Search

We present JWST/NIRSpec PRISM follow-up of candidate galaxies at z=9-11 selected from deep JWST/NIRCam photometry in GLASS-JWST Early Release Science data. We spectroscopically confirm six sources with secure redshifts at z = 9.52-10.43, each showing multiple emission lines. An additional object is likely at z = 10.66, based on its Lya-break and a single emission feature, while one source is a lower redshift interloper. The sample includes the first JWST-detected candidate at z=10, GHZ1/GLASS-z10, which we confirm at z = 9.875, and the X-ray detected AGN GHZ9 confirmed at z = 10.145. Three objects in our sample, including GHZ9, have EW(CIII])>20A and occupy a region compatible with AGN emission in the EW(CIII]) vs CIV/CIII] diagram. The spectroscopic sample confirms a high abundance of galaxies at z > 9. We measure a number density of z=10 galaxies in the GLASS-JWST ERS field that is a factor of >3 higher than other JWST-based estimates at demagnified rest-frame magnitudes of -21 < Muv < -19. We find that the positions of these galaxies in redshift and angular space are not consistent with all of them being part of a unique progenitor of present-day galaxy clusters. The high density of objects in the GLASS region can be explained either by clustering on large scales or by a superposition of different forming structures of which we observe only the brightest members. By considering all the spectroscopic z=10 sources in the Abell-2744 field, we identify two potential galaxy proto-clusters centered around GHZ9 and JD1, with relative separations between their members of 1-2 pMpc. The potential AGN nature of three of the sources in our sample lends support to a scenario in which the high abundance of bright sources determined by JWST surveys at cosmic dawn may be affected by AGN contribution to their UV luminosity., Comment: Submitted to A&A

We present the first spectroscopic confirmation of a dust-obscured dwarf galaxy, CEERS-14821. The analysis is performed combining JWST NIRCam broad-band photometry and NIRSpec/PRISM spectroscopic data. From the detection of multiple rest-frame optical lines, we derive that CEERS-14821 is located at $z=4.883\pm0.003$. Moreover, from a secure detection of the $H_{\alpha}$ and $H_{\beta}$ we derived that the galaxy has a dust extinction ranging from Av=2.2 to Av=3.3, depending on the assumed reddening law. This value is extremely large given that we estimated a low stellar mass around log(M/Mo)=8.0-8.2. Moreover, using different metallicity tracers, we verify that the galaxy is also metal-rich, with 12+log(O/H)>8.3. This is well above the expectation from both the mass-metallicity relation and the fundamental mass-metalliticy relation. CEERS-14821 is going through a burst of star formation, there are no indications of a strong contribution from an active galactic nuclei (f(AGN)<0.5 with respect to the total dust luminosity). Based on the rest-frame optical images, this source has a size compatible with galaxies of similar stellar mass and redshift. Finally, with the current data, it seems that there are galaxies closely interacting with CEERS-14821., Comment: 14 pages, 11 figures. Submitted to A&A

JWST observations of the young Galactic supernova remnant Cassiopeia A revealed an unexpected structure seen as a green emission feature in colored composite MIRI F1130W and F1280W images - hence dubbed the Green Monster - that stretches across the central parts of the remnant in projection. Combining the kinematic information from NIRSpec and MIRI MRS with the multi-wavelength imaging from NIRCam and MIRI, we associate the Green Monster with circumstellar material that was lost during an asymmetric mass-loss phase. MIRI images are dominated by dust emission but its spectra show emission lines from Ne, H and Fe with low radial velocities indicative of a CSM nature. An X-ray analysis of this feature in a companion paper (Vink et al. 2024) supports its CSM nature and detects significant blue shifting, thereby placing the Green Monster on the near side, in front of the Cas A SN remnant. The most striking features of the Green Monster are dozens of almost perfectly circular 1" - 3" sized holes, most likely created by interaction between high-velocity SN ejecta material and the CSM. Further investigation is needed to understand whether these holes were formed by small 8000-10500 km/s N-rich ejecta knots that penetrated and advanced out ahead of the remnant's 5000 - 6000 km/s outer blastwave, or by narrow ejecta fingers that protrude into the forward-shocked CSM. The detection of the Green Monster provides further evidence of the highly asymmetric mass-loss that Cas A's progenitor star underwent prior to explosion., Comment: 28 pages, 12 figures, resubmitted to ApJL after minor revision, comments welcome

To build an economically viable stellarator, it is essential to find a configuration that satisfies a set of favorable properties to achieve efficient steady-state nuclear fusion. One such property is omnigenity, which ensures confinement of trapped particles. After creating an omnigenous equilibrium, one must also ensure reduced transport resulting from kinetic and magnetohydrodynamic (MHD) instabilities. This study introduces and leverages the GPU-accelerated DESC optimization suite, which is used to design stable high-$\beta$ omnigenous equilibria, achieving Mercier, ideal ballooning, and enhanced kinetic ballooning stability. We explain the link between ideal and kinetic ballooning modes and discover stellarators with second stability, a regime of large pressure gradient where an equilibria becomes ideal ballooning stable., Comment: Supplementary material appended after the appendix. 33 pages + 10 pages supplementary material, 13 figures, 4 tables

Detectors at future high energy colliders will face enormous technical challenges. Disentangling the unprecedented numbers of particles expected in each event will require highly granular silicon pixel detectors with billions of readout channels. With event rates as high as 40 MHz, these detectors will generate petabytes of data per second. To enable discovery within strict bandwidth and latency constraints, future trackers must be capable of fast, power efficient, and radiation hard data-reduction at the source. We are developing a radiation hard readout integrated circuit (ROIC) in 28nm CMOS with on-chip machine learning (ML) for future intelligent pixel detectors. We will show track parameter predictions using a neural network within a single layer of silicon and hardware tests on the first tape-outs produced with TSMC. Preliminary results indicate that reading out featurized clusters from particles above a modest momentum threshold could enable using pixel information at 40 MHz., Comment: Contribution to the 42nd International Conference on High Energy Physics (ICHEP)

