scholarly journals Scattering of adiabatically aligned molecules by nonresonant optical standing waves

2020 ◽  
Vol 6 (14) ◽  
pp. eaaz0682
Author(s):  
Lee Yeong Kim ◽  
Byung Gwun Jin ◽  
Tae Woo Kim ◽  
Ju Hyeon Lee ◽  
Bum Suk Zhao
Keyword(s):  
Standing Wave ◽  
Transverse Velocity ◽  
Translational Motion ◽  
Central Peak ◽  
Peak Position ◽  
Rotational State ◽  
Molecular Scattering ◽  
Optical Fields ◽  
Rotational States ◽  
State Dependent

We study the effect of rotational state–dependent alignment in the scattering of molecules by optical fields. CS2 molecules in their lowest few rotational states are adiabatically aligned and transversely accelerated by a nonresonant optical standing wave. The width of the measured transverse velocity distribution increases to 160 m/s with the field intensity, while its central peak position moves from 10 to −10 m/s. These changes are well reproduced by numerical simulations based on the rotational state–dependent alignment but cannot be modeled when ignoring these effects. Moreover, the molecular scattering by an off-resonant optical field amounts to manipulating the translational motion of molecules in a rotational state–specific way. Conversely, our results demonstrate that scattering from a nonresonant optical standing wave is a viable method for rotational state selection of nonpolar molecules.

scholarly journals Origin of the “odd” behavior in the ultraviolet photochemistry of ozone

2020 ◽  
Vol 117 (35) ◽  
pp. 21065-21069
Author(s):  
Shanyu Han ◽  
Carolyn E. Gunthardt ◽  
Richard Dawes ◽  
Daiqian Xie ◽  
Simon W. North ◽  
...  
Keyword(s):  
Quantum Theory ◽  
Selection Rule ◽  
Rotational Quantum Number ◽  
Rotational State ◽  
Isotopic Enrichment ◽  
State Distribution ◽  
Rotational States ◽  
Increasing Temperature ◽  
Full Quantum ◽  
Curve Crossing

The origin of the even–odd rotational state population alternation in the16O2(a1Δg) fragments resulting from the ultraviolet (UV) photodissociation of16O3, a phenomenon first observed over 30 years ago, has been elucidated using full quantum theory. The calculated16O2(a1Δg) rotational state distribution following the 266-nm photolysis of 60 K ozone shows a strong even–odd propensity, in excellent agreement with the new experimental rotational state distribution measured under the same conditions. Theory indicates that the even rotational states are significantly more populated than the adjacent odd rotational states because of a preference for the formation of the A′ Λ-doublet, which can only occupy even rotational states due to the exchange symmetry of the two bosonic16O nuclei, and thus not as a result of parity-selective curve crossing as previously proposed. For nonrotating ozone, its dissociation on the excited B1A′ state dictates that only A′ Λ-doublets are populated, due to symmetry conservation. This selection rule is relaxed for rotating parent molecules, but a preference still persists for A′ Λ-doublets. The A′′/A′ ratio increases with increasing ozone rotational quantum number, and thus with increasing temperature, explaining the previously observed temperature dependence of the even–odd population alternation. In light of these results, it is concluded that the previously proposed parity-selective curve-crossing mechanism cannot be a source of heavy isotopic enrichment in the atmosphere.

Rotational state-dependent mixings between resonance states of vibrationally highly excited DCO (X̃ 2A′)

2004 ◽  
Vol 120 (22) ◽  
pp. 10530-10542 ◽  
Author(s):  
J. Wei ◽  
A. Tröllsch ◽  
C. Tesch ◽  
F. Temps
Keyword(s):  
Rotational State ◽  
Resonance States ◽  
State Dependent

scholarly journals SUBARU near-infrared multi-color images of Class II Young Stellar Object, RNO91

2006 ◽  
Vol 2 (S237) ◽  
pp. 447-447
Author(s):  
Satoshi Mayama ◽  
Motohide Tamura ◽  
Masahiko Hayashi
Keyword(s):  
Near Infrared ◽  
Infrared Imaging ◽  
Infrared Camera ◽  
Central Peak ◽  
Class Ii ◽  
Peak Position ◽  
Infrared Light ◽  
Molecular Outflows ◽  
The North ◽  
Optical Images

AbstractRNO91 is class II source currently in a transition phase between a protostar and a main-sequence star. It is known as a source of complex molecular outflows. Previous studies suggested that RNO91 was associated with a reflection nebula, a CO outflow, shock-excited H2 emission, and disk type structure. But the geometry of RNO91, especially its inner region, is not well confirmed yet. High resolution imaging is needed to understand the nature of RNO91 and its interaction with outflow. Thus, we conducted near-infrared imaging observations of RNO91 with the infrared camera CIAO mounted on the Subaru 8.2-m Telescope. We presented JHK band and optical images which resolved a complex asymmetrical circumstellar structure. We examined the color of RNO91 nebula and compared the geometry of the system suggested by our data with that already proposed on the basis of other studies. Our main results are as follows; 1. The K-band images show significant halo emission detected within ~2″ around the peak position while less halo emission is seen in shorter wavelength images such as J and optical. The nebula appears to become more circular and more diffuse with increasing wavelengths. The cut-off at 300AU derived from our radial surface brightness is consistent with the size of the polarization disk suggested by Draper & Tadhunter (1993). These consistencies indicate that this optically thick region is attributed to a disk-like structure.2. At J and optical, several bluer knot-like structures are detected around and beyond the halo emission. These bluer knots seen in our images are comparable to the size of the envelope detected in HCO+ emission surrounding RNO91 (Lee & Ho 2005). It is thus natural to suggest that these bluer knots are the near-infrared light scattered by an envelope structure which is disrupted by molecular outflows.3. The pseudo-true color composite image has an appearance of arc-shaped emission extending to the north and to the east through RNO91. On the counter part of this arc-shaped structure, the nebula appears to become more extended to the southwest from the central peak position in J band and optical images. We interpret these whole structures as a bottom of bipolar cavity seen relatively edge-on opening to the north and south directions.

