bluuebunny/crossref_metadata_2025_split huggingface dataset:
Planting a Lyman alpha forest on AbacusSummit
Authors: Hadzhiyska Boryana , Font-Ribera A , Cuceu A , Chabanier S , Aguilar J , Brooks D , de la Macorra A , Doel P , Eisenstein D J , Forero-Romero J E , Gontcho A Gontcho S , Honscheid K , Kehoe R , Landriau M , Miquel R , Nie Jundan , Percival W J , Rossi G , Tarlé Gregory , Zhou Zhimin 
Published: June 2023

ABSTRACT
The full-shape correlations of the Lyman alpha (Ly α) forest contain a wealth of cosmological information through the Alcock–Paczyński effect. However, these measurements are challenging to model without robustly testing and verifying the theoretical framework used for analysing them. Here, we leverage the accuracy and volume of the N-body simulation suite AbacusSummit to generate high-resolution Ly α skewers and quasi-stellar object (QSO) catalogues. One of the main goals of our mocks is to aid in the full-shape Ly α analysis planned by the Dark Energy Spectroscopic Instrument (DESI) team. We provide optical depth skewers for six of the fiducial cosmology base-resolution simulations ($L_{\rm box} = 2\, h^{-1}\, {\rm Gpc}$, N = 69123) at z = 2.5. We adopt a simple recipe based on the Fluctuating Gunn–Peterson Approximation (FGPA) for constructing these skewers from the matter density in an N-body simulation and calibrate it against the 1D and 3D Ly α power spectra extracted from the hydrodynamical simulation IllustrisTNG (TNG; $L_{\rm box} = 205\, h^{-1}\, {\rm Mpc}$, N = 25003). As an important application, we study the non-linear broadening of the baryon acoustic oscillation (BAO) peak and show the cross-correlation between DESI-like QSOs and our Ly α forest skewers. We find differences on small scales between the Kaiser approximation prediction and our mock measurements of the Ly α × QSO cross-correlation, which would be important to account for in upcoming analyses. The AbacusSummit Ly α forest mocks open up the possibility for improved modelling of cross-correlations between Ly α and cosmic microwave background (CMB) lensing and Ly α and QSOs, and for forecasts of the 3-point Ly α correlation function. Our catalogues and skewers are publicly available on Globus via the National Energy Research Scientific Computing Center (NERSC) (full link under the section ‘Data Availability’).
Electron-scale current sheets and energy dissipation in 3D kinetic-scale plasma turbulence with low electron beta
Authors: Vega Cristian , Roytershteyn Vadim , Delzanno Gian Luca , Boldyrev Stanislav 
Published: June 2023

ABSTRACT
Three-dimensional kinetic-scale turbulence is studied numerically in the regime where electrons are strongly magnetized (the ratio of plasma species pressure to magnetic pressure is βe = 0.1 for electrons and βi = 1 for ions). Such a regime is relevant in the vicinity of the solar corona, the Earth’s magnetosheath, and other astrophysical systems. The simulations, performed using the fluid-kinetic spectral plasma solver (sps) code, demonstrate that the turbulent cascade in such regimes can reach scales smaller than the electron inertial scale, and results in the formation of electron-scale current sheets (ESCS). Statistical analysis of the geometrical properties of the detected ESCS is performed using an algorithm based on the medial axis transform. A typical half-thickness of the current sheets is found to be on the order of electron inertial length or below, while their half-length falls between the electron and ion inertial length. The pressure–strain interaction, used as a measure of energy dissipation, exhibits high intermittency, with the majority of the total energy exchange occurring in current structures occupying approximately 20 per cent of the total volume. Some of the current sheets corresponding to the largest pressure–strain interaction are found to be associated with Alfvénic electron jets and magnetic configurations typical of reconnection. These reconnection candidates represent about 1 per cent of all the current sheets identified.
Consistency tests for comparing astrophysical models and observations
Authors: Stoppa Fiorenzo , Cator Eric , Nelemans Gijs 
Published: June 2023