Mixed membership models are a flexible class of probabilistic data representations used for unsupervised and semi-supervised learning, allowing each observation to partially belong to multiple clusters or features. In this manuscript, we extend the framework of functional mixed membership models to allow for covariate-dependent adjustments. The proposed model utilizes a multivariate Karhunen-Lo\`eve decomposition, which allows for a scalable and flexible model. Within this framework, we establish a set of sufficient conditions ensuring the identifiability of the mean, covariance, and allocation structure up to a permutation of the labels. This manuscript is primarily motivated by studies on functional brain imaging through electroencephalography (EEG) of children with autism spectrum disorder (ASD). Specifically, we are interested in characterizing the heterogeneity of alpha oscillations for typically developing (TD) children and children with ASD. Since alpha oscillations are known to change as children develop, we aim to characterize the heterogeneity of alpha oscillations conditionally on the age of the child. Using the proposed framework, we were able to gain novel information on the developmental trajectories of alpha oscillations for children with ASD and how the developmental trajectories differ between TD children and children with ASD., Comment: 71 pages including supplement

We revisit the Unruh effect with a direct, probability-level calculation. We rederive the transition rate of a uniformly accelerating Unruh-DeWitt monopole detector coupled to a massive scalar field, from both the perspective of an inertial (Minkowski) observer and an accelerating (Rindler) observer. We show that, for a measurement at a finite time after the initial state is prepared, the two perspectives give the same transition rate. We show that an inertial detector in a thermal bath of Minkowski particles responds differently to the accelerated detector (which perceives a thermal bath of Rindler particles), except in the case of a massless field where there is agreement at all times. Finally, numerical results for the transition rate are presented and explained. We highlight the transient effects caused by forcing the field to initially be in the Minkowski vacuum state., Comment: 23 pages, 3 figures

Electromagnetic microtearing modes (MTMs) have been observed in many different spherical tokamak regimes. Understanding how these and other electromagnetic modes nonlinearly saturate is likely critical in understanding the confinement of a high $\beta$ spherical tokamak (ST). Equilibrium $E\times B$ sheared flows have sometimes been found to significantly suppress low $\beta$ ion scale transport in both gyrokinetic simulations and in experiment. This work aims to understand the conditions under which $E\times B$ sheared flow impacts on the saturation of MTM simulations. Two experimental regimes are examined from MAST and NSTX, on surfaces that have unstable MTMs. The MTM driven transport on a local flux surface in MAST is shown to be more resilient to suppression via $E\times B$ shear, compared to the case from NSTX where the MTM transport is found to be significantly suppressed. This difference in the response to flow shear is explained through the impact of magnetic shear, $\hat{s}$ on the MTM linear growth rate dependence on ballooning angle, $\theta_0$. At low $\hat{s}$, the growth rate depends weakly on $\theta_0$, but at higher $\hat{s}$, the MTM growth rate peaks at $\theta_0 = 0$, with regions of stability at higher $\theta_0$. Equilibrium $E\times B$ sheared flows act to advect the $\theta_0$ of a mode in time, providing a mechanism which suppresses the transport from these modes when they become stable. The dependence of $\gamma^{MTM}$ on $\theta_0$ is in qualitative agreement with a recent theory [M.R. Hardman et al (2023)] at low $\beta$ when $q\sim1$, but the agreement worsens at higher $q$ where the theory breaks down. This work highlights the important role of the safety factor profile in determining the impact of equilibrium $E\times B$ shear on the saturation level of MTM turbulence., Comment: 20 pages, 16 figures

We present a sample of 50 H-alpha detected broad-line active galactic nuclei (BLAGN) at redshifts 3.50), independent of the contributions of emission lines to the broadband photometry. We construct the black hole (BH) mass function at 3.5

We analyze $\textit{JWST}$ CEERS NIRCam images to present {the first estimate} of the observed fraction and properties of bars out to $z \sim 4$. We analyze a sample of 1770 galaxies with stellar mass $M_\star > 10^{10} M_\odot$ at $0.5 \leq z \leq 4$ and identify barred galaxies via ellipse fits and visual classification of both F200W and F444W images. Our results apply mainly to bars with projected semi-major axis $a_{\rm bar}$ $> 1.5 $ kpc ($\sim$ 2 $\times$ PSF in F200W images) that can be robustly traced by ellipse fits. For such bars, the {observed} bar fraction at $z\sim$ 2-4 is low ($\lesssim 10\%$), and they appear to be emerging at least as early as $z\sim 4$ when the Universe was $\sim$ 13\% of its present age. At $z\sim$ 2-4, compared to our results, TNG50 simulations {predict} a significantly larger bar fraction due to a large population of small bars with $a_{\rm bar}$ $< 1.5$ kpc {that we cannot robustly detect}. If such a population exists, the true bar fraction may be significantly higher than our results. At $z \ge 1.5$, many barred galaxies show nearby neighbors, suggesting bars may be tidally triggered. {From $z \sim 4$ to $z \sim 0.5$, the observed bar fraction, average projected bar length, and projected bar strength rise.} Our results highlight the early emergence and evolution of barred galaxies and the rising importance of bar-driven secular evolution from $z \sim$4 to today., Comment: 25 pages, 16 figures, submitted to ApJ, Comments are welcome

We present a set of photometric catalogs primarily aimed at providing the community with a comprehensive database for the study of galaxy populations in the high redshift Universe. The set gathers data from eight JWST NIRCam observational programs, targeting the Abell 2744 (GLASS-JWST, UNCOVER, DDT2756 and GO3990), EGS (CEERS), COSMOS and UDS (PRIMER), and GOODS North and South (JADES and NGDEEP) deep fields, for a total area of $\sim$0.2 sq. degrees. Photometric estimates are obtained by means of well-established techniques, including tailored improvements designed to enhance the performance on the specific dataset. We also include new measurements from HST archival data, thus collecting 16 bands spanning from 0.44 to 4.44 $\mu$m. A grand total of $\sim$530 thousand sources is detected on stacks of NIRCam 3.56 and 4.44 $\mu$m mosaics. We assess the photometric accuracy by comparing fluxes and colors against archival catalogs. We also provide photometric redshift estimates, statistically validated against a large set of robust spectroscopic data. The catalogs are publicly available on the Astrodeep website., Comment: 28 pages, 16 figures; accepted for publication on Astronomy & Astrophysics