Rotational state-dependent attachment of He atoms to cold molecular ions: An action spectroscopic scheme for rotational spectroscopy

2017 ◽  
Vol 332 ◽  
pp. 67-78 ◽  
Author(s):  
Sandra Brünken ◽  
Lars Kluge ◽  
Alexander Stoffels ◽  
Jesús Pérez-Ríos ◽  
Stephan Schlemmer
Keyword(s):  
Molecular Ions ◽  
Rotational State ◽  
Rotational Spectroscopy ◽  
State Dependent

Rotational-State-Dependent Dispersion of Molecules by Pulsed Optical Standing Waves

2015 ◽  
Vol 115 (22) ◽  
Author(s):  
Xing Nan Sun ◽  
Lee Yeong Kim ◽  
Bum Suk Zhao ◽  
Doo Soo Chung
Keyword(s):  
Standing Waves ◽  
Rotational State ◽  
State Dependent

On the problem of rotational-state-dependent molecule–surface interaction: Relaxation, accommodation and trapping at low J

2000 ◽  
Vol 112 (19) ◽  
pp. 8680-8686 ◽  
Author(s):  
A. Yu. Pankov ◽  
S. Yu. Krylov ◽  
E. J. van Duijn ◽  
L. J. F. Hermans
Keyword(s):  
Surface Interaction ◽  
Rotational State ◽  
State Dependent ◽  
Molecule Surface

scholarly journals Characterization of the Rotation of Cometary Nuclei

1991 ◽  
Vol 116 (2) ◽  
pp. 690-721 ◽  
Author(s):  
Michael J. S. Belton
Keyword(s):  
Time Series ◽  
Cometary Nucleus ◽  
Rotational State ◽  
Point Of View ◽  
Data Sets ◽  
Primary Methods ◽  
Cometary Nuclei ◽  
Rotational States ◽  
Future Data

Abstract.I review the primary methods used to determine the spin state of cometary nuclei and the pitfalls and successes experienced in their use. There are in excess of 60 reported determinations of rotational periodicities, but only a few (~4) appear to be reliable, and even these do not necessarily fully describe the true rotational state. An adequate rotational ephemeris is not, at present, available for a single cometary nucleus.Because recent studies indicate that active cometary nuclei could be in excited spin states, I also review the theory of rigid body rotation from the point of view of remote (astronomical) observers, covering what is known of the effects of nutation on lightcurves, the influence of torques induced by jet activity, and the effects of internal energy and mass dissipation, and nuclear splitting.The available knowledge on rotation for 8 comets, including P/Halley, is reviewed. Outstanding questions that need early resolution are: (1) Can a consensus be achieved on the rotational state of P/Halley? (2) Is it possible to accurately determine the amplitude of the transverse non-gravitational force associated with rotation? (3) Are the orientations of fan-like comas a valid indicator of the orientation of the spin vector – can definitive observational checks be made in a few cases?Improved observational and interpretational techniques are needed to advance this field. Improved time-series and zero-date analyses are needed to connect existing and future data sets and to search for multiple periodicities in cometary lightcurves; improved sampling and extension of time-series observations with moderate- and large-aperture telescopes at good sites is needed; near-simultaneous photometric and radiometric observations made when cometary activity is low are particularly significant; well-sampled time-series imaging of near-nuclear phenomena (together with adequate software to analyze them) is essential to diagnose rotational states if nutation is present.

scholarly journals The Spectrum of the Molecular Eigenstates of Pyrazine and the Reconstruction of Decays of Rotational States of the 1B3u (0–0) Transition of Pyrazine

1983 ◽  
Vol 2 (3-4) ◽  
pp. 77-89 ◽  
Author(s):  
Barend J. van der Meer ◽  
Harry Th. Jonkman ◽  
Jan Kommandeur
Keyword(s):  
Molecular Beam ◽  
Narrow Band ◽  
Rotational State ◽  
Fast Component ◽  
Doppler Width ◽  
Rotational States ◽  
Narrow Band Laser

The spectrum of the molecular eigenstates (ME) belonging to the various rotational members of the 1B3u (0–0) transition of pyrazine was measured with a very narrow band laser in a molecular beam with a Doppler width of 30 MHz.It is shown that, when the ME's belonging to a single rotational state are Fourier-transformed, the beating decays of these states are obtained. A problem is constituted by the lack of a fast component in these reconstructions, while it is observed in experiments on higher J-states.

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