NASA IRTF
Fall 2007 News

Last updated 06 September 2007

Proposal Deadline for February 1 - July 31, 2008
Spring 2008 semester observing proposals are due on Monday, October 1, 2007. See the information and application form here. (The current application form, revised August 2007, must be used. Available instruments include (1) SpeX, a 1-5 micron cross-dispersed medium-resolution spectrograph (up to R = 2,500); (2) CSHELL, a 1-5 micron high-resolution spectrograph (up to R = 30,000); (3) MIRSI, a 5-25 micron camera and low-resolution spectrometer (R = 100 to 200), (4) NSFCAM2, a 2048 ? 2048 pixel, 1-5 micron camera with a 0.04 arcsec/pixel scale and a complement of discrete filters, CVFs, and grisms; and (5) PI-instruments including a low-resolution 3-14 micron spectrograph and high-resolution spectrographs for 8-25 microns. Information on available instruments can be found at irtfweb.ifa.hawaii.edu/Facility/. Remote observing from any location will be supported.

Telescope Allocation Committee
The current TAC members are Yan Fernandez (U. Central Florida), Dave Glenar (Goddard), Joshua Emery (SETI), Dean Hines (Space Science Inst.), James Muzerolle (U. of Arizona), and Russel White (U. Alabama).

Spectral Library Available
The SpeX spectral library for FGKMLT stars is available here. The spectra are provided in FITS, text, PDF, and postscript formats. The papers by John Rayner, William Vacca, and Michael Cushing presented at this website should be referenced when this library is used.

NEO Spectral Survey
The MIT-IRTF Near-Earth Object spectral survey is underway, and many spectra are publicly available. See the side bar for more information or go to smass.mit.edu/minus.html.

Science Highlights and Publications
Our Science Highlights page is updated regularly as we receive the latest highlights from you. These highlights are sent to our funding agencies, NASA and NSF, to keep them abreast of the exciting and useful science obtained at the IRTF. Please keep submitting your recent publications using the form provided on our website, or send your reprints to Karan Hughes (hughes@ifa.hawaii.edu). Please acknowledge the IRTF in your publications following the information shown here and include in your papers the name of the instrument used, as this helps to insure future funding of IRTF instruments.

Instrumentation Update
NSFCAM2, with a 2048 x 2048 array, has been used on a conditional basis because of the high read noise, which decreases the sensitivity in the low-background filters (including J, H, and K). Several causes of the excess noise have been identified, and solutions are being implemented. Once all the solutions are applied, the read noise is expected to be about 18 to 20 e- rms. Some of the solutions require custom replacement components, which has resulted in delays. For the status of this instrument, contact Eric Tollestrup (tolles@ifa.hawaii.edu). NSFCAM2 is currently best suited for observations in the thermal infrared (3-5 microns) since it is background limited and the image quality is excellentexcellent.

The SpeX guider can be used for 1-5 µm imaging. Although it is not optimum given its engineering grade array (used for acquisition and guiding), it is still better than the current NSFCAM2 array at JHK. Observers who wish to use SpeX rather than NSFCAM2 for JHK imaging should consult with John Rayner.

MIRSI Upgrade
MIRSI is currently undergoing an upgrade, which should be completed around the end of 2007. The most obvious changes will be a new graphical user interface that will have the same look and feel as the facility instrument GUIs. In addition, various hardware, firmware, and software upgrades will make MIRSI more reliable and robust. Finally, new readout schemes will be implemented to improve the sensitivity, improve the fix pattern noise, and eliminated various readout artifacts. These upgrades are happening without taking MIRSI out of operation. When the new GUI is implemented, all MIRSI observers will need to get additional training on how to use MIRSI. Contact

CSHELL Upgrade
The user GUI for CSHELL is being improved so that it has a format similar to that of SpeX.

New Secondary Mirror
Eric Tollestrup has obtained an NSF grant to measure the spherical aberration of the primary mirror and to fabricate a new secondary mirror with a surface figure that removes the spherical aberration and other high-order aberrations. The first stage of this project (to fabricate a prime focus instrument package and measure the aberrations) has been completed this past spring. The data are being analyzed to derive specifications for the new secondary mirror, which should be installed on the IRTF during the 2008B semester. With the new secondary mirror, the majority of the static aberrations will be substantially corrected, if not eliminated, resulting in significantly better image quality. Upon completion, the IRTF image quality should be primarily limited by atmospheric seeing and mirror cell induced astigmatism.

Remote Observing
Interest in remote observing has continued to grow since it was first offered at the IRTF in August 2002. About 60% of the observing time is now being used remotely. We support remote observing from any location with broadband Internet access for any project that utilizes IRTF instruments. See here for more information.

New Cooperative Agreement
A Cooperative Agreement to fund IRTF operations for five years has been submitted to NASA. This new agreement will cover the period of February 2008 to January 2013. In addition to continuing operations, we plan to undertake work to improve the image quality of the telescope. Separate proposals will be submitted to the NSF to provide additional instrumentation, particularly to support NEO follow-up observations.