In 2017, the next generation Very Large Array (ngVLA) Science Advisory Council, together with the international astronomy community, developed a set of five Key Science Goals (KSGs) to inform, prioritize and refine the technical capabilities of a future radio telescope array for high angular resolution operation from 1.2 - 116 GHz with 10 times the sensitivity of the Jansky VLA and ALMA. The resulting KSGs, which require observations at centimeter and millimeter wavelengths that cannot be achieved by any other facility, represent a small subset of the broad range of astrophysical problems that the ngVLA will be able address. This document presents an update to the original ngVLA KSGs, taking account of new results and progress in the 7+ years since their initial presentation, again drawing on the expertise of the ngVLA Science Advisory Council and the broader community in the ngVLA Science Working Groups. As the design of the ngVLA has also matured substantially in this period, this document also briefly addresses initial expectations for ngVLA data products and processing that will be needed to achieve the KSGs. The original ngVLA KSGs endure as outstanding problems of high priority. In brief, they are: (1) Unveiling the Formation of Solar System Analogues; (2) Probing the Initial Conditions for Planetary Systems and Life with Astrochemistry; (3) Charting the Assembly, Structure, and Evolution of Galaxies from the First Billion Years to the Present; (4) Science at the Extremes: Pulsars as Laboratories for Fundamental Physics; (5) Understanding the Formation and Evolution of Stellar and Supermassive Black Holes in the Era of Multi-Messenger Astronomy., Comment: 29 pages, 9 figures, ngVLA memo 125. arXiv admin note: text overlap with arXiv:1711.09960

The LPC EFT workshop was held April 25-26, 2024 at the University of Notre Dame. The workshop was organized into five thematic sessions: "how far beyond linear" discusses issues of truncation and validity in interpretation of results with an eye towards practicality; "reconstruction-level results" visits the question of how best to design analyses directly targeting inference of EFT parameters; "logistics of combining likelihoods" addresses the challenges of bringing a diverse array of measurements into a cohesive whole; "unfolded results" tackles the question of designing fiducial measurements for later use in EFT interpretations, and the benefits and limitations of unfolding; and "building a sample library" addresses how best to generate simulation samples for use in data analysis. This document serves as a summary of presentations, subsequent discussions, and actionable items identified over the course of the workshop.

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

We present a detailed JWST/NIRSpec and NIRCam analysis of a gravitationally-lensed galaxy ($\rm \mu=17-21$) at redshift 6.14 magnified by the Hubble Frontier Field galaxy cluster MACS J0416. The target galaxy is overall a typical compact and UV-faint ($\rm M_{UV}=-17.8$) Lyman-$\alpha$ emitter; yet, the large magnification allows the detailed characterisation of structures on sub-galactic (down to few parsec) scales. Prominent optical $\rm H\alpha$, $\rm H\beta$ and [OIII]$\lambda\lambda4959,5007$ lines are spatially resolved with the high spectral resolution grating (G395H, R~2700), with large equivalent widths, EW($\rm H\beta$+[OIII])$\gtrsim1000$ \AA, and elevated ionising photon production efficiencies $\rm log(\xi_{ion}/erg^{-1}Hz)=25.2-25.7$. NIRCam deep imaging reveals the presence of compact rest-UV bright regions along with individual star clusters of sizes $\rm R_{eff}=3-8~pc$ and masses $\rm M\sim2\cdot10^5-5\cdot10^{6}~M_\odot$ These clusters are characterised by steep UV slopes, $\rm\beta_{UV}\lesssim-2.5$, in some cases associated with a dearth of line emission, indicating possible leaking of the ionising radiation, as also supported by a Lyman-$\rm \alpha$ emission peaking at $\rm \sim100~km~s^{-1}$ from the systemic redshift. While the entire system is characterised by low-metallicity, $\sim0.1~Z_\odot$, the NIRSpec-IFU map also reveals the presence of a low-luminosity, metal-poor region with $\rm Z\lesssim2\%~Z_\odot$, barely detected in NIRCam imaging; this region is displaced by $\rm >200~pc$ from one of the UV brightest structures of the system, and it would have been too faint to detect if not for the large magnification of the system., Comment: 19 pages (11 figures, 2 tables) + appendix (3 pages, 4 figures, 1 table). Submitted to A&A; comments are welcome

We report the serendipitous discovery of a faint (M_UV > -12.2), low-metallicity (Z ~ 0.02 Zsun), ionizing source (dubbed T2c) with a spectroscopic redshift of z=6.146. T2c is part of a larger structure amplified by the Hubble Frontier Field galaxy cluster MACSJ0416, and was observed with JWST/NIRSpec IFU. Stacking the short-wavelength NIRCam data reveals no stellar continuum detection down to a magnitude limit of m_UV ~ 31.0 (3 sigma). However, prominent Hb, [OIII]4959,5007, and Ha emissions are detected, with equivalent widths exceeding 200A, 800A, and 1300A (3 sigma), respectively. The corresponding intrinsic (magnification-corrected x23 +/- 3) ultraviolet and optical rest-frame magnitudes exceed 34.4 and 33.9 (corresponding to M_uv and M_opt fainter than -12.2 and -12.8, at lambda_rest ~ 2000A and ~5000A, respectively), suggesting a stellar mass lower than a few 10^4 Msun under an instantaneous burst scenario. The inferred ionizing photon production efficiency (xi_ion) is high, xi_ion >~ 26.08(25.86) 3(5)sigma, assuming no dust attenuation and no Lyman continuum leakage, indicating the presence of massive stars despite the low mass of the object. The very poor sampling of the initial mass function at such low mass star-forming complex suggests that the formation of very massive stars might be favored in very low metallicity environments. T2c is surrounded by Balmer and weak oxygen emission on a spatial scale of a few hundred parsecs after correcting for lensing effects. This system resembles an HII region potentially powered by currently undetected, extremely efficient, low-metallicity star complexes or clusters. We propose that massive O-type stars populate this low-mass and metallicity high-redshift satellites, likely caught in an early and short formation phase, contributing to the ionization of the surrounding medium., Comment: 9 pages, 5 figures, 1 table. Submitted to A&A. Comments are welcome

We present a smart pixel prototype readout integrated circuit (ROIC) designed in CMOS 28 nm bulk process, with in-pixel implementation of an artificial intelligence (AI) / machine learning (ML) based data filtering algorithm designed as proof-of-principle for a Phase III upgrade at the Large Hadron Collider (LHC) pixel detector. The first version of the ROIC consists of two matrices of 256 smart pixels, each 25$\times$25 $\mu$m$^2$ in size. Each pixel consists of a charge-sensitive preamplifier with leakage current compensation and three auto-zero comparators for a 2-bit flash-type ADC. The frontend is capable of synchronously digitizing the sensor charge within 25 ns. Measurement results show an equivalent noise charge (ENC) of $\sim$30e$^-$ and a total dispersion of $\sim$100e$^-$ The second version of the ROIC uses a fully connected two-layer neural network (NN) to process information from a cluster of 256 pixels to determine if the pattern corresponds to highly desirable high-momentum particle tracks for selection and readout. The digital NN is embedded in-between analog signal processing regions of the 256 pixels without increasing the pixel size and is implemented as fully combinatorial digital logic to minimize power consumption and eliminate clock distribution, and is active only in the presence of an input signal. The total power consumption of the neural network is $\sim$ 300 $\mu$W. The NN performs momentum classification based on the generated cluster patterns and even with a modest momentum threshold, it is capable of 54.4\% - 75.4\% total data rejection, opening the possibility of using the pixel information at 40MHz for the trigger. The total power consumption of analog and digital functions per pixel is $\sim$ 6 $\mu$W per pixel, which corresponds to $\sim$ 1 W/cm$^2$ staying within the experimental constraints., Comment: IEEE NSS MIC RSTD 2024

