KEYWORDS: Radio optics, Calibration, Heterodyning, Frequency combs, Laser radiometry, Radiometry, Near infrared, Optical calibration, Spectroscopy, Iron
Using laser heterodyne radiometry with a resolution of 100 MHz we have observed a selection of iron lines in the solar spectrum near 1565 nm with an approximate resolving power of 2,000,000 million. With a laser frequency comb as the wavelength calibration source we have achieved absolute frequency instability on measurements of single lines at better than 13 MHz in a 10 second averaging window, and SNR of over 5000 when averaging up to a 1 hour exposure. An amplitude servo on the laser power creates a stable, repeatable background level, allowing for simple extraction of the line depth.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.