel sensitivity in Cycle 11 is then measured and compared to that in
Cycle 7 (before the installation of the NICMOS cryo-cooler). We find 27% decrease in the
intrapixel sensitivity from Cycle 7 to Cycle 11 for both F110W (J-band) and F160W (Hband)
filters. The possibility of this effect being due to an increase in the stellar PSF over
this period is considered and discarded, as we only find 5% change in the PSF between the
two cycles.
.
C. Xu and B. Mobasher
23 Sep 2003
NICMOS ISR 2003-008: NICMOS Temperature Table
Nine NICMOS Cooling System (NCS) mnemonics and five temperature sensors are
extracted from the engineering telemetry and bundled together into an STSDAS FITS
table, the NICMOS Temperature Table. The FITS binary table has the same ipppssoot as
the corresponding science observation with a file name extension of "epc". The table is
created by the Engineering Data Processing System (EDPS) and can be retrieved with the
science data from the HST Archive for which OTFR has been requested. The table is provided
as an aid for use in calibration, temperature monitoring, and as a convenience to
science data users.The table will be available following installation OPUS 14.4.
A.B. Schultz
02 Sep 2003
NICMOS ISR 2003-007:Analysis of the HST Thermal Background as Seen by NICMOS and NCS
This report describes the results from the SMOV3b and Cycle 11 thermal background
calibration programs for NICMOS. The HST aft shroud is warmer due to ongoing degradation
of the external MLI and increased power of the instruments installed during SM3B
(ACS and the Nicmos Cooling System (NCS)). This warms the NICMOS fore-optics,
affecting the thermal background in long wavelength camera 2 and camera 3 filters by
approximately 20% beyond the increase due to DQE alone. This should be taken into
account when planning observations with these cameras in filters longward of 1.9
microns, or in especially broad filters such as F175W in camera 3. Since camera 1 has no
filters with a central wavelength longward of 1.9 microns, thermal emission effects in this
camera are not an issue, and have not been studied.
M. Sosey
14 May 2003
NICMOS ISR 2003-006: A Test of non-Standard Gain Settings for the NICMOS Detectors
We report on the results of a test program to explore the potential scientific benefit of using
non-standard gain settings in NICMOS observations. While this capability had originally
been included in the NICMOS design, it has never been used on orbit. We present our
analysis of the test data, discuss the potential scientific benefits, and outline the necessary
modifications to planning, implementation, and pipeline calibration of NICMOS data
taken with non-standard gain settings.
C. Xu & T. Boeker
13 May 2003
NICMOS ISR 2003-005: NICMOS Focus Monitoring in the Year Following SMOV 3b
Monthly monitoring of the NICMOS focus since SMOV 3b, following the installation of the NICMOS Cooling System (NCS) has revealed stable and consistent focus measurements in all three cameras. The focus values for each camera, which were measured and
uplinked to the Telescope during SMOV 3b are accurate and have not required any revision.
E. Roye
23 Apr 2003
NICMOS ISR 2003-004: Measuring the Cold Mask Offset
An unexpected increase in measured thermal background during the Cycle 11 early calibration
program caused speculation that the cold mask position could have shifted since
Cycle 7. To address this concern, a single orbit NICMOS program was executed (Program
ID: 9704) to obtain deep PSF images of the star LHS1846 in all three cameras.
Analysis of this data using the Phase Retrieval software package revealed a minimal
amount of cold mask shift since Cycle 7 and provided new, more accurate cold mask values
for the Tiny Tim PSF modeling software. It was concluded that the cold mask position
was not the cause of increased thermal background observed during the Cycle 11 early
calibration program. Increased thermal background has since been determined to be the
result of increased thermal load on the HST aft shroud due to the addition of ACS and
NCS during SM3b.
E. Roye
23 Apr 2003
NICMOS ISR 2003-003: NICMOS Monitoring Stability
A review of the NICMOS monthly flat field monitoring data (program IDs: 9326, 9640)
indicates that the NICMOS cameras are functioning as expected due in large part to the
stable temperature provided by the NICMOS Cooling System (NCS). The flat field data
(lamp-on) filter count rates 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. Note
that there was an increase in the number of grot affected pixels following Cycle 7 & 7N
with the addition of a large chunk in the lower right quadrant of NIC1. Dithering to
remove the affects of grot is recommended. A check of the NIC2 coronagraphic hole image
location shows hole motion similar to what was observed during Cycle 7 & 7N. Coronagraphic
observers should taylor their observations to minimize the effects of hole motion
on their data. Incremental monthly and super flat field reference files have been created
and delivered to the HST Archive for user support.
