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Kalogerakis KS. A previously unrecognized source of the O 2 Atmospheric band emission in Earth's nightglow. SCIENCE ADVANCES 2019; 5:eaau9255. [PMID: 30906860 PMCID: PMC6426466 DOI: 10.1126/sciadv.aau9255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 01/31/2019] [Indexed: 06/09/2023]
Abstract
Earth's night sky continuously produces a faint chemiluminescence known as nightglow. Two prominent nighttime emissions around 90 km are the O2 Atmospheric and the OH Meinel band systems. Despite a plethora of studies since their identification seven decades ago, substantial gaps persist in our understanding of the mechanisms that control them. This report shows that oxygen atoms connect these two emissions: Fast, multiquantum, vibrational-to-electronic relaxation of OH(v) by O atoms activates a pathway that generates O2 Atmospheric band emission. This newly discovered source exhibits a strong altitude dependence and can contribute a majority of the observed O2 Atmospheric band emission when the peaks of the OH and O-atom layers overlap. The new findings call for a reinterpretation of Earth's nightglow emissions and a revision of relevant atmospheric models.
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Kalogerakis KS, Matsiev D, Cosby PC, Dodd JA, Falcinelli S, Hedin J, Kutepov AA, Noll S, Panka PA, Romanescu C, Thiebaud JE. New insights for mesospheric OH: multi-quantum vibrational relaxation as a driver for non-local thermodynamic equilibrium. ANNALES GEOPHYSICAE 2018; 36:13-24. [PMID: 29503514 PMCID: PMC5833932 DOI: 10.5194/angeo-36-13-2018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The question of whether mesospheric OH(υ) rotational population distributions are in equilibrium with the local kinetic temperature has been debated over several decades. Despite several indications for the existence of non-equilibrium effects, the general consensus has been that emissions originating from low rotational levels are thermalized. Sky spectra simultaneously observing several vibrational levels demonstrated reproducible trends in the extracted OH(υ) rotational temperatures as a function of vibrational excitation. Laboratory experiments provided information on rotational energy transfer and direct evidence for fast multi-quantum OH(high-υ) vibrational relaxation by O atoms. We examine the relationship of the new relaxation pathways with the behavior exhibited by OH(υ) rotational population distributions. Rapid OH(high-υ) + O multi-quantum vibrational relaxation connects high and low vibrational levels and enhances the hot tail of the OH(low-υ) rotational distributions. The effective rotational temperatures of mesospheric OH(υ) are found to deviate from local thermodynamic equilibrium for all observed vibrational levels.
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Affiliation(s)
| | - Daniel Matsiev
- Center for Geospace Studies, SRI International, Menlo Park, California, USA
| | - Philip C. Cosby
- formerly at: Molecular Physics Laboratory, SRI International, Menlo Park, California, USA
| | - James A. Dodd
- Air Force Research Laboratory (AFRL), Space Vehicles Directorate, Kirtland Air Force Base, New Mexico, USA
| | - Stefano Falcinelli
- Department of Civil and Environmental Engineering, University of Perugia, Perugia, Italy
| | - Jonas Hedin
- Department of Meteorology (MISU), Stockholm University, Stockholm, Sweden
- formerly at: Physical Sciences Division, SRI International, Menlo Park, California, USA
| | - Alexander A. Kutepov
- The Catholic University of America, Washington DC, USA
- NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - Stefan Noll
- Institute for Astro- and Particle Physics, University of Innsbruck, Innsbruck, Austria
- Institute of Physics, University of Augsburg, Augsburg, Germany
- German Remote Sensing Data Center (DFD), German Aerospace Center (DLR), Oberpfaffenhofen, Germany
| | - Peter A. Panka
- NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - Constantin Romanescu
- formerly at: Physical Sciences Division, SRI International, Menlo Park, California, USA
| | - Jérôme E. Thiebaud
- formerly at: Physical Sciences Division, SRI International, Menlo Park, California, USA
- Aeris Technologies, Redwood City, California, USA
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Liu Y, Peng J, Reppert K, Callahan S, Smith GP. Laser Measurements of the H Atom + Ozone Rate Constant at Mesospheric Temperatures. J Phys Chem A 2016; 120:3855-60. [PMID: 27193050 DOI: 10.1021/acs.jpca.6b02986] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The exothermic H + O3 reaction produces OH(v) Meinel band emissions, used to derive mesospheric H concentrations and chemical heating rates. We remeasured its rate constant to reduce its uncertainty and extended the measurements to lower mesospheric temperatures using modern laser-induced fluorescence (LIF) techniques. H atoms were produced by pulsed ultraviolet laser trace photolysis of O3, followed by reaction of O((1)D) with added H2. A second, delayed, frequency-mixed dye laser measured the reaction decay rate with the remaining ozone using LIF. We monitored either the H atom decay by two photon excitation at 205 nm and detection of red fluorescence, or the OH (v = 9) product time evolution with excitation of the B(2)Σ(+)-X(2)Π (0,9) band at 237 nm and emission in the blue B(2)Σ(+)-A(2)Σ(+) (0,7) band. By cooling the enclosed low pressure flow cell we obtained measurements from 140 to 305 K at 20 to 200 Torr in Ar. Small kinetic modeling corrections were made for secondary regeneration of H atoms. The results are consistent with the current NASA JPL recommendation for this rate constant and establish its extrapolation down to the lower temperatures of the mesosphere.
