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Search Publications by: David Long (Fed)

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Displaying 26 - 50 of 66

Improving the Retrieval of XCO2 from Total Carbon Column Network Solar Spectra

January 3, 2019
Author(s)
Joseph Mendonca, Kimberly Strong, Debra Wunch, Geoffrey Toon, David Long, Joseph T. Hodges, Vincent T. Sironneau
High-resolution absorption spectra of the a^1 ∆_g←X^3 Σ_g^- O2 band measured using cavity ring-down spectroscopy were fitted using the Voigt and speed-dependent Voigt line shapes. We found that the speed-dependent Voigt line shape was better able to model

Multiheterodyne Spectroscopy Using Multi-frequency Combs

May 13, 2017
Author(s)
David F. Plusquellic, Gerd A. Wagner, Adam Fleisher, David Long, Joseph T. Hodges
Near-IR dual frequency combs generated from waveform driven electro-optic phase modulators (EOMs) are used for high resolution studies in low pressure cells and for remote sensing from natural targets (Boulder Flatirons). Arbitrary waveform generators

Multiplexed sub-Doppler spectroscopy with an optical frequency comb

December 13, 2016
Author(s)
David A. Long, Adam J. Fleisher, David F. Plusquellic, Joseph T. Hodges
An optical frequency comb generated with an electro-optic phase modulator and a chirped radiofrequency waveform is used to perform saturation spectroscopy on the D1 and D2 transitions of atomic potassium. With a comb tooth spacing of 2 MHz and a bandwidth

Coherent cavity-enhanced dual-comb spectroscopy

May 4, 2016
Author(s)
Adam J. Fleisher, David A. Long, Zachary D. Reed, David F. Plusquellic, Joseph T. Hodges
Multiheterodyne spectroscopy performed with two stabilized optical frequency combs (OFCs) has shown great potential as a fast, accurate, and high-resolution substitute for existing interferometry methods that require lengthy integration times and precision

Mid-infrared molecular spectroscopy in the quantum noise limit

March 31, 2016
Author(s)
David A. Long, Adam J. Fleisher, Qingnan Liu, Joseph T. Hodges
A cavity ring-down spectrometer was used to reach the quantum noise limit in the mid-infrared spectral region. Quantum noise was observed not only in the individual ring-down decay events but also in the corresponding ensemble statistics with a magnitude

Frequency-agile, rapid scanning cavity ring-down spectroscopy (FARS-CRDS) measurements of the (30012) --(00001) near-infrared carbon dioxide band

April 3, 2015
Author(s)
David A. Long, Szymon S. Wojtewicz, Charles E. Miller, Joseph T. Hodges
We present new high accuracy measurements of the (30012)←(00001) CO¬2 band near 1575 nm recorded with a frequency-agile, rapid scanning cavity ring-down spectrometer. The resulting spectra were fit with the partially correlated, quadratic-speed-dependent

Observations of Dicke narrowing and speed dependence in air-broadened CO2 lineshape near 2.06 um

November 3, 2014
Author(s)
Thinh Q. Bui, David Long, Agata Cygan, Vincent T. Sironneau, Daniel Hogan, Priyanka M. Rapusinghe, Mitchio Okumura
Frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) was used to study CO2 lineshapes in the (20013)←(00001) band centered near 2.06 um. Two rovibrational transitions were chosen for this study to measure non-Voigt collisional effects for air

Multiheterodyne spectroscopy with optical frequency combs generated from a continuous-wave laser

May 1, 2014
Author(s)
David A. Long, Adam J. Fleisher, Kevin O. Douglass, Stephen E. Maxwell, Katarzyna E. Bielska, Joseph T. Hodges, David F. Plusquellic
Dual-drive Mach-Zehnder modulators were utilized to produce power-leveled optical frequency combs (OFCs) from a continuous-wave laser. The resulting OFCs contained up to fifty unique frequency components and spanned more than 200 GHz. Simple changes to the