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Massive, intensely star-forming galaxies at high redshift require a supply of molecular gas from their gas reservoirs, replenished by infall from the surrounding circumgalactic medium, to sustain their immense star-formation rates. However, our knowledge of the extent and morphology of their cold-gas reservoirs is still in its infancy. We present the results of stacking 80 hours of JVLA observations of CO(1--0) emission -- which traces the cold molecular gas -- in 19 $z=2.0-4.5$ dusty, star-forming galaxies from the AS2VLA survey. The visibility-plane stack reveals extended emission with a half-light radius of $3.8\pm0.5$~kpc, 2--3$\times$ more extended than the dust-obscured star formation and $1.4\pm0.2\times$ more extended than the stellar emission. Similarly, stacking the [CI](1--0) observations for a subsample of our galaxies yields sizes consistent with CO(1--0). The CO(1--0) size is comparable to the [CII] halos detected around high-redshift star-forming galaxies.The bulk (up to 80\%) of molecular gas resides outside the star-forming region; only a small part of their molecular gas reservoir directly contributes to their current star formation. Photon-dissociation region modelling indicates that the extended CO(1--0) emission arises from clumpy, dense clouds rather than smooth, diffuse gas., Comment: Submitted to A&A. 9 pages, 5 figures

This paper explores the mechanical behaviour of the composite materials used in modern lithium-ion battery electrodes. These contain relatively high modulus active particle inclusions within a two-component matrix of liquid electrolyte which penetrates the pore space within a viscoelastic polymer binder. Deformations are driven by a combination of (i) swelling/contraction of the electrode particles in response to lithium insertion/extraction, (ii) swelling of the binder as it absorbs electrolyte, (iii) external loading and (iv) flow of the electrolyte within the pores. We derive the macroscale response of the composite using systematic multiple scales homomgenisation by exploiting the disparity in lengthscales associated with the size of an electrode particle and the electrode as a whole. The resulting effective model accurately replicates the behaviour of the original model (as is demonstrated by a series of relevant case studies) but, crucially, is markedly {simpler and hence} cheaper to solve. This is significant practical value because it facilitates low-cost, realistic computations of the mechanical states of battery electrodes, thereby allowing model-assisted development of battery designs that are better able to withstand the mechanical abuse encountered in practice and ultimately paving the way for longer-lasting batteries., Comment: 46 pages, 19 figures

We present a new method for modelling the kinematics of galaxies from interferometric observations by performing the optimization of the kinematic model parameters directly in visibility-space instead of the conventional approach of fitting velocity fields produced with the CLEAN algorithm in real-space. We demonstrate our method on ALMA observations of $^{12}$CO (2$-$1), (3$-$2) or (4$-$3) emission lines from an initial sample of 30 massive 850$\mu$m-selected dusty star-forming galaxies with far-infrared luminosities $\gtrsim$$\,10^{12}\,$L$_{\odot}$ in the redshift range $z \sim\,$1.2$-$4.7. Using the results from our modelling analysis for the 12 sources with the highest signal-to-noise emission lines and disk-like kinematics, we conclude the following: (i) Our sample prefers a CO-to-$H_2$ conversion factor, of $\alpha_{\rm CO} = 0.92 \pm 0.36$; (ii) These far-infrared luminous galaxies follow a similar Tully$-$Fisher relation between the circularized velocity, $V_{\rm circ}$, and baryonic mass, $M_{\rm b}$, as more typical star-forming samples at high redshift, but extend this relation to much higher masses $-$ showing that these are some of the most massive disk-like galaxies in the Universe; (iii) Finally, we demonstrate support for an evolutionary link between massive high-redshift dusty star-forming galaxies and the formation of local early-type galaxies using the both the distributions of the baryonic and kinematic masses of these two populations on the $M_{\rm b}\,-\,\sigma$ plane and their relative space densities.

Singularly-perturbed ordinary differential equations often exhibit Stokes' phenomenon, which describes the appearance and disappearance of oscillating exponentially small terms across curves in the complex plane known as Stokes curves. These curves originate at singular points in the leading-order solution to the differential equation. In many important problems, it is impossible to obtain a closed-form expression for these leading-order solutions, and it is therefore challenging to locate these singular points. We present evidence that the analytic leading-order solution of a linear differential equation can be replaced with a rational approximation based on a numerical leading-order solution using the adaptive Antoulas-Anderson (AAA) method. We show that the subsequent exponential asymptotic analysis accurately predicts the exponentially small behaviour present in the solution. We explore the limitations of this approach, and show that for sufficiently small values of the asymptotic parameter, this approach breaks down; however, the range of validity may be extended by increasing the number of poles in the rational approximation. We finish by presenting a related nonlinear problem and discussing the challenges that arise when attempting to apply this method to nonlinear problems., Comment: 20 pages, 8 figures, 3 tables

In the present work we revisit the problem of the generalized Korteweg-de Vries equation parametrically, as a function of the relevant nonlinearity exponent, to examine the emergence of blow-up solutions, as traveling waveforms lose their stability past a critical point of the relevant parameter $p$, here at $p=5$. We provide a {\it normal form} of the associated collapse dynamics and illustrate how this captures the collapsing branch bifurcating from the unstable traveling branch. We also systematically characterize the linearization spectrum of not only the traveling states, but importantly of the emergent collapsing waveforms in the so-called co-exploding frame where these waveforms are identified as stationary states. This spectrum, in addition to two positive real eigenvalues which are shown to be associated with the symmetries of translation and scaling invariance of the original (non-exploding) frame features complex patterns of negative eigenvalues that we also fully characterize. We show that the phenomenology of the latter is significantly affected by the boundary conditions and is far more complicated than in the corresponding symmetric Laplacian case of the nonlinear Schr{\"o}dinger problem that has recently been explored. In addition, we explore the dynamics of the unstable solitary waves for $p>5$ in the co-exploding frame., Comment: 33 pages, 16 figures

The nature and evolution of high-redshift dusty star-forming galaxies (high-z DSFGs) remain an open question. Their massive gas reservoirs play an important role in driving the intense star-formation rates hosted in these galaxies. We aim to estimate the molecular gas content of high-z DSFGs by using various gas mass tracers such as the [CI], CO, [CII] emission lines and the dust content. These tracers need to be well calibrated as they are all limited by uncertainties on factors such as aCO, XCI, aCII and GDR, thereby affecting the determination of the gas mass accurately. The main goal of our work is to check the consistency between the gas mass tracers and cross-calibrate the uncertain factors. We observe the two [CI] line transitions for 29 SPT-SMGs with the ALMA-ACA. Additionally, we also present new APEX observations of [CII] line for 9 of these galaxies. We find a nearly linear relation between the infrared luminosity and [CI] luminosity if we fit the starbursts and main-sequence galaxies separately. We measure a median [CI]-derived excitation temperature of 34.5+/-2.1 K. We probe the properties of the interstellar medium (ISM) such as density and radiation field intensity using [CI] to mid- or high-J CO lines and [CI] to infrared luminosity ratio, and find similar values to the SMG populations in literature. Finally, the gas masses estimated from [CI], CO, dust, and [CII] do not exhibit any significant trend with the infrared luminosity or the dust temperature. We provide the various cross-calibrations between these tracers. Our study confirms that [CI] is a suitable tracer of the molecular gas content, and shows an overall agreement between all the classical gas tracers used at high redshift. However, their absolute calibration and thus the gas depletion timescale measurements remain uncertain., Comment: Accepted for publication in A&A, 25 pages, 11 figures, 6 tables

