Outline • CARMENES instrument outline
Summary table • The most relevant engineering parameters of the instrument
Observing • Open-time proposals through CAHA or Opticon, observing manual, sensitivity...
Spectrographs • Comparable spectrographs in the visible and/or the near-infrared at 4 m-class telescopes or larger


CARMENES [kár-men-es] (Calar Alto high-Resolution search for M dwarfs with Exoearths with Near-infrared and optical Échelle Spectrographs) is a next-generation instrument built for the 3.5m telescope at the Calar Alto Observatory by a consortium of German and Spanish institutions. It consists of two separated spectrographs covering the wavelength ranges from 0.52 to 0.96 µm and from 0.96 to 1.71 µm with spectral resolutions R = 80,000-100,000, each of which performs high-accuracy radial-velocity measurements (∼1 m s-1) with long-term stability. The fundamental science objective of CARMENES is to carry out a survey of ∼300 late-type main-sequence stars with the goal of detecting low-mass planets in their habitable zones. We aim at being able to detect 2 MEarth planets in the habitable zone of M5V stars. The CARMENES first light with the two NIR and VIS channels working simultaneously occured in Nov 2015; the science survey of Guaranteed Time Observations started on 01 Jan 2016 and will last for at least five years

In the left menu you can get extra information on the Consortium (institutions, key names, sponsors, all consortium members and guests, industrial collaborators and manufacturers) and our Science (publications, PhD/MSc/BSc theses, conferences) There is another CARMENES website maintained by CAHA

Summary table

VIS channel NIR channel
Wavelength coverage, Δλ* 520-960 nm
960-1710 nm
Detector 1 x 4kx4k e2v CCD231-84 2 x 2kx2k Hawaii-2RG
(2.5 μm cutoff)
Wavelength calibration Th-Ne lamps & Fabry-Pérot etalon U-Ne lamps & Fabry-Pérot etalon
Working temperature, Twork 285.000 ± 0.005 K 140.000 ± 0.005 K
Spectral resolution, R 94,600 80,400
Mean sampling 2.8 pixels
Mean inter-fibre spacing 7.0 pixels
Cross disperser Grism, LF5 glass Grism, infrasil
Reflective optics coating Silver Gold
No. of orders 55 28
Échelle grating 2 x Richardson Gratings R4 (31.6 mm-1)
Target fibre field of view 1.5 arcsec
A&G system field of view 3 arcmin
A&G system band Approx. R

*: There is a dichroic at 960 nm that splits the light into two beams, one for each channel. The detectors are actually sensitive until 1050 nm (VIS) and from 900 nm (NIR). There are some gaps in the wavelength coverage wider than 10 nm redwards of 1550 nm. The strongest telluric absorption is at the JH boundary


How to get CARMENES observing time?

How to observe with CARMENES?


Comparable spectrographs in the visible and near infrared
Acronym Name Telescope Year
HIRES High Resolution Spectrograph for the E-ELT European-Extremely Large Telescope E-ELT 2025+
NIRPS + HARPS NIRPS + HARPS ESO 3.6 m La Silla 2020
GIARPS GIANO-B + HARPS-N Telescopio Nazionale Galileo 2017
Comparable spectrographs in the near infrared
Acronym Name Telescope Year
Veloce The Veloce spectrograph Anglo-Australian Telescope 2020+
CRIRES+ CRyogenic high-resolution InfraRed Échelle Spectrograph Upgrade Very Large Telescope UT1 2020
MAROON-X Magellan Advanced Radial velocity Observer Of Neighboring eXoplanets Gemini North 2020
NIRPS Near Infra Red Planet Searcher ESO 3.6 m La Silla 2020
SPIRou A nIR high-precison-RV échelle spectropolarimeter for CFHT Canada-France-Hawai'i Telescope 2018
HPF Habitable zone Planet Finder Hobby-Eberly Telescope 2017
IRD Infrared Doppler instrument Subaru 2017
GIANO-B Fibre-fed Near-Infrared High Resolution Spectrograph Telescopio Nazionale Galileo 2017
iSHELL Immersion Grating Echelle Spectrograph NASA IRTF 2016
GIANO Long-slit Near-Infrared High Resolution Spectrograph Telescopio Nazionale Galileo Decommissioned
NAHUAL Near-infrAred High-resolUtion spectrogrAph for pLanet hunting Gran Telescopio Canarias Cancelled
Comparable spectrographs in the visible
Acronym Name Telescope Year
ESPRESSO Échelle SPectrograph for Rocky Exoplanet- and Stable Spectroscopic Observations Very Large Telescope 2017
HORUS High Optical Resolution Ultra-Stable Spectrograph Gran Telescopio Canarias 2016
HARPS-N High Accuracy Radial velocity Planet Searcher-North Telescopio Nazionale Galileo 2012
PFS Planet Finder Spectrograph Magellan II Telescope 2010
HARPS High Accuracy Radial velocity Planet Searcher ESO 3.6m La Silla 2003
HRS High-Resolution Spectrograph Hobby-Eberly Telescope 2001
UVES Ultraviolet and Visual Échelle Spectrograph Very Large Telescope UT2 2000
HIRES HIgh REsolution Échelle Spectrograph Keck I Telescope 1996

By comparable we mean high-resolution spectrograph with wide, simultaneous, spectral coverage at 4 m-class telescopes or larger. See also other échelle spectrographs (links at the UCM) and the Caballero (2015) review at Pathways 2015