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#hep

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Rxiv mechanobio

📰 "Dielectric Properties of Single Crystal Calcium Tungstate"
arxiv.org/abs/2507.21662 #Cond-Mat.Mtrl-Sci #Physics.App-Ph #Dynamics #Quant-Ph #Hep-Ex #Cell

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arXiv.orgDielectric Properties of Single Crystal Calcium TungstateThis investigation employed microwave whispering gallery mode (WGM) analysis to characterize the dielectric properties of a cylindrical, single-crystal sample of calcium tungstate (CaWO$_4$). Through investigation of quasi-transverse\hyp{}magnetic and quasi-transverse\hyp{}electric mode families, we can assess loss mechanisms and relative permittivity from room temperature down to cryogenic conditions. We report the biaxial permittivity values of $ε_{||} = 9.029 \pm 0.09$ and $ε_{\perp} = 10.761 \pm 0.11$ at $295$ K, and $ε_{||} = 8.797 \pm 0.088$ and $ε_{\perp} = 10.442 \pm 0.104$ at $4$ K. Components are denoted with respect to the c\hyp{}axis of the crystal unit cell. The parallel component agrees well with the published literature at MHz frequencies; however, the perpendicular component is $4.8$\% lower. The WGM technique offers greater precision, with accuracy limited primarily by the uncertainty in the crystal's dimensions. WGMs also serve as sensitive probes of lattice dynamics, enabling monitoring of temperature-dependent loss mechanisms. At room temperature, the measured loss tangents were $\tanδ_{||}^{295,\mathrm{K}} = (4.1 \pm 1.4) \times 10^{-5}$ and $\tanδ_{\perp}^{295,\mathrm{K}} = (3.64 \pm 0.92) \times 10^{-5}$. Upon cooling to 4 K, the loss tangents improved by approximately two orders of magnitude, reaching $\tanδ_{||}^{4,\mathrm{K}} = (1.56 \pm 0.52) \times 10^{-7}$ and $\tanδ_{\perp}^{4,\mathrm{K}} = (2.05 \pm 0.79) \times 10^{-7}$. These cryogenic values are higher than those reported in prior studies, likely due to a magnetic loss channel associated with an unidentified paramagnetic spin ensemble. These findings have implications for the use of CaWO$_4$ in applications such as spin-based quantum systems and cryogenic bolometry, highlighting the potential of WGMs for novel sensing applications.
Rxiv mechanobio

📰 "Onset of Driven Collisionless Reconnection in Strongly Magnetized Pair Plasmas"
arxiv.org/abs/2506.06059 #Physics.Plasm-Ph #Hep-Th #Force #Cell

arXiv.orgOnset of Driven Collisionless Reconnection in Strongly Magnetized Pair PlasmasWe investigate the onset of driven collisionless reconnection and plasmoid formation in a magnetically dominated pair plasma, using 2D particle-in-cell simulations. Two force-free flux tubes of radius $R$ are initially pushed together with a prescribed velocity, forming a current sheet whose width shrinks until reconnection sets in. % Even in our largest simulation with $R\approx 1600$ plasma skin depths, the sheet thickness at reconnection onset is comparable to the skin depth. Plasmoid chains are seen to develop when the sheet aspect ratio $A\gtrsim30$. In the strongly magnetized limit, the onset of reconnection occurs in roughly $2$ to $6$ light-crossing times $R/c$, depending on the imposed driving timescale, which controls the duration of the linear tearing phase. In the subsequent nonlinear merging phase, the evolution becomes effectively independent of the initially imposed velocity, leading to magnetic energy dissipation consistent with a normalized reconnection rate $\sim 0.1$. Our results have important implications for explosive release of magnetic energy in magnetospheres of compact objects and their surroundings.
Rxiv mechanobio

📰 "Testing strong-field QED with the avalanche precursor"
arxiv.org/abs/2506.02832 #Physics.Plasm-Ph #Dynamics #Hep-Ph #Cell

