Photofragment chlorine atoms in the ²P_j states from Cl₂ at 266–500 nm are measured by a resonance‐enhanced multiphoton ionization technique. The measured branching ratio of [Cl*(²P_1/2)]/[Cl(²P_3/2)] increases monotonically with dissociation wavelengths from (9.5±1.8)×10⁻³ at 308 nm to (4.7±0.5)×10⁻¹ at 475 nm. At 375 nm≤λ≤475 nm, Doppler profiles of the chlorine atoms indicate adiabatic formation of two Cl(²P_3/2) from the ¹Π(1_u) state of Cl₂ and Cl(²P_3/2)+Cl*(²P_1/2) from the B ³Π(0⁺_u) state. On the other hand, at a shorter wavelength (308 nm), Cl*(²P_1/2) is generated from the ¹Π(1_u) state through nonadiabatic transitions during the dissociation. The relative contribution of the ¹Π(1_u)←X ¹Σ(0⁺_g) and B ³Π(0⁺_u)←X ¹Σ(0⁺_g) transitions in the photoabsorption is estimated from the obtained branching ratios at 375 nm≤λ≤475 nm.

The international journal of Aerosol and Air Quality Research (AAQR) covers all aspects of aerosol science and technology, atmospheric science and air quality related issues.

Air quality low-cost sensors (LCSs) are affordable and can be deployed in massive scale in order to enable high-resolution spatio-temporal air pollution information. However, they often suffer from sensing accuracy, in particular, when they are used for capturing extreme events. We propose an intelligent sensors calibration method that facilitates correcting LCSs measurements accurately and detecting the calibrators’ drift. The proposed calibration method uses Bayesian framework to establish white-box and black-box calibrators. We evaluate the method in a controlled experiment under different types of smoking events. The calibration results show that the method accurately estimates the aerosol mass concentration during the smoking events. We show that black-box calibrators are more accurate than white-box calibrators. However, black-box calibrators may drift easily when a new smoking event occurs, while white-box calibrators remain robust. Therefore, we implement both of the calibrators in parallel to extract both calibrators’ strengths and also enable drifting monitoring for calibration models. We also discuss that our method is implementable for other types of LCSs suffered from sensing accuracy.

The reactions O(¹D)+HCl→OH+Cl (1a) and OCl+H (1b), O(¹D)+DCl→OD+Cl (2a) and OCl+D (2b), and O(¹D)+Cl₂→OCl+Cl (3) are studied at an average collision energy of 7.6, 7.7, and 8.8 kcal/mol for (1), (2), and (3), respectively. H, D, and Cl atoms are detected by the resonance‐enhanced multiphoton ionization technique. The average kinetic energies released to the products are estimated from Doppler profile measurements of the product atoms. The relative yields [OCl+H]/[OH+Cl] and [OCl+D]/[OD+Cl] are directly measured, and a strong isotope effect (H/D) on the relative yields is found. The fine‐structure branding ratios [Cl(²P_1/2]/[Cl(²P_3/2)] of the reaction products are also measured. The results suggest that nonadiabatic couplings take place at the exit channels of the reactions (1a) and (2a), while the reaction (3) is totally adiabatic.