ABSTRACT
In astronomy, there is an opportunity to enhance the practice of validating models through statistical techniques, specifically to account for measurement error uncertainties. While models are commonly used to describe observations, there are instances where there is a lack of agreement between the two. This can occur when models are derived from incomplete theories, when a better-fitting model is not available or when measurement uncertainties are not correctly considered. However, with the application of specific tests that assess the consistency between observations and astrophysical models in a model-independent way, it is possible to address this issue. The consistency tests (ConTESTs) developed in this paper use a combination of non-parametric methods and distance measures to obtain a test statistic that evaluates the closeness of the astrophysical model to the observations. To draw conclusions on the consistency hypothesis, a simulation-based methodology is performed. In particular, we built two tests for density models and two for regression models to be used depending on the case at hand and the power of the test needed. We used ConTEST to examine synthetic examples in order to determine the effectiveness of the tests and provide guidance on using them while building a model. We also applied ConTEST to various astronomy cases, identifying which models were consistent and, if not, identifying the probable causes of rejection.
Using the motion of S2 to constrain scalar clouds around Sgr A*
Authors: Foschi A , Abuter R , Aimar N , Amaro Seoane P , Amorim A , Bauböck M , Berger J P , Bonnet H , Bourdarot G , Brandner W , Cardoso V , Clénet Y , Dallilar Y , Davies R , de Zeeuw P T , Defrère D , Dexter J , Drescher A , Eckart A , Eisenhauer F , Ferreira M C , Förster Schreiber N M , Garcia P J V , Gao F , Gendron E , Genzel R , Gillessen S , Gomes T , Habibi M , Haubois X , Heißel G , Henning T , Hippler S , Hönig S F , Horrobin M , Jochum L , Jocou L , Kaufer A , Kervella P , Kreidberg L , Lacour S , Lapeyrère V , Le Bouquin J -B , Léna P , Lutz D , Millour F , Ott T , Paumard T , Perraut K , Perrin G , Pfuhl O , Rabien S , Ribeiro D C , Sadun Bordoni M , Scheithauer S , Shangguan J , Shimizu T , Stadler J , Straub O , Straubmeier C , Sturm E , Sykes C , Tacconi L J , Vincent F , von Fellenberg S , Widmann F , Wieprecht E , Wiezorrek E , Woillez J ,   GRAVITY Collaboration
Published: June 2023

ABSTRACT
The motion of S2, one of the stars closest to the Galactic Centre, has been measured accurately and used to study the compact object at the centre of the Milky Way. It is commonly accepted that this object is a supermassive black hole, but the nature of its environment is open to discussion. Here, we investigate the possibility that dark matter in the form of an ultralight scalar field ‘cloud’ clusters around Sgr A*. We use the available data for S2 to perform a Markov Chain Monte Carlo analysis and find the best-fit estimates for a scalar cloud structure. Our results show no substantial evidence for such structures. When the cloud size is on the order of the size of the orbit of S2, we are able to constrain its mass to be smaller than 0.1 % of the central mass, setting a strong bound on the presence of new fields in the galactic centre.
Light and colour of cirrus, translucent, and opaque dust in the high-latitude area of LDN 1642
Authors: Mattila K , Väisänen P , Lehtinen K , Haikala L , Haas M 
Published: June 2023

ABSTRACT
We have performed a 5-colour surface photometric study of the high-galactic-latitude area of dark nebula LDN 1642. Scattered light properties are presented of diffuse, translucent, and opaque dust over the range of 3500–5500 Å . Far infrared absolute photometry at 200 µm improves the precision of and provides a zero point to the extinction. The intensity of the scattered light depends on dust column density in a characteristic way: for optically thin dust the intensity first increases linearly, then turns to a saturation value; at still larger extinctions the intensity turns down to a slow decrease. The AV value of the saturated intensity maximum shifts in a systematic way, from AV ≈ 1.5 mag at 3500 Å to ∼3 mag at 5500 Å . The intensity curves offer a straight-forward explanation for the behaviour of the scattered-light colours. At the intensity peak the colour agrees with the integrated starlight colour, while it is bluer at the low- and redder at the high-column-density side of the peak, respectively. These colour changes are a direct consequence of the wavelength dependence of the extinction. We have compared the colours of the LDN 1642 area with other relevant observational studies: high-latitude diffuse/translucent clouds, wide-field cirrus dust; and externally illuminated AGB-star envelopes. For extragalactic low-surface-brightness sources cirrus is an unwanted foreground contaminant. Our results for cirrus colours can help to distinguish cases where a diffuse plume or stream, apparently associated with a galaxy or a group or cluster, is more likely a local cirrus structure.
Close encounters of black hole—star binaries with stellar-mass black holes
Authors: Ryu Taeho , Valli Ruggero , Pakmor Rüdiger , Perna Rosalba , de Mink Selma E , Springel Volker 
Published: June 2023

