This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
The Principal Investigator (PI)'s team will collaborate with personnel at the National Solar Observatory (NSO) and the University of Colorado to develop the Cryogenic InfraRed Spectrograph (CIRS) for Big Bear Solar Observatory's New Solar Telescope (NST), located on Big Bear Lake in the San Bernardino mountains of southern California. The CIRS system will be a substantial improvement over the two current solar infrared spectrographs in the US (on the NSO's McMath-Pierce telescope in Arizona and at University of Hawaii's Mees Solar Observatory on Maui). CIRS will permit high spatial resolution, high cadence observations of the Sun with high Zeeman sensitivity of solar magnetic fields. The PI will use CIRS to study the Sun's atmosphere from the photosphere through the chromosphere, as well as to make observations of dimmer and more difficult targets, such as sunspot umbrae and off-limb features.
Spectral observations of the Sun's photosphere and chromosphere utilizing the largely unexplored near-infrared (NIR) region of the spectrum will help solve many long-standing problems in solar astronomy, such as the disparity among magnetic field measurements in visible and infrared spectral regions and the origin of the solar chromosphere. The infrared spectrum beyond 1 mm is extremely useful for photospheric magnetic diagnostics, and also allows a unique window into the chromosphere lying atop the solar photosphere. Since high spatial resolution polarimetry at NIR wavelengths requires large aperture telescopes, this effort emphasizes the benefits of developing CIRS specifically for the 1.6 meter aperture NST at Big Bear.
Among its broader impacts, CIRS will be a significant test bed for more complicated IR spectrographs being planned for the Advanced Technology Solar Telescope (ATST), which is currently under development. Even after the ATST becomes operational, the NST will remain essential for community-directed campaign-style observations using CIRS. The development of the CIRS system will also allow the New Jersey Institute of Technology and Big Bear Solar Observatory to continue training the next generation of solar physicists and instrument builders. The data obtained by CIRS and the NST will certainly be used in many PhD theses, and will be openly accessible to the scientific community. A substantial portion of observing time on the NST will also be made available to the solar physics community.