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Affiliation(s)
- Yingdi Liu
- SRI International , 333 Ravenswood Avenue, Menlo Park, California 94025, United States
| | - Jian Peng
- SRI International , 333 Ravenswood Avenue, Menlo Park, California 94025, United States
| | - Kelsey Reppert
- SRI International , 333 Ravenswood Avenue, Menlo Park, California 94025, United States
| | - Sara Callahan
- SRI International , 333 Ravenswood Avenue, Menlo Park, California 94025, United States
| | - Gregory P Smith
- SRI International , 333 Ravenswood Avenue, Menlo Park, California 94025, United States
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Bergmann K, Vitanov NV, Shore BW. Perspective: Stimulated Raman adiabatic passage: The status after 25 years. J Chem Phys 2015; 142:170901. [PMID: 25956078 DOI: 10.1063/1.4916903] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The first presentation of the STIRAP (stimulated Raman adiabatic passage) technique with proper theoretical foundation and convincing experimental data appeared 25 years ago, in the May 1st, 1990 issue of The Journal of Chemical Physics. By now, the STIRAP concept has been successfully applied in many different fields of physics, chemistry, and beyond. In this article, we comment briefly on the initial motivation of the work, namely, the study of reaction dynamics of vibrationally excited small molecules, and how this initial idea led to the documented success. We proceed by providing a brief discussion of the physics of STIRAP and how the method was developed over the years, before discussing a few examples from the amazingly wide range of applications which STIRAP now enjoys, with the aim to stimulate further use of the concept. Finally, we mention some promising future directions.
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Affiliation(s)
- Klaas Bergmann
- Fachbereich Physik und Forschungszentrum OPTIMAS, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Nikolay V Vitanov
- Department of Physics, St. Kliment Ohridski University of Sofia, James Bourchier 5 Blvd., 1164 Sofia, Bulgaria
| | - Bruce W Shore
- 618 Escondido Circle, Livermore, California 94550, USA
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Pradhan GB, Juanes-Marcos JC, Balakrishnan N, Kendrick BK. Chemical reaction versus vibrational quenching in low energy collisions of vibrationally excited OH with O. J Chem Phys 2013; 139:194305. [PMID: 24320324 DOI: 10.1063/1.4830398] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Quantum scattering calculations are reported for state-to-state vibrational relaxation and reactive scattering in O + OH(v = 2 - 3, j = 0) collisions on the electronically adiabatic ground state (2)A'' potential energy surface of the HO2 molecule. The time-independent Schrödinger equation in hyperspherical coordinates is solved to determine energy dependent probabilities and cross sections over collision energies ranging from ultracold to 0.35 eV and for total angular momentum quantum number J = 0. A J-shifting approximation is then used to compute initial state selected reactive rate coefficients in the temperature range T = 1 - 400 K. Results are found to be in reasonable agreement with available quasiclassical trajectory calculations. Results indicate that rate coefficients for O2 formation increase with increasing the OH vibrational level except at low and ultralow temperatures where OH(v = 0) exhibits a slightly different trend. It is found that vibrational relaxation of OH in v = 2 and v = 3 vibrational levels is dominated by a multi-quantum process.
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Affiliation(s)
- G B Pradhan
- Department of Chemistry, University of Nevada Las Vegas, Las Vegas, Nevada 89154, USA
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dos Santos SF, Balakrishnan N, Forrey RC, Stancil PC. Vibration-vibration and vibration-translation energy transfer in H2-H2 collisions: A critical test of experiment with full-dimensional quantum dynamics. J Chem Phys 2013; 138:104302. [DOI: 10.1063/1.4793472] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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