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1. Time-resolved velocity and ion sound speed measurements from simultaneous bow shock imaging and inductive probe measurements

   https://doi.org/10.1063/5.0098823  

   Datta, R. ; Russell, D. R. ; Tang, I. ; Clayson, T. ; Suttle, L. G. ; Chittenden, J. P. ; Lebedev, S. V. ; Hare, J. D. ( October 2022 , Review of Scientific Instruments)

   We present a technique to measure the time-resolved velocity and ion sound speed in magnetized, supersonic high-energy-density plasmas. We place an inductive (“b-dot”) probe in a supersonic pulsed-power-driven plasma flow and measure the magnetic field advected by the plasma. As the magnetic Reynolds number is large ( R M > 10), the plasma flow advects a magnetic field proportional to the current at the load. This enables us to estimate the flow velocity as a function of time from the delay between the current at the load and the signal at the probe. The supersonic flow also generates a hydrodynamic bow shock around the probe, the structure of which depends on the upstream sonic Mach number. By imaging the shock around the probe with a Mach–Zehnder interferometer, we determine the upstream Mach number from the shock Mach angle, which we then use to determine the ion sound speed from the known upstream velocity. We use the sound speed to infer the value of [Formula: see text], where [Formula: see text] is the average ionization and T e is the electron temperature. We use this diagnostic to measure the time-resolved velocity and sound speed of a supersonic ( M S ∼ 8), super-Alfvénic ( M A ∼ 2) aluminum plasma generated during the ablation stage of an exploding wire array on the Magpie generator (1.4 MA, 250 ns). The velocity and [Formula: see text] measurements agree well with the optical Thompson scattering measurements reported in the literature and with 3D resistive magnetohydrodynamic simulations in GORGON. 

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2. Sulfur isotopes of sulfate measurements from a Greenland ice core (1200-1850) and volcanic gas measurements from various volcanoes and hot springs in Iceland

   https://doi.org/10.18739/A2N873162  

   Jongebloed, Ursula ; Alexander, Becky ; Cole-Dai, Jihong ; Schauer, Andrew ; Larrick, Carleigh ; Wood, Robert ; Fischer, Tobias ; Carn, Simon ; Salimi, Sara ; Edouard, Shana ; et al ( January 2022 , NSF Arctic Data Center)

   The Arctic is warming at almost four times the global rate. Cooling caused by anthropogenic aerosols has been estimated to offset sixty percent of greenhouse-gas-induced Arctic warming, but the contribution of aerosols to radiative forcing (RF) represents the largest uncertainty in estimating total RF, largely due to unknown preindustrial aerosol abundance. Here, sulfur isotope measurements in a Greenland ice core show that passive volcanic degassing contributes up to 66 ± 10% of preindustrial ice core sulfate in years without major eruptions. A state-of-the-art model indicates passive volcanic sulfur emissions influencing the Arctic are underestimated by up to a factor of three, possibly because many volcanic inventories do not include hydrogen sulfide emissions. Higher preindustrial volcanic sulfur emissions reduce modeled anthropogenic Arctic aerosol cooling by up to a factor of two (+0.11 to +0.29 W m-2 (watts per square meter)), suggesting that underestimating passive volcanic sulfur emissions has significant implications for anthropogenic-induced Arctic climate change. These data include sulfur isotopes of sulfate measurements from a Greenland ice core and volcanic gas measurements (CO2:S (carbon dioxide:sulfur) ratios) from various volcanoes and hot springs in Iceland. 

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3. Validation of two independent photogrammetric techniques for determining body measurements of gorillas: Photogrammetry and Body Measurements in Gorillas

   https://doi.org/10.1002/ajp.22511  

   Galbany, Jordi ; Stoinski, Tara S. ; Abavandimwe, Disier ; Breuer, Thomas ; Rutkowski, William ; Batista, Nicholas V. ; Ndagijimana, Felix ; McFarlin, Shannon C. ( April 2016 , American Journal of Primatology)
4. Series Resistance Measurements of Perovskite Solar Cells Using Jsc – Voc Measurements

   https://doi.org/10.1002/solr.201800378  

   Mundhaas, Noemi ; Yu, Zhengshan J. ; Bush, Kevin A. ; Wang, Hsin‐Ping ; Häusele, Jakob ; Kavadiya, Shalinee ; McGehee, Michael D. ; Holman, Zachary C. ( March 2019 , Solar RRL)
5. A New Instrument for Balloon‐Borne In Situ Aerosol Size Distribution Measurements, the Continuation of a 50 Year Record of Stratospheric Aerosols Measurements

   https://doi.org/10.1029/2022JD037485  

   Kalnajs, Lars E. ; Deshler, Terry ( December 2022 , Journal of Geophysical Research: Atmospheres)

   Profiles of stratospheric aerosol size distributions have been measured using balloon‐bornein situoptical particle counters, from Laramie, Wyoming (41°N) since 1971. In 2019, this measurement record transitioned to the Laboratory for Atmospheric and Space Physics (LASP) in Boulder, Colorado (40°N). The new LASP Optical Particle Counter (LOPC), the fourth generation of instruments used for this record, is smaller and lighter (2 kg) than prior instruments, measures aerosols with diameters ≥0.3–30 μm in up to 450 size bins, with a flow rate of 20 L min⁻¹. The improved size resolution enables the complete measurement of size distributions, and calculation of aerosol extinction without fittinga prioridistribution shapes. The higher flow provides the sensitivity required to measure super‐micron particles in the stratosphere. The LOPC has been validated against prior Wyoming OPCs, through joint flights, laboratory comparisons, and statistical comparisons with the Wyoming record. The agreement between instruments is generally within the measurement uncertainty of ±10%–20% in sizing and ±10% in concentration, and within ±40% for calculated aerosol moments. The record is being continued with balloon soundings every 2 months from Colorado, coordinated with measurements of aerosol extinction from the SAGE III instrument on the International Space Station. Comparisons of aerosol extinction from the remote andin situplatforms have shown good agreement in the stratosphere, particularly for wavelengths <755 nm and altitudes <25 km. For extinction wavelengths ≥1,021 nm and altitudes above 25 km SAGE III/International Space Station extinction has a low bias relative to thein situmeasurements, yet still within the ±40% uncertainty.

    

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