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We advocate for a large scale imaging survey of nearby young moving groups and star-forming regions to directly detect exoplanets over an unexplored range of masses, ages and orbits. Discovered objects will be identified early enough in JWST's lifetime to leverage its unparalleled capabilities for long-term atmospheric characterisation, and will uniquely complement the known population of exoplanets and brown dwarfs. Furthermore, this survey will constrain the occurrence of the novel wide sub-Jovian exoplanet population, informing multiple theories of planetary formation and evolution. Observations with NIRCam F200W+F444W dual-band coronagraphy will readily provide sub-Jupiter mass sensitivities beyond ~0.4" (F444W) and can also be used to rule out some contaminating background sources (F200W). At this large scale, targets can be sequenced by spectral type to enable robust self-referencing for PSF subtraction. This eliminates the need for dedicated reference observations required by GO programs and dramatically increases the overall science observing efficiency. With an exposure of ~30 minutes per target, the sub-Jupiter regime can be explored across 250 targets for ~400 hours of exposure time including overheads. An additional, pre-allocated, ~100 hours of observing time would enable rapid multi-epoch vetting of the lowest mass detections (which are undetectable in F200W). The total time required for a survey such as this is not fixed, and could be scaled in conjunction with the minimum number of detected exoplanet companions., Comment: 5 pages, 2 figures. This white paper was submitted following a call from the "Working Group on Strategic Exoplanet Initiatives with HST and JWST" (https://sites.google.com/view/exoplanet-strategy-wg, final report in 10.48550/arXiv.2404.02932)

We advocate for further prioritisation of atmospheric characterisation observations of high mass transiting exoplanets and brown dwarfs. This population acts as a unique comparative sample to the directly imaged exoplanet and brown dwarf populations, of which a range of JWST characterisation observations are planned. In contrast, only two observations of transiting exoplanets in this mass regime were performed in Cycle 1, and none are planned for Cycle 2. Such observations will: improve our understanding of how irradiation influences high gravity atmospheres, provide insights towards planetary formation and evolution across this mass regime, and exploit JWST's unique potential to characterise exoplanets across the known population., Comment: 4 pages, 2 figures. This white paper was submitted following a call from the "Working Group on Strategic Exoplanet Initiatives with HST and JWST" (https://sites.google.com/view/exoplanet-strategy-wg, final report in 10.48550/arXiv.2404.02932)

We present a commentary on the famous 1964 paper of John Bell that rules out the entire class of underlying hidden variable theories for quantum mechanics that are local., Comment: Commentary, 4 pages, to appear in the November issue of Resonance

Equitable urban transportation applications require high-fidelity digital representations of the built environment: not just streets and sidewalks, but bike lanes, marked and unmarked crossings, curb ramps and cuts, obstructions, traffic signals, signage, street markings, potholes, and more. Direct inspections and manual annotations are prohibitively expensive at scale. Conventional machine learning methods require substantial annotated training data for adequate performance. In this paper, we consider vision language models as a mechanism for annotating diverse urban features from satellite images, reducing the dependence on human annotation to produce large training sets. While these models have achieved impressive results in describing common objects in images captured from a human perspective, their training sets are less likely to include strong signals for esoteric features in the built environment, and their performance in these settings is therefore unclear. We demonstrate proof-of-concept combining a state-of-the-art vision language model and variants of a prompting strategy that asks the model to consider segmented elements independently of the original image. Experiments on two urban features -- stop lines and raised tables -- show that while direct zero-shot prompting correctly annotates nearly zero images, the pre-segmentation strategies can annotate images with near 40% intersection-over-union accuracy. We describe how these results inform a new research agenda in automatic annotation of the built environment to improve equity, accessibility, and safety at broad scale and in diverse environments.

