bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extracting the Subhalo Mass Function from Strong Lens Images with Image Segmentation
Authors: Ostdiek Bryan , Diaz Rivero Ana , Dvorkin Cora 
Published: March 2022

Abstract
Detecting substructure within strongly lensed images is a promising route to shed light on the nature of dark matter. However, it is a challenging task, which traditionally requires detailed lens modeling and source reconstruction, taking weeks to analyze each system. We use machine learning to circumvent the need for lens and source modeling and develop a neural network to both locate subhalos in an image as well as determine their mass using the technique of image segmentation. The network is trained on images with a single subhalo located near the Einstein ring across a wide range of apparent source magnitudes. The network is then able to resolve subhalos with masses m ≳ 108.5
M
⊙. Training in this way allows the network to learn the gravitational lensing of light, and, remarkably, it is then able to detect entire populations of substructure, even for locations further away from the Einstein ring than those used in training. Over a wide range of the apparent source magnitude, the false-positive rate is around three false subhalos per 100 images, coming mostly from the lightest detectable subhalo for that signal-to-noise ratio. With good accuracy and a low false-positive rate, counting the number of pixels assigned to each subhalo class over multiple images allows for a measurement of the subhalo mass function (SMF). When measured over three mass bins from 109–1010
M
⊙ the SMF slope is recovered with an error of 36% for 50 images, and this improves to 10% for 1000 images with Hubble Space Telescope-like noise.
ALMA Reveals a Large Overdensity and Strong Clustering of Galaxies in Quasar Environments at z ∼ 4
Authors: García-Vergara Cristina , Rybak Matus , Hodge Jacqueline , Hennawi Joseph F. , Decarli Roberto , González-López Jorge , Arrigoni-Battaia Fabrizio , Aravena Manuel , Farina Emanuele P. 
Published: March 2022

Abstract
We present an Atacama Large Millimeter/submillimeter Array (ALMA) survey of CO(4–3) line emitting galaxies in 17 quasar fields at z ∼ 4 aimed at performing the first systematic search of dusty galaxies in high-z quasar environments. Our blind search of galaxies around the quasars results in five CO emitters with S/N ≥ 5.6 within a projected radius of R ≲ 1.5 h
−1 cMpc and a velocity range of δv = ±1000 km s−1 around the quasar. In blank fields, we expect to detect only 0.28 CO emitters within the same volume, implying a total overdensity of

17.6

−
7.6

+
11.9

in our fields, and indicating that quasars trace massive structures in the early universe. We quantify this overdensity by measuring the small-scale clustering of CO emitters around quasars, resulting in a cross-correlation length of

r

0
,
QG

=

8.37

−
2.04

+
2.42

h

−
1

cMpc, assuming a fixed slope γ = 1.8. This contradicts the reported mild overdensities (x1.4) of Lyα emitters (LAEs) in the same fields at scales of R ≲ 7 h
−1 cMpc, which are well described by a cross-correlation length

3.0

−
1.4

+
1.5

times lower than that measured for CO emitters. We discuss some possibilities to explain this discrepancy, including low star formation efficiency, and excess of dust in galaxies around quasars. Finally, we constrain, for the first time, the clustering of CO emitters at z ∼ 4, finding an autocorrelation length of r
0,CO = 3.14 ±1.71 h
−1 cMpc (with γ = 1.8). Our work, together with the previous study of LAEs around quasars, traces simultaneously the clustering properties of both optical and dusty galaxy populations in quasars fields, stressing the importance of multiwavelength studies, and highlighting important questions about galaxy properties in high-z dense environments.
Flexible and Accurate Evaluation of Gravitational-wave Malmquist Bias with Machine Learning
Authors: Talbot Colm , Thrane Eric 
Published: March 2022

Abstract
Many astronomical surveys are limited by the brightness of the sources, and gravitational-wave searches are no exception. The detectability of gravitational waves from merging binaries is affected by the mass and spin of the constituent compact objects. To perform unbiased inference on the distribution of compact binaries, it is necessary to account for this selection effect, which is known as Malmquist bias. Since systematic error from selection effects grows with the number of events, it will be increasingly important over the coming years to accurately estimate the observational selection function for gravitational-wave astronomy. We employ density estimation methods to accurately and efficiently compute the compact binary coalescence selection function. We introduce a simple pre-processing method, which significantly reduces the complexity of the required machine-learning models. We demonstrate that our method has smaller statistical errors at comparable computational cost than the method currently most widely used allowing us to probe narrower distributions of spin magnitudes. The currently used method leaves 10%–50% of the interesting black hole spin models inaccessible; our new method can probe >99% of the models and has a lower uncertainty for >80% of the models.
The Paschen Jump as a Diagnostic of the Diffuse Nebular Continuum Emission in Active Galactic Nuclei*
Authors: Guo 郭 Hengxiao 恒潇 , Barth Aaron J. , Korista Kirk T. , Goad Michael R. , Cackett Edward M. , Bentz Misty C. , Brandt William N. , Gonzalez-Buitrago D. , Ferland Gary J. , Gelbord Jonathan M. , Ho Luis C. , Horne Keith , Joner Michael D. , Kriss Gerard A. , McHardy Ian , Mehdipour Missagh , Park Daeseong , Remigio Raymond , U Vivian , Vestergaard Marianne 
Published: March 2022