A.B. Schultz
02 Apr 2003
NICMOS ISR 2003-002: NICMOS Memory/Hardware Anamolies
NICMOS has experienced Error Detection and Correction (EDAC) single-bit EDAC
errors, TPG resets, and Intel Exception problems. Except for the last error, the EDAC
errors have been specific to the same memory address location. They are handled by software.
A Timing Pattern Generator (TPG) reset occurs when a spurious signal is generated
caused by a high energy particle event. The NICMOS flight software (FSW) was modified
to handle TPG resets. An Intel Exception will suspend the instrument. There is all likelihood
that additional similar EDAC errors, TPG resets, and suspends due to an Intel
Exception problem will occur during the on-orbit life time of NICMOS. This ISR is
intended to document the hardware errors and to be a resource when additional errors
occur.
A.B. Schultz
03 Feb 2003
NICMOS ISR 2003-001: High Signal-to-Noise, Differential NICMOS Spectrophotometry
We report analysis for NICMOS CAL/9642, High S/N Capability Characterization.The
purpose of this three orbit test was to establish NICMOS time domain stability in a
domain not previously tested for NICMOS. Observations of the bright (H = 6.13) G0 V
star HD 209458 were obtained using 1.8 second MULTIACCUMs with G141 on NIC3.
Exposure-to-exposure stability summed over the full spectrum provides S/N of 2000, i.e.
we demonstrated 0.5 mmag photometric precision treating the observations simply as
broad-band, time-series photometry. 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. A much better
result was obtained with application of such corrections, but the result cannot be considered
secure with comparison of only two orbits data. There is an excellent chance that in
applications with sufficient flux to generate the required Poisson limit, that well planned
NICMOS observations can provide differential spectrophotometric stability better than 1
part in 10,000 if not even significantly better.
R.L. Gilliland and S. Arribas
08 Jan 2003
2002
NICMOS ISR 2002-005: Implementation of the Temperature-Dependent Dark Correction in CalnicA
The pipeline implementation of the temperature-dependent dark correction, previously
only available to users as a WWW tool, is described. The algorithm used to generate the
darks is described, along with a description of how the IDL code and data that are used in
the WWW tool were incorporated into the usual HST pipeline model of code+reference
files. This implementation necessitated the creation of a new reference file type: the Temperature-
Dependent Dark (TDD) file. The design of this file type allowed many of the
hard constants to be removed from the code and put into the reference files, allowing more
convenient and flexible updating of the calibration parameters, if necessary.
R. Jedrzejewski
15 Jun 2009
NICMOS ISR 2002-004: SM3b Science Flats
This report describes the results from the NICMOS pointed flat-field calibration program
for SM3B. During programs 8998, 9557, and 9327, multiple sky background and lamp-on
exposures were obtained for all filters with all cameras. Analysis of the DQE reveals that
the relative countrates are at expected levels with respect to the operating temperature of
77K and are all within 8% of the ratio of modeled QE at 77K-to-62K performed during the
1997/1998 warm-up program. The resulting lamp-on minus background images were normalized
to create the final calibration reference files.
L. Mazzuca
17 Oct 2002
NICMOS ISR 2002-003: NICMOS Cycle 11 Calibration Plan
This document describes the NICMOS calibration activities for Cycle 11. It complements
the SMOV3b and the NICMOS Cycle 10 interim calibration programs. These activities
cover a period of 13 months and pursue the following major objectives: i) to monitor
the main instrument properties, ii) to test the model for generating darks, iii) to analyze in
detail the intra-pixel sensitivity effects for cameras 2 and 3, iv) to calibrate the polarimetry
mode, and v) to establish NICMOS stability when tracking differential (spectrophotometric)
changes over time. In addition, a contingency program (‘Pupil Transfer Function’)
will be activated if differential photometry over the chips obtained from SMOV data does
not reach the required levels of accuracy.
