UWC Astrophysics

Physics-informed neural networks have emerged as a coherent framework for building predictive models that combine statistical patterns with domain knowledge. The underlying notion is to enrich the optimization loss function with known relationships to constrain the space of possible solutions. Hydrodynamic simulations are a core constituent of modern cosmology, while the required computations are both …

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Mid-infrared observations are powerful in identifying heavily obscured Active Galactic Nuclei (AGN) which have weak emission in other wavelengths. The Mid-Infrared Instrument (MIRI) onboard JWST offers an excellent chance to perform such studies. We take advantage of the MIRI imaging data from the Cosmic Evolution Early Release Science Survey (CEERS) to investigate the AGN population …

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Semi-numerical simulations are the leading candidates for evolving reionization on cosmological scales. These semi-numerical models are efficient in generating large-scale maps of the 21cm signal, but they are too slow to enable inference at the field level. We present different strategies to train a U-Net to accelerate these simulations. We derive the ionization field directly …

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By combining high-sensitivity LOFAR 150 MHz, uGMRT 400 MHz, GMRT 610 MHz, and JVLA 5 GHz data in the ELAIS-N1 field, we study the radio spectral properties of radio-detected star-forming galaxies (SFGs) at observer-frame frequencies of 150-5000 MHz. We select ~ 3,500 SFGs that have both LOFAR 150 MHz and GMRT 610 MHz detections by …

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We build a bijective mapping between different physical fields from hydrodynamic CAMELS simulations. We train a CycleGAN on three different setups: translating dark matter to neutral hydrogen (Mcdm-HI), mapping between dark matter and magnetic fields magnitude (Mcdm-B), and finally predicting magnetic fields magnitude from neutral hydrogen (HI-B). We assess the performance of the models using …

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The transformation and evolution of a galaxy is strongly influenced by interactions with its environment. Neutral hydrogen (HI) is an excellent way to trace these interactions. Here, we present HI observations of the spiral galaxy NGC~895, which was previously thought to be isolated. High-sensitivity HI observations from the MeerKAT large survey project MIGHTEE reveal possible …

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Context: To study the effects of environment on galaxies we use HI observations of galaxies in and around the cluster A2626. The cluster can effectively be divided in three different environments: the cluster itself, a group environment in the periphery of the cluster (we call it the Swarm) and substructure in the cluster itself. We …

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We study the nature of the faint radio source population detected in the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) Early Science data in the COSMOS field, focusing on the properties of the radio-loud active galactic nuclei (AGN). Using the extensive multi-wavelength data available in the field, we are able to classify 88 per cent …

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The Hydrogen Intensity and Real-time Analysis eXperiment (HIRAX) aims to improve constraints on the dark energy equation of state through measurements of large-scale structure at high redshift (0.8<z<2.5), while serving as a state-of-the-art fast radio burst detector. Bright galactic foregrounds contaminate the 400–800~MHz HIRAX frequency band, so meeting the science goals will require precise instrument …

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We present measurements of the rest-frame ultraviolet luminosity function (UV LF) at redshifts z=3, z=4 and z=5, using 96894, 38655 and 7571 sources respectively to map the transition between AGN and galaxy-dominated ultraviolet emission shortly after the epoch of reionization. Sources are selected using a comprehensive photometric redshift approach, using 10\ds\, of deep extragalactic legacy fields covered by both HSC …

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