ABSTRACT
Dynamical interactions involving binaries play a crucial role in the evolution of star clusters and galaxies. We continue our investigation of the hydrodynamics of three-body encounters, focusing on binary black hole (BBH) formation, stellar disruption, and electromagnetic (EM) emission in dynamical interactions between a BH-star binary and a stellar-mass BH, using the moving-mesh hydrodynamics code AREPO. This type of encounters can be divided into two classes depending on whether the final outcome includes BBHs. This outcome is primarily determined by which two objects meet at the first closest approach. BBHs are more likely to form when the star and the incoming BH encounter first with an impact parameter smaller than the binary’s semimajor axis. In this case, the star is frequently disrupted. On the other hand, when the two BHs encounter first, frequent consequences are an orbit perturbation of the original binary or a binary member exchange. For the parameters chosen in this study, BBH formation, accompanied by stellar disruption, happens in roughly one out of four encounters. The close correlation between BBH formation and stellar disruption has possible implications for EM counterparts at the binary’s merger. The BH that disrupts the star is promptly surrounded by an optically and geometrically thick disc with accretion rates exceeding the Eddington limit. If the debris disc cools fast enough to become long-lived, EM counterparts can be produced at the time of the BBH merger.
Photometric variability of blue straggler stars in M67 with TESS and K2
Authors: Vernekar Nagaraj , Subramaniam Annapurni , Jadhav Vikrant V , Bowman Dominic M 
Published: June 2023

ABSTRACT
Blue straggler stars (BSSs) are formed through mass transfers or mergers in binaries. The recent detections of white dwarf (WD) companions to BSSs in M67 suggested a mass transfer pathway of formation. In search of a close companion to five BSSs in M67 that are known to be spectroscopic binaries, we study the light curves from K2 and TESS data. We use PHOEBE to analyse the light curves and estimate the properties of the companions. We detect variability in WOCS 1007, and the light curve is dominated by ellipsoidal variation. Using the light curve and radial velocity measurements, we estimate its orbital period to be 4.212 ± 0.041 d and e = 0.206 ± 002. The mass of the companion is estimated to be 0.22 ± 0.05 M⊙ with a radius of 0.078 ± 0.027 R⊙, confirming it to be an LM WD with Teff = 14300 ± 1100 K. The estimated mass of the BSS, 1.95 ± 0.26 M⊙, is similar to that estimated from isochrones. The BSS in WOCS 1007 shows δ Scuti pulsations, although it is slightly deformed and likely to be formed through an efficient mass transfer. Though we detect a light curve for WOCS 4003 showing grazing eclipse with ellipsoidal variation, the estimated parameters are inconclusive. Apart from the 0.44 d period, we found smaller eclipses with a period of 1.1 d, suggesting a compact triple system. In the cases of WOCS 4003, WOCS 5005, and WOCS 1025, no eclipses or pulsations are detected, confirming the absence of any short-period inner binary with high inclination in these BSSs.
Swift J1644+57 as an off-axis Jet
Authors: Beniamini Paz , Piran Tsvi , Matsumoto Tatsuya 
Published: June 2023

ABSTRACT
One of the intriguing puzzles concerning Swift J1644+57, the first jetted tidal disruption event (TDE) discovered, is the constant increase in its jet energy, as implied by radio observations. During the first two hundred days, the jet energy has increased by an order of magnitude. We suggest that the jet was viewed slightly off-axis. In this case, the apparent energy increase arises due to the slowing down of the jet and the corresponding broadening of its beaming cone. Using equipartition analysis, we infer an increasing jet energy as a larger region of the jet is observed. A simple off-axis model accounts nicely for the multi-wavelength radio observations, resolving this long-standing puzzle. The model allows us to self-consistently evolve the synchrotron signature from an off-axis jet as a function of time. It also allows us to estimate, for the first time, the beaming angle of the jet, θ0 ≈ 21°. Considering existing limits on the black hole mass, ≲107 M⊙, this angle implies that the prompt phase beaming corrected luminosity of Swift J1644+57, ∼1047 ergs sec−1, was super Eddington. We also present a closure relation between the spectral and temporal flux for off-axis jets, which can be used to test whether a given radio transient is off-axis or not.
RNase H1 facilitates recombinase recruitment by degrading DNA–RNA hybrids during meiosis
Authors: Liu Chao , Wang Liying , Li Yanan , Guo Mengmeng , Hu Jun , Wang Teng , Li Mengjing , Yang Zhuo , Lin Ruoyao , Xu Wei , Chen Yinghong , Luo Mengcheng , Gao Fei , Chen Jia-Yu , Sun Qianwen , Liu Hongbin , Sun Bo , Li Wei 
Published: June 2023