S. Arribas
16 Jul 2002
NICMOS ISR 2002-002b: SM3B NICMOS Focus Check
We report determinations of the NICMOS foci following cool down of the NICMOS detectors
after installation and activation of the NICMOS Cooling System (NCS). A focus
sweep in all three cameras executed on May 3, 2002 (program ID: 8977). Visual inspection
of the data indicated that a small amount of coma had been introduced since January
1999. Phase retrieval (STScI) and encircled energy (University of Arizona) measurements
were used to determine the best focus positions. The results of the two methods compared
quite favorably with each other. Adjustments to the current Pupil Alignment Mechanism
(PAM) positions were implemented on May 9, 2002 for Camera 1 & 2 (PAM1 & PAM2).
No focus adjustments were implemented for Camera 3 (PAM3) or for the Camera 2 coronagraphic
focus (PAMC). Adjustment of the intermediate focus position between Camera 1
& 2 (PAMI) will be managed starting during week 2002.133 by SMS.
A. B. Schultz
12 Jun 2002
NICMOS ISR 2002-002: NICMOS Cycle 10 Interim Calibration Plan
This document describes the NICMOS calibration activities for cycle 10 which will execute
after the completion of the SMOV3b program and before the start of the routine Cycle
11 calibration program. These activities cover a period of approximately 5 months and
pursue the following objectives: i) enable calibration of the imaging mode for the three
cameras and all the spectral elements, ii) complete the calibrations of the spectroscopic
mode, iii) monitor during this period key aspects of the instrument (optics stability, detectors
properties, scientific capability), and iv) to perform special calibrations (i.e. ‘gain
test’; accum-darks to support post-SAA observations) which were not implemented in the
SMOV3b program .
S. Arribas
14 Mar 2002
NICMOS ISR 2002-001: Bad Pixel Masks
A study of the frequency and location of the NICMOS bad pixels in each of the three cameras
had not been undertaken since the instrument was commissioned on-board HST in
1997. The original MASKFILEs located in the calibration database (CDBS) were compiled
with data taken during Systems Level Thermal Vacuum (SLTV) ground testing in
August 1996. This analysis examined dark frames taken during the initial lifetime of NICMOS,
March 1997 - January 1999, and details the creation of new bad pixel masks for
each camera. Updated flat field reference files were also created as a result of this analysis.
M. Sosey
14 Feb 2002
2001
NICMOS ISR-026: Characteristics of NICMOS Detector Dark Observations
This ISR describes the characteristics of the dark current for the NICMOS detectors. We then describe a recipe for generating `synthetic' dark current calibration reference files, which could be used to generate darks for any arbitrary sequence of MULTIACCUM reads, and present results of a comparison of such a synthetic dark with observed data.
NICMOS Group
09 Apr 2012
NICMOS ISR-1997-026: Characteristics of NICMOS Detector Dark Observations
This ISR describes the characteristics of the dark current for the NICMOS detectors. We then describe a recipe for generating `synthetic' dark current calibration reference files, which could be used to generate darks for any arbitrary sequence of MULTIACCUM reads, and present results of a comparison of such a synthetic dark with observed data.
NICMOS Group
09 Apr 2012
NICMOS ISR 2001-002: NICMOS OTFR: A Feasibility Study for Improved Scientific Return
We examine the feasibility and utility of performing bias drift corrections to NICMOS data
in a pipeline environment, with a specific eye towards the use of these routines in an “On
The Fly Reprocessing” (OTFR) system. We have investigated the feasibility of the required
calibration software implementation, as well as the scientific quality of the data that
would be produced by such a system. Our results indicate that the implementation would
be quite straight-forward, and that the calibrated data products would offer a vast
improvement over the currently-available products and would be immediately usable for
scientific analysis with little or no further post-pipeline processing.
H. Bushouse
14 Nov 2001
NICMOS ISR 2001-001: Performance of the NICMOS ETC Against Archived Data
A robust test of the newest version of the NICMOS Exposure Time Calculator (ETC) was
conducted in order to assess its performance against actual NICMOS datasets in predicting
an accurate Signal - to - Noise ratio for observation planning. All available signal
regimes were explored and the results show good agreement with the ETC for all cases.
