https://astro.theoj.org/ The Open Journal of Astrophysics is an arXiv overlay journal providing open access to peer-reviewed research in astrophysics and cosmology. en Fri, 24 Jul 2026 08:43:00 +0000 This paper challenges the failed-supernova theory for the fading of the yellow supergiant event M31-2014-DS1, suggesting it requires unlikely parameters and supports an alternative scenario involving violent binary interaction. https://doi.org/10.33232/001c.165498 https://astro.theoj.org/article/165498-the-failed-failed-supernova-scenario-of-m31-2014-ds1 Fri, 24 Jul 2026 08:25:00 +0000 The study presents a framework using artificial neural networks and neutron monitors to reconstruct cosmic-ray energy spectra, providing data even in the absence of direct satellite observations. https://doi.org/10.33232/001c.165496 https://astro.theoj.org/article/165496-gcr-spectra-reconstructed-with-neutron-monitor-yield-function-and-artificial-neural-networks-comparison-of-two-methods Fri, 24 Jul 2026 08:11:00 +0000 This article introduces "Exo Skryer", a new, efficient framework for exoplanet and brown dwarf atmospheric research, capable of handling large data sets and complex models. https://doi.org/10.33232/001c.165495 https://astro.theoj.org/article/165495-exo-skryer-a-jax-accelerated-sub-stellar-atmospheric-retrieval-framework Thu, 23 Jul 2026 07:24:00 +0000 An investigation of the performance and calibration challenges of phased-array radio interferometers, using the Irish LOFAR station as a case study, highlighting the importance of accurate beam modelling, etc. https://doi.org/10.33232/001c.165435 https://astro.theoj.org/article/165435-characterising-the-response-of-an-international-lofar-station Thu, 23 Jul 2026 07:15:00 +0000 A time-dependent model of accretion disks around black holes, explaining late-time emission in tidal disruption events and luminous fast blue optical transients and future detectability of such events https://doi.org/10.33232/001c.165434 https://astro.theoj.org/article/165434-viscously-spreading-accretion-disks-around-black-holes-implications-for-tdes-lfbots-and-other-transients Thu, 23 Jul 2026 07:01:00 +0000 JWST observations and ALMA Band 3 data reveal that 50-88% of CO gas in a star-forming filament is locked in ice; corrections are needed for mass measurements in such systems https://doi.org/10.33232/001c.165431 https://astro.theoj.org/article/165431-mapping-co-ice-in-a-star-forming-filament-in-the-3-kpc-arm-with-jwst Tue, 21 Jul 2026 07:44:00 +0000 Deep observations of four UV-bright, gravitationally lensed galaxies, revealing an ionized outflow in one and highlighting the diagnostic power of [O III]88 μm in studying galaxies in the early Universe. https://doi.org/10.33232/001c.165333 https://astro.theoj.org/article/165333-a-first-systematic-study-of-oiii-88-m-at-z-8-two-luminous-oxygen-lines-and-a-powerful-ionized-outflow-in-the-first-600-million-years Tue, 21 Jul 2026 07:33:00 +0000 The study uses a modified HEXTOR energy balance model to predict climate states of terrestrial planets orbiting low-mass stars, suggesting partial to complete ice cover for TRAPPIST-1 e and f. https://doi.org/10.33232/001c.165290 https://astro.theoj.org/article/165290-exploring-trappist-1-climate-states-with-an-energy-balance-model Tue, 21 Jul 2026 06:48:00 +0000 This study presents measurements of the South Pole Telescope's polarized beam response, indicating minimal sidelobe depolarization. The findings suggest potential explanations for frequency-dependent residuals in power spectrum analysis. https://doi.org/10.33232/001c.165326 https://astro.theoj.org/article/165326-characterization-of-the-polarization-beam-response-of-spt-3g-using-point-sources Fri, 17 Jul 2026 07:35:00 +0000 This study proposes using quadratic estimators to test the weak equivalence principle on cosmological scales, offering a practical alternative to the conventional bispectrum approach. https://doi.org/10.33232/001c.165214 https://astro.theoj.org/article/165214-density-reconstruction-from-biased-tracers-testing-the-equivalence-principle-through-consistency-relations