VLT Instruments

  • FORS1 (FOcal Reducer and Spectrograph) and its twin, FORS2, are multi-mode instruments that can be used for imaging in the visible and for low-resolution spectroscopy.
  • ISAAC (Infrared Spectrometer And Array Camera) is a cryogenic infrared imager and spectrometer, observing in the 1 to 5 µm range.
  • UVES (Ultra-violet and Visible Echelle Spectrograph) is the high-dispersion spectrograph of the VLT, observing from 300 nm to 1100 nm, with a maximum spectral resolution of 110 000.
  • NACO is an Adaptive Optics facility producing images as sharp as if taken in space.
  • VIMOS (VIsible Multi-Object Spectrograph), a four-channel multiobject spectrograph and imager, allows obtaining low-resolution spectra of up to 1000 galaxies at a time.
  • FLAMES (Fibre Large Array Multi-Element Spectrograph) offers the unique capability to study simultaneously and at high spectral resolution hundreds of individual stars in nearby galaxies.
  • VISIR (VLT Imager and Spectrometer for the mid-InfraRed) provides diffraction-limited imaging at high sensitivity in the two mid infrared (MIR) atmospheric windows (8 to 13 µm and 16.5 to 24.5 µm).
  • SINFONI is a near-infrared (1 - 2.5 μm) integral field spectrograph fed by an adaptive optics module.
  • CRIRES (CRyogenic high-resolution InfraRed Echelle Spectrograph) provides a resolving power of up to 100 000 in the spectral range from 1 to 5 μm.
  • HAWK-I (High Acuity Wide field K-band Imager) is a near-infrared imager with a relatively large field of view.
  • X-shooter (a wide-band [UV to near infrared] spectrograph) is designed to explore the properties of rare, unusual or unidentified sources.

Current and planned telescopes and instruments on Paranal

 

VLTI Instruments

  • MIDI is a MID-infrared Interferometric instrument for photometry and spectroscopy
  • AMBER is a near infrared Astronomical Multi-Beam combineR — an instrument for
    photometric and spectroscopic studies, which combines the light of three telescopes.

Many of these instruments have been built, in collaboration with ESO, by consortia of European laboratories. Details of the Paranal Instruments can be obtained via the Science Portal pages of the Paranal Instrumentation.