M. Sosey
14 Nov 2001
2000
NICMOS ISR 2000-006: Results From the NCC/NICMOS Spare Detector June 2000 EMI Test
Analysis of power spectra and images obtained with a NIC3 flight spare detector, operate in conjunction with the NICMOS Cryo-Cooler (NCC) and mated with flight-like ground connections, indicate the total absence of any NCC indcued electromagnetic interference.
Glenn Schneider
20 Feb 2002
NICMOS ISR 2000-005: The new NICMOS Exposure Time Calculator: Software and Installation
This report describes the latest version of the NICMOS Imaging Exposure Time Calculator
(ETC) from a software developer and instrument support point of view. This ETC uses
STScI Calibration Data Base tables for instrument and telescope data, and STSDAS.SYNPHOT
for its throughput engine. It uses a self-contained library to calculate thermal background
due to telescope and instrument optics. We describe technical details of the
software in case observers wish to extend the capabilities of the ETC.
A. Sivaramakrishnan
14 Nov 2001
NICMOS ISR-2000-003 Results of the June 2000 NICMOS-NCS EMI Test
We summarize the findings of the NICMOS+NCS EMI Tests conducted at Goddard Space
Flight Center in June 2000. No NCS-induced noise was detected over a wide range of
read-out sequences and compressor speeds. The sensitivity of the test data was close to
on-orbit performance, thus the improved NCS design appears well suited for restoring
NICMOS capabilities without degrading its sensitivity.
S. Holfeltz
14 Nov 2001
NICMOS ISR-2000-004 NICMOS Warm Darks
NICMOS was commanded to Observe on June 19, 2000 and on June 30, 2000. A series of
MULTIACCUM and ACCUM darks were executed as part of the flight software (FSW
4.0C) installation. As expected, the darks were saturated at the current temperature of
~230o K. Real-time monitoring of the instrument during the dark observations indicates
that NICMOS is healthy and functioning as expected.
A. Schultz
14 Nov 2001
NICMOS ISR-00-001: The NICMOS Exposure Time Calculator: Algorithms and User Interface
This report describes the latest version of the NICMOS Exposure Time Calculator (ETC)
developed to support NCS-era HST NICMOS planning. We added a thermal optics library
to the ETC, and model various detector behaviors seen during the NICMOS end-of-life
period. There are no ad-hoc parameter values in the thermal optics library describing the
telescope and the NICMOS camera. This ETC supports imaging through all filters except
the grisms.
A. Sivaramakrishnan
14 Nov 2001
NICMOS ISR 00-002: NICMOS Dark Current Anomaly: Test Results
We report on the results of a laboratory test program to investigate the nature of the NICMOS
dark current anomaly. The test was designed to investigate one proposed mechanism
of signal electrons - excited into the conduction band by infrared photons - being stored at
low temperatures in charge traps throughout the detector material and released during
warmup. The test did not reproduce the bump, and the proposed scenario could not be
confirmed. The nature of the anomaly thus remains unexplained. We discuss this result
with regard to possible alternative explanations and options for testing them.
Boker, T.
25 Sep 2007
1999
NICMOS ISR-99-011: Long-Term Trends in the NICMOS Camera 2 Obscuration Pattern and Aberrations
Phase retrieval measurements of well-exposed NICMOS Camera 2 star images show that long-term changes occurred in coma and the cold mask position over the 1997-1998 lifespan of the instrument. The derived trends have been implemented in Version 5 of Tiny Tim.
J. Krist
14 Nov 2001
NICMOS ISR-99-010: NICMOS Temperature-Specific Darks
The various components of NICMOS dark images have been modeled and combined to make synthetic dark calibration files which are intended for use with observations in a temperature range from 61 to ~75 K.
B. Monroe
14 Nov 2001
NICMOS ISR-99-009: NICMOS Dark Current Anomaly: Models and Test Plans
The NICMOS dark current anomaly (the "bump") was a transient enhancement of the detector dark current observed during the on-orbit warmup of the instrument after its cryogen depletion in January 1999. We summarize our current understanding of the mechanism which causes the effect, and summarize plans to test the most likely scenario.
T. Boeker
14 Nov 2001
NICMOS ISR-99-008: GROT in NICMOS Cameras
Grot is exhibited as small areas of reduced sensitivity, most likely due to flecks of anti-reflective paint scraped off the optical baffles as they were forced against each other. This paper characterizes grot associated with all three cameras. The main products of this analysis are grot masks for each of the cameras.
