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View article: CCAT: Readout of over 10,000 280 GHz KIDs in Mod-Cam using RFSoC Electronics
CCAT: Readout of over 10,000 280 GHz KIDs in Mod-Cam using RFSoC Electronics Open
Over the past decade, kinetic inductance detectors (KIDs) have emerged as a viable superconducting technology for astrophysics at millimeter and submillimeter wavelengths. KIDs spanning 210 - 850 GHz across seven instrument modules will be…
View article: CCAT: Magnetic Sensitivity Measurements of Kinetic Inductance Detectors
CCAT: Magnetic Sensitivity Measurements of Kinetic Inductance Detectors Open
The CCAT Observatory is a ground-based submillimeter to millimeter experiment located on Cerro Chajnantor in the Atacama Desert, at an altitude of 5,600 meters. CCAT features the 6-meter Fred Young Submillimeter Telescope (FYST), which wil…
View article: CCAT: Mod-Cam Cryogenic Performance and its Impact on 280 GHz KID Array Noise
CCAT: Mod-Cam Cryogenic Performance and its Impact on 280 GHz KID Array Noise Open
The CCAT Observatory's Fred Young Submillimeter Telescope (FYST) is designed to observe submillimeter astronomical signals with high precision, using receivers fielding state-of-the-art kinetic inductance detector (KID) arrays. Mod-Cam, a …
View article: CCAT: LED Mapping and Characterization of the 280 GHz TiN KID Array
CCAT: LED Mapping and Characterization of the 280 GHz TiN KID Array Open
Prime-Cam, one of the primary instruments for the Fred Young Submillimeter Telescope (FYST) developed by the CCAT Collaboration, will house up to seven instrument modules, with the first operating at 280 GHz. Each module will include three…
View article: CCAT: a status update on the EoR-Spec instrument module for Prime-Cam
CCAT: a status update on the EoR-Spec instrument module for Prime-Cam Open
The Epoch of Reionization Spectrometer (EoR-Spec) is an upcoming Line\nIntensity Mapping (LIM) instrument designed to study the evolution of the early\nuniverse (z = 3.5 to 8) by probing the redshifted [CII] 158 $\\mu$m\nfine-structure lin…
View article: CCAT: nonlinear effects in 280 GHz aluminum kinetic inductance detectors
CCAT: nonlinear effects in 280 GHz aluminum kinetic inductance detectors Open
Prime-Cam, a first-generation science instrument for the Atacama-based Fred\nYoung Submillimeter Telescope, is being built by the CCAT Collaboration to\nobserve at millimeter and submillimeter wavelengths using kinetic inductance\ndetector…
View article: CCAT: Comparisons of 280 GHz TiN and Al Kinetic Inductance Detector Arrays
CCAT: Comparisons of 280 GHz TiN and Al Kinetic Inductance Detector Arrays Open
The CCAT Collaboration's six-meter Fred Young Submillimeter Telescope is scheduled to begin observing in the Chilean Atacama in 2025, targeting a variety of science goals throughout cosmic history. Prime-Cam is a 1.8-meter diameter cryosta…
View article: The BLAST Observatory: A Sensitivity Study for Far-IR Balloon-borne Polarimeters
The BLAST Observatory: A Sensitivity Study for Far-IR Balloon-borne Polarimeters Open
Sensitive wide-field observations of polarized thermal emission from interstellar dust grains will allow astronomers to address key outstanding questions about the life cycle of matter and energy driving the formation of stars and the evol…
View article: HTS Detector Magnet Demonstrator Based on a 3D-Printed Partially-Insulated Support Cylinder
HTS Detector Magnet Demonstrator Based on a 3D-Printed Partially-Insulated Support Cylinder Open
In this work, we extend the experimental demonstration of partially-insulated, ultra-radiation transparent detector\nmagnet technology based on a 3D-printed aluminium alloy support\nstructure containing 10% of silicon. This demonstrator ma…
View article: Characteristics of Aluminium-Stabilized HTS Detector Magnet Cable at 4 K and 5 T
Characteristics of Aluminium-Stabilized HTS Detector Magnet Cable at 4 K and 5 T Open
A high-temperature superconducting (HTS) cable for\nfuture particle detector magnets has been developed using a 99.3%\npure aluminium alloy as a stabilizer for the HTS. This HTS conductor features a stack of four ReBCO tapes (4 mm wide, Su…
View article: The BLAST Observatory: A Sensitivity Study for Far-IR Balloon-borne Polarimeters
The BLAST Observatory: A Sensitivity Study for Far-IR Balloon-borne Polarimeters Open
Sensitive wide-field observations of polarized thermal emission from interstellar dust grains will allow astronomers to address key outstanding questions about the life cycle of matter and energy driving the formation of stars and the evol…
View article: Self-protected high-temperature superconducting demonstrator magnet for particle detectors
Self-protected high-temperature superconducting demonstrator magnet for particle detectors Open
A high temperature superconducting (HTS) demonstration coil has been developed in the frame of the Experimental Physics department Research and Development program at CERN The magnet extends the recent experimental demonstration of alumini…
View article: MOSFET-based HTS flux pump
MOSFET-based HTS flux pump Open
We have developed a high-temperature superconducting (HTS) flux pump using high-power metal-oxide-semiconductor field-effect transistors (MOSFETs) for switching. For its primary coil, two commercial transformers are utilized, each consisti…
View article: Internal quantum efficiency of silicon photodetectors at ultraviolet wavelengths
Internal quantum efficiency of silicon photodetectors at ultraviolet wavelengths Open
We determine experimentally the internal quantum efficiency of a 3-element trap detector made of Hamamatsu S1337 photodiodes and of a predictable quantum efficient detector (PQED) over the wavelength range of 250–500 nm using an electrical…
View article: Impact ionization in silicon at low charge-carrier energies
Impact ionization in silicon at low charge-carrier energies Open
Photons absorbed in silicon produce electron–hole pairs, which can cause impact ionization and quantum yield larger than one. Reliable determination of quantum yield at low charge-carrier energies (<4 eV) has been challenging because ph…