Asymptotic homogenisation is considered for problems with integral constraints imposed on a slowly-varying microstructure; an insulator with an array of perfectly dielectric inclusions of slowly varying size serves as a paradigm. Although it is well-known how to handle each of these effects (integral constraints, slowly-varying microstructure) independently within multiple scales analysis, additional care is needed when they are combined. Using the flux transport theorem, the multiple scales form of an integral constraint on a slowly varying domain is identified. The proposed form is applied to obtain a homogenised model for the electric potential in a dielectric composite, where the microstructure slowly varies and the integral constraint arises due to a statement of charge conservation. A comparison with multiple scales analysis of the problem with established approaches provides validation that the proposed form results in the correct homogenised model., Comment: 15 pages, 2 figures

We examine a misleadingly simple linear second-order eigenvalue problem (the Hermite-with-pole equation) that was previously proposed as a model problem of an equatorially-trapped Rossby wave. In the singularly perturbed limit representing small latitudinal shear, the eigenvalue contains an exponentially-small imaginary part; the derivation of this component requires exponential asymptotics. In this work, we demonstrate that the problem contains a number of pathological elements in exponential asymptotics that were not remarked upon in the original studies. This includes the presence of dominant divergent eigenvalues, non-standard divergence of the eigenfunctions, and inactive Stokes lines due to the higher-order Stokes phenomenon. The techniques developed in this work can be generalised to other linear or nonlinear eigenvalue problems involving asymptotics beyond-all-orders where such pathologies are present., Comment: 21 pages, 3 figures

We present spatially resolved kinematics of 27 ALMA-identified dust-obscured star-forming galaxies (DSFGs) at $z\sim$1.3-2.6, as traced by H$\alpha$ emission using VLT/KMOS near-infrared integral field spectroscopy from the "KMOS-ALMA Observations of Submillimetre Sources" (KAOSS) Large Programme. We derive H$\alpha$ rotation curves and velocity dispersion profiles for the DSFGs, and find that among the 27 sources with bright, spatially extended H$\alpha$ emission, 24 display evidence for disc-like kinematics. We measure a median inclination-corrected velocity at 2.2$R_{\rm d}$ of $v_{\rm rot}=$190$\pm$40kms$^{-1}$ and intrinsic velocity dispersion of $\sigma_0=$87$\pm$6kms$^{-1}$ for these disc-like sources. The kinematics yield median circular velocities of $v_{\rm circ}=$230$\pm$20kms$^{-1}$ and dynamical masses within 2$R_{\rm e}$ ($\sim$7kpc radius) of $M_{\rm dyn}=$(1.1$\pm$0.2)$\times$10$^{11}$M$_\odot$. Compared to less actively star-forming galaxies, KAOSS DSFGs are both faster rotating with higher intrinsic velocity dispersions, but have similar $v_{\rm rot}/\sigma_0$ ratios, median $v/\sigma_0=$2.5$\pm$0.5. We suggest that the kinematics of the DSFGs are primarily rotation supported but with a non-negligible contribution from pressure support, which may be driven by star formation or mergers/interactions. We estimate the normalisation of the stellar mass Tully-Fisher relation (sTFR) for the disc-like DSFGs and compare it with local studies, finding no evolution at fixed slope between $z\sim$2 and $z\sim$0. Finally, we show that the kinematic properties of the DSFG population are consistent with them evolving into massive early-type galaxies, the dominant $z\sim$0 population at these masses., Comment: 24 pages, 15 figures, accepted for publication in MNRAS, updated author list

We present the average rest-frame spectrum of the final catalog of dusty star-forming galaxies (DSFGs) selected from the South Pole Telescope SZ survey (SPT-SZ) and measured with Band 3 of the Atacama Large Millimeter/submillimeter Array (ALMA). This work builds on the previous average rest-frame spectrum, given in Spilker et al. (2014) for the first 22 sources, and is comprised of a total of 78 sources, normalized by their respective apparent dust masses. The spectrum spans $1.9$$<$z$<$$6.9$ and covers rest-frame frequencies of 240$-$800 GHz. Combining this data with low-J CO observations from the Australia Telescope Compact Array (ATCA), we detect multiple bright line features from $^{12}$CO, $[$CI$]$, and H$_2$O, as well as fainter molecular transitions from $^{13}$CO, HCN, HCO$^+$, HNC, CN, H$_2$O$^+$, and CH. We use these detections, along with limits from other molecules, to characterize the typical properties of the interstellar medium (ISM) for these high redshift DSFGs. We are able to divide the large sample into subsets in order to explore how the average spectrum changes with various galaxy properties, such as effective dust temperature. We find that systems with hotter dust temperatures exhibit differences in the bright $^{12}$CO emission lines, and contain either warmer and more excited dense gas tracers, or larger dense gas reservoirs. These observations will serve as a reference point to studies of the ISM in distant luminous DSFGs (L$_{\mathrm{IR}}$$>$$10^{12}$L$_\odot$), and will inform studies of chemical evolution before the peak epoch of star formation at $z=2-3$., Comment: 26 pages, 10 figures, accepted for publication in ApJ

We present the resolved properties of the $z=2.82$ Hyper Luminous Infrared Galaxy (HyLIRG) HS170850.1, the brightest 850$\mu$m source found in the SCUBA-2 followup to the Keck Baryonic Structure Survey fields (S$_{\rm 850 \mu m}=$19.5 mJy), and amongst the most luminous starbursts known at any redshift. Using the IRAM-NOEMA interferometer in the highest resolution A-configuration, we resolve the source into two components separated by $\sim$8 kpc, visible as blue shifted and red shifted $^{12}$CO(5-4) lines, exhibiting the expected kinematic properties of a major merger between two gas-rich galaxies. The combined merger system is traced over 2.3$''$ or 18.3 kpc. Each component of the merger shows ordered gas motions suggestive of a massive, turbulent disk. We measure the masses of the blue and red disks as (1.5 $\pm$ 0.2) $\times10^{11}$ M$_\odot$ and (0.71 $\pm$ 0.22) $\times10^{11}$ M$_\odot$ respectively. The more massive disk component shows broad wings in the CO line, offset by $\sim$3 kpc from the disk centroid along the major axis, and extending to velocities $\sim\pm$1000 km $ \rm{s^{-1}}$ from systemic velocity. We interpret this as either a possible bipolar outflowing component, or more likely a warping or tidal structure in the CO disk. Comparing the properties of HS170850.1 to other submillimeter detected galaxies with comparably bright 850$\mu$m luminosities suggests that ongoing gas-rich mergers, or at least a clustered/group environment lead to these most extreme starburst phases., Comment: 13 pages, 5 Figures, 2 Tables

We present on the status of POLARBEAR-2 A (PB2-A) focal plane fabrication. The PB2-A is the first of three telescopes in the Simon Array (SA), which is an array of three cosmic microwave background (CMB) polarization sensitive telescopes located at the POLARBEAR (PB) site in Northern Chile. As the successor to the PB experiment, each telescope and receiver combination is named as PB2-A, PB2-B, and PB2-C. PB2-A and -B will have nearly identical receivers operating at 90 and 150 GHz while PB2-C will house a receiver operating at 220 and 270 GHz. Each receiver contains a focal plane consisting of seven close-hex packed lenslet coupled sinuous antenna transition edge sensor bolometer arrays. Each array contains 271 di-chroic optical pixels each of which have four TES bolometers for a total of 7588 detectors per receiver. We have produced a set of two types of candidate arrays for PB2-A. The first we call Version 11 (V11) and uses a silicon oxide (SiOx) for the transmission lines and cross-over process for orthogonal polarizations. The second we call Version 13 (V13) and uses silicon nitride (SiNx) for the transmission lines and cross-under process for orthogonal polarizations. We have produced enough of each type of array to fully populate the focal plane of the PB2-A receiver. The average wirebond yield for V11 and V13 arrays is 93.2% and 95.6% respectively. The V11 arrays had a superconducting transition temperature (Tc) of 452 +/- 15 mK, a normal resistance (Rn) of 1.25 +/- 0.20 Ohms, and saturations powers of 5.2 +/- 1.0 pW and 13 +/- 1.2 pW for the 90 and 150 GHz bands respectively. The V13 arrays had a superconducting transition temperature (Tc) of 456 +/-6 mK, a normal resistance (Rn) of 1.1 +/- 0.2 Ohms, and saturations powers of 10.8 +/- 1.8 pW and 22.9 +/- 2.6 pW for the 90 and 150 GHz bands respectively.