A crucial yet challenging task in galaxy evolution studies is the identification of distant merging galaxies, a task which suffers from a variety of issues ranging from telescope sensitivities and limitations to the inherently chaotic morphologies of young galaxies. In this paper, we use random forests and convolutional neural networks to identify high-redshift JWST CEERS galaxy mergers. We train these algorithms on simulated $3

High proved the following theorem. If the intersections of any two congruent copies of a plane convex body are centrally symmetric, then this body is a circle. In our paper we extend the theorem of High to the sphere and the hyperbolic plane, and partly to spaces of constant curvature. We also investigate the dual question about the convex hull of the unions, rather than the intersections. Let us have in $H^2$ proper closed convex subsets $K,L$ with interior points, such that the numbers of the connected components of the boundaries of $K$ and $L$ are finite. We exactly describe all pairs of such subsets $K,L$, whose any congruent copies have an intersection with axial symmetry; there are nine cases. (The cases of $S^2$ and ${\Bbb{R}}^2$ were described in Part I, i.e., \cite{5}.) Let us have in $S^d$, ${\Bbb{R}}^d$ or $H^d$ proper closed convex $C^2_+$ subsets $K,L$ with interior points, such that all sufficiently small intersections of their congruent copies are symmetric w.r.t.\ a particular hyperplane. Then the boundary components of both $K$ and $L$ are congruent, and each of them is a sphere, a parasphere or a hypersphere. Let us have a pair of convex bodies in $S^d$, ${\Bbb{R}}^d$ or $H^d$, which have at any boundary points supporting spheres (for $S^d$ of radius less than $\pi /2$). If the convex hull of the union of any congruent copies of these bodies is centrally symmetric, then our bodies are congruent balls (for $S^d$ of radius less than $\pi /2$). An analogous statement holds for symmetry w.r.t.\ a particular hyperplane. For $d=2$, suppose the existence of the above supporting circles (for $S^2$ of radius less than $\pi /2$), and, for $S^2$, smoothness of $K$ and $L$. If we suppose axial symmetry of all the above convex hulls, then our bodies are (incongruent) circles (for $S^2$ of radii less than $\pi /2$)., Comment: 48 pages. arXiv admin note: text overlap with arXiv:1601.04494

In a recent review of a paper by the Yakutsk Group, submitted to the Journal Physics of Atomic Nuclei and arXiv, the energy scales of the Yakutsk and Telescope Array (TA) experiments were examined. The authors developed a custom detector response simulator incorporating ionization, bremsstrahlung, pair production, and Compton scattering. Applying this simulator to both Yakutsk and TA surface detectors, they concluded that the TA energy scale might be incorrect due to a misdefined ``response unit.'' They referenced the TA's ``energy deposit formula'' from the literature, scaling it by two factors attributed to the thickness and density of the TA scintillator. Their simulations, using the QGSJET-II-04 hadronic interaction model, agreed with TA's calculations for vertical showers but not for inclined showers, suggesting an incorrect VEM unit of 2.05 MeV. However, this conclusion was found to be incorrect. The TA's energy deposit formula, derived from detailed Monte Carlo simulations using GEANT4, accurately represents the most probable energy deposit by a charged particle in the TA scintillator. The value of 2.05 MeV accounts for the scintillator's thickness and density and is validated by excellent agreement between TA's simulated and observed data. The Yakutsk Group's misinterpretation and incorrect application of the TA formula led to their erroneous conclusion., Comment: 2pages, comments on arXiv:2404.16948

This white paper summarizes the Workshop on Polarized Target Studies with Real Photons in Hall D at Jefferson Lab, that took place on 21 February 2024. The Workshop included about 45 participants both online and in person at Florida State University in Tallahassee. Contributions describe the experimental infrastructure available in Hall D and potential physics applications. The rate and detection capabilities of Hall D are outlined, as well as the properties of a circularly polarized photon beam and a polarized target. Possible physics measurements include light and strange quark baryon spectroscopy, the GDH sum rule, proton structure accessed through measurement of Generalized Parton Distributions and modification of nucleon structure within the nuclear medium., Comment: 25 pages, 8 figures