M. Sosey
14 Nov 2001
NICMOS ISR-99-007: NIC 2 Growth Curves
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.
S. Holfeltz
14 Nov 2001
NICMOS ISR-99-006: NICMOS Coronagraphic Imaging Strategy
NICMOS Camera 2 reference images and observing strategies aimed at optimizing PSF subtraction are discussed.
A. Schultz
14 Nov 2001
NICMOS ISR-99-005: Camera 3 Intrapixel Sensitivity
Significant sensitivity variation across individual pixels, particularly at the pixel edges, is discussed and solutions are suggested to correct the photometry of point sources in images taken through the F110W and F160W filters.
A. Storrs
14 Nov 2001
NICMOS ISR-99-004: User's Guide to Polarimetric Imaging Tools
We present informal documentation for a group of IDL programs: POLARIZE.PRO, POLAR.PRO, and POLARPLOT.PRO This set of programs produce polarization coefficient images from observed data images taken with NIC1 or NIC2.
L. Mazzuca
14 Nov 2001
NICMOS ISR-99-003: NICMOS Optical Aberrations: Coma and Astigmatism
Trends in coma and astigmatism for each of the three NICMOS cameras have been derived using phase retrieval analysis of the data from the NICMOS focus monitoring program.
A. Suchkov
14 Nov 2001
NICMOS ISR-1999-012 NICMOS Calibration Lamp Stability
Characterizes the output, over its lifetime, of NICMOS internal calibration lamp number 1.
L. Bergeron
14 Nov 2001
NICMOS ISR-99-002: Color Dependence of NICMOS Flatfields
We report two methods for obtaining color dependent flat fields for NICMOS data. Programs to produce both types of flatfield are described, along with the reference data necessary.
A. Storrs
14 Nov 2001
NICMOS ISR-99-001: Analysis, Results and Assessment of the NICMOS Warm-up Monitoring Program
We summarize the results of the NICMOS warmup monitoring program. We estimate NICMOS performance during the NCS era, and briefly discuss possible implications for the cycle 9 calibration program.
T. Boker
14 Nov 2001
NICMOS ISR-99-001: Analysis, Results and Assessment of the NICMOS Warm-up Monitoring Program
We summarize the results of the NICMOS warmup monitoring program. We estimate NICMOS performance during the NCS era, and briefly discuss possible implications for future calibration programs.
T. Boker
14 Nov 2001
NICMOS ISR-98-019: NICMOS Mode-1 Coronagraphic Acquisition
This report describes the acquisition of bright targets for NICMOS coronagraphic observations.
A. Schultz
14 Nov 2001
1998
NICMOS ISR-98-017: Methodologies to Calibrating NICMOS Polarimetry Characteristics
Here we present the general linear theory of analysis for the case of three non-ideal polarizers.
L. Mazzuca
14 Nov 2001
We conduct TinyTim modeling of NICMOS camera 2 PSFs to assess limits to the accuracy of PSF subtraction imposed by color dependence, OTA focus breathing, and cold mask wiggling.
A. Suchkov
14 Nov 2001
NICMOS TIR 98-001: NICMOS/NCS EMI Test Data Results
Data from the NICMOS/Nicmos Cooling System Electromagnetic Interference test is summarized.
L. Bergeron
14 Nov 2001
NICMOS ISR-98-016: NICMOS Focus Data Reduction and Analysis Using Phase Retrieval
This ISR documents the process of measuring NICMOS focus and is written as a tutorial that can be used by anyone wishing to learn focus data reduction and analysis using the phase retrieval technique.
G. Galas
14 Nov 2001
NICMOS ISR-98-015: NICMOS Focus and HST Breathing
Biweekly NICMOS focus monitoring measurements are compared with the predictions of the three OTA focus breathing models.
A. Suchkov
14 Nov 2001
NICMOS ISR-98-014: Review of NICMOS Performance
We summarize the performance of the NICMOS instrument and compare the observed with the expected (pre-launch) capabilities.
D. Calzetti
14 Nov 2001
NICMOS ISR-98-011: NIC1 Narrow-band Earth Flats
We have created a set of 8 NIC1 narrow-band flats by combining images of streaked Earth flats. The processing of the flats, preliminary image analysis of the combined flats, and photometric analysis using a solar analog (P330E) and a white dwarf (G191) are discussed. We also discuss several new anomalies found in the data.