In this work we analyse the local nonlinear electrochemical impedance spectroscopy (NLEIS) response of a lithium-ion battery and estimate model parameters from measured NLEIS data. The analysis assumes a single-particle model including nonlinear diffusion of lithium within the electrode particles and asymmetric charge transfer kinetics at their surface. Based on this model and assuming a moderately-small excitation amplitude, we systematically derive analytical formulae for the impedances up to the second harmonic response, allowing the meaningful interpretation of each contribution in terms of physical processes and nonlinearities in the model. The implications of this for parameterization are explored, including structural identifiability analysis and parameter estimation using maximum likelihood, with both synthetic and experimentally measured impedance data. Accurate fits to impedance data are possible, however inconsistencies in the fitted diffusion timescales suggest that a nonlinear diffusion model may not be appropriate for the cells considered. Model validation is also demonstrated by predicting time-domain voltage response using the parameterized model and this is shown to have excellent agreement with measured voltage time-series data (11.1 mV RMSE)., Comment: 40 pages (excluding supplementary material). Submitted to the Journal of the Electrochemical Society

We study the role of anisotropic steric interactions in a system of hard Brownian needles. Despite having no volume, non-overlapping needles exclude a volume in configuration space that influences the macroscopic evolution of the system. Starting from the stochastic particle system, we use the method of matched asymptotic expansions and conformal mapping to systematically derive a nonlinear nonlocal partial differential equation for the evolution of the population density in position and orientation. We consider the regime of high rotational diffusion, resulting in an equation for the spatial density that allows us to compare the effective excluded volume of a hard-needles system with that of a hard-spheres system. We further consider spatially homogeneous solutions and find an isotropic to nematic transition as density increases, consistent with Onsager's theory.

We present the conceptual design of the modular detector and readout system for the Cosmic Microwave Background Stage 4 (CMB-S4) ground-based survey experiment. CMB-S4 will map the cosmic microwave background (CMB) and the millimeter-wave sky to unprecedented sensitivity, using 500,000 superconducting detectors observing from Chile and Antarctica to map over 60 percent of the sky. The fundamental building block of the detector and readout system is a detector module package operated at 100 mK, which is connected to a readout and amplification chain that carries signals out to room temperature. It uses arrays of feedhorn-coupled orthomode transducers (OMT) that collect optical power from the sky onto dc-voltage-biased transition-edge sensor (TES) bolometers. The resulting current signal in the TESs is then amplified by a two-stage cryogenic Superconducting Quantum Interference Device (SQUID) system with a time-division multiplexer to reduce wire count, and matching room-temperature electronics to condition and transmit signals to the data acquisition system. Sensitivity and systematics requirements are being developed for the detector and readout system over a wide range of observing bands (20 to 300 GHz) and optical powers to accomplish CMB-S4's science goals. While the design incorporates the successes of previous generations of CMB instruments, CMB-S4 requires an order of magnitude more detectors than any prior experiment. This requires fabrication of complex superconducting circuits on over 10 square meters of silicon, as well as significant amounts of precision wiring, assembly and cryogenic testing., Comment: 25 pages, 15 figures, presented at and published in the proceedings of SPIE Astronomical Telescopes and Instrumentation 2022

We present the multi-wavelength counterparts of 850-$\mu$m selected submillimetre sources over a 2-deg$^2$ field centred on the North Ecliptic Pole. In order to overcome the large beam size (15 arcsec) of the 850-$\mu$m images, deep optical to near-infrared (NIR) photometric data and arcsecond-resolution 20-cm images are used to identify counterparts of submillimetre sources. Among 647 sources, we identify 514 reliable counterparts for 449 sources (69 per cent in number), based either on probabilities of chance associations calculated from positional offsets or offsets combined with the optical-to-NIR colours. In the radio imaging, the fraction of 850-$\mu$m sources having multiple counterparts is 7 per cent. The photometric redshift, infrared luminosity, stellar mass, star-formation rate (SFR), and the AGN contribution to the total infrared luminosity of the identified counterparts are investigated through spectral energy distribution fitting. The SMGs are infrared-luminous galaxies at an average $\langle z\rangle=2.5$ with $\mathrm{log}_{10} (L_\mathrm{IR}/\mathrm{L}_\odot)=11.5-13.5$, with a mean stellar mass of $\mathrm{log}_{10} (M_\mathrm{star}/\mathrm{M}_\odot)=10.90$ and SFR of $\mathrm{log}_{10} (\mathrm{SFR/M_\odot\,yr^{-1}})=2.34$. The SMGs show twice as large SFR as galaxies on the star-forming main sequence, and about 40 per cent of the SMGs are classified as objects with bursty star formation. At $z\ge4$, the contribution of AGN luminosity to total luminosity for most SMGs is larger than 30 per cent. The FIR-to-radio correlation coefficient of SMGs is consistent with that of main-sequence galaxies at $z\simeq2$., Comment: 24 pages, 16 figures. Accepted for publication in MNRAS

We report an improved measurement of the degree-scale cosmic microwave background $B$-mode angular-power spectrum over 670 square-degree sky area at 150 GHz with POLARBEAR. In the original analysis of the data, errors in the angle measurement of the continuously rotating half-wave plate, a polarization modulator, caused significant data loss. By introducing an angle-correction algorithm, the data volume is increased by a factor of 1.8. We report a new analysis using the larger data set. We find the measured $B$-mode spectrum is consistent with the $\Lambda$CDM model with Galactic dust foregrounds. We estimate the contamination of the foreground by cross-correlating our data and Planck 143, 217, and 353 GHz measurements, where its spectrum is modeled as a power law in angular scale and a modified blackbody in frequency. We place an upper limit on the tensor-to-scalar ratio $r$ < 0.33 at 95% confidence level after marginalizing over the foreground parameters., Comment: 16 pages, 9 figures, 8 tables, Published in ApJ

A homogenised model is developed to describe the interaction between aligned strings and an incompressible, viscous, Newtonian fluid. In the case of many strings, the ratio of string separation to domain width gives a small parameter which can be exploited to simplify the problem. Model derivation using multiscale asymptotics results in a modified Darcy law for fluid flow, with coefficients determined by averaged solutions to microscale problems. Fluid flow is coupled to solid deformation via a homogenised force balance obtained by coarse-graining the balance on each string. This approach offers an alternative method to systematically derive the equations governing the interaction of Stokes flow with many flexible structures. The resulting model of fluid-structure interaction is reduced to a single scalar, linear, partial differential equation by introducing a potential for the pressure. Analytical solutions are presented for a cylindrical geometry subject to time harmonic motion of the string ends. Scaling laws are identified that describe the variation of shear stress exerted on the string surface with the forcing frequency., Comment: 26 pages, 6 figures

