Spectroscopic-network-assisted precision spectroscopy

Szeminárium Spectroscopic-network-assisted precision spectroscopy
Előadó

Császár Attila

ELTE
Kapcsolattartó Dr. Sulik Béla
Időpont 2019-12-05 11:00
Helyszín Atomki, nagyelőadó (Debrecen, Bem tér 18/c, XII. épület 3. emelet)
Esemény leírása

Frequency-comb lasers and cavity-enhanced optical techniques have revolutionized molecular spectroscopy, their combination allows ultrahigh-precision measurements of saturated Doppler-free lines. As demonstrated here, such optical techniques can greatly improve the information content of line-by-line spectroscopic databases, utilized by a vast number of engineers and scientists, once the generalized Ritz principle, that is the concept of spectroscopic networks, is applied for the selection of the lines targeted for measurement. As a proof of concept, we measured a connected list of 150 carefully-selected near-infrared (7000-7350 cm-1) transitions for H2O-16 with 2-5 kHz accuracy. Augmented with 28 highly-accurate literature lines determined in the microwave region, these experiments allow the precise determination of the lowest ortho energy of  H2O-16, 23.79436122(25) cm-1, 145 energy levels on the ground vibrational state with an accuracy exceeding that of terahertz studies, and reference calibration wavenumbers for 1042 transitions in a wide wavenumber range (0-1000 and 6350-8000 cm-1).