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F K. Tchana, M. Ngom, Agnes Perrin, Jean-Marie Flaud, Walter J. Lafferty, S. A. Ndiaye, El. A. Ngum
Absolute individual line intensities of numerous transitions of the fundamental ν2 and ν10 bands of oxirane (ethylene oxide, c-C2H4O) have been measured in the 1420-1560 cm-1 region using seven high- resolution Fourier transform spectra recorded at 0.002
Walter J. Lafferty, Jean-Marie Flaud, Fridolin Kwabia, A. Perrin, M. Ngom
Seven Fourier transform spectra of the ν3 band of oxirane (ethylene oxide) have been recorded with different pressures and used to derive individual line intensities. These line intensities were satisfactorily fit leading to accurate transition moment
Omid Noroozian, John A. Mates, Douglas A. Bennett, Justus A. Brevik, Joseph W. Fowler, Jiansong Gao, Robert D. Horansky, Kent D. Irwin, Daniel R. Schmidt, Joel N. Ullom, Zhao Kang
We demonstrate the first gamma-ray spectroscopy with a microwave-multiplexed two-pixel TES(transition-edge sensor) array. We measured a $^{153}$Gd photon source and achieved an energy resolution of 63 eV full-width-at-half-maximum (FWHM) at 97 keV and an
A. Cygan, S. Wojtewicz, J. Domyslawska, Piotr Maslowski, Katarzyna E. Bielska, M. Piwinski, K. Stec, R.S. Trawinski, F Ozimek, C. Radzewicz, Hisashi Abe, T. Ido, Joseph T. Hodges, D Lisak, R. Ciurylo
A review of recent experiments involving a newly developed Pound-Drever-Hall-locked frequency-stabilized cavity ring-down spectroscopy (PDH-locked FS-CRDS) system is presented. By comparison to standard FS-CRDS, the PDH lock of the probe laser to the ring
Graphical representations are presented for variation along the steepest-descent internal-rotation path in methanol of the normal mode frequencies and their associated expansion coefficients in several sets of internal coordinates and in Cartesian atomic
Edwin J. Heilweil, Christopher J. Stromberg, Melissa Johnson, James Thuman, Roger G. Letterman, Webster E. Charles
Model compounds that structurally mimic the hydrogen-producing active site of [FeFe] hydrogenases have been explored. In order to explore potential ground-state electronic structure effects on reaction mechanisms compared to hexacarbonyl derivatives, the
Kevin O. Douglass, Stephen Maxwell, Gar W. Truong, Roger D. van Zee, Joseph T. Hodges, David Long, David F. Plusquellic
A method is reported for performing fast optical frequency scans over a bandwidth of 36.9 GHz and at a sweep rate of 40 kHz using a single second-order sideband from an electro-optic phase modulator driven by an arbitrary waveform generator. Single
Before the discovery of graphene, many versions of a bottom-up fullerene formation mechanism had been advanced starting with carbide (C2) that forms small carbon cluster chains and rings. However, in recent years evidence is emerging suggesting a top
Arsenic has been measured in food and food supplement Standard Reference Materials by neutron activation analysis for the purpose of value-assigning As mass fractions and assessing homogeneity. Instrumental neutron activation analysis (INAA) has been used
We investigate linear and nonlinear Faraday effects in a room-temperature, coherently driven four-level active- Raman-gain (ARG) medium. By using the multiple-scale method, we derive two nonlinear coupled envelope equations governing the dynamics of left-
David A. Long, Gar Wing Truong, Roger D. van Zee, David F. Plusquellic, Joseph T. Hodges
We present ultra-sensitive measurements of molecular absorption using frequency-agile rapid scanning, cavity-ring down spectroscopy with an external-cavity diode laser. A microwave source that drives an electro-optic phase modulator with a bandwidth of 20
James Radney, Xiaofei Ma, Keith A. Gillis, Michael R. Zachariah, Joseph T. Hodges, Christopher D. Zangmeister
The optical properties of atmospheric aerosols vary widely, being dependent upon particle composition, morphology and mixing state. This diversity and complexity of aerosols motivates measurement techniques that can discriminate and quantify a variety of
Signatures of multi-keV LMN dielectronic resonances in highly-charged 3dn ions of tungsten were detected in the intensity ratios of extreme-ultraviolet magnetic-dipole lines within ground configurations. The measurements were performed with an electron
Basudev Lahiri, Glenn E. Holland, Vladimir A. Aksyuk, Andrea Centrone
The collective oscillation of conduction electrons, responsible for the LSPRs, enables engineering nanomaterials by tuning their optical response from the visible to THz as a function of nanostructure size, shape and environment. While theoretical
Greg B. Rieker, Fabrizio R. Giorgetta, William C. Swann, Ian R. Coddington, Laura C. Sinclair, Christopher L. Cromer, Esther Baumann, Alexander M. Zolot, Nathan R. Newbury
Frequency-comb spectroscopy in the near-infrared is used to measure atmospheric CO2 and H2O concentrations over a 2-km outdoor open-air path. This technique shows promise for measurements over length scales between point sensors and satellite systems.