The nonlinear Schroedinger model is a prototypical dispersive wave equation that features finite time blowup, either for supercritical exponents (for fixed dimension) or for supercritical dimensions (for fixed nonlinearity exponent). Upon identifying the self-similar solutions in the so-called "co-exploding frame", a dynamical systems analysis of their stability is natural, yet is complicated by the mixed Hamiltonian-dissipative character of the relevant frame. In the present work, we study the spectral picture of the relevant linearized problem. We examine the point spectrum of 3 eigenvalue pairs associated with translation, $U(1)$ and conformal invariances, as well as the continuous spectrum. We find that two eigenvalues become positive, yet are attributed to symmetries and are thus not associated with instabilities. In addition to a vanishing eigenvalue, 3 more are found to be negative and real, while the continuous spectrum is nearly vertical and on the left-half (spectral) plane. Finally, the subtle effects of the boundaries are also assessed and their role in the observed weak eigenvalue oscillations is clarified.

We introduce an ALMA band 3 spectroscopic survey, targeting the brightest submillimeter galaxies (SMGs) in the COSMOS field. Here we present the first results based on the 18 primary SMGs that have 870 $\mu$m flux densities of $S_{870}=12.4-19.3$ mJy and are drawn from a parent sample of 260 ALMA-detected SMGs from the AS2COSMOS survey. We detect emission lines in 17 and determine their redshifts to be in the range of $z=2-5$ with a median of ${3.3\pm0.3}$. We confirm that SMGs with brighter $S_{870}$ are located at higher redshifts. The data additionally cover five fainter companion SMGs, and we obtain line detection in one. Together with previous studies, our results indicate that for SMGs that satisfy our selection, their brightest companion SMGs are physically associated with their corresponding primary SMGs in $\ge40$% of the time, suggesting that mergers play a role in the triggering of star formation. By modeling the foreground gravitational fields, $<10$% of the primary SMGs can be strongly lensed with a magnification $\mu>2$. We determine that about 90\% of the primary SMGs have lines that are better described by double Gaussian profiles, and the median separation of the two Gaussian peaks is 430$\pm$40 km s$^{-1}$. This allows estimates of an average baryon mass, which together with the line dispersion measurements puts our primary SMGs on the similar mass-$\sigma$ correlation found on local early-type galaxies. Finally, the number density of our $z>4$ primary SMGs is found to be $1^{+0.9}_{-0.6}\times10^6$ cMpc$^{-3}$, suggesting that they can be the progenitors of $z\sim3-4$ massive quiescent galaxies., Comment: 30 pages, 16 figures, ApJ in press

Fluorine is one of the most interesting elements for nuclear and stellar astrophysics. Fluorine abundance was first measured for stars other than the Sun in 1992, then for a handful metal-poor stars, which are likely to have formed in the early Universe. The main production sites of fluorine are under debate and include asymptotic giant branch (AGB) stars, $\nu$-process in core-collapse supernovae, and Wolf-Rayet (WR) stars. Due to the difference in the mass and lifetime of progenitor stars, high redshift observations of fluorine can help constrain the mechanism of fluorine production in massive galaxies. Here, we report the detection of HF (S/N = 8) in absorption in a gravitationally lensed dusty star-forming galaxy at redshift z=4.4 with $N_{\rm HF}$/$N_{\rm{H_2}}$ as high as $\sim2\times10^{-9}$, indicating a very quick ramp-up of the chemical enrichment in this high-z galaxy. At z=4.4, AGB stars of a few solar masses are very unlikely to dominate the enrichment. Instead, we show that WR stars are required to produce the observed fluorine abundance at this time, with other production mechanisms becoming important at later times. These observations therefore provide an insight into the underlying processes driving the `ramp-up' phase of chemical enrichment alongside rapid stellar mass assembly in a young massive galaxy., Comment: 21 pages, 4 figures, published in Nature Astronomy

The Nearby Evolved Stars Survey (NESS) is a volume-complete sample of $\sim$850 Galactic evolved stars within 3\,kpc at (sub-)mm wavelengths, observed in the CO $J = $ (2$-$1) and (3$-$2) rotational lines, and the sub-mm continuum, using the James Clark Maxwell Telescope and Atacama Pathfinder Experiment. NESS consists of five tiers, based on distances and dust-production rate (DPR). We define a new metric for estimating the distances to evolved stars and compare its results to \emph{Gaia} EDR3. Replicating other studies, the most-evolved, highly enshrouded objects in the Galactic Plane dominate the dust returned by our sources, and we initially estimate a total DPR of $4.7\times 10^{-5}$ M$_\odot$ yr$^{-1}$ from our sample. Our sub-mm fluxes are systematically higher and spectral indices are typically shallower than dust models typically predict. The 450/850 $\mu$m spectral indices are consistent with the blackbody Rayleigh--Jeans regime, suggesting a large fraction of evolved stars have unexpectedly large envelopes of cold dust., Comment: 20 pages, 13 figures, 5 tables, accepted for publications in MNRAS

High-redshift dusty star-forming galaxies with very high star formation rates (500 -- 3000 M$_{\odot}$ yr$^{-1}$) are key to understanding the formation of the most extreme galaxies in the early Universe. Characterising the gas reservoir of these systems can reveal the driving factor behind the high star formation. Using molecular gas tracers like high-J CO lines, neutral carbon lines and the dust continuum, we can estimate the gas density and radiation field intensity in their interstellar media. In this paper, we present high resolution ($\sim$0.4$^{\prime\prime}$) observations of CO(7-6), [CI](2-1) and dust continuum of 3 lensed galaxies from the SPT-SMG sample at $z\sim$ 3 with the Atacama Large Millimeter/submillimeter Array. Our sources have high intrinsic star-formation rates ($>$850 M$_{\odot}$yr$^{-1}$) and rather short depletion timescales ($<$100 Myr). Based on the L$_{[\rm CI](2-1)}$/L$_{\rm CO(7-6)}$ and L$_{[\rm CI](2-1)}$/L$_{\rm IR}$ ratios, our galaxy sample has similar radiation field intensities and gas densities compared to other submillimetre galaxies. We perform visibility-based lens modelling on these objects to reconstruct the kinematics in the source plane. We find that the cold gas masses of the sources are compatible with simple dynamical mass estimates using ULIRG-like values of the CO-H$_2$ conversion factor $\alpha_{\rm CO}$ but not Milky Way-like values. We find diverse source kinematics in our sample: SPT0103-45 and SPT2147-50 are likely rotating disks while SPT2357-51 is possibly a major merger. The analysis presented in the paper could be extended to a larger sample to determine better statistics of morphologies and interstellar medium properties of high-$z$ dusty star-forming galaxies., Comment: 29 pages, 26 figures, Accepted for publication in A&A. Figure 16 and the related conclusions have been revised

