Laser frequency combs (LFCs) are well on their way to becoming the next-generation calibration sources for precision astronomical spectroscopy. This development is considered key in the hunt for low-mass rocky exoplanets around solar-type stars whose discovery with the radial-velocity method requires cm/s Doppler precision. In order to prove such precise calibration with an LFC, it must be compared to another calibrator of at least the same precision. Being the best available spectrograph calibrator, this means comparing it to a second - fully independent - LFC. Here, we report on a test in which two separate LFCs were used to simultaneously calibrate an astronomical spectrograph. Our installation of two LFCs at the ultra-stable two-channel spectrograph HARPS allowed characterization of their relative stability and consistency in calibration at the highest available level. Although the test was limited in time, the results confirm the 1 cm/s stability that has long been anticipated by the astronomical community.
It may interest you
An international team of scientists, with the participation of the Instituto de Astrofísica de Canarias (IAC), has discovered a planet of the size of Neptune orbiting in rather more than a week around AU Microscopii, a young star a little over of 30 light years away, and surrounded by a disc of debris left over from its formation. The data were obtained with NASA’s Transiting Exoplanet Survey Satellite (TESS) and the Spitzer Space Telescope (now retired from service). The Discovery is published today in Nature magazine. The finding in this system, abbreviated as AU Mic, will be a uniqueAdvertised on
A study led by researchers at the Instituto de Astrofísica de Canarias (IAC), making comparison between the discs of several pairs of spiral galaxies, active and non-active, concludes that in the discs of the former the rotational motion of the stars is of greater importance. This study, just accepted for publication in Astronomy & Astrophysics Letters, is the first evidence for large scale dynamical differences between active and non-active galaxies in the local universe. The astronomers participating are from the Instituto de Astrofísica de Canarias (IAC) and the University of La LagunaAdvertised on
A study, led by researchers at the Instituto de Astrofísica de Canarias (IAC) and carried out with OSIRIS, an instrument on the Gran Telescopio Canarias (GTC), has found the most densely populated galaxy cluster in formation in the primitive universe. The researchers predict that this structure, which is at a distance of 12.5 billion light years from us, will have evolved becoming a cluster similar to that of Virgo, a neighbour of the Local Group of galaxies to which the Milky Way belongs. The study is published in the specialized journal Monthly Notices of the Royal Astronomical SocietyAdvertised on