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1. Spectral calibration of the MethaneAIR instrument

   https://doi.org/10.5194/amt-14-3737-2021  

   Staebell, Carly; Sun, Kang; Samra, Jenna; Franklin, Jonathan; Chan Miller, Christopher; Liu, Xiong; Conway, Eamon; Chance, Kelly; Milligan, Scott; Wofsy, Steven (January 2021, Atmospheric Measurement Techniques)

   Abstract. MethaneAIR is the airborne simulator of MethaneSAT, an area-mapping satellite currently under development with the goal of locating and quantifying large anthropogenic CH4 point sources as well as diffuse emissions at the spatial scale of an oil and gas basin. Built to closely replicate the forthcoming satellite, MethaneAIR consists of two imaging spectrometers. One detects CH4 and CO2 absorption around 1.65 and 1.61 µm, respectively, while the other constrains the optical path in the atmosphere by detecting O2 absorption near 1.27 µm. The high spectral resolution and stringent retrieval accuracy requirements of greenhouse gas remote sensing in this spectral range necessitate a reliable spectral calibration. To this end, on-ground laboratory measurements were used to derive the spectral calibration of MethaneAIR, serving as a pathfinder for the future calibration of MethaneSAT. Stray light was characterized and corrected for through fast-Fourier-transform-based Van Cittert deconvolution. Wavelength registration was examined and found to be best described by a linear relationship for both bands with a precision of ∼ 0.02 spectral pixel. The instrument spectral spread function (ISSF), measured with fine wavelength steps of 0.005 nm near a series of central wavelengths across each band, was oversampled to construct the instrument spectral response function (ISRF) at each central wavelength and spatial pixel. The ISRFs were smoothed with a Savitzky–Golay filter for use in a lookup table in the retrieval algorithm. The MethaneAIR spectral calibration was evaluated through application to radiance spectra from an instrument flight over the Colorado Front Range. 

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2. The Black Hole Explorer cryocooling instrument

   https://doi.org/10.1117/12.3019449  

   Rana, Hannah; Akiyama, Kazunori; Canavan, Edgar R; DiPirro, Michael J; Freeman, Mark; Galison, Peter; Grimes, Paul K; Honma, Mareki; Houston, Janice; Johnson, Michael; et al (August 2024, SPIE)

   Coyle, Laura E; Perrin, Marshall D; Matsuura, Shuji (Ed.)
3. The HIBEAM instrument at the European spallation source

   https://doi.org/10.1088/1361-6471/adc8c2  

   Santoro, V; Milstead, D; Fierlinger, P; Snow, W M; Amaral, J; Barrow, J; Bartis, M; Bentley, P; Björk, L; Brooijmans, G; et al (April 2025, Journal of Physics G: Nuclear and Particle Physics)

   Abstract The European spallation source (ESS) will be the world’s brightest neutron source and will open a new intensity frontier in particle physics. The HIBEAM collaboration aims to exploit the unique potential of the ESS with a dedicated ESS instrument for particle physics which offers world-leading capability in a number of areas. The HIBEAM program includes the first search in thirty years for free neutrons converting to antineutrons and searches for sterile neutrons, ultralight axion dark matter and nonzero neutron electric charge. This paper outlines the capabilities, design, infrastructure, and scientific potential of the HIBEAM program, including its dedicated beamline, neutron optical system, magnetic shielding and control, and detectors for neutrons and antineutrons. Additionally, we discuss the long-term scientific exploitation of HIBEAM, which may include measurements of the neutron electric dipole moment and precision studies of neutron decays. 

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4. Instrument Simulator and Data Reduction Pipeline for the iLocater Spectrograph

   https://doi.org/10.1088/1538-3873/aaf278  

   Bechter, Eric B.; Bechter, Andrew J.; Crepp, Justin R.; Crass, Jonathan; King, David (February 2019, Publications of the Astronomical Society of the Pacific)
5. Instrument-Armed Bandits

   Kallus, Nathan (January 2018, Proceedings of Machine Learning Research)

   We extend the classic multi-armed bandit (MAB) model to the setting of noncompliance, where the arm pull is a mere instrument and the treatment applied may differ from it, which gives rise to the instrument-armed bandit (IAB) problem. The IAB setting is relevant whenever the experimental units are human since free will, ethics, and the law may prohibit unrestricted or forced application of treatment. In particular, the setting is relevant in bandit models of dynamic clinical trials and other controlled trials on human interventions. Nonetheless, the setting has not been fully investigate in the bandit literature. We show that there are various and divergent notions of regret in this setting, all of which coincide only in the classic MAB setting. We characterize the behavior of these regrets and analyze standard MAB algorithms. We argue for a particular kind of regret that captures the causal effect of treatments but show that standard MAB algorithms cannot achieve sublinear control on this regret. Instead, we develop new algorithms for the IAB problem, prove new regret bounds for them, and compare them to standard MAB algorithms in numerical examples. 

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