We present a detailed overview of the science goals and predictions for the Prime-Cam direct detection camera/spectrometer being constructed by the CCAT-prime collaboration for dedicated use on the Fred Young Submillimeter Telescope (FYST). The FYST is a wide-field, 6-m aperture submillimeter telescope being built (first light in mid-2024) by an international consortium of institutions led by Cornell University and sited at more than 5600 meters on Cerro Chajnantor in northern Chile. Prime-Cam is one of two instruments planned for FYST and will provide unprecedented spectroscopic and broadband measurement capabilities to address important astrophysical questions ranging from Big Bang cosmology through reionization and the formation of the first galaxies to star formation within our own Milky Way galaxy. Prime-Cam on the FYST will have a mapping speed that is over ten times greater than existing and near-term facilities for high-redshift science and broadband polarimetric imaging at frequencies above 300 GHz. We describe details of the science program enabled by this system and our preliminary survey strategies., Comment: 61 pages, 16 figures. Resubmitted to ApJSS July 11, 2022

In the lithium-ion battery literature, discharges followed by a relaxation to equilibrium are frequently used to validate models and their parametrizations. Good agreement with experiment during discharge is easily attained with a pseudo-two-dimensional model such as the Doyle-Fuller-Newman (DFN) model. The relaxation portion, however, is typically not well-reproduced, with the relaxation in experiments occurring much more slowly than in models. In this study, using a model that includes a size distribution of the active material particles, we give a physical explanation for the slow relaxation phenomenon. This model, the Many-Particle-DFN (MP-DFN), is compared against discharge and relaxation data from the literature, and optimal fits of the size distribution parameters (mean and variance), as well as solid-state diffusivities, are found using numerical optimization. The voltage after relaxation is captured by careful choice of the current cut-off time, allowing a single set of physical parameters to be used for all C-rates, in contrast to previous studies. We find that the MP-DFN can accurately reproduce the slow relaxation, across a range of C-rates, whereas the DFN cannot. Size distributions allow for greater internal heterogeneities, giving a natural origin of slower relaxation timescales that may be relevant in other, as yet explained, battery behavior., Comment: 32 pages, 9 figures, submitted to Journal of the Electrochemical Society (10/03/2021)

We construct a new solar cycle phase clock which maps each of the last 18 solar cycles onto a single normalized epoch for the approximately 22 year Hale (magnetic polarity) cycle, using the Hilbert transform of daily sunspot numbers (SSN) since 1818. The occurrences of solar maxima show almost no Hale cycle dependence, confirming that the clock is synchronized to polarity reversals. The odd cycle minima lead the even cycle minima by ~ 1.1 normalized years, whereas the odd cycle terminators (McIntosh et al. (2019)) lag the even cycle terminators by ~ 2.3 normalized years. The mimimum-terminator interval is thus relatively extended for odd cycles and shortened for even ones. We re-engineer the Sargent(1985,2021) R27 index and combine it with our epoch analysis to obtain a high time resolution parameter for 27 day recurrence in aa, . This reveals that the transition to recurrence, that is, to an ordered solar wind dominated by high speed streams, is fast, occurring within 2-3 solar rotations or less. It resolves an extended late declining phase which is approximately twice as long on even Schwabe cycles as odd. Galactic Cosmic Ray flux rises in step with but then stays high. Our analysis also identifies a slow timescale trend in SSN that simply tracks the Gleissberg cycle. We find that this trend is in phase with the slow timescale trend in the modulus of sunspot latitudes, and in antiphase with that of the R27 index., Comment: 27 pages (manuscript) 12 Figures

Asymptotic homogenisation is used to systematically derive reduced-order macroscopic models of conductive behaviour in spirally-wound layered materials in which the layers have very different conductivities. The problem is motivated by the need for simplified models of the electrical and thermal behaviour of lithium-ion cells, accounting for the highly conductive metallic current collectors and relatively poorly conductive electrodes. We identify and study three distinguished limits, and then describe two composite models which each provide a uniform approximation spanning two distinguished limits. We compare the results of the various reduced-order models with calculations of the full model on a detailed geometry to give a guide to the accuracy of the approximations., Comment: Main article: 24 pages, 8 figures. Supplementary material: 9 pages, 2 figures. Submitted to SIAM Journal on Applied Mathematics on 9 November 2020

We analyse the physical properties of 121 SNR $\geq$ 5 sub-millimetre galaxies (SMGs) from the STUDIES 450-$\mu$m survey. We model their UV-to-radio spectral energy distributions using MAGPHYS+photo-$z$ and compare the results to similar modelling of 850-$\mu$m-selected SMG sample from AS2UDS, to understand the fundamental physical differences between the two populations at the observed depths. The redshift distribution of the 450-$\mu$m sample has a median of $z$ = 1.85 $\pm$ 0.12 and can be described by strong evolution of the far-infrared luminosity function. The fainter 450-$\mu$m sample has $\sim$14 times higher space density than the brighter 850-$\mu$m sample at $z$ $\lesssim$2, and a comparable space density at $z$ = 2-3, before rapidly declining, suggesting LIRGs are the main obscured population at $z$ $\sim$ 1-2, while ULIRGs dominate at higher redshifts. We construct rest-frame $\sim$ 180-$\mu$m-selected and dust-mass-matched samples at $z$ = 1-2 and $z$ = 3-4 from the 450-$\mu$m and 850-$\mu$m samples, respectively, to probe the evolution of a uniform sample of galaxies spanning the cosmic noon era. Using far-infrared luminosity, dust masses and an optically-thick dust model, we suggest that higher-redshift sources have higher dust densities due to inferred dust continuum sizes which are roughly half of those for the lower-redshift population at a given dust mass, leading to higher dust attenuation. We track the evolution in the cosmic dust mass density and suggest that the dust content of galaxies is governed by a combination of both the variation of gas content and dust destruction timescale., Comment: 20 pages, 7 figures, MNRAS accepted

We present APEX-LABOCA 870 micron observations of the fields surrounding the nine brightest, high-redshift, unlensed objects discovered in the South Pole Telescope's (SPT) 2500 square degrees survey. Initially seen as point sources by SPT's 1-arcmin beam, the 19-arcsec resolution of our new data enables us to deblend these objects and search for submillimetre (submm) sources in the surrounding fields. We find a total of 98 sources above a threshold of 3.7 sigma in the observed area of 1300 square arcminutes, where the bright central cores resolve into multiple components. After applying a radial cut to our LABOCA sources to achieve uniform sensitivity and angular size across each of the nine fields, we compute the cumulative and differential number counts and compare them to estimates of the background, finding a significant overdensity of approximately 10 at 14 mJy. The large overdensities of bright submm sources surrounding these fields suggest that they could be candidate protoclusters undergoing massive star-formation events. Photometric and spectroscopic redshifts of the unlensed central objects range from 3 to 7, implying a volume density of star-forming protoclusters of approximately 0.1 per giga-parsec cube. If the surrounding submm sources in these fields are at the same redshifts as the central objects, then the total star-formation rates of these candidate protoclusters reach 10,000 solar masses per year, making them much more active at these redshifts than what has been seen so far in both simulations and observations.