D. Gilmore
14 Nov 2001
NICMOS ISR-98-013: Second NIC3 Campaign Results
This report describes the point spread function (PSF) information for data taken in the second NICMOS camera 3 (NIC3) refocus campaign.
A. D. Storrs
14 Nov 2001
NICMOS ISR-98-012: NICMOS Camera 2 Coronagraphic ACQs
We have evaluated 38 Camera 2 on-board ACQs, and describe in this report the stability of coronagraphic target acquisitions.
A. Schultz
14 Nov 2001
NICMOS ISR-98-010: NICMOS Parallel Thermal Background: Results from SMOV and Cycle 7
This ISR presents the results of the analysis of NICMOS parallel thermal background data obtained as part of both SMOV and the cycle 7 calibration plan.
D. Daou
14 Nov 2001
NICMOS ISR-98-009: Focus Variation and the Orbital Phase of Observations
We report the effects of cyclic OTA 'breathing' on focus position for a variety of observational strategies with special attention given to NICMOS coronagraphic observations of bright targets.
A. Storrs
14 Nov 2001
NICMOS ISR-98-006: Observed Camera 3 Performance
This report describes the sensitivity of NICMOS camera 3 (NIC3) to point sources both during January 1998 'NIC3 Campaign', and outside the campaign.
A. Storrs
14 Nov 2001
NICMOS ISR-98-008: Statistics of Accumulating Signal
Here, formulae are presented for the variance of two estimators of the underlying Poissonian rate of accumulation of charge, with readout noise present. The formulae are tested using Monte-Carlo simulations and are applied to the standard NICMOS MULTI-ACCUM sequences using the known NICMOS dark properties.
W. Sparks
14 Nov 2001
NICMOS ISR-98-007: Possible Evidence for NICMOS Focus 'Precessional Breathing'
Combining the results of measurements of NICMOS focus and temperature (outside NICMOS dewar), we have found a correlation between detrended NICMOS focus and detrended temperature. The correlation suggests that there is a thermally induced (quasi)periodic component in NICMOS focus variation which has a time scale resembling the HST precessional period.
A. Suchkov
14 Nov 2001
OSG-CAL-98-01: NICMOS History Database and Web Tools
The history of NICMOS platescale, focus, and coronographic hole data has been stored in a database which is accessible via tools on the World Wide Web. The history tool which allows queries on the data, is available to the public.
C. Tullos
14 Nov 2001
NICMOS ISR-98-005: NICMOS Focus Field Variations (FFV) and Focus Centering
We present empirical results of a study of time dependence as well as PAM setting dependence of the variation of focus across the detectors' field of view for the NICMOS cameras.
A. Suchkov
14 Nov 2001
NICMOS ISR-98-004: NICMOS Focus Monitoring
We describe techniques to measure NICMOS foci and present the results of the NICMOS focus monitoring program as of February 1998. Procedures to correct for various affects which impact focus measurements are discussed.
A.Suchkov
14 Nov 2001
NICMOS ISR-98-003: NICMOS Camera 3 Pointed Flats
This report describes the NICMOS Camera 3 pointed flat fields program.
A. Schultz
14 Nov 2001
NICMOS ISR-98-002: First NICMOS On-Orbit Flat-Fields: Results from SMOV Data
This ISR presents the first set of on-orbit flat-field images obtained for NICMOS.
D. Calzetti
14 Nov 2001
REVISED Cycle 7 Calibration Plan
Update to Cycle 7 Calibration Plan
L. Colina
14 Nov 2001
NICMOS ISR-98-001: Cosmic Ray Persistence in NICMOS Data
In this report, we discuss the implications of cosmic ray persistence for the overall quality of NICMOS data, quantify the tradeoff between data quality and timing of observations relative to SAA passages, and discuss possible strategies to minimize the problem.
J. Najita
14 Nov 2001
NICMOS ISR-031: NICMOS Camera 2 Coronagraphic Acquisition
This report describes the NICMOS Camera 2 coronagraphic acquisition mode procedures for point sources, onboard software for faint targets and 'Reuse-Offset' for bright sources.