John D. Gillaspy, Dmitry D. Osin, Yuri Ralchenko, Joseph Reader, S A. Blundell
The NIST electron beam ion trap (EBIT) was used to measure the D1 (3s-3p1/2) and D2 (3s-3p3/2) transitions in Na-like ions of xenon, barium, samarium, gadolinium, dysprosium, erbium, tungsten, platinum, and bismuth. New relativistic many-body perturbation
A program, called PAM_C2v_2tops, for fitting the high-resolution torsion-rotation spectra of molecules with two equivalent methyl rotors and C2v symmetry at equilibrium is described and applied to the spectrum of acetone [(CH3)2CO]. The G36 permutation
Vladimir L. Orkin, Victor Khamaganov, E. E. Kasimovskaya, A G. Guschin
Rate constants for the gas phase reactions of OH radicals with three partially halogenated alkanes, CHCl3 (kMC), CHFClCFCl2 (k122a), and CH2CFCl2 (k132c), were measured using a discharge flow electron paramagnetic resonance technique over the temperature
buchanan Evan, Patrick Walsh, David F. Plusquellic, Timothy Zwier
Vibrationally and rotationally resolved electronic spectra of 1,2-diphenoxyethane (C6H5-O-CH2-CH2-O-C6H5) are reported for the isolated molecule under jet-cooled conditions. The spectra demonstrate that the two excited surfaces are within a few cm-1 of one
Nathan R. Newbury, Esther Baumann, Ian R. Coddington, Fabrizio R. Giorgetta, Greg B. Rieker, Laura C. Sinclair, William C. Swann, Alexander M. Zolot
Frequency combs have enabled a wide range of applications because of their unique combination of coherence and broad bandwidth. The comb provides 100,000's of comb teeth at precise, well-known optical frequencies that can support broadband accurate
Jeremie B. Courtois, Katarzyna E. Bielska, Joseph T. Hodges
We present a technique called differential cavity ring-down spectroscopy (D-CRDS) for reducing etaloning effects in a ring-down spectrometer. The method relies on alternately measuring and then subtracting intra-cavity losses associated with pairwise TEM00
Current methods of critical evaluation of wavelengths, energy levels, and transition probabilities for atoms and atomic ions at the National Institute of Standards and Technology are summarized.
Lu Deng, Edward W. Hagley, R Q. Wang, Charles W. Clark
Nonlinear optics has come a long way since the laser. This article reviews recent progress in coherent light-matter wave mixing and introduces some new concepts that will reframe future research directions.
Gar W. Truong, Kevin O. Douglass, Stephen E. Maxwell, Roger D. van Zee, David F. Plusquellic, Joseph T. Hodges, David A. Long
Challenging applications in trace gas analyses require high precision and acquisition rates.1-4 Many continuous-wave laser spectroscopy techniques exhibit significant sensitivity and potential;5 however, their scanning rates are slow because they rely upon
In this paper we revisit, with pedagogical emphasis for high-resolution spectroscopists, some presently existing discussions of phase factors for fixed-nuclei electronic wavefunctions in the Jahn-Teller problem. We give explicit examples, for a symmetric