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We discuss a simple, linear, zero-delay implementation of spectral shearing interferometry for amplitude and phase characterization of optical frequency comb sources and arbitrary waveforms. We demonstrate this technique by characterizing…

Gas samples relevant to health and environment typically contain a plethora of molecular species that span a huge concentration dynamic range. High-concentration molecules impose a strong absorption background that hinders robust…

Optics · Physics 2024-06-07 Qizhong Liang , Apoorva Bisht , Andrew Scheck , Peter G. Schunemann , Jun Ye

2D and 4D transverse phase-space of a low-energy ion-beam is measured with two of the most common emittance scanners. The article covers the description of the installation, the setup, the settings, the experiment and the benchmark of the…

Accelerator Physics · Physics 2023-01-25 F Osswald , T Durand , M Heine , J Michaud , F Poirier , J C Thomas , E Traykov

It is now known that the emission from radio pulsars can vary over a wide range of timescales, from fractions of seconds to decades. However, it is not yet known if long- and short-term emission variability are caused by the same physical…

High Energy Astrophysical Phenomena · Physics 2019-08-28 Paul Brook , Aris Karastergiou , Simon Johnston

Beamforming is an imaging tool for the investigation of aeroacoustic phenomena and results in high dimensional data that is broken down to spectra by integrating spatial Regions Of Interest. This paper presents two methods that enable the…

Sound · Computer Science 2021-09-29 Armin Goudarzi , Carsten Spehr , Steffen Herbold

Sensors are routinely mounted on robots to acquire various forms of measurements in spatio-temporal fields. Locating features within these fields and reconstruction (mapping) of the dense fields can be challenging in resource-constrained…

Robotics · Computer Science 2019-01-29 Martin Asenov , Marius Rutkauskas , Derryck Reid , Kartic Subr , Subramanian Ramamoorthy

Future imaging spectrometers will increase data volumes by orders of magnitude, requiring automated detection of trace gas point sources. We present a fully automated framework that combines machine learning-based morphological analysis…

We have built a frequency chain which enables to measure the absolute frequency of a laser emitting in the 28-31 THz frequency range and stabilized onto a molecular absorption line. The set-up uses an optical frequency comb and an…

Mitigating anthropogenic methane sources is one of the most cost-effective levers to slow down global warming. While satellite-based imaging spectrometers, such as EMIT, PRISMA, and EnMAP, can detect these point sources, current methane…

Infrared spectroscopy is a powerful tool for basic and applied science. The molecular spectral fingerprints in the 3 um to 20 um region provide a means to uniquely identify molecular structure for fundamental spectroscopy, atmospheric…

Global greenhouse gas emissions estimates are essential for monitoring and mitigation planning. Yet most datasets lack one or more characteristics that enhance their actionability, such as accuracy, global coverage, high spatial and…

Optical emission spectroscopy from a small-volume, 5 uL, atmospheric pressure RF-driven helium plasma was used in conjunction with Partial Least Squares Discriminant Analysis (PLS-DA) for the detection of trace concentrations of methane…

Plasma Physics · Physics 2022-07-12 Tahereh Shah Mansouri , Hui Wang , Davide Mariotti , Paul Maguire

Broadband dual-comb spectroscopy has attracted increasing interests due to its unique advantages in high spectral resolution, fast detection, and so on. Although the dual-comb technique is relatively mature in the infrared wavelengths, it…

Utilization of directional antennas is a promising solution for efficient spectrum sensing and accurate source localization and tracking. Spectrum sensors equipped with directional antennas should constantly scan the space in order to track…

Signal Processing · Electrical Eng. & Systems 2019-05-23 Mohsen Joneidi , Hassan Yazdani , Azadeh Vosoughi , Nazanin Rahnavard

At present, a two-phase argon detector is being developed in our laboratory for dark matter search and low-energy neutrino experiments. To calibrate its energy scale a $^{109}$Cd gamma-ray source was used. In this work a detailed emission…

Instrumentation and Detectors · Physics 2018-06-01 A. Bondar , A. Buzulutskov , A. Dolgov , A. Legkodymov , V. Nosov , V. Oleynikov , V. Porosev , E. Shemyakina , A. Sokolov

The article addresses the problem of detecting presence and location of a small low emission source inside of an object, when the background noise dominates. This problem arises, for instance, in some homeland security applications. The…

Statistics Theory · Mathematics 2015-05-28 Xiaolei Xun , Bani Mallick , Raymond J. Carroll , Peter Kuchment

The remote sensing of gases in complex mixtures at atmospheric pressure is a challenging problem and much attention has been paid to it. The most fundamental difference between this application and highly successful astrophysical and upper…

Chemical Physics · Physics 2016-11-18 Frank C. De Lucia , Douglas T. Petkie , Henry O. Everitt

We report on a comb-locked cavity ring-down spectrometer developed for high-precision, SI-traceable, molecular spectroscopy of air-broadened CO2 gas samples. The experimental setup relies on the use of a singly-resonant optical parametric…

The characterization of Earth-like exoplanets and precision tests of cosmological models using next-generation telescopes such as the ELT will demand precise calibration of astrophysical spectrographs in the visible region, where stellar…

We present a compact and stable dual-wavelength laser source for onboard atom interferometry with two different atomic species. It is based on frequency-doubled telecom lasers locked on a femtosecond optical frequency comb. We take…