Poster Presentation Astronomical Society of Australia Annual Scientific Meeting including HWWS 2013

A stable wavelength comb for precise radial velocity measurements (#219)

Tobias Feger 1 , Joao Bento 1 , Mike Ireland 1
  1. Macquarie University, North Ryde, NSW, Australia

We present a novel, stable and inexpensive wavelength scale reference based on a photonic cavity with the potential of mass replication for current and future (arrays of) radial velocity spectrographs. The primary purpose of using a photonic cavity is to obtain a dense sinusoidal wavelength comb with spectral coverage between 450-650nm. Its basic setup is an unbalanced all-fibre white light Mach-Zehnder interferometer assembled out of two off-the-shelf available fibre couplers. To reach a good long-term stability the interferometer is actively locked by monitoring phase deviations of an extremely stable atomic line. The full system operates in closed loop, i.e. any phase shift measured by a photo receiver will be actively corrected using a phase feedback component (e.g. fibre heater). The setup, its characterization and results from long-term stability tests are being presented with this poster.