A. Schultz
14 Nov 2001
1997
NICMOS ISR-032: NICMOS SAA Contour Test: Results from SMOV data
This Instrument Science Report presents the results of the analysis of the South Atlantic Anomaly (SAA) contour test executed in June 1997.
D. Daou
14 Nov 2001
OSG-CAL-97-007: NICMOS Distortion Correction
The NICMOS distortion was measured by a series of images of the star cluster NGC1850. The degree of distortion was very small, amounting to about a one pixel shift at the corners. The pixel axes depart measurably from orthogonality being at most 0.2 degrees acute on camera 1.
C. Cox
14 Nov 2001
NICMOS ISR-030: Analysis Tools for the New Instruments: NICMOS and STIS images. I
This ISR presents the first set of software tools developed in IRAF/STSDAS and designed to handle the data format and organization of NICMOS and STIS image files. Whenever applicable, the tools propagate the error and data quality information of the input files to the output files.
D. Calzetti
14 Nov 2001
REVISED Cycle 7 Calibration Plan
Update to Cycle 7 Calibration Plan
L. Colina
14 Nov 2001
NICMOS ISR-029: The STScI NICMOS Pipeline: CALNICB, Reduction of Image Associations
This ISR defines CALNICB, the second and final stage of the STScI NICMOS calibration pipeline. CALNICB contains the elements of the pipeline which operate on the members of an association of NICMOS exposures.
J. MacKenty
14 Nov 2001
NICMOS ISR-028: The STScI NICMOS Pipeline: CALNICA, Single Image Reduction (Rev. A)
This ISR describes CALNICA, the single-image reduction portion of CALNIC, which produces individual calibrated images. We include a brief reminder of the NICMOS operational modes and data formats, then a description of the algorithmic steps in CALNICA, and then the reference files used by CALNICA.
H. Bushouse
14 Nov 2001
NICMOS ISR -1997-025: NICMOS Pointed Thermal Background: Results from On-Orbit data
This ISR presents the results of the analysis of NICMOS pointed thermal background data taken as part of the Servicing Mission Orbital Verification (SMOV).
D. Daou
14 Nov 2001
NICMOS ISR-1997-027: Camera 3 Performance
We present information on the curent optical performance of NICMOS camera 3 (NIC3) at J, H, and K, obtained without moving the HST secondary mirror, i.e. the performance obtainable today, outside a NIC3 'campaign'. We also assess the performance that can be expected if the HST secondary is refocused to bring NIC3 into focus.
A. Storrs
14 Nov 2001
NICMOS ISR-024: Persistence in NICMOS: Results from On-Orbit data
This ISR presents the results of the analysis of NICMOS persistence data taken as part of the Servicing Mission Orbital Verification (SMOV).
D. Daou
14 Nov 2001
OSG-CAL-97-04: NICMOS SM-2 SMOV Alignment Results
This technical memo documents the alignment calibration, spreadsheet model modifactions and the update of aperture tables using results from in-flight NICMOS alignment tests performed during the Second Servicing Mission Orbital Verification Phase.
O. Lupie
14 Nov 2001
NICMOS ISR-023: Persistence in NICMOS: Results from Thermal Vacuum Data
This ISR presents an analysis of the System Level Thermal Vacuum (SLTV) persistence tests performed with NICMOS.
D. Daou
14 Nov 2001
NICMOS ISR-022: Cosmic Rays on NICMOS: Results from On-Orbit Data
NICMOS dark frames obtained during SMOV are used to derive the sensitivity of the detectors to cosmic ray hits.
D. Calzetti
14 Nov 2001
NICMOS ISR-021: NICMOS Cycle 7 Calibration Plan
This report fully describes NICMOS calibration activities for cycle 7 as well as contingency calibration programs that will be executed only if the cameras show large physical displacements.
L. Colina
14 Nov 2001
NICMOS ISR-020: NICMOS Phase 2 Proposal Examples
This ISR describes the rationale for a series of Phase 2 examples of NICMOS observations. All the examples are built on the basis of our best understanding of the NICMOS performance before the completion of the Science Mission On-orbit Verification (SMOV).
D. Calzetti
14 Nov 2001
NICMOS ISR-018: NICMOS Paper Products: Build 1
This report details the features of the NICMOS paper products produced by the HST data pipeline. Here we provide detailed design of build 1, with a subsequent build 2 anticipated.
