iSHELL: 1.1-5.3 micron high-resolution spectrograph and imager NASA InfraRed Telescope Facility(IRTF), Institute for Astronomy, University of Hawaii |
The iShell Observing Manual (27 August 2021). | |
Used to estimate the parallactic angle and differential atmospheric refraction for observations with SpeX. | |
iShell Log Template | |
iShell Guider Log Template | |
Used to locate A0V and/or G2V stars near a target object | |
iSHELL's exposure time calculator form L | |
Employs a set of ab-initio grating equations and simplified parameters that are accurate enough to describe the overall behavior of the cross-dispersors and the gratings |
Observers can compress data for transfer and uncompress on arrival by using the -C flag: 'sftp -C yourname@yourhost'. This should only be used for slow links since it requires extra CPU time.
If the observer prefers to download the raw (un-averaged) dark frames, this can be done using the above instructions, replacing the directory with /scrs1/cartman/2020A901/200205/ (for 5 Feb 2020 in the 2020A semester, in this example).
Spextool version v5. Spextool v5 reduces data obtained with iSHELL only, and is currently limited to reducing the discrete cross disperser settings. Future versions of SpeXtool will reduce both SpeX and iSHELL data. All users should read Sections 1 and 2 of the manual (found in Spextool/manuals/) before attempting to run the software, if only because some new IDL libraries are required. Raw K-band and L-band data can be downloaded to test drive the downloaded Spextool5 package. Comments, suggestions for improvements, and bug reports should be directed to Mike Cushing at michael.cushing@gmail.com.
iSHELL: a 1–5 micron R=80,000 Immersion Grating Spectrograph for the NASA Infrared Telescope Facility
John Rayner et al. 2022 Publications of the Astronomical Society of the Pacific, 134:015002 (26pp), 2022 January
Observers who use Spextool are also kindly asked to reference the following papers:
Spextool: A Spectral Extraction Package for SpeX, a 0.8-5.5 micron Cross-Dispersed Spectrograph
Michael C. Cushing, William D. Vacca and John T. Rayner
(2004, PASP 116, 362).
A Method of Correcting Near-Infrared Spectra for Telluric Absorption
William D. Vacca, Michael C. Cushing and John T. Rayner
(2003, PASP 115, 389).
Note: The general version of the telluric correction routines, xtellcor_general, previously available as a stand alone package, has now been incorporated into the Spextool package. Users must download the full Spextool package in order to use xtellcor_general.
Another paper may be of interest to iSHELL users:
iSHELL: construction, assembly, and testing
J. T. Rayner, A. Tokunaga, D. Jaffe, M. Bonnet, G. Ching, M. Connelley, D. Kokubun, C. Lockhart, E. Warmbier (2016, SPIE, 9908E, 84R)
Nonlinearity Corrections and Statistical Uncertainties Asociated with Near-Infrared Arrays
William D. Vacca, Michael C. Cushing and John T. Rayner
(2004, PASP 116, 352).
Contact John Rayner for further information or assistance |