Photoacoustic sensor system and methodology for detecting target molecules

A photoacoustic sensor system for detecting target molecules in air samples or compressed air samples, comprising:

• a photoacoustic spectroscopy cell comprising:
• an acoustic resonator comprising an upper circular plate and a lower circular plate separated by a predetermined distance or height to form a cylindrical resonant cavity,
• an air or compressed air sampling system configured for directing a flow of air or compressed air through the cylindrical resonant cavity;
• and
• a first microphone arranged substantially at a center of one of the upper and lower circular plates for generating a first photoacoustic signal in response to absorption of modulated light within the cylindrical resonant cavity and a second microphone arranged at a circumferential edge of the one of the upper and lower circular plates for generating a second photoacoustic signal in response to the absorption of modulated light within the cylindrical resonant cavity;
• a light source configured to direct a modulated light beam through the cylindrical resonant cavity of the photoacoustic spectroscopy cell.