Abstract
DNA–RNA hybrids play various roles in many physiological progresses, but how this chromatin structure is dynamically regulated during spermatogenesis remains largely unknown. Here, we show that germ cell-specific knockout of Rnaseh1, a specialized enzyme that degrades the RNA within DNA–RNA hybrids, impairs spermatogenesis and causes male infertility. Notably, Rnaseh1 knockout results in incomplete DNA repair and meiotic prophase I arrest. These defects arise from the altered RAD51 and DMC1 recruitment in zygotene spermatocytes. Furthermore, single-molecule experiments show that RNase H1 promotes recombinase recruitment to DNA by degrading RNA within DNA–RNA hybrids and allows nucleoprotein filaments formation. Overall, we uncover a function of RNase H1 in meiotic recombination, during which it processes DNA–RNA hybrids and facilitates recombinase recruitment.
Alteration of replication protein A binding mode on single-stranded DNA by NSMF potentiates RPA phosphorylation by ATR kinase
Authors: Kang Yujin , Han Ye Gi , Khim Keon Woo , Choi Woo Gyun , Ju Min Kyung , Park Kibeom , Shin Kyeong Jin , Chae Young Chan , Choi Jang Hyun , Kim Hongtae , Lee Ja Yil 
Published: June 2023

Abstract
Replication protein A (RPA), a eukaryotic single-stranded DNA (ssDNA) binding protein, dynamically interacts with ssDNA in different binding modes and plays essential roles in DNA metabolism such as replication, repair, and recombination. RPA accumulation on ssDNA due to replication stress triggers the DNA damage response (DDR) by activating the ataxia telangiectasia and RAD3-related (ATR) kinase, which phosphorylates itself and downstream DDR factors, including RPA. We recently reported that the N-methyl-D-aspartate receptor synaptonuclear signaling and neuronal migration factor (NSMF), a neuronal protein associated with Kallmann syndrome, promotes RPA32 phosphorylation via ATR upon replication stress. However, how NSMF enhances ATR-mediated RPA32 phosphorylation remains elusive. Here, we demonstrate that NSMF colocalizes and physically interacts with RPA at DNA damage sites in vivo and in vitro. Using purified RPA and NSMF in biochemical and single-molecule assays, we find that NSMF selectively displaces RPA in the more weakly bound 8- and 20-nucleotide binding modes from ssDNA, allowing the retention of more stable RPA molecules in the 30-nt binding mode. The 30-nt binding mode of RPA enhances RPA32 phosphorylation by ATR, and phosphorylated RPA becomes stabilized on ssDNA. Our findings provide new mechanistic insight into how NSMF facilitates the role of RPA in the ATR pathway.
dsRNA-induced immunity targets plasmodesmata and is suppressed by viral movement proteins
Authors: Huang Caiping , Sede Ana Rocío , Elvira-González Laura , Yan Yan , Rodriguez Miguel Eduardo , Mutterer Jérôme , Boutant Emmanuel , Shan Libo , Heinlein Manfred 
Published: June 2023

Abstract
Emerging evidence indicates that in addition to its well-recognized functions in antiviral RNA silencing, dsRNA elicits pattern-triggered immunity (PTI), likely contributing to plant resistance against virus infections. However, compared to bacterial and fungal elicitor-mediated PTI, the mode-of-action and signaling pathway of dsRNA-induced defense remain poorly characterized. Here, using multicolor in vivo imaging, analysis of GFP mobility, callose staining, and plasmodesmal marker lines in Arabidopsis thaliana and Nicotiana benthamiana, we show that dsRNA-induced PTI restricts the progression of virus infection by triggering callose deposition at plasmodesmata, thereby likely limiting the macromolecular transport through these cell-to-cell communication channels. The plasma membrane-resident SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE 1, the BOTRYTIS INDUCED KINASE1/AVRPPHB SUSCEPTIBLE1-LIKE KINASE1 kinase module, PLASMODESMATA-LOCATED PROTEINs 1/2/3, as well as CALMODULIN-LIKE 41 and Ca2+ signals are involved in the dsRNA-induced signaling leading to callose deposition at plasmodesmata and antiviral defense. Unlike the classical bacterial elicitor flagellin, dsRNA does not trigger a detectable reactive oxygen species (ROS) burst, substantiating the idea that different microbial patterns trigger partially shared immune signaling frameworks with distinct features. Likely as a counter strategy, viral movement proteins from different viruses suppress the dsRNA-induced host response leading to callose deposition to achieve infection. Thus, our data support a model in which plant immune signaling constrains virus movement by inducing callose deposition at plasmodesmata and reveals how viruses counteract this layer of immunity.
VERNALIZATION1 represses FLOWERING PROMOTING FACTOR1-LIKE1 in leaves for timely flowering in Brachypodium distachyon
Authors: Liu Shu , Chen Siyi , Zhou Yang , Shen Yuxin , Qin Zhengrui , Wu Liang 
Published: June 2023

