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Related papers: Design and Implementation of the wvrgcal Program

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The calibration and traceability of high resolution frequency modulated continuous wave (FMCW) ladar sources is a requirement for their use in length and volume metrology. We report the calibration of a FMCW ladar length measurement system…

Optics · Physics 2015-03-03 Ana Baselga Mateo , Zeb W. Barber

In a joint effort, MeteoSwiss and Deutscher Wetterdienst (DWD) address the need for improving the initial state of the atmospheric boundary layer (ABL) by exploiting ground-based profiling observations that aim to fill the existing…

The ALMA interferometer, with its unprecedented combination of high-sensitivity and high-angular resolution, allows for (sub-)mm wavelength mapping of protostellar systems at Solar System scales. Astrochemistry has benefited from imaging…

An upgrade to the ATLAS silicon tracker cooling control system may require a change from C3F8 (octafluoro-propane) evaporative coolant to a blend containing 10-25% of C2F6 (hexafluoro-ethane). Such a change will reduce the evaporation…

The aim of this study is to demonstrate how the logarithmic millimeter continuum gradient observed using the Atacama Large Millimeter/submillimeter Array (ALMA) may be used to estimate optical thickness in the solar atmosphere. We discuss…

Solar and Stellar Astrophysics · Physics 2019-05-01 Andrew S. Rodger , Nicolas Labrosse , Sven Wedemeyer , Mikolaj Szydlarski , Paulo J. A. Simões , Lyndsay Fletcher

We present a pilot, untargeted extragalactic carbon monoxide (CO) emission-line survey using ALMACAL, a project utilizing ALMA calibration data for scientific purposes. In 33 deep (Texp > 40 min) ALMACAL fields we report six CO…

We describe the design, construction, and initial validation of the variable-delay polarization modulator (VPM) designed for the PIPER cosmic microwave background polarimeter. The VPM modulates between linear and circular polarization by…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 David T. Chuss , Joseph R. Eimer , Dale J. Fixsen , James Hinderks , Alan J. Kogut , Justin Lazear , Paul Mirel , Eric Switzer , George M. Voellmer , Edward J. Wollack

Experiments in Atomic, Molecular, and Optical (AMO) physics require precise and accurate control of digital, analog, and radio frequency (RF) signals. We present a control hardware based on a field programmable gate array (FPGA) core which…

FRAM - F/(Ph)otometric Robotic Atmospheric Monitor is the latest addition to the atmospheric monitoring instruments of the Pierre Auger Observatory. An optical telescope equipped with CCD camera and photometer, it automatically observes a…

Characterizing the variability of the extragalactic sources used for calibration in the Atacama Large Millimeter/Sub-millimeter Array (ALMA) is key to assess the flux scale uncertainty of science observations. To this end, we model the…

Instrumentation and Methods for Astrophysics · Physics 2019-08-12 A. E. Guzmán , C. Verdugo , H. Nagai , Y. Contreras , G. Marinello , R. Kneissl , K. Nakanishi , J. Ueda

This paper investigates the performance of the thermal wave radar imaging technique in low-power vibrothermography, so-called vibro-thermal wave radar (VTWR), for non-destructive inspection of composites. VTWR is applied by binary phase…

Applied Physics · Physics 2021-05-11 Saeid Hedayatrasa , Joost Segers , Gaétan Poelman , Wim Van Paepegem , Mathias Kersemans

The World Space Observatory - Ultraviolet (WSO-UV) space telescope is equipped with high dispersion (55,000) spectrographs working in the 1150-3100 {\AA} spectral range. To evaluate the impact of the design on the scientific objectives of…

Instrumentation and Methods for Astrophysics · Physics 2017-06-13 Pablo Marcos-Arenal , Ana I. Gómez de Castro , Belén Perea Abarca , Mikhail Sachkov

Atmospheric water vapor is the main limiting factor of atmospheric transparency in the mm and submm wavelength spectral windows. Thus, dry sites are needed for the installation and successful operation of radio astronomy observatories…

Wavefront correction and beam tracking are critical in applications such as long-range imaging through turbulence and free-space optical communication. For instance, adaptive optics systems are employed to correct wavefront distortions…

The work analyzes existing methods for increasing the accuracy of determining weekend navigation parameters of unmanned underwater vehicles. It is proposed to retrofit the navigation system with an additional hydrodynamic tilt unit, which…

Systems and Control · Electrical Eng. & Systems 2023-12-14 A. N. Grekov , M. A Pasynkov , . S. S. Peliushenko

Wide-area synchrophasor ambient measurements provide a valuable data source for real-time oscillation mode monitoring and analysis. This paper introduces a novel method for identifying inter-area oscillation modes using wide-area ambient…

Signal Processing · Electrical Eng. & Systems 2021-03-03 Shutang You

The exoALMA Large Program was designed to search for subtle kinematic deviations from Keplerian motion, indicative of embedded planets, in high angular and spectral resolution Band 7 observations of $^{12}$CO, $^{13}$CO and CS emission from…

We demonstrate phase correction of 3 mm VLBI observations using the scanning 18 GHz to 26 GHz water vapour radiometer at Effelsberg and we demonstrate an absolute accuracy of 15 mm in zenith path delay by comparing with GPS and radiosondes.…

Astrophysics · Physics 2007-05-23 A. L. Roy , H. Rottmann , U. Teuber , R. Keller

The Atacama Large Millimeter/submillimeter Array (ALMA) is the world's leading instrument for high-resolution imaging of the 0.3 to 10 mm wavelength sky. This interferometer exemplifies successful international collaboration even down to…

Instrumentation and Methods for Astrophysics · Physics 2025-03-12 Tom Bakx , John Conway