Lhires III Spectrograph

An instrument of reference

The Lhires III spectroscope is Shelyak Instruments’ “historic” instrument. Designed from the CNRS Astrophysics School in 2003 for the observation of Be stars, it has since found a wide range of applications.

Resolution & spectral range

With a resolving power of R=18,000, it provides access to Doppler velocity measurements, as well as incredible detail in the profile of a line.
The network module supplied as standard has 2400 lines/mm, giving full resolution. It can be replaced by an optional module, to access other resolutions – making the Lhires III a versatile instrument. You can adapt your resolution to your project. Weaker objects are then accessible: Novae, bright comets…

The spectral range covered is limited (of the order of ten nanometers, due to the need for high resolution), but you can select any wavelength in the visible range (400-750nm), thanks to a micrometer.

Numerous educational projects based on the Doppler effect are now possible, such as the rotation of Jupiter or Saturn.

Example of a spectrum of Jupiter,

showing the planet’s rotation

(inclination of the solar lines).

Aperture

The F/10 aperture makes it particularly well suited to Schmidt-Cassegrain telescopes. But it can also be mounted on other, more open instruments (by adding a Barlow lens).

Guiding system

Thanks to its mirror slit, the Lhires III enables the target star to be precisely positioned and held in the slit. A guiding camera (not supplied) enables the telescope’s movements to be controlled (autoguiding), ensuring optimum observation.

Interchangeable slit

The interchangeable slit supplied as standard (15-19-23-35µm) means that the instrument can be adapted to most observations, giving priority to resolution or brightness if required. Other slits are also available as options (wide slits, photometric slits), to further extend the possibilities.

Mechanical interfaces

The Lhires III is supplied with a standard interface for Schmidt-Cassegrain telescopes. If you wish to adapt it to a 2″ eyepiece holder, use the optional 2″ adapter.

The CCD adaptor supplied as standard is suitable for ATIK cameras. (13mm mechanical backfocus). We offer a wide choice of adapter rings in our accessories catalog.

The guiding camera is C-mount.

Going further with Lhires III

In addition to the astrophysical knowledge it can provide, the Lhires III is also a tool for collaboration between amateur and professional astronomers: studying Be-type stars, tracking variable stars, etc. Numerous scientific papers have been based on observations with a Lhires III.

The support of a large community

The Lhires III is widely used around the world, and you can find many examples of use and advice on the Spectro-L discussion list: https://groups.io/g/spectro-l or on the spectroscopy forum: ARAS.

Pricing subject to change based upon Euro to USD conversion at time of purchase