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We discuss ASASSN-24fw, a 13th-magnitude star that optically faded by $\Delta g=4.12\pm 0.02$mag starting in September 2024 after over a decade of quiescence in ASAS-SN. The dimmimg lasted $$8 months before returning to quiescence in late May 2025. The spectral energy distribution (SED) before the event is that of a pre-main sequence or a modestly evolved F star with some warm dust emission. The shape of the optical SED during the dim phase is unchanged and the optical and near-infrared spectra are those of an F star. The SED and the dilution of some of the F star infrared absorption features near minimum suggest the presence of a $$ $0.25$M_$$ M dwarf binary companion. The 43.8 year period proposed by Nair & Denisenko (2024) appears correct and is probably half the precession period of a circumbinary disk. The optical eclipse is nearly achromatic, although slightly deeper in bluer filters, $\Delta (g-z)=0.31\pm 0.15$mag, and the $V$band emission is polarized by up to 4%. The materials most able to produce such small optical color changes and a high polarization are big ($$20 $\mu$m) carbonaceous or water ice grains. Particle distributions dominated by big grains are seen in protoplanetary disks, Saturn-like ring systems and evolved debris disks. We also carry out a survey of occultation events, finding 46 additional systems, of which only 7 (4) closely match $\epsilon$Aurigae (KH 15D), the two archetypes of stars with long and deep eclipses. The full sample is widely distributed in an optical color-magnitude diagram, but roughly half show a mid-IR excess. It is likely many of the others have cooler dust since it seems essential to produce the events. 

Abstract IceCube is a Cherenkov detector instrumenting over a cubic kilometer of glacial ice deep under the surface of the South Pole. The DeepCore sub-detector lowers the detection energy threshold to a few GeV, enabling the precise measurements of neutrino oscillation parameters with atmospheric neutrinos. The reconstruction of neutrino interactions inside the detector is essential in studying neutrino oscillations. It is particularly challenging to reconstruct sub-100 GeV events with the IceCube detectors due to the relatively sparse detection units and detection medium. Convolutional neural networks (CNNs) are broadly used in physics experiments for both classification and regression purposes. This paper discusses the CNNs developed and employed for the latest IceCube-DeepCore oscillation measurements [1]. These CNNs estimate various properties of the detected neutrinos, such as their energy, direction of arrival, interaction vertex position, flavor-related signature, and are also used for background classification. 

Abstract The powerful jets of blazars have been historically considered as likely sites of high-energy cosmic-ray acceleration. However, the particulars of the launched jet and the locations of leptonic and hadronic jet loading remain unclear. In the case when leptonic and hadronic particle injection occur jointly, a temporal correlation between synchrotron radiation and neutrino production is expected. We use a first catalog of millimeter wavelength (95–225 GHz) blazar light curves from the Atacama Cosmology Telescope for a time-dependent correlation with 12 yr of muon neutrino events from the IceCube South Pole Neutrino Observatory. Such millimeter emission traces activity of the bright jet base, which is often self-absorbed at lower frequencies and potentially gamma-ray opaque. We perform an analysis of the population, as well as analyses of individual, selected sources. We do not observe a significant signal from the stacked population. TXS 0506+056 is found as the most significant, individual source, though this detection is not globally significant in our analysis of selected active galactic nuclei. Our results suggest that the majority of millimeter-bright blazars are neutrino dim. In general, it is possible that many blazars have lighter, leptonic jets, or that only selected blazars provide exceptional conditions for neutrino production. 

Abstract In the IceCube Neutrino Observatory, a signal of astrophysical neutrinos is obscured by backgrounds from atmospheric neutrinos and muons produced in cosmic-ray interactions. IceCube event selections used to isolate the astrophysical neutrino signal often focus on the morphology of the light patterns recorded by the detector. The analyses presented here use the new IceCube Enhanced Starting Track Event Selection (ESTES), which identifies events likely generated by muon–neutrino interactions within the detector geometry, focusing on neutrino energies of 1–500 TeV with a median angular resolution of 1.4 $\stackrel{\text{°}}{}$. Selecting for starting-track events filters out not only the atmospheric-muon background but also the atmospheric-neutrino background in the southern sky. This improves IceCube’s muon–neutrino sensitivity to southern-sky neutrino sources, especially for Galactic sources that are not expected to produce a substantial flux of neutrinos above 100 TeV. In this work, the ESTES sample was applied for the first time to search for astrophysical sources of neutrinos, including a search for diffuse neutrino emission from the Galactic plane. No significant excesses were identified from any of the analyses; however, constraining limits are set on the hadronic emission from TeV gamma-ray Galactic plane objects and models of the diffuse Galactic plane neutrino flux. 