This note gives an overview of the tools for predicting expectations in the Standard Model effective field theory (SMEFT) at the tree level and one loop available through event generators. Methods of event reweighting, the separate simulation of squared matrix elements, and the simulation of the full SMEFT process are compared in terms of statistical efficacy and potential biases., Comment: 40 pages, 23 figures. Authorlist fixed

We present the first high-resolution, high-frequency radio continuum survey that fully maps an extragalactic deep field: the 10GHz survey of the Great Observatories Origins Deep Survey-North (GOODS-N) field. This is a Large Program of the Karl G. Jansky Very Large Array that allocated 380 hours of observations using the X-band ($8-12$GHz) receivers, leading to a 10GHz mosaic of the GOODS-field with an average rms noise $\sigma_{\rm n}=671\,\rm nJy\,beam^{-1}$ and angular resolution $\theta_{1/2}=0.22$arcsec across 297$\rm arcmin^2$. To maximize the brightness sensitivity we also produce a low-resolution mosaic with $\theta_{1/2}=1.0$arcsec and $\sigma_{\rm n}=968\,\rm nJy\,beam^{-1}$, from which we derive our master catalog containing 256 radio sources detected with peak signal-to-noise ratio $\geq 5$. Radio source size and flux density estimates from the high-resolution mosaic are provided in the master catalog as well. The total fraction of spurious sources in the catalog is 0.75%. Monte Carlo simulations are performed to derive completeness corrections of the catalog. We find that the 10GHz radio source counts in the GOODS-N field agree, in general, with predictions from numerical simulations/models and expectations from 1.4 and 3GHz radio counts., Comment: Accepted for publication in ApJ

LiteBIRD, the next-generation cosmic microwave background (CMB) experiment, aims for a launch in Japan's fiscal year 2032, marking a major advancement in the exploration of primordial cosmology and fundamental physics. Orbiting the Sun-Earth Lagrangian point L2, this JAXA-led strategic L-class mission will conduct a comprehensive mapping of the CMB polarization across the entire sky. During its 3-year mission, LiteBIRD will employ three telescopes within 15 unique frequency bands (ranging from 34 through 448 GHz), targeting a sensitivity of 2.2\,$\mu$K-arcmin and a resolution of 0.5$^\circ$ at 100\,GHz. Its primary goal is to measure the tensor-to-scalar ratio $r$ with an uncertainty $\delta r = 0.001$, including systematic errors and margin. If $r \geq 0.01$, LiteBIRD expects to achieve a $>5\sigma$ detection in the $\ell=$2-10 and $\ell=$11-200 ranges separately, providing crucial insight into the early Universe. We describe LiteBIRD's scientific objectives, the application of systems engineering to mission requirements, the anticipated scientific impact, and the operations and scanning strategies vital to minimizing systematic effects. We will also highlight LiteBIRD's synergies with concurrent CMB projects., Comment: 23 pages, 9 figures, 1 table, SPIE Astronomical Telescopes + Instrumentation 2024

Anomalous Microwave Emission (AME) is a major component of Galactic emission in the frequency band 10 to 60 GHz and is commonly modelled as rapidly rotating spinning dust grains. The photodissociation region (PDR) at the boundary of the $\lambda$-Orionis Hii region has been identified by several recent analyses as one of the brightest spinning dust emitting sources in the sky. We investigate the Barnard 30 dark cloud, a dark cloud embedded within the $\lambda$-Orionis PDR. We use total-power observations of Barnard 30 from the CO Mapping Array Project (COMAP) pathfinder instrument at 26 to 34GHz with a resolution of 4.5 arcminutes alongside existing data from Planck, WISE, IRAS, ACT, and the 1.447GHz GALFACTS survey. We use aperture photometry and template fitting to measure the spectral energy distribution of Barnard 30. We find that the spinning dust is the dominant emission component in the 26 to 34GHz range at the $7 \sigma$ level ($S_{30GHz} = 2.85\pm0.43$Jy). We find no evidence that polycyclic aromatic hydrocarbons are the preferred carrier for the spinning dust emission, suggesting that the spinning dust carriers are due to a mixed population of very small grains. Finally, we find evidence for variations in spinning dust emissivity and peak frequency within Barnard 30, and that these variations are possibly driven by changes in dust grain population and the total radiation field. Confirming the origin of the variations in the spinning dust spectrum will require both future COMAP observations at 15GHz combined with spectroscopic mid-infrared data of Barnard 30., Comment: 21 pages, 13 figures. Submitted to MNRAS

Major European Union-funded research infrastructure and open science projects have traditionally included dissemination work, for mostly one-way communication of the research activities. Here we present and review our radical re-envisioning of this work, by directly engaging citizen science volunteers into the research. We summarise the citizen science in the Horizon-funded projects ASTERICS (Astronomy ESFRI and Research Infrastructure Clusters) and ESCAPE (European Science Cluster of Astronomy and Particle Physics ESFRI Research Infrastructures), engaging hundreds of thousands of volunteers in providing millions of data mining classifications. Not only does this have enormously more scientific and societal impact than conventional dissemination, but it facilitates the direct research involvement of what is often arguably the most neglected stakeholder group in Horizon projects, the science-inclined public. We conclude with recommendations and opportunities for deploying crowdsourced data mining in the physical sciences, noting that the primary goal is always the fundamental research question; if public engagement is the primary goal to optimise, then other, more targeted approaches may be more effective., Comment: Accepted by European Physical Journal Plus. Invited review. 26 pages, 1 figure

