The constant pursuit of challenging science cases in high-resolution spectrograph instruments on 10m-class telescopes has led to the development of the High-resolution Infrared SPectrograph for Exoplanet Characterization (HISPEC) Calibration Unit (CAL). This innovative unit is designed to enable groundbreaking scientific methodologies, including Doppler imaging of exoplanet atmospheres, precision radial velocity measurements, and high-contrast high-resolution spectroscopy of nearby exoplanets.
One of the key features of CAL is its ability to utilize four near-infrared (NIR) light sources encoded with wavelength information. These sources can be used synchronously during science observations or asynchronously during daytime calibrations. In addition, CAL incorporates a hollow cathode lamp (HCL) and a series of gas absorption cells that provide absolute calibration across a wide spectral range from 0.98 μm to 2.5 μm. To ensure stable and time-independent wavelength information during observation, CAL also incorporates a laser frequency comb (LFC). In the event of any LFC issues, a lower finesse astro-etalon serves as a reliable backup.
The design of CAL has drawn from the experience gained from the pathfinder instrument Keck Planet Imager and Characterizer (KPIC). Lessons learned from KPIC and other similar instruments will further inform the requirements for future instruments for Extremely Large Telescopes (ELTs).
With the introduction of the HISPEC Calibration Unit, astronomers and researchers will have access to even more precise calibration methods, empowering them to tackle increasingly complex scientific challenges. This advancement in calibration technology will undoubtedly contribute to further discoveries and advancements in the field of astrophysics.
FAQ
1. How does the HISPEC Calibration Unit facilitate precise calibration?
The HISPEC Calibration Unit incorporates various light sources, including near-infrared light sources and a hollow cathode lamp, to provide absolute calibration over a wide spectral range.
2. What scientific applications can benefit from the HISPEC Calibration Unit?
The HISPEC Calibration Unit enables Doppler imaging of exoplanet atmospheres, precision radial velocity measurements, and high-contrast high-resolution spectroscopy of nearby exoplanets.
3. What backup mechanism does the HISPEC Calibration Unit have for stable wavelength information?
In addition to the laser frequency comb, the HISPEC Calibration Unit utilizes a lower finesse astro-etalon as a backup for reliable wavelength information.
4. How does the design of CAL draw from previous instruments like KPIC?
The design of the HISPEC Calibration Unit incorporates lessons learned from the pathfinder instrument Keck Planet Imager and Characterizer (KPIC) to inform the requirements for future instruments for Extremely Large Telescopes (ELTs).