View article: Absolute radiation pressure detector using a diamagnetically levitating test mass
Absolute radiation pressure detector using a diamagnetically levitating test mass Open
We have developed an absolute radiometer to measure laser power by means of radiation pressure in a closed control-loop configuration using diamagnetically levitated pyrolytic graphite as the soft spring and gravity as a contactless restor…
View article: Optical Power Scale Realization by Laser Calorimeter after 45 Years of Operation
Optical Power Scale Realization by Laser Calorimeter after 45 Years of Operation Open
To calibrate laser power and energy meters, the National Institute of Standards and Technology (NIST) uses several detector-based realizations of the scale for optical radiant flux; these realizations are appropriate for specific laser pow…
View article: High-accuracy room temperature planar absolute radiometer based on vertically aligned carbon nanotubes
High-accuracy room temperature planar absolute radiometer based on vertically aligned carbon nanotubes Open
We have developed a planar absolute radiometer for room temperature (PARRoT) that will replace the legacy C-series calorimeter as the free-space continuous-wave laser power detector standard at the National Institute of Standards and Techn…
View article: Room temperature laser power standard using a microfabricated, electrical substitution bolometer
Room temperature laser power standard using a microfabricated, electrical substitution bolometer Open
The design and performance of a room temperature electrical substitution radiometer for use as an absolute standard for measuring continuous-wave laser power over a wide range of wavelengths, beam diameters, and powers are described. The s…
View article: Development of 300 mW Background-Compensated Planar Absolute Radiometer Operating at Room Temperature
Development of 300 mW Background-Compensated Planar Absolute Radiometer Operating at Room Temperature Open
NIST’s C-series isoperibol calorimeters [1] operating at room temperature have been used as reference instruments in the laser power calibrations at NIST for over 50 years. These calorimeters operate from 100 μW to 300 mW with an expanded …
View article: Determining the shape of reflectance reference samples for curved surface reflectors
Determining the shape of reflectance reference samples for curved surface reflectors Open
Foils made of different materials are often used as reflective insulators. Many manufacturers aim to accurately measure their optical properties to estimate and improve their performance. However, flat reflectance reference samples used in…
View article: Cryostat setup for measuring spectral and electrical properties of light-emitting diodes at junction temperatures from 81 K to 297 K
Cryostat setup for measuring spectral and electrical properties of light-emitting diodes at junction temperatures from 81 K to 297 K Open
We introduce a cryostat setup for measuring fundamental optical and electrical properties of light-emitting diodes (LEDs). With the setup, the cryostat pressure and the LED properties of the forward voltage, junction temperature, and elect…
View article: FAILING MECHANISMS OF LED LAMPS
FAILING MECHANISMS OF LED LAMPS Open
We have aged 20 specimens of commercial LED lamps for 62 000 hours at typical room conditions since 2011.After 62 000 hours of continuous operation, the luminous fluxes of 9 specimens out of 20 were still above 70% of the initial value.Dur…
View article: Uncertainty analysis of total ozone derived from direct solar irradiance spectra in the presence of unknown spectral deviations
Uncertainty analysis of total ozone derived from direct solar irradiance spectra in the presence of unknown spectral deviations Open
We demonstrate the use of a Monte Carlo model to estimate the uncertainties in total ozone column (TOC) derived from ground-based direct solar spectral irradiance measurements. The model estimates the effects of possible systematic spectra…
View article: Relationships between junction temperature, electroluminescence spectrum and ageing of light-emitting diodes
Relationships between junction temperature, electroluminescence spectrum and ageing of light-emitting diodes Open
We have developed spectral models describing the electroluminescence spectra of AlGaInP and InGaN light-emitting diodes (LEDs) consisting of the Maxwell-Boltzmann distribution and the effective joint density of states. One spectrum at a kn…
View article: Monte Carlo method for determining uncertainty of total ozone derived from direct solar irradiance spectra: Application to Izaña results
Monte Carlo method for determining uncertainty of total ozone derived from direct solar irradiance spectra: Application to Izaña results Open
We demonstrate a Monte Carlo model to calculate the uncertainties of total ozone column, TOC, derived from ground-based directional solar spectral irradiance measurements. The model takes into account effects that correlations in the spect…
View article: Key comparison CCPR-K1.a as an interlaboratory comparison of correlated color temperature
Key comparison CCPR-K1.a as an interlaboratory comparison of correlated color temperature Open
We analyze the results of spectral irradiance key comparison CCPR-K1.a for correlated color temperature (CCT). For four participants out of 13, the uncertainties of CCT, calculated using traditional methods, not accounting for correlations…
View article: Setup for studying speckle noise of spectroradiometer diffusers in Earth observation applications
Setup for studying speckle noise of spectroradiometer diffusers in Earth observation applications Open
Diffusers in in-orbit spectroradiometers cause speckle under partially coherent solar radiation. A speckle pattern entering a spectroradiometer through a small slit creates systematic spectral deviations in measured spectra. We have develo…