We present UV/optical/NIR observations and modeling of supernova (SN) 2024ggi, a type II supernova (SN II) located in NGC 3621 at 7.2 Mpc. Early-time ("flash") spectroscopy of SN 2024ggi within +0.8 days of discovery shows emission lines of H I, He I, C III, and N III with a narrow core and broad, symmetric wings (i.e., IIn-like) arising from the photoionized, optically-thick, unshocked circumstellar material (CSM) that surrounded the progenitor star at shock breakout. By the next spectral epoch at +1.5 days, SN 2024ggi showed a rise in ionization as emission lines of He II, C IV, N IV/V and O V became visible. This phenomenon is temporally consistent with a blueward shift in the UV/optical colors, both likely the result of shock breakout in an extended, dense CSM. The IIn-like features in SN 2024ggi persist on a timescale of $t_{\rm IIn} = 3.8 \pm 1.6$ days at which time a reduction in CSM density allows the detection of Doppler broadened features from the fastest SN material. SN 2024ggi has peak UV/optical absolute magnitudes of $M_{\rm w2} = -18.7$ mag and $M_{\rm g} = -18.1$ mag that are consistent with the known population of CSM-interacting SNe II. Comparison of SN 2024ggi with a grid of radiation hydrodynamics and non-local thermodynamic equilibrium (nLTE) radiative-transfer simulations suggests a progenitor mass-loss rate of $\dot{M} = 10^{-2}$M$_{\odot}$ yr$^{-1}$ ($v_w$ = 50 km/s), confined to a distance of $r < 5\times 10^{14}$ cm. Assuming a wind velocity of $v_w$ = 50 km/s, the progenitor star underwent an enhanced mass-loss episode in the last ~3 years before explosion., Comment: Accepted for publication in ApJ. arXiv admin note: text overlap with arXiv:2306.04721, arXiv:2403.02382

A quasi-linear reduced transport model is developed from a database of high-$\beta$ electromagnetic nonlinear gyrokinetic simulations performed with Spherical Tokamak for Energy Production (STEP) relevant parameters. The quasi-linear model is fully electromagnetic and accounts for the effect of equilibrium flow shear using a novel approach. Its flux predictions are shown to agree quantitatively with predictions from local nonlinear gyrokinetic simulations across a broad range of STEP-relevant local equilibria. This reduced transport model is implemented in the T3D transport solver that is used to perform the first flux-driven simulations for STEP to account for transport from hybrid-KBM turbulence, which dominates over a wide region of the core plasma. Nonlinear gyrokinetic simulations of the final transport steady state from T3D return turbulent fluxes that are consistent with the reduced model, indicating that the quasi-linear model may also be appropriate for describing the transport steady state. Within the assumption considered here, our simulations support the existence of a transport steady state in STEP with a fusion power comparable to that in the burning flat-top of the conceptual design, but do not demonstrate how this state can be accessed.

This paper presents an overview of the high-redshift extragalactic science case for the Single Aperture Large Telescope for Universe Studies (SALTUS) far-infrared NASA probe-class mission concept. Enabled by its 14m primary reflector, SALTUS offers enormous gains in spatial resolution and spectral sensitivity over previous far-IR missions. SALTUS would be a versatile observatory capable of responding to the scientific needs of the extragalactic community in the 2030s, and a natural follow-on to the near- and mid-IR capabilities of JWST. Key early-universe science goals for SALTUS focus on understanding the role of galactic feedback processes in regulating galaxy growth across cosmic time, and charting the rise of metals and dust from the early universe to the present. This paper summarizes these science cases and the performance metrics most relevant for high-redshift observations., Comment: Submitted to JATIS as part of a special issue on SALTUS. Key performance metrics in Figs. 1 and 2

Mariah is an augmented reality (AR) mobile application that exposes power structures (e.g., capitalism, patriarchy, white supremacy) through storytelling and celebrates acts of resistance against them. People can use Mariah to "legally trespass" the metaverse as a form of protest. Mariah provides historical context to the user's physical surroundings by superimposing images and playing stories about people who have experienced, and resisted, injustice. We share two implementations of Mariah that raise questions about free speech and property rights in the metaverse: (1) a protest against museums accepting "dirty money" from the opioid epidemic; and (2) a commemoration of sites where people have resisted power structures. Mariah is a case study for how experimenting with a technology in non-sanctioned ways (i.e., "hacking") can expose ways that it might interact with, and potentially amplify, existing power structures., Comment: Presented at CHI 2024 (arXiv:2404.05889)

The ultraviolet continuum traces young stars while the near-infrared unveils older stellar populations and dust-obscured regions. Balmer emission lines provide insights on gas properties and young stellar objects but are highly affected by dust attenuation. The near-infrared Paschen lines suffer less dust attenuation and can be used to measure star formation rates (SFRs) in star-forming regions obscured by dust clouds. We select 13 sources between redshifts 1 and 3 observed with HST, JWST/NIRCam and NIRSpec based on the availability of at least one Balmer and one Paschen line with S/N > 5. With a newly-developed version of CIGALE, we fit their hydrogen line equivalent widths (EWs) and photometric data. We assess the impacts of the removal of spectroscopic data by comparing the quality of the fits of the spectro-photometric data to those with photometric data only. We compare the single (BC03) vs binary (BPASS) stellar populations models in the fitting process of spectro-photometric data. We derive the differential attenuation and explore different attenuation recipes by fitting spectro-photometric data with BC03. For each stellar model and for each input dataset (with and without EWs), we quantify the deviation on the SFRs and stellar masses from the "standard" choice. On average, the SFRs are overestimated and the stellar masses are underestimated when EWs are not included as input data. We find a major contribution of the H${\alpha}$ emission line to the broadband photometric measurements of our sources, and a trend of increasing contribution with specific SFR. Using the BPASS models has a significant impact on the derived SFRs and stellar masses. We show that a flexible attenuation recipe provides more accurate estimates of the dust attenuation parameters, especially the differential attenuation which agrees with the original value of Charlot & Fall (2000)., Comment: Accepted in Astronomy & Astrophysics, 19 pages, 15 figures