arXiv.orgTesting strong-field QED with the avalanche precursorA two-beam high-power laser facility is essential for the study of one of the most captivating phenomena predicted by strong-field quantum electrodynamics (QED) and yet unobserved experimentally: the avalanche-type cascade. In such a cascade, the energy of intense laser light can be efficiently transformed into high-energy radiation and electron-positron pairs. The future 50-petawatt-scale laser facility NSF OPAL will provide unique opportunities for studying such strong-field QED effects, as it is designed to deliver two ultra-intense, tightly focused laser pulses onto the interaction point. In this work, we investigate the potential of such a facility for studying elementary particle and plasma dynamics deeply in the quantum radiation-dominated regime, and the generation of QED avalanches. With 3D particle-in-cell simulations, we demonstrate that QED avalanche precursors can be reliably triggered under realistic laser parameters and layout (namely, focusing $f/2$, tilted optical axes, and non-ideal co-pointing) with the anticipated capabilities of NSF OPAL. We demonstrate that seed electrons can be efficiently injected into the laser focus by using targets of three types: a gas of heavy atoms, an overcritical plasma, and a thin foil. A strong positron and high-energy photon signal is generated in all cases. The cascade properties can be identified from the final particle distributions, which have a clear directional pattern. At increasing laser field intensity, such distributions provide signatures of the transition, first, to the radiation-dominated interaction regime, and then to a QED avalanche. Our findings can also be used for designing related future experiments.
💧🌏 Greg Cocks

Water Data Keep Us Strong | USGS WaterAlert Water Safety at Your Fingertips [USGS Water]
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usgs.gov/media/images/water-da and usgs.gov/media/images/usgs-wat <-- shared pair of USGS water-related infographics
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accounts.waterdata.usgs.gov/wa <-- shared link to subscribe to USGS Water Alert
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#water #hydrology #fedservice #fedscience #watersecurity #infographics #infographic #opendata #data #GIS #spatial #mapping #US #USA #alert #risk #hazard #monitoring #notification #waterdata #usecase #farms #agriculture #businesses #industry #residential #cost #economics #vitalresource #damage #assesr #resource #energy #HEP #watersupply #waterresources #management #planning #education #awareness #national #nation #WaterAlert #alerts #flows #streamflow #river #streamgauge #notification
@USGS

CEDAR

🚀 CONTUR 3 is here!

CONTUR uses RIVET and its huge library of LHC measurements to test new physics models via fast limit-setting and consistency checks.

The new release brings:
✔️ Improved stats treatments
✔️ Efficiency boosts
✔️ New plotting utilities & SM predictions
✔️ Many more measurements

Read more: arxiv.org/abs/2505.09272

arXiv.orgConstraints On New Theories Using Rivet : CONTUR version 3 release noteThe CONTUR toolkit exploits RIVET and its library of more than a thousand energy-frontier differential cross-section measurements from the Large Hadron Collider to allow rapid limit-setting and consistency checks for new physics models. In this note we summarise the main changes in the new CONTUR 3 major release series. These include additional statistical treatments, efficiency improvements, new plotting utilities and many new measurements and Standard Model predictions.
#HEP#ParticlePhysics#MonteCarlo
💧🌏 Greg Cocks

US National Inventory Of Dams [NID] [open spatial data]
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H/T Data Is Plural data-is-plural.com/
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“The National Inventory of Dams [nid.sec.usace.army.mil/] [is a is a congressionally authorized] ‘document[ing] all known dams in the U.S. and its territories that meet certain criteria’ related [nid.sec.usace.army.mil/#/about] to the dam’s height, reservoir size, and likely impacts of its ‘failure or mis-operation.’..."
#GIS #spatial #mapping #fedscience #NationalInventoryofDams #NLDI #US #USA #dams #criteria #inventory #opendata #downloadable #risk #hazard #infrastructure #energy #HEP #waterresources #hydroelectric #webmap #USACE #operations #dataset #safety #inspection #uses
@USACE @FEMA @EPA

💧🌏 Greg Cocks

Identification Of Geothermal Anomalies From Landsat Derived Land Surface Temperature, Mount Meager Volcanic Complex, British Columbia, Canada
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doi.org/10.1016/j.rse.2025.114 <-- shared paper
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“Highlights:
• A novel method for detecting geothermal components from solar energy dominated LST.
• Using LST time series to eliminate temporal variant solar energy input.
• Uncertainty in anomaly identification quantified by probability measure.
• Capable of revealing LST anomalies caused by geothermal, anthropogenic and surface processes..."
#GIS #spatial #mapping #britishcolumbia #BC #solar #geothermal #remotesensing #earthobservation #LST #spatialanalysis #spatiotemporal #naturalresources #volcanic #geology #geostatistics #landsurfacetemperature #satellite #geothermalheatflux #GHF #energybalance #calculation #model #MountMeager #Landsat #landsat8 #hotspring #landslide #massmovement #engineeringgeology #spring #seep #anthropogenic #HEP #hydropower #monitoring #risk #hazard

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