We analyse a robust sample of 30 near-infrared-faint (K>25.3, 5 sigma) submillimetre galaxies selected across a 0.96 deg^2 field, to investigate their properties and the cause of their lack of detectable optical/near-infrared emission. Our analysis exploits precise identifications based on ALMA 870um continuum imaging, combined with the very deep near-infrared imaging from the UKIDSS-UDS survey. We estimate that K>25.3 submillimetre galaxies represent 15+/-2 per cent of the total population brighter than S870=3.6mJy, with an expected surface density of ~450/deg^2 above S870>1mJy. As such they pose a source of contamination in surveys for both high-redshift "quiescent" galaxies and very-high-redshift Lyman-break galaxies. We show that these K-faint submillimetre galaxies are simply the tail of the broader submillimetre population, with comparable dust and stellar masses to K<25.3 mag submillimetre galaxies, but lying at significantly higher redshifts (z=3.44+/-0.06 versus z=2.36+/-0.11) and having higher dust attenuation (Av=5.2+/-0.3 versus Av=2.9+/-0.1). We investigate the origin of the strong dust attenuation and find indications that these K-faint galaxies have smaller dust continuum sizes than the K<25.3 galaxies, as measured by ALMA, which suggests their high attenuation is related to their compact sizes. We find a correlation of dust attenuation with star-formation rate surface density (Sigma_SFR), with the K-faint submillimetre galaxies representing the higher-Sigma_SFR and highest-Av galaxies. The concentrated, intense star-formation activity in these systems is likely to be associated with the formation of spheroids in compact galaxies at high redshifts, but as a result of their high obscuration these are completely missed in UV, optical and even near-infrared surveys., Comment: 9 pages, 4 figures. Submitted to MNRAS, comments welcome

We study the radio properties of 706 sub-millimeter galaxies (SMGs) selected at 870$\mu$m with the Atacama Large Millimeter Array from the SCUBA-2 Cosmology Legacy Survey map of the Ultra Deep Survey field. We detect 273 SMGs at $>4\sigma$ in deep Karl G. Jansky Very Large Array 1.4 GHz observations, of which a subset of 45 SMGs are additionally detected in 610 MHz Giant Metre-Wave Radio Telescope imaging. We quantify the far-infrared/radio correlation through parameter $q_\text{IR}$, defined as the logarithmic ratio of the far-infrared and radio luminosity, and include the radio-undetected SMGs through a stacking analysis. We determine a median $q_\text{IR} = 2.20\pm0.03$ for the full sample, independent of redshift, which places these $z\sim2.5$ dusty star-forming galaxies $0.44\pm0.04$ dex below the local correlation for both normal star-forming galaxies and local ultra-luminous infrared galaxies (ULIRGs). Both the lack of redshift-evolution and the offset from the local correlation are likely the result of the different physical conditions in high-redshift starburst galaxies, compared to local star-forming sources. We explain the offset through a combination of strong magnetic fields ($B\gtrsim0.2$mG), high interstellar medium (ISM) densities and additional radio emission generated by secondary cosmic rays. While local ULIRGs are likely to have similar magnetic field strengths, we find that their compactness, in combination with a higher ISM density compared to SMGs, naturally explains why local and high-redshift dusty star-forming galaxies follow a different far-infrared/radio correlation. Overall, our findings paint SMGs as a homogeneous population of galaxies, as illustrated by their tight and non-evolving far-infrared/radio correlation., Comment: Accepted for publication in ApJ; 18 pages + appendices; 7 figures in main text

We quantify the spatiotemporal evolution of the substorm ionospheric current system utilizing the SuperMAG 100+ magnetometers.We construct dynamical directed networks from this data for the first time. If the canonical cross-correlation between vector magnetic field perturbations observed at two magnetometer stations exceeds a threshold, they form a network connection. The time lag at which canonical cross-correlation is maximal determines the direction of propagation or expansion of the structure captured by the network connection. If spatial correlation reflects ionospheric current patterns, network properties can test different models for the evolving substorm current system.We select 86 isolated substorms based on nightside ground station coverage. We find, and obtain the timings for, a consistent picture in which the classic substorm current wedge forms. A current system is seen premidnight following the substorm current wedge westward expansion. Later, there is a weaker signal of eastward expansion. Finally, there is evidence of substorm-enhanced convection.

We present a survey of the molecular gas in 61 submillimetre galaxies (SMGs) selected from 870$\mu$m continuum surveys of the COSMOS, UDS and ECDFS fields, using the Atacama Large Millimeter Array (ALMA) and the Northern Extended Millimeter Array (NOEMA). 46 $^{12}$CO ($J=$2-5) emission lines are detected in 45 of the targets at $z=$1.2-4.8, with redshifts indicating that those which are submillimetre bright and undetected/faint in the optical/near-infrared typically lie at higher redshifts, with a gradient of $\Delta z/\Delta S_{870}=$0.11$\pm$0.04mJy$^{-1}$. We also supplement our data with literature sources to construct a statistical CO spectral line energy distribution and find the $^{12}$CO line luminosities in SMGs peak at $J_{\rm up}\sim$6, consistent with the Cosmic Eyelash, among similar studies. Our SMGs lie mostly on or just above the main sequence, displaying a decrease in their gas depletion timescales $t_{\rm dep} = M_{\rm gas}/{\rm SFR}$ with redshift in the range $z\sim$1-5 and a median of 200$\pm$50Myr at $z\sim$2.8. This coincides with an increase in molecular gas fraction $\mu_{\rm gas} = M_{\rm gas}/M_\ast$ across the same redshift range. Finally we demonstrate that the $M_{\rm baryon}$-$\sigma$ distribution of our SMGs is consistent with that followed by early-type galaxies in the Coma cluster, providing strong support to the suggestion that SMGs are progenitors of massive local spheroidal galaxies. On the basis of this we suggest that the SMG populations above and below an 870-$\mu$m flux limit of $S_{870}\sim$5mJy may correspond to the division between slow- and fast-rotators seen in local early-type galaxies., Comment: Submitted to MNRAS

The study of nonlinear waves that collapse in finite time is a theme of universal interest, e.g. within optical, atomic, plasma physics, and nonlinear dynamics. Here we revisit the quintessential example of the nonlinear Schrodinger equation and systematically derive a normal form for the emergence of blowup solutions from stationary ones. While this is an extensively studied problem, such a normal form, based on the methodology of asymptotics beyond all algebraic orders, unifies both the dimension-dependent and power-law-dependent bifurcations previously studied; it yields excellent agreement with numerics in both leading and higher-order effects; it is applicable to both infinite and finite domains; and it is valid in all (subcritical, critical and supercritical) regimes.

For many practical applications, fully coupled three-dimensional models describing the behaviour of lithium-ion pouch cells are too computationally expensive. However, owing to the small aspect ratio of typical pouch cell designs, such models are well approximated by splitting the problem into a model for through-cell behaviour and a model for the transverse behaviour. In this paper, we combine different simplifications to through-cell and transverse models to develop a hierarchy of reduced-order pouch cell models. We give a critical numerical comparison of each of these models in both isothermal and thermal settings, and also study their performance on realistic drive cycle data. Finally, we make recommendations regarding model selection, taking into account the available computational resource and the quantities of interest in a particular study.

We present Gemini-S and {\it Spitzer}-IRAC optical-through-near-IR observations in the field of the SPT2349-56 proto-cluster at $z=4.3$. We detect optical/IR counterparts for only nine of the 14 submillimetre galaxies (SMGs) previously identified by ALMA in the core of SPT2349-56. In addition, we detect four $z\sim4$ Lyman-break galaxies (LBGs) in the 30 arcsec diameter region surrounding this proto-cluster core. Three of the four LBGs are new systems, while one appears to be a counterpart of one of the nine observed SMGs. We identify a candidate brightest cluster galaxy (BCG) with a stellar mass of $(3.2^{+2.5}_{-1.4})\times10^{11}\,{\rm M}_{\odot}$. The stellar masses of the eight other SMGs place them on, above, and below the main sequence of star formation at $z\approx4.5$. The cumulative stellar mass for the SPT2349-56 core is at least $(11.5\pm2.9)\times10^{11}\,{\rm M}_{\odot}$, a sizeable fraction of the stellar mass in local BCGs, and close to the universal baryon fraction (0.16) relative to the virial mass of the core ($10^{13}\,{\rm M}_{\odot}$). As all 14 of these SMGs are destined to quickly merge, we conclude that the proto-cluster core has already developed a significant stellar mass at this early stage, comparable to $z=1$ BCGs. Importantly, we also find that the SPT2349-56 core structure would be difficult to uncover in optical surveys, with none of the ALMA sources being easily identifiable or constrained through $g,r,$ and $i$ colour-selection in deep optical surveys and only a modest overdensity of LBGs over the extended core structure. SPT2349-56 therefore represents a truly dust-obscured phase of a massive cluster core under formation.