In modern computer vision, the optimal representation of 3D shape continues to be task-dependent. One fundamental operation applied to such representations is differentiable rendering, as it enables inverse graphics approaches in learning frameworks. Standard explicit shape representations (voxels, point clouds, or meshes) are often easily rendered, but can suffer from limited geometric fidelity, among other issues. On the other hand, implicit representations (occupancy, distance, or radiance fields) preserve greater fidelity, but suffer from complex or inefficient rendering processes, limiting scalability. In this work, we devise Directed Distance Fields (DDFs), a novel neural shape representation that builds upon classical distance fields. The fundamental operation in a DDF maps an oriented point (position and direction) to surface visibility and depth. This enables efficient differentiable rendering, obtaining depth with a single forward pass per pixel, as well as differential geometric quantity extraction (e.g., surface normals), with only additional backward passes. Using probabilistic DDFs (PDDFs), we show how to model inherent discontinuities in the underlying field. We then apply DDFs to several applications, including single-shape fitting, generative modelling, and single-image 3D reconstruction, showcasing strong performance with simple architectural components via the versatility of our representation. Finally, since the dimensionality of DDFs permits view-dependent geometric artifacts, we conduct a theoretical investigation of the constraints necessary for view consistency. We find a small set of field properties that are sufficient to guarantee a DDF is consistent, without knowing, for instance, which shape the field is expressing., Comment: Extension of arXiv:2112.05300

A new burn control scheme for tokamaks is described where the total fusion power is controlled by adjusting the plasma volume fraction that is packed into power dense regions. In an example spherical tokamak burning plasma, by modifying the plasma edge squareness the total fusion power is doubled at almost constant total plasma volume and fusion power density. Therefore, increased plasma squareness could be extremely beneficial to a fusion reactor and squareness control could be desirable for power load balancing. Experiments have observed the impact of increased edge squareness on modified core plasma volume, highlighting the practical relevance of this approach., Comment: 7 pages, 7 figures

We present a sample of 341 "little red dots" (LRDs) spanning the redshift range $z\sim2-11$ using data from the CEERS, PRIMER, JADES, UNCOVER and NGDEEP surveys. These sources are likely heavily-reddened AGN that trace a previously-hidden phase of dust-obscured black hole growth in the early Universe. Unlike past use of color indices to identify LRDs, we employ continuum slope fitting using shifting bandpasses to sample the same rest-frame emission blueward and redward of the Balmer break. This approach allows us to identify LRDs over a wider redshift range and is less susceptible to contamination from galaxies with strong breaks that otherwise lack a rising red continuum. The redshift distribution of our sample increases at $z<8$ and then undergoes a rapid decline at $z\sim4.5$, which may tie the emergence, and obscuration, of these sources to the inside-out growth that galaxies experience during this epoch. We find that LRDs are 2-3 dex more numerous than bright quasars at $z\sim5-7$, but their number density is only 0.6-1 dex higher than X-ray and UV selected AGN at these redshifts. Within our sample, we have identified the first X-ray detected LRDs at $z=3.1$ and $z=4.66$. An X-ray spectral analysis confirms that these AGN are moderately obscured with $\log\,(N_{\rm H}/{\rm cm}^{2}$) of $23.3^{+0.4}_{-1.3}$ and $22.72^{+0.13}_{-0.16}$. Our analysis reveals that reddened AGN emission dominates their rest-optical light, while the rest-UV originates from their host galaxies. We also present NIRSpec follow-up spectroscopy of 17 LRDs that show broad emission lines consistent with AGN activity. The confirmed AGN fraction of our sample is $71\%$ for sources with F444W$<26.5$. In addition, we find three LRDs with narrow blue-shifted Balmer absorption features in their spectra, suggesting an outflow of high-density, low ionization gas from near the central engine of these faint, red AGN., Comment: 23 pages, 17 figures, submitted to ApJ

We present the first systematic investigation of supervised scaling laws outside of an ImageNet-like context - on images of galaxies. We use 840k galaxy images and over 100M annotations by Galaxy Zoo volunteers, comparable in scale to Imagenet-1K. We find that adding annotated galaxy images provides a power law improvement in performance across all architectures and all tasks, while adding trainable parameters is effective only for some (typically more subjectively challenging) tasks. We then compare the downstream performance of finetuned models pretrained on either ImageNet-12k alone vs. additionally pretrained on our galaxy images. We achieve an average relative error rate reduction of 31% across 5 downstream tasks of scientific interest. Our finetuned models are more label-efficient and, unlike their ImageNet-12k-pretrained equivalents, often achieve linear transfer performance equal to that of end-to-end finetuning. We find relatively modest additional downstream benefits from scaling model size, implying that scaling alone is not sufficient to address our domain gap, and suggest that practitioners with qualitatively different images might benefit more from in-domain adaption followed by targeted downstream labelling., Comment: 10+6 pages, 12 figures. Appendix C2 based on arxiv:2206.11927. Code, demos, documentation at https://github.com/mwalmsley/zoobot

The steady flow of social-media cases toward the Supreme Court shows a nation reworking its fundamental relationship with technology. The cases raise a host of questions ranging from difficult to impossible: how to nurture a vibrant public square when a few tech giants dominate the flow of information, how social media can be at the same time free from conformist groupthink and also protected against harmful disinformation campaigns, and how government and industry can cooperate on such problems without devolving toward censorship. To such profound questions, this Essay offers a comparatively modest contribution -- what not to do. Always the lawyer's instinct is toward analogy, considering what has come before and how it reveals what should come next. Almost invariably, that is the right choice. The law's cautious evolution protects society from disruptive change. But almost is not always, and, with social media, disruptive change is already upon us. Using social-media laws from Texas and Florida as a case study, this Essay shows how social-media's distinct features render it poorly suited to analysis by analogy and argues that courts should instead shift their attention toward crafting legal doctrines targeted to address social media's unique ills.

GHZ2/GLASS-z12 has been recently observed by JWST with both NIRSpec and MIRI spectrographs, making it the most distant galaxy ($z_{spec}=12.34$) with complete spectroscopic coverage from rest-frame UV to optical. It is identified as a strong CIV$_{1549}$ emitter with many detected emission lines (NIV], HeII, OIII], NIII], CIII], [OII], [NeIII], [OIII], and H$\alpha$), including a remarkable OIII$_{1333}$ Bowen fluorescence line. We analyze in this paper the joint NIRSpec+MIRI spectral data set. Combining six optical diagnostics (R2, R3, R23, O32, Ne3O2, and Ne3O2Hd), we find extreme ionization conditions, with O32 $=1.39 \pm 0.19$ and Ne3O2 $=0.37 \pm 0.18$ in stark excess compared to typical values in the ISM at lower redshifts. These line properties are compatible either with an AGN or with a compact, dense star-forming environment ($\Sigma_{\rm SFR}$ $\sim 10^2$-$10^3$ Msun/yr/kpc$^2$), with a high ionization parameter ($\log_{10}$(U) $=-1.75 \pm 0.16$), a high ionizing photon production efficiency $\log(\xi_{\rm ion}) = 25.7_{-0.1}^{+0.2}$, and a low, although not pristine, metal content between $5\%$ and $11\%$ Z$_\odot$ (confirmed by the T$_e$ method), indicating a rapid metal enrichment in the last few Myrs. These properties also suggest that a substantial amount of ionizing photons ($\sim 10\%$) are leaking outside. The general lessons learned from GHZ2 are the following: (i) the UV to optical combined nebular indicators are broadly in agreement with UV-only or optical-only indicators. (ii) UV+optical diagnostics fail to discriminate between an AGN and star-formation in a low metallicity, high density, and extreme ionization environment. (iii) comparing the nebular line ratios with local analogs may be approaching its limits at $z \gtrsim 10$, as this approach is potentially challenged by the unique conditions of star formation experienced by galaxies at these extreme redshifts., Comment: 14 pages, 3 figures, and 1 table. Resubmitted to ApJ. A section (3.4) has been added to the previous version