Abstract
FLOWERING PROMOTING FACTOR1 (FPF1), a small protein without any known domains, promotes flowering in several plants; however, its functional mechanism remains unknown. Here, we characterized 2 FPF1-like proteins, FPL1 and FPL7, which, in contrast, function as flowering repressors in Brachypodium distachyon. FPL1 and FPL7 interact with the components of the florigen activation complex (FAC) and inhibit FAC activity to restrict expression of its critical target, VERNALIZATION1 (VRN1), in leaves, thereby preventing overaccumulation of FLOWERING LOCUS T1 (FT1) at the juvenile stage. Further, VRN1 can directly bind to the FPL1 promoter and repress FPL1 expression; hence, as VRN1 gradually accumulates during the late vegetative stage, FAC is released. This accurate feedback regulation of FPL1 by VRN1 allows proper FT1 expression in leaves and ensures sufficient FAC formation in shoot apical meristems to trigger timely flowering. Overall, we define a sophisticated modulatory loop for flowering initiation in a temperate grass, providing insights toward resolving the molecular basis underlying fine-tuning flowering time in plants.
A machine learning approach to galactic emission-line region classification
Authors: Rhea Carter L , Rousseau-Nepton Laurie , Moumen Ismael , Prunet Simon , Hlavacek-Larrondo Julie , Grasha Kathryn , Robert Carmelle , Morisset Christophe , Stasinska Grazyna , Vale-Asari Natalia , Giroux Justine , McLeod Anna , Gendron-Marsolais Marie-Lou , Wang Junfeng , Lyman Joe , Chemin Laurent 
Published: June 2023

Abstract
Diagnostic diagrams of emission-line ratios have been used extensively to categorize extragalactic emission regions; however, these diagnostics are occasionally at odds with each other due to differing definitions. In this work, we study the applicability of supervised machine-learning techniques to systematically classify emission-line regions from the ratios of certain emission lines. Using the Million Mexican Model database, which contains information from grids of photoionization models using cloudy, and from shock models, we develop training and test sets of emission line fluxes for three key diagnostic ratios. The sets are created for three classifications: classic H ii regions, planetary nebulae, and supernova remnants. We train a neural network to classify a region as one of the three classes defined above given three key line ratios that are present both in the SITELLE and MUSE instruments’ band-passes: [O iii]λ5007/H β, [N ii]λ6583/H α, ([S ii]λ6717+[S ii]λ6731)/H α. We also tested the impact of the addition of the [O ii]λ3726, 3729/[O iii]λ5007 line ratio when available for the classification. A maximum luminosity limit is introduced to improve the classification of the planetary nebulae. Furthermore, the network is applied to SITELLE observations of a prominent field of M33. We discuss where the network succeeds and why it fails in certain cases. Our results provide a framework for the use of machine learning as a tool for the classification of extragalactic emission regions. Further work is needed to build more comprehensive training sets and adapt the method to additional observational constraints.
Making sense of knowledge-brokering organisations: boundary organisations or policy entrepreneurs?
Authors: MacKillop Eleanor , Connell Andrew , Downe James , Durrant Hannah 
Published: June 2023

Abstract
Knowledge-brokering organisations (KBOs) have multiplied in the evidence–policy landscape worldwide, changing how decision-makers are accessing evidence. Yet, we still know little about their emergence and roles. This research helps to understand KBOs and their place in evidence-based policymaking by highlighting the varied work that they do, the relationships they cultivate with policymakers, the complex knowledge-brokering processes they negotiate, and how they establish their credibility in different ways. We build on boundary organisation theory and the concept of policy entrepreneur (PE) (drawn from the multiple streams analysis) to develop a better understanding of KBOs who play multiple roles. By using the PE concept, we bring a greater focus on the politics of brokering. This duality involves them in seeking to provide ‘objective’ evidence while simultaneously determining what counts as evidence for policy and making recommendations for political decisions.