Name: CRIRES FLAMES FORS1 FORS2 HAWK-I ISAAC
Description: Cryogenic high-resolution InfraRed Echelle Spectrograph [Mounted on UT1] Fibre Large Array Multi-Element Spectrograph, a multi-object, intermediate and high resolution spectrograph [Mounted on UT2] Visual and near-UV FOcal Reducer and low dispersion Spectrograph v.1 [Decommissioned, with some observing modes moved to FORS2] Visual and near-UV FOcal Reducer and low dispersion Spectrograph v.2 [Mounted on UT1] High Acuity Wide field K-band Imager [Mounted on UT4] Infrared Spectrometer And Array Camera [Mounted on UT3]
Slit Size: width 0.05–3.0 arcseconds; length 40 arcseconds N/A N/A N/A N/A N/A
Field of view: N/A 25 arcminute diameter 6.8 x 6.8 arcminutes (Standard Resolution collimator, SR) and 4.25 x 4.25 arcminutes (High Resolution collimator, HR) 6.8 x 6.8 arcminutes (Standard Resolution mode, SR) and 4.25 x 4.25 arcminutes (High Resolution mode, HR) 7.5 x 7.5 arcminutes (with a 15-arcsecond gap between the four arrays) 2.5 x 2.5 arcminutes (short wavelength, SW), 1.25 x 1.25 arcminutes (long wavelength, LW)
Spectral resolution: up to 100 000 5600–46 000 100 (SR)–400 (HR) 100 (SR)–400 (HR) N/A 200–11 500 (SW) and 180–10 000 (LW)
Wavelength range: 0.92–5.2 microns 370–950 nm 330–1100 nm (optimised for < 500 nm) 330–1100 nm (optimised for >650 nm) 0.85–2.5 microns 1–2.5 microns (SW) and 2.5–5 microns (LW)
Detectors: mosaic of 3 x Aladdin III InSb arrays. Each array has 1024 x 1024 pixels, of which 1024 x 512 pixels (two quadrants) are used. GIRAFFE, medium–high resolution spectrograph, equipped with a 2k x 4k pixel EEV CCD mosaic of 2 x 2k x 4k pixel E2V CCDs mosaic of 2 x 2k x 4k pixel MIT CCDs mosaic of 4 x 2048 x 2048 pixel HAWAII-2RG infrared array detectors one 1024 x 1024 pixel InSb-Aladdin array (LW) plus one 1024 x 1024 pixel Hawaii-Rockwell array (SW)
Pixel scale: 0.086 arcseconds/pixel 0.3–0.15 arcseconds/pixel 0.25 arcseconds/pixel (SR mode); 0.125 arcseconds/pixel (HR mode) 0.25 arcseconds/pixel (SR mode); 0.125 arcseconds/pixel (HR mode) 0.106 arcseconds/pixel 0.148 arcseconds/pixel (SW), 0.071 arcseconds/pixel (LW)
Note: N/A a link to another instrument, UVES, is available for three standard wavelengths (520 nm, 580 nm and 860 nm) and can reach up to spectral resolution of 47 000 N/A N/A N/A N/A
Start of operations: 2006 2003 1998 on UT1, moved to UT2 in 2004, now decommissioned with some observing modes moved to FORS2 1999 on UT2 — since 2004 on UT1 2007 1998 on UT1 — since 2009 on UT3
Science goals: search for exoplanets, Solar System objects, stellar evolution and abundances, star forming regions, active galactic nuclei stellar evolution, dwarf galaxies in the local group, high-redshift galaxies, Lyman-alpha emitting galaxies faint distant stars, planetary nebulae and Delta Cephei stars for distance determination, spectroscopy of field galaxies, galactic environment of quasars faint distant stars, planetary nebulae and Delta Cephei stars for distance determination, spectroscopy of field galaxies, galactic environment of quasars high-redshift galaxies and photometric redshift determination, star-forming regions faint outer Solar System bodies, brown dwarfs and low-mass stars, high-redshift galaxies
  NACO SINFONI UVES VIMOS VISIR X-shooter
Description:  Nasmyth Adaptive Optics System (NAOS) Near-Infrared Imager and Spectrograph (CONICA) [Mounted on UT4] Spectrograph for Integral Field Observations in the Near Infrared [Mounted on UT4] Ultraviolet and Visual Echelle Spectrograph [Mounted on UT2] VIsible MultiObject Spectrograph [Mounted on UT3] VLT Imager and Spectrometer for mid-Infrared [Mounted on UT3] Multi-wavelength medium resolution spectrograph [Mounted on UT2]
Slit Size: N/A N/A N/A N/A N/A N/A
Field of view: 56 x 56 arcseconds; 28 x 28 arcseconds; 14 x 14 arcseconds; 8 x 8 arcseconds (depending on the camera) 8 x 8 arcseconds, 3 x 3 arcseconds, or 0.8 x 0.8 arcseconds (depending on the width of the 32 slices the field of view is sliced into) N/A 4 quadrants, each with 7 x 8 arcminutes (separated by a 2-arcminute gap) 19.2 x 19.2 arcseconds (short wavelength, SW); 32.3 x 32.3 arcseconds ( long wavelength, LW) N/A
Spectral resolution: depends on the filter used: 400 in J, 500–1500 in H, 700–1400 in K, 700–1100 in L, 550 in SHK (1.3–2.6 microns) depends on the filter used: 2000, 3000, 4000 in J, H, K, respectively, and 1500 in H+K 40 000–with a narrow slit up to 80 000 (blue) and 110 000 (red) 180–2500 350–25 000 at 10 microns 4000–14 000
Wavelength range: 0.45–2.5 microns 1.1–2.45 microns 300–500 nm (blue); 420–1100 nm (red) 360–1000 nm 8–13 microns (SW); 16.5–24.5 microns (LW) 300–2500 nm (split in 3 arms)
Detectors: 1024 x 1024 pixel Aladdin-InSb infrared array detector 2k x 2k pixel Hawaii-2RG infrared array detector one blue CCD, 2k x 4k pixel thinned EEV CCD-44, plus a red CCD mosaic, made of an EEV chip of the same type (EEV CCD-44) and a MIT/LL CCID-20 chip one 2k x 4k pixel EEV CCD for each quadrant (full CCD used in spectroscopic modes, 2k x 2k in imaging modes) DRS (formerly Boeing) 256 x 256 BIB detectors 4k x 2k pixel E2V CCD (blue), 4k x 2k pixel MIT/LL CCD (red), 2k x 1k pixel Hawaii-2RG infrared array (NIR)
Pixel scale: 54; 27; 13; 17 milliarcseconds/pixel (depending on the camera) 0.25, 0.1 and 0.025 arcseconds/pixel (depending on the chosen field of view) 0.22 arcseconds/pixel (blue), 0.16 arcseconds/pixel (red) 0.205 arcseconds/pixel  0.075 or 0.127 arcseconds/pixel 0.16 (blue, red) and 0.21 (near-infrared) arcseconds/pixel
Start of operations: 2001 2004 1999 2002 2004 2008
Science goals: galactic: outflows and discs in young stellar objects, low-mass/substellar companions of nearby stars, T Tauri stars, red giants envelopes; extragalactic: quasars and host galaxies, obscured quasars, search for black holes in the centres of galaxies Galactic Centre, high-redshift galaxies, active galactic nuclei, starburst galaxies chemical abundances in galactic and extragalactic stars, interstellar clouds, quasar absorption lines deep spectroscopic survey of distant galaxies, galaxy evolution warm dust and gas; comets, circumstellar discs, star formation, quasars gamma-ray bursts, as well as spectra of low-metallicity stars, X-ray binaries, distant quasars and galaxies, nebulae 

VLTI instruments

Name: MIDI AMBER
Description: MID-infrared Interferometric instrument, combining two beams, either from the UTs or from the ATs. Near-infrared Astronomical Multi-Beam combineR, combining simultaneously up to three telescopes (all possible triplets of UTs are available, and a number of selected AT combinations)
Wavelength range: 8–13 microns 1.05–2.4 microns
Spectral resolution: 30–230 35; 1500; 12 000 (low, medium and high resolution, respectively)
Detector:  320 x 240 pixel Raytheon Si:As Impurity Band Conduction (IBC) array 512 x 512 pixel Hawaii infrared array detector (actual size is 1024 x 1024 pixel)
Start of operations: 2002 2004
Science goals: dust rings around black holes at the centres of quasars, circumstellar discs of forming stars, dust in the atmospheres of giant stars search for hot exoplanets, formation and evolution of stars, extragalactic sources