Ascomycota, the most speciose phylum of fungi, is a complex entity, comprising three diversesubphyla: Pezizomycotina, Saccharomycotina, and Taphrinomycotina. The largest and most diversesubphylum, Pezizomycotina, is a rich tapestry of 16 classes and 171 orders. Saccharomycotina, thesecond largest subphylum, is a diverse collection of seven classes and 12 orders, whileTaphrinomycotina, the smallest, is a unique assembly of six classes and six orders. Over the pastdecade, numerous taxonomic studies have focused on the generic, family, and class classifications ofAscomycota. These efforts, well-documented across various databases, are crucial for acomprehensive understanding of the classification. However, the study of taxonomy at the ordinallevel, a crucial tier in the taxonomic hierarchy, has been largely overlooked. In a global collaborationwith mycologists and lichenologists, this study presents the first comprehensive information on theorders within Pezizomycotina and Taphrinomycotina. The recent taxonomic classification ofSaccharomycotina has led to the exclusion of this subphylum from the present study, as an immediaterevision is not necessary. Each order is thoroughly discussed, highlighting its historical significance,current status, key identification characteristics, evolutionary relationships, ecological and economicroles, future recommendations, and updated family-level classification. Teaching diagrams for thelife cycles of several orders, viz. Asterinales, Helotiales, Hypocreales, Laboulbeniales, Meliolales,Mycosphaerellales, Ophiostomatales, Pezizales, Pleosporales, Phyllachorales, Rhytismatales,Sordariales, Venturiales, Xylariales (Pezizomycotina) and Pneumocystidales,Schizosaccharomycetales and Taphrinales (Taphrinomycotina) are provided. Each diagram is explained with a representative genus/genera of their sexual and asexual cycles of each order. WithinPezizomycotina, Dothideomycetes contains the highest number of orders, with 57, followed bySordariomycetes (52 orders), Lecanoromycetes (21 orders), Eurotiomycetes and Leotiomycetes (12orders each), Laboulbeniomycetes (3 orders), and Arthoniomycetes and Xylonomycetes (2 orderseach). Candelariomycetes, Coniocybomycetes, Geoglossomycetes, Lichinomycetes, Orbiliomycetes,Pezizomycetes, Sareomycetes, and Xylobotryomycetes each contain a single order, whileThelocarpales and Vezdaeales are treated as incertae sedis within Pezizomycotina. Notably, theclasses Candelariomycetes, Coniocybomycetes, Geoglossomycetes, Sareomycetes, andXylonomycetes, all recently grouped under Lichinomycetes, are treated as separate classes based onphylogenetic analysis and current literature. Within Lecanoromycetes, the synonymization ofSporastatiales with Rhizocarpales and Sarrameanales with Schaereriales is not supported in thephylogenetic analysis. These orders are retained separately, and the justifications are provided undereach section as well as in the discussion. Within Leotiomycetes, the order Medeolariales, which wasonce considered part of Helotiales, is treated as a distinct order based on phylogenetic evidence. Theclassification of Medeolariales may change as more data becomes available from different generegions. Lahmiales (Leotiomycetes) is not included in the phylogenetic analysis due to a lack ofmolecular data. Sareomycetes and Xylonomycetes are treated as separate classes. Spathulosporamixed with Lulworthiales and the inclusion of Spathulosporales within Lulworthiomycetidae issupported and extant molecular sampling is important to resolve the phylogenetic boundaries ofmembers of this subclass. The majority of the classes of Pezizomycotina and Taphrinomycotinaformed monophyletic clades in the phylogenetic analysis conducted based on SSU, LSU, 5.8S, TEFand RPB2 sequence data. However, Arthoniomycetes nested with the basal lineage ofDothideomycetes and formed a monophyletic clade also known as the superclass, Dothideomyceta.In Taphrinomycotina, a single order is accepted within each class. 

Abstract The IceCube Neutrino Observatory, instrumenting about 1 km³of deep, glacial ice at the geographic South Pole, is due to be enhanced with the IceCube Upgrade. The IceCube Upgrade, to be deployed during the 2025/26 Antarctic summer season, will consist of seven new strings of photosensors, densely embedded near the bottom center of the existing array. Aside from a world-leading sensitivity to neutrino oscillations, a primary goal is the improvement of the calibration of the optical properties of the instrumented ice. This calibration will be applied to the entire archive of IceCube data, improving the angular and energy resolution of the detected neutrino events. For this purpose, the Upgrade strings include a host of new calibration devices. Aside from dedicated calibration modules, several thousand LED flashers have been incorporated into the photosensor modules. We describe the design, production, and testing of these LED flashers before their integration into the sensor modules as well as the use of the LED flashers during lab testing of assembled sensor modules.