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Bologna Submillimeter Spectrometer (BoSS)

Frequency range: 75 - 1600 GHz

The radiation sources are either several Gunn diodes (covering the 75-134 GHz range) or passive multipliers (x2, x3, x6, x9) in cascade driven by the Gunn diode oscillators themselves. The sources are phase-locked to the suitable harmonic of a frequency synthesizer referenced to an external rubidium frequency standard. The frequency modulation of the radiation is obtained by sine-wave modulating the reference signal of the wide-band Gunn synchronizer. The spectrometer is equipped with different absorption cells: one is equipped with two cylindrical hollow electrodes at both ends (DC discharge system) and is wounded with a plastic pipe for liquid nitrogen circulation; another cell is connected to a quartz reactor designed for Flash Vacuum Pyrolysis. A Schottky barrier detector (below 200 GHz), two Virgina Diodes detectors (~200-500 GHz), or liquid-helium-cooled InSb bolometer (up to 3 THz) are used for detection in the different frequency ranges. The radiation is phase-sensitively detected by a lock-in amplifier tuned at twice the modulation frequency, so that the second derivative of the spectrum profile is displayed.

Pulsed Jet - Fourier Transform MicroWave spectroscopy (PJ-FTMW)

Frequency range: 6 - 18 GHz

COBRA (Coaxially Oriented Beam-Resonator Arrangement)-type pulsed-jet Fourier-transform microwave spectrometer. Pulsed supersonic expansion of the sample in gas carrier trough a solenoil valve in a Fabry-Pérot-type cavity.