The James Webb Space Telescope (JWST) has discovered a surprising population of bright galaxies in the very early universe (< 500 Myrs after the Big Bang) that is hard to explain with conventional galaxy formation models and whose physical properties remain to be fully understood. Insight into the internal physics of galaxies is captured best via observations of excited-state atomic transitions of ionized gas, but beyond z~7-9, the brightest spectral signatures are redshifted into the mid-infrared regime, where observations are increasingly more difficult. Here, we present the first detection of a hydrogen recombination line (H{\alpha}) and doubly-ionized oxygen ([OIII]4959,5007{\AA}) at z>10 using the JWST Mid-Infrared Instrument, MIRI. These detections place the bright galaxy GHZ2/GLASS-z12 at z=12.33+/-0.02, making it the most distant astronomical object with direct spectroscopic detection of these lines and the brightest confirmed object at this epoch. These observations provide key insights into the conditions of this primeval galaxy, which shows hard ionizing conditions rarely seen in the local Universe and likely driven by compact, young (<30 Myr) star formation. Its oxygen-to-hydrogen abundance is close to a tenth of the solar value, indicating a rapid metal enrichment during the earliest phases of galaxy formation. This study confirms the unique conditions of the brightest and most distant galaxies recently discovered by JWST and the huge potential of mid-IR observations to characterize these systems, opening a range of new possibilities in the study of the very early Universe., Comment: 14 pages, 6 figures. Submitted for publication. Comments are most welcome

We spectroscopically confirm the $M_{\rm UV} = -20.5$ mag galaxy GHZ2/GLASS-z12 to be at redshift $z=12.34$. The source was selected via NIRCam photometry in GLASS-JWST ERS data, providing the first evidence of a surprising abundance of bright galaxies at $z \gtrsim 10$. The NIRSpec PRISM spectrum shows detections of N IV, C IV, He II, O III, C III, O II, and Ne III lines, and the first detection at high-redshift of the O III Bowen fluorescence line at 3133 {\AA} rest-frame. The prominent C IV line with rest-frame equivalent width (EW) $\approx 46$ {\AA} puts GHZ2 in the category of extreme C IV emitters. GHZ2 displays UV lines with EWs that are only found in active galactic nuclei (AGNs) or composite objects at low/intermediate redshifts. The UV line-intensity ratios are compatible both with AGNs and star formation in a low-metallicity environment, with the low limit on the [Ne IV]/[N IV] ratio favoring a stellar origin of the ionizing photons. We discuss a possible scenario in which the high ionizing output is due to low metallicity stars forming in a dense environment. We estimate a metallicity $\lesssim 0.1 Z/{\rm Z}_{\odot}$, a high ionization parameter logU $> -2$, a N/O abundance 4--5 times the solar value, and a subsolar C/O ratio similar to the recently discovered class of nitrogen-enhanced objects. Considering its abundance patterns and the high stellar mass density ($10^4$~M$_{\odot}$~pc$^{-2}$), GHZ2 is an ideal formation site for the progenitors of today's globular clusters. The remarkable brightness of GHZ2 makes it a ``Rosetta stone'' for understanding the physics of galaxy formation within just 360 Myr after the Big Bang., Comment: Accepted for publication in The Astrophysical Journal. 20 pages, 7 figures, 2 tables

Age-dating and weighting stellar populations in galaxies are essential steps to study galaxy formation through cosmic times. Evolutionary population synthesis models with different input physics are used towards this aim. In particular, the contribution from the thermally pulsing asymptotic giant branch (TP-AGB) stellar phase, which peaks for intermediate-age 0.6-2 Gyr systems, has been debated upon for decades. Here we report the detection of strong cool-star signatures in the rest-frame near-infrared spectra of three young (~1 Gyr), massive (~10^10 Msun) quiescent galaxies at large look-back time, z=1-2, using JWST/NIRSpec. The co-existence of oxygen- and carbon-type absorption features, spectral edges and features from rare species such as Vanadium, and possibly Zirconium, reveal a strong contribution from TP-AGB stars. Population synthesis models with significant TP-AGB contribution reproduce the observations better than those with weak TP-AGB, which are commonly used. These findings call for revisions of published stellar population fitting results, pointing to lower masses and younger ages, with additional implications on cosmic dust production and chemical enrichment. New generations of improved models are needed, informed by these and future observations., Comment: Nature Astronomy, in press

Extreme emission line galaxies (EELGs) are typically characterized by high equivalent widths (EWs) which are driven by elevated specific star formation rates (sSFR) in low-mass galaxies with subsolar metallicities and little dust. Such extreme systems are rare in the local universe, but the number density of EELGs increases with redshift. Such starburst galaxies are currently presumed to be the main drivers of hydrogen reionization over 5.50.4-1 which indicates that star formation may be the dominant source of ionization. Based on the photometric fluxes, we find an increase of EW([OIII]+H$\beta$) with sSFR and $\Sigma_{SFR}$, and a decrease with age and stellar mass. The sample of EELGs can reach $\Sigma_{SFR}>$10Msun yr$^{-1}$kpc$^{-2}$ which indicate they are strong candidates of LyC leakers. Another indirect indicator is the high values of O32>5 that can be reached for some galaxies in the sample., Comment: Accepted for publication in A&A. We updated the manuscript following referee's suggestions