Abstract
Photoionization modeling of active galactic nuclei (AGN) predicts that diffuse continuum (DC) emission from the broad-line region makes a substantial contribution to the total continuum emission from ultraviolet through near-infrared wavelengths. Evidence for this DC component is present in the strong Balmer jump feature in AGN spectra, and possibly from reverberation measurements that find longer lags than expected from disk emission alone. However, the Balmer jump region contains numerous blended emission features, making it difficult to isolate the DC emission strength. In contrast, the Paschen jump region near 8200 Å is relatively uncontaminated by other strong emission features. Here, we examine whether the Paschen jump can aid in constraining the DC contribution, using Hubble Space Telescope Space Telescope Imaging Spectrograph spectra of six nearby Seyfert 1 nuclei. The spectra appear smooth across the Paschen edge, and we find no evidence of a Paschen spectral break or jump in total flux. We fit multicomponent spectral models over the range 6800–9700 Å and find that the spectra can still be compatible with a significant DC contribution if the DC Paschen jump is offset by an opposite spectral break resulting from blended high-order Paschen emission lines. The fits imply DC contributions ranging from ∼10% to 50% at 8000 Å, but the fitting results are highly dependent on assumptions made about other model components. These degeneracies can potentially be alleviated by carrying out fits over a broader wavelength range, provided that models can accurately represent the disk continuum shape, Fe ii emission, high-order Balmer line emission, and other components.
Spectroastrometry and Reverberation Mapping: The Mass and Geometric Distance of the Supermassive Black Hole in the Quasar 3C 273
Authors: Li Yan-Rong , Wang Jian-Min , Songsheng Yu-Yang , Zhang Zhi-Xiang , Du Pu , Hu Chen , Xiao Ming 
Published: March 2022

Abstract
The quasar 3C 273 has been observed with infrared spectroastrometry (SA) of the broad Paα line and optical reverberation mapping (RM) of the broad Hβ line. SA delivers information about the angular size and structure of the Paα broad-line region (BLR), while RM delivers information about the physical size and structure of the Hβ BLR. Based on the fact that the two BLRs share the mass of the supermassive black hole (SMBH) and viewing inclination, a combination of SA and velocity-resolved RM (SARM) thereby allows us to simultaneously determine the SMBH mass and geometric distance through dynamically modeling the two BLRs. We construct a suite of dynamical models with different geometric configurations and apply a Bayesian approach to obtain the parameter inferences. Overall the obtained masses and distances are insensitive to specific BLR configurations but more or less depend on parameterizations of the vertical distributions. The most probable model, chosen in light of the Bayes factor, yields an angular-size distance

log
(

D

A

/

Mpc
)
=

2.83

−
0.28

+
0.32

and an SMBH mass

log
(

M

•

/

M

⊙

)
=

9.06

−
0.27

+
0.21

, which agree with the relationships between SMBH masses and bulge properties. The BLRs have an inclination of

5

−
1

+
1

degrees, consistent with that of the large-scale jet in 3C 273. Our approach reinforces the capability of SARM analysis to measure SMBH masses and distances of active galactic nuclei and quasars even though SA and RM observations are undertaken with different emission lines and/or in different periods.
A Systematic Exploration of Kilonova Candidates from Neutron Star Mergers during the Third Gravitational-wave Observing Run
Authors: Rastinejad J. C. , Paterson K. , Fong W. , Sand D. J. , Lundquist M. J. , Hosseinzadeh G. , Christensen E. , Daly P. N. , Gibbs A. R. , Hall S. , Shelly F. , Yang S. 
Published: March 2022

Abstract
We present a comprehensive analysis of 653 optical candidate counterparts reported during the third gravitational-wave (GW) observing run. Our sample concentrates on candidates from the 15 events (published in GWTC-2, GWTC-3, or not retracted on GraceDB) that had a >1% chance of including a neutron star in order to assess their viability as true kilonovae. In particular, we leverage tools available in real time, including pre-merger detections and cross-matching with catalogs (i.e., point-source, variable-star, quasar and host-galaxy redshift data sets), to eliminate 65% of candidates in our sample. We further employ spectroscopic classifications, late-time detections, and light-curve behavior analyses and conclude that 66 candidates remain viable kilonovae. These candidates lack sufficient information to determine their classifications, and the majority would require luminosities greater than that of AT 2017gfo. Pre-merger detections in public photometric survey data and comparison of cataloged host-galaxy redshifts with the GW event distances are critical to incorporate into vetting procedures, as these tools eliminated >20% and >30% of candidates, respectively. We expect that such tools that leverage archival information will significantly reduce the strain on spectroscopic and photometric follow-up resources in future observing runs. Finally, we discuss the critical role prompt updates from GW astronomers to the EM community play in reducing the number of candidates requiring vetting.
A Search for Correlated Low-energy Electron Antineutrinos in KamLAND with Gamma-Ray Bursts
Authors: Abe S. , Asami S. , Gando A. , Gando Y. , Gima T. , Goto A. , Hachiya T. , Hata K. , Hosokawa K. , Ichimura K. , Ieki S. , Ikeda H. , Inoue K. , Ishidoshiro K. , Kamei Y. , Kawada N. , Kishimoto Y. , Kinoshita T. , Koga M. , Maemura N. , Mitsui T. , Miyake H. , Nakamura K. , Nakamura K. , Nakamura R. , Ozaki H. , Sakai T. , Sambonsugi H. , Shimizu I. , Shirai J. , Shiraishi K. , Suzuki A. , Suzuki Y. , Takeuchi A. , Tamae K. , Eizuka M. , Kurasawa M. , Nakahata T. , Futagi S. , Watanabe H. , Yoshida Y. , Obara S. , Ichikawