Proceedings Article | 17 October 2007
KEYWORDS: Receivers, Heterodyning, Superconductors, Oscillators, Spectroscopy, Ozone, Cryogenics, Satellites, Terahertz radiation, Signal detection
TELIS (TErahertz and submm LImb Sounder) is a three-channel balloon-borne heterodyne spectrometer for
atmospheric research. The observational techniques of TELIS can be compared to the presently flying MLS instrument
on board NASA's EOS-Aura satellite, but TELIS is built with a new generation of cryogenic heterodyne detectors and
novel compact systems suitable for integration into the confined space of a balloon borne cryostat. TELIS will fly on the
MIPAS-B2 gondola. The two instruments together will yield the most complete set of stratospheric constituents,
measured so far. TELIS is a cooperation between the European institutes DLR (PI-institute), RAL and SRON. First
flight foreseen in the spring of 2008 from Teresina, Brasil.
The three TELIS receivers provide simultaneous vertical profile measurement of a range of molecules. The 500 GHz
channel is developed by RAL and will produce vertical profiles of BrO, ClO, O3 and N2O. The 1.8 THz channel is
developed by DLR and will mainly target the OH radical, and will also measure HO2, HCl, NO, NO2, O3, H2O, O2 and
HOCl. Finally the 480 - 650 GHz channel is developed by SRON and IREE and will measure profiles of ClO, BrO, O3,
HCl, HOCl, H2O and its 3 isotopomers, H2O2, NO, N2O, HNO3, CH3Cl and HCN.
In this paper, the science and technology of TELIS will be discussed with emphasis on the channel developed by
SRON. It contains a Superconducting Integrated Receiver (SIR), which combines on a 4x4 mm2 chip the low-noise SIS
mixer and its quasioptical antenna, a superconducting phase-locked Flux Flow Oscillator (FFO) acting as Local
Oscillator (LO) and a SIS harmonic mixer (HM) for FFO phase locking. The latest results from the pre-flight test and
integration campaigns will be presented.