L. Colina
14 Nov 2001
1996
NICMOS ISR-016: The WWW NICMOS Exposure Time Calculator and Units Conversion Program
This ISR describes the World Wide Web implementation of the NICMOS Exposure Time Calculator and of the supporting software tool, the Units Conversion Program.
D. Calzetti
14 Nov 2001
NICMOS ISR 1996-019: Cosmic Rays on NICMOS: Results from Thermal Vacuum Data
The analysis of NICMOS data obtained during the System Level Thermal Vacuum Test in August 1996 has yielded some information on the sensitivity of the NICMOS detectors to cosmic ray hits.
D. Calzetti
14 Nov 2001
NICMOS ISR-017: Supported MULTIACCUM Sequences
In this ISR we define a specific set of MULTIACCUM mode exposure time sequences. We also define a modification to the RPS2 Proposal Editor (PED) which greatly simplifies the input of these MULTIACCUM exposure time sequences during Phase II proposal implementation.
J. MacKenty
14 Nov 2001
NICMOS ISR-009: The STScI NICMOS Pipeline: CALNICA, Single Image Reduction
This ISR describes CALNICA, the single-image reduction portion of CALNIC, which produces individual calibrated images. We include a brief reminder of the NICMOS operational modes and data formats, then a description of the algorithmic steps in CALNICA, and then the reference files used by CALNICA.
H. Bushouse
14 Nov 2001
NICMOS ISR-013: NICMOS Proposal Instructions 2: Patterns and Associations
In this ISR the optional parameters in the NICMOS Proposal Instructions which implement the automatic execution of patterns of observations are described.
J. MacKenty
14 Nov 2001
NICMOS ISR-012: NICMOS Proposal Instructions 1: General Instructions
In this ISR the Proposal Instructions for the NICMOS Science Instrument are described. This report discusses the possible SI configurations, modes, and most of the optional parameters.
J. MacKenty
14 Nov 2001
NICMOS ISR-015: Exposure Time & S/N Calculators for NICMOS
We describe a small suite of tools which have been developed to assist in the estimation of S/N ratios and exposure times for NICMOS observations for either point sources or extended sources. Finally, a similar set of tools is available for Multi-Object Spectroscopy using NICMOS's grisms.
C. Skinner
14 Nov 2001
NICMOS ISR-014: Flux Units and NICMOS
We propose to adopt the Jansky as the standard flux unit for NICMOS in our documentation and in observer-oriented software, and we provide here some simple formulae and tables to facilitate the conversion from other units into Jy.
C. Skinner
14 Nov 2001
We discuss the association of exposures. The association concept permits the use of multiple exposures in combination to produce data products. Examples include the identification and rejection of cosmic ray events and the measurement of the background for thermally limited NICMOS images.
J. MacKenty
14 Nov 2001
1995
NICMOS ISR-95-006: Effects of the NICMOS Array Flat-field Response on Observations.
In this report we use the results obtained from our detailed flat-field response tests to analyze numerically the likely effect of this behaviour on NICMOS photometry and imaging.
C. Skinner
14 Nov 2001
NICMOS ISR-95-004: NICMOS Design Reference Mission and Command Volume Estimate
We present an estimate of the uplink command volume associated with the NICMOS exposure commanding using the NICMOS Design Reference Mission developed by MacKenty and Kutina (ISR NICMOS-001).
W. Baggett
14 Nov 2001
NICMOS ISR-95-005: Characterisation of NICMOS Array Flat-field Response.
This ISR describes the likely flat-field performance of the NICMOS array detectors. A series of tests of one of the flight spare arrays are described, and then the results of these are presented, along with some initial analysis.
C. Skinner
14 Nov 2001
NICMOS ISR-002: NICMOS Data Formats in OPUS and STSDAS
In this ISR the contents and structure of the NICMOS science data files generated by the STScI ground system OPUS pipeline are described.
J. MacKenty
14 Nov 2001
NICMOS ISR-001: NICMOS Design Reference Mission and Ground System Volume Estimate
We construct an estimate of the distribution of NICMOS observing programs and their frequencies of occurrence in the post-SMOV era.
J. MacKenty
14 Nov 2001