NICMOS Spectroscopy

NICMOS provides grism imaging spectroscopy in the spectral range between 0.8 and 2.5 microns. NICMOS is used in this mode of operation without any slit or aperture at the input focus, so all objects in the field of view are dispersed for true multi-object spectroscopy. The grisms reside in the NIC3 filter wheel which contains 3 grisms: G096, G141, and G206, which cover the entire NICMOS wavelength range with a spectral resolving power of ~200 per pixel. Important information regarding NICMOS spectroscopy can be found in Chapter 5 of the NICMOS Data Handbook, as well as on the Space Telescope European Coordinating Facility's NICMOS web page. If you want to calculate exposure times for Grism observations, do not use the local ETC, but instead refer to the Space Telescope European Coordinating Facility Grism ETC website. For more specific details about NICMOS spectroscopy, follow the links to the documents listed below.

NICMOS Spectroscopy Documentation

Advisories
Important updates, discoveries and developments that could potentially affect NICMOS observations, calibration, or data analysis.

FAQs
Frequently Asked Questions

Performance Summaries
Status reports reflecting the current understanding of instrument characteristics, performance and calibration

Handbooks
The NICMOS Instrument Handbook is the primary guide regarding the characteristics and use of the instrument. The HST Data Handbook is the primary guide for calibration, reduction and analysis of NICMOS data.

Instrument Science Reports
ISRs are technical reports written by members of the NICMOS Group about various aspects of the instrument and data. They usually contain in-depth information about specific topics.

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 07 Jan 2003 (pdf)

Papers and Proceedings
Selected NICMOS related published papers and workshop proceedings.

Domains of Observability in the Near-Infrared with HST/NICMOS and (Adaptive Optics Augmented) Large Ground-Based Telescopes
G. Schneider

Domains of Observability in the Near-Infrared with HST/NICMOS and (Adaptive Optics Augmented) Large Ground-Based Telescopes
G. Schneider

Presentation from 2002 SPIE Meeting: Post-NCS Performance of the HST NICMOS
A. B. Schultz

On-orbit Properties of the NICMOS Detectors on HST
L. Bergeron,A. Schultz,J. MacKenty,A. Storrs,W. Freudling,D. Axon,H. Bushouse,D. Calzetti,L. Colina,D. Daou,D. Gilmore,S. Holfeltz,J. Najita,K. Noll,C. Ritchie,W. Sparks,A. Suchkov

Tutorials
Cookbook style instructions, prescribed procedures, and helpful tips.

Examples:
Examples of how to use various NICMOS-related tools, calibration and analysis techniques.

Phase II Example: NICMOS Grisms using RPS2
Shows an example of how to complete a Phase II proposal using the NICMOS grisms.
NICMOS Group 05 Oct 2001 (html)

Phase II Example: NICMOS Grisms using APT
Shows an example of how to complete a Phase II proposal using the NICMOS grisms.
NICMOS Group 05 Oct 2001 (html)

Space Telescope Analysis Newsletters
STANs contain useful information regarding calibration and data reduction