The galaxy integrated star-formation rate (SFR) surface density ($\Sigma_{\rm SFR}$) has been proposed as a valuable diagnostic of the mass accumulation in galaxies as being more tightly related to the physics of star-formation (SF) and stellar feedback than other SF indicators. In this paper, we assemble a statistical sample of 230 galaxies observed with JWST in the GLASS and CEERS spectroscopic surveys to estimate Balmer line based dust attenuations and SFRs, and UV rest-frame effective radii. We study the evolution of galaxy SFR and $\Sigma_{\rm SFR}$ in the first 1.5 Billion years of our Universe, finding that $\Sigma_{\rm SFR}$ is mildly increasing with redshift with a linear slope of $0.16 \pm 0.06$. We also explore the dependence of SFR and $\Sigma_{\rm SFR}$ on stellar mass, showing that a SF 'Main-Sequence' and a $\Sigma_{\rm SFR}$ `Main-Sequence' are in place out to z=10, with a similar slope compared to the same relations at lower redshifts. We find that the specific SFR (sSFR) and $\Sigma_{\rm SFR}$ are correlated with the [OIII]5007/[OII]3727 ratio and with indirect estimates of the escape fraction of Lyman continuum photons, hence they likely play an important role in the evolution of ionization conditions and in the escape of ionizing radiation. We also search for spectral outflow signatures in a subset of galaxies observed at high resolution, finding an outflow incidence of $2/11$ ($=20\%^{32\%}_{9\%}$) at $z<6$, but no evidence at $z>6$ ($<26\%$). Finally, we find a positive correlation between A$_V$ and $\Sigma_{\rm SFR}$, and a flat trend as a function of sSFR, indicating that there is no evidence of a drop of A$_V$ in extremely star-forming galaxies between z=4 and 10. This might be at odds with a dust-clearing outflow scenario, which might instead take place at redshifts $z\geq 10$, as suggested by some theoretical models., Comment: Accepted for publication in A&A ; 19 pages, 9 figures, 1 table. Compared to the previous version, we have corrected a typo in Fig. 5 (the x and y axis labels were inverted)

The resonant scattering interaction between Ly$\alpha$ photons and neutral hydrogen implies that a partially neutral IGM can significantly impact the detectability of Ly$\alpha$ emission in galaxies. The redshift evolution of the Ly$\alpha$ equivalent width distribution of galaxies thus offers a key probe of the degree of ionization during the Epoch of Reionization (EoR). Previous in-depth investigations at $z$ $\geq$ 7 were limited by ground-based instrument capabilities. We present an extensive study of Ly$\alpha$ emission from galaxies at 4 < $z$ < 8.5, observed from the CEERS and JADES surveys in the JWST NIRSpec/PRISM configuration. The sample consists of 235 galaxies, among which we identify 65 as Ly$\alpha$ emitters. We first measure Ly$\alpha$ escape fractions from Balmer lines, and explore the correlations with the inferred galaxies' physical properties, which are similar to those found at lower redshift. We also investigate the possible connection between the escape of Ly$\alpha$ photons and the inferred escape fractions of LyC photons obtained from indirect indicators. We then analyze the redshift evolution of the Ly$\alpha$ emitter fraction, finding lower average values at $z$ = 5 and 6 compared to ground-based observations. At $z$ = 7 we find a very large difference in Ly$\alpha$ visibility between the EGS and GOODS-South fields, possibly due to the presence of early reionized regions in the EGS. Such large variance is also expected in the Cosmic Dawn II radiation-hydrodynamical simulation. Our findings suggest a scenario in which the ending phase of the EoR is characterized by $\sim$ 1 pMpc ionized bubbles around a high fraction of moderately bright galaxies. Finally, we characterize such two ionized regions found in the EGS at $z$ = 7.18 and $z$ = 7.49 by estimating the radius of the ionized bubble that each of the spectroscopically-confirmed members could have created., Comment: Submitted to A&A

[ABRIDGED] This paper discusses the importance of parallel perturbations of the magnetic-field in gyrokinetic simulations of electromagnetic instabilities and turbulence at mid-radius in the burning plasma phase of the conceptual high-$\beta$, reactor-scale, tight-aspect-ratio tokamak STEP. Previous studies have revealed the presence of unstable hybrid kinetic ballooning modes (hKBMs) at binormal scales approaching the ion Larmor radius. In this STEP plasma it was found that the hKBM requires the inclusion of parallel magnetic-field perturbations to be linearly unstable. Here, the extent to which the inclusion of fluctuations in the parallel magnetic-field can be relaxed is explored through gyrokinetic simulations. In particular, the frequently used MHD approximation (dropping $\delta \! B_{\parallel}$ and setting the $\nabla B$ drift frequency equal to the curvature drift frequency) is discussed and simulations explore whether this approximation is useful for modelling STEP plasmas. It is shown that the MHD approximation can reproduce some of the linear properties of the full STEP gyrokinetic system, but is too stable at low $k_y$ and nonlinear simulations using the MHD approximation result in very different transport states. It is demonstrated that the MHD approximation is challenged by the high $\beta^{\prime}$ values in STEP, and that the approximation improves considerably at lower $\beta^{\prime}$. Furthermore, it is shown that the sensitivity of STEP to $\delta \! B_{\parallel}$ fluctuations is primarily because the plasma sits close to marginality and it is shown that in slightly more strongly driven conditions the hKBM is unstable without $\delta \! B_{\parallel}.$ Crucially, it is demonstrated that the state of large transport typically predicted by local electromagnetic gyrokinetic simulations of STEP plasmas is not solely due to $\delta \! B_{\parallel}$ physics., Comment: 29th IAEA FEC conference

Many diagnostic errors occur because clinicians cannot easily access relevant information in patient Electronic Health Records (EHRs). In this work we propose a method to use LLMs to identify pieces of evidence in patient EHR data that indicate increased or decreased risk of specific diagnoses; our ultimate aim is to increase access to evidence and reduce diagnostic errors. In particular, we propose a Neural Additive Model to make predictions backed by evidence with individualized risk estimates at time-points where clinicians are still uncertain, aiming to specifically mitigate delays in diagnosis and errors stemming from an incomplete differential. To train such a model, it is necessary to infer temporally fine-grained retrospective labels of eventual "true" diagnoses. We do so with LLMs, to ensure that the input text is from before a confident diagnosis can be made. We use an LLM to retrieve an initial pool of evidence, but then refine this set of evidence according to correlations learned by the model. We conduct an in-depth evaluation of the usefulness of our approach by simulating how it might be used by a clinician to decide between a pre-defined list of differential diagnoses.