CRIRES+
CRIRES+ is the upgraded version of the CRIRES instrument, originally a high-resolution near-infrared spectrograph at the Very Large Telescope (VLT) in Chile, operated by the European Southern Observatory (ESO). In 2014, CRIRES was taken offline and sent to Germany for a major upgrade. This project, called CRIRES+, transformed the instrument into a cross-dispersed spectrograph, increasing the wavelength range it could cover simultaneously by a factor of ten. The upgrade also introduced a new spectropolarimetric unit, replaced detectors and optical components, enhanced the calibration system, and completely rewriting the data reduction system.
CRIRES cryostat in the main assembling hall of the ESO headquarters in Garching (Germany). Some of the instrument optics are still inside.
Uppsala University is part of the CRIRES+ consortium, together with the Thüringer Landessternwarte Tautenburg, the Institute for Astrophysics Göttingen, and the INAF Arcetri Astrophysical Observatory. We are responsible for the design and manufacturing of the polarimetric unit, and the design and implementation of the Data Reduction System. We also contribute to the development of new detectors, supported by a grant from the Knut and Alice Wallenberg Foundation.
Spectra of the star TW Hya taken with the original CRIRES and CRIRES. You can see that the wavelength range covered by CRIRES+ in one exposure is far greater.
The CRIRES+ instrument was installed at the VLT on Unit Telescope 3 at the beginning of 2020 and saw first light in February of that year. Despite the challenges posed by the COVID-19 pandemic, which required remote commissioning from Europe, the instrument was successfully commissioned and verified for scientific operations throughout 2021. It was then made available to the scientific community in October 2021.
CRIRES+ allows astronomers to significantly advance their understanding of stellar magnetic fields, detect planets in the habitable zones of low-mass stars, characterize exoplanet atmospheres, and much more. The new capabilities, supported by state-of-the-art data reduction software, enable the community to fully leverage the instrument's potential.
For more details about CRIRES+, visit the instrument page at ESO.
