Description of the payload
Is a spectrometer with six tunable diode lasers dedicated to in situ measurements of trace compounds in the upper troposphere and the stratosphere up to 35 km altitude.
The 6 laser beams circulate in a multipass HERRIOTT cell located below the gondola. The lower mirror of the two-mirror cell is fixed at the top of a deployable mast. The distance between mirror is about 3.50 m. Given the curvature of the two identical mirrors, two stable optical configuration can be used : first 86 reflections and 300 m optical path, second 156 reflections and 554 m optical path, by moving the lower mirror 5 mm up.
The mast is deployed during the flight to have the first measurements at the tropopause. Around the instrument, a rigid metal frame encompasses it, in order to have a instrument-safe landing.
Inside the instrument, three liquid nitrogen cryostats, hold the six diode lasers and the 12 detectors.
Vertical profiles of concentrations of a great number of species like O3, CH4, CO, CO2, N2O, HNO3, NO2, NO, HCl, HOCl, H2O2, and COF2, are measured with a very high vertical resolution, a high sensitivity and a high precision.
Details of the balloon flight and scientific outcome
Launch site: Aérodrome de Gap-Tallard, Haute Alpes, France
Balloon launched by: Centre National d'Etudes Spatiales (CNES)
Balloon manufacturer/size/composition: Open balloon model 150z Zodiac - 150.000 m3
Balloon serial number: 150Z Nº 24
Payload weight: 791 kgs
Gondola weight: 465 kgs
The balloon was launched on June 29th, 1999 by dynamic method with the help of an auxiliary balloon.
The flight endured near 7 hours.
No additional data is available.
This was the first flight of the instrument.
External references and bibliographical sources