The South Pole Telescope (SPT) has systematically identified 81 high-redshift, strongly gravitationally lensed, dusty star-forming galaxies (DSFGs) in a 2500 square degree cosmological mm-wave survey. We present the final spectroscopic redshift survey of this flux-limited ($S_{870\, \mathrm{\mu m}} > 25\, \mathrm{mJy}$) sample, initially selected at $1.4$ mm. The redshift survey was conducted with the Atacama Large Millimeter/submillimeter Array across the $3$ mm spectral window, targeting carbon monoxide line emission. By combining these measurements with ancillary data, the SPT sample is now spectroscopically complete, with redshifts spanning $1.9$$<$$z$$<$$6.9$ and a median of $z=3.9 \pm 0.2$. We present the mm through far-infrared photometry and spectral energy density fits for all sources, along with their inferred intrinsic properties. Comparing the properties of the SPT sources to the unlensed DSFG population, we demonstrate that the SPT-selected DSFGs represent the most extreme infrared-luminous galaxies, even after accounting for strong gravitational lensing. The SPT sources have a median star formation rate of $2.3(2)\times 10^3\, \mathrm{M_\odot yr^{-1}}$ and a median dust mass of $1.4(1)\times10^9\, \mathrm{M_\odot}$. However, the inferred gas depletion timescales of the SPT sources are comparable to those of unlensed DSFGs, once redshift is taken into account. This SPT sample contains roughly half of the known spectroscopically confirmed DSFGs at $z$$>$$5$, making this the largest sample of high-redshift DSFGs to-date, and enabling the "high-redshift tail" of extremely luminous DSFGs to be measured. Though galaxy formation models struggle to account for the SPT redshift distribution, the larger sample statistics from this complete and well-defined survey will help inform future theoretical efforts., Comment: 56 pages, 25 figures, accepted for publication in ApJ

In mathematical models of lithium-ion batteries, the highly heterogeneous porous electrodes are frequently approximated as comprising spherical particles of uniform size, leading to the commonly-used single-particle model (SPM) when transport in the electrolyte is assumed to be fast. Here electrode heterogeneity is modelled by extending this to a distribution of particle sizes. Unimodal and bimodal particle-size distributions (PSD) are considered. For a unimodal PSD, the effect of the spread of the distribution on the cell dynamics is investigated, and choice of effective particle radius when approximating by an SPM assessed. Asymptotic techniques are used to derive a correction to the SPM valid for narrow, but realistic, PSDs. In addition, it is shown that the heterogeneous internal states of all particles (relevant when modelling degradation, for example) can be efficiently computed after-the-fact. For a bimodal PSD, the results are well approximated by a double-particle model (DPM), with one size representing each mode. Results for lithium iron phosphate with a bimodal PSD show that the DPM captures an experimentally-observed double-plateau in the discharge curve, suggesting it is entirely due to bimodality., Comment: 32 pages, submitted to SIAM Journal on Applied Mathematics 04/06/2020

We report a measurement of the E-mode polarization power spectrum of the cosmic microwave background (CMB) using 150 GHz data taken from July 2014 to December 2016 with the POLARBEAR experiment. We reach an effective polarization map noise level of $32\,\mu\mathrm{K}$-$\mathrm{arcmin}$ across an observation area of 670 square degrees. We measure the EE power spectrum over the angular multipole range $500 \leq \ell <3000$, tracing the third to seventh acoustic peaks with high sensitivity. The statistical uncertainty on E-mode bandpowers is $\sim 2.3 \mu {\rm K}^2$ at $\ell \sim 1000$ with a systematic uncertainty of 0.5$\mu {\rm K}^2$. The data are consistent with the standard $\Lambda$CDM cosmological model with a probability-to-exceed of 0.38. We combine recent CMB E-mode measurements and make inferences about cosmological parameters in $\Lambda$CDM as well as in extensions to $\Lambda$CDM. Adding the ground-based CMB polarization measurements to the Planck dataset reduces the uncertainty on the Hubble constant by a factor of 1.2 to $H_0 = 67.20 \pm 0.57 {\rm km\,s^{-1} \,Mpc^{-1}}$. When allowing the number of relativistic species ($N_{eff}$) to vary, we find $N_{eff} = 2.94 \pm 0.16$, which is in good agreement with the standard value of 3.046. Instead allowing the primordial helium abundance ($Y_{He}$) to vary, the data favor $Y_{He} = 0.248 \pm 0.012$. This is very close to the expectation of 0.2467 from Big Bang Nucleosynthesis. When varying both $Y_{He}$ and $N_{eff}$, we find $N_{eff} = 2.70 \pm 0.26$ and $Y_{He} = 0.262 \pm 0.015$., Comment: 15 pages, 5 figures, submitted to ApJ

A three-dimensional model of a single-layer lithium-ion pouch cell is presented which couples conventional porous electrode theory describing cell electrochemical behaviour with an energy balance describing cell thermal behaviour. Asymptotic analysis of the model is carried out by exploiting the small aspect ratio typical of pouch cell designs. The analysis reveals the scaling that results in a distinguished limit, and highlights the role played by the electrical conductivities of the current collectors. The resulting model comprises a collection of one-dimensional models for the through-cell electrochemical behaviour which are coupled via two-dimensional problems for the Ohmic and thermal behaviour in the planar current collectors. A further limit is identified which reduces the problem to a single volume-averaged through-cell model, greatly reducing the computational complexity. Numerical simulations are presented which illustrate and validate the asymptotic results., Comment: 27 pages, 6 figures, submitted to SIAM Journal on Applied Mathematics (08/05/2020)

We present an overview and description of the eMERLIN Galaxy Evolution survey (eMERGE) Data Release 1 (DR1), a large program of high-resolution 1.5 GHz radio observations of the GOODS-N field comprising $\sim140$ hours of observations with eMERLIN and $\sim40$ hours with the Very Large Array (VLA). We combine the long baselines of eMERLIN (providing high angular resolution) with the relatively closely-packed antennas of the VLA (providing excellent surface brightness sensitivity) to produce a deep 1.5 GHz radio survey with the sensitivity ($\sim 1.5\mu$Jy beam$^{-1}$), angular resolution ($0.2"$--$0.7"$) and field-of-view ($\sim15' \times 15'$) to detect and spatially resolve star-forming galaxies and AGN at $z\gtrsim 1$. The goal of eMERGE is to provide new constraints on the deep, sub-arcsecond radio sky which will be surveyed by SKA1-mid. In this initial publication, we discuss our data analysis techniques, including steps taken to model in-beam source variability over a $\sim20$ year baseline and the development of new point spread function/primary beam models to seamlessly merge eMERLIN and VLA data in the $uv$ plane. We present early science results, including measurements of the luminosities and/or linear sizes of $\sim500$ galaxes selected at 1.5 GHz. In combination with deep Hubble Space Telescope observations, we measure a mean radio-to-optical size ratio of $r_{\rm eMERGE}/r_{\rm HST}\sim1.02\pm0.03$, suggesting that in most high-redshift galaxies, the $\sim$GHz continuum emission traces the stellar light seen in optical imaging. This is the first in a series of papers which will explore the $\sim$kpc-scale radio properties of star-forming galaxies and AGN in the GOODS-N field observed by eMERGE DR1., Comment: 21 pages, 12 colour figures, 3 tables -- accepted for publication in MNRAS

Detection of wheat heads is an important task allowing to estimate pertinent traits including head population density and head characteristics such as sanitary state, size, maturity stage and the presence of awns. Several studies developed methods for wheat head detection from high-resolution RGB imagery. They are based on computer vision and machine learning and are generally calibrated and validated on limited datasets. However, variability in observational conditions, genotypic differences, development stages, head orientation represents a challenge in computer vision. Further, possible blurring due to motion or wind and overlap between heads for dense populations make this task even more complex. Through a joint international collaborative effort, we have built a large, diverse and well-labelled dataset, the Global Wheat Head detection (GWHD) dataset. It contains 4,700 high-resolution RGB images and 190,000 labelled wheat heads collected from several countries around the world at different growth stages with a wide range of genotypes. Guidelines for image acquisition, associating minimum metadata to respect FAIR principles and consistent head labelling methods are proposed when developing new head detection datasets. The GWHD is publicly available at http://www.global-wheat.com/ and aimed at developing and benchmarking methods for wheat head detection., Comment: 16 pages, 7 figures, Dataset paper

We present an ALMA study of the ~180 brightest sources in the SCUBA-2 map of the COSMOS field from the S2COSMOS survey, as a pilot study for AS2COSMOS - a full survey of the ~1,000 sources in this field. In this pilot we have obtained 870-um continuum maps of an essentially complete sample of the brightest 182 sub-millimetre sources (S_850um=6.2mJy) in COSMOS. Our ALMA maps detect 260 sub-millimetre galaxies (SMGs) spanning a range in flux density of S_870um=0.7-19.2mJy. We detect more than one SMG counterpart in 34+/-2 per cent of sub-millimetre sources, increasing to 53+/-8 per cent for SCUBA-2 sources brighter than S_850um>12mJy. We estimate that approximately one-third of these SMG-SMG pairs are physically associated (with a higher rate for the brighter secondary SMGs, S_870um>3mJy), and illustrate this with the serendipitous detection of bright [CII] 157.74um line emission in two SMGs, AS2COS0001.1 & 0001.2 at z=4.63, associated with the highest significance single-dish source. Using our source catalogue we construct the interferometric 870um number counts at S_870um>6.2mJy. We use the extensive archival data of this field to construct the multiwavelength spectral energy distribution of each AS2COSMOS SMG, and subsequently model this emission with MAGPHYS to estimate their photometric redshifts. We find a median photometric redshift for the S_870um>6.2mJy AS2COSMOS sample of z=2.87+/-0.08, and clear evidence for an increase in the median redshift with 870-um flux density suggesting strong evolution in the bright-end of the 870um luminosity function., Comment: Submitted to MNRAS, comments welcome. Figures 1, 4, A1 degraded to comply with size limits

We present a catalog of emissive point sources detected in the SPT-SZ survey, a contiguous 2530-square-degree area surveyed with the South Pole Telescope (SPT) from 2008 - 2011 in three bands centered at 95, 150, and 220 GHz. The catalog contains 4845 sources measured at a significance of 4.5 sigma or greater in at least one band, corresponding to detections above approximately 9.8, 5.8, and 20.4 mJy in 95, 150, and 220 GHz, respectively. Spectral behavior in the SPT bands is used for source classification into two populations based on the underlying physical mechanisms of compact, emissive sources that are bright at millimeter wavelengths: synchrotron radiation from active galactic nuclei and thermal emission from dust. The latter population includes a component of high-redshift sources often referred to as submillimeter galaxies (SMGs). In the relatively bright flux ranges probed by the survey, these sources are expected to be magnified by strong gravitational lensing. The survey also contains sources consistent with protoclusters, groups of dusty galaxies at high redshift undergoing collapse. We cross-match the SPT-SZ catalog with external catalogs at radio, infrared, and X-ray wavelengths and identify available redshift information. The catalog splits into 3980 synchrotron-dominated and 865 dust-dominated sources and we determine a list of 506 SMGs. Ten sources in the catalog are identified as stars. We calculate number counts for the full catalog, and synchrotron and dusty components, using a bootstrap method and compare our measured counts with models. This paper represents the third and final catalog of point sources in the SPT-SZ survey., Comment: 43 pages, 19 figures, 7 tables. Submitted to AAS Journals 03/05/2020. 03/23/2020 co-author affiliation and acknowledgments updated

SuperSpec is an on-chip filter-bank spectrometer designed for wideband moderate-resolution spectroscopy at millimeter wavelengths, employing TiN kinetic inductance detectors. SuperSpec technology will enable large-format spectroscopic integral field units suitable for high-redshift line intensity mapping and multi-object spectrographs. In previous results we have demonstrated noise performance in individual detectors suitable for photon noise limited ground-based observations at excellent mm-wave sites. In these proceedings we present the noise performance of a full $R\sim 275$ spectrometer measured using deployment-ready RF hardware and software. We report typical noise equivalent powers through the full device of $\sim 3 \times 10^{-16} \ \mathrm{W}/\sqrt{\mathrm{Hz}}$ at expected sky loadings, which are photon noise dominated. Based on these results, we plan to deploy a six-spectrometer demonstration instrument to the Large Millimeter Telescope in early 2020., Comment: 8 pages, 5 figures. Accepted by the Journal of Low Temperature Physics (Proceedings of the 18th International Workshop on Low Temperature Detectors)

Using data from ALMA and near-infrared (NIR) integral field spectrographs including both SINFONI and KMOS on the VLT, we investigate the two-dimensional distributions of H$\alpha$ and rest-frame far-infrared (FIR) continuum in six submillimeter galaxies at $z\sim2$. At a similar spatial resolution ($\sim$0.5" FWHM; $\sim$4.5 kpc at $z=2$), we find that the half-light radius of H$\alpha$ is significantly larger than that of the FIR continuum in half of the sample, and on average H$\alpha$ is a median factor of $2.0\pm0.4$ larger. Having explored various ways to correct for the attenuation, we find that the attenuation-corrected H$\alpha$-based SFRs are systematically lower than the IR-based SFRs by at least a median factor of $3\pm1$, which cannot be explained by the difference in half-light radius alone. In addition, we find that in 40% of cases the total $V$-band attenuation ($A_V$) derived from energy balance modeling of the full ultraviolet(UV)-to-FIR spectral energy distributions (SEDs) is significantly higher than that derived from SED modeling using only the UV-to-NIR part of the SEDs, and the discrepancy appears to increase with increasing total infrared luminosity. Finally, considering all our findings along with the studies in the literature, we postulate that the dust distributions in SMGs, and possibly also in less IR luminous $z\sim2$ massive star-forming galaxies, can be decomposed into three main components; the diffuse dust heated by older stellar populations, the more obscured and extended young star-forming HII regions, and the heavily obscured central regions that have a low filling factor but dominate the infrared luminosity in which the majority of attenuation cannot be probed via UV-to-NIR emissions., Comment: 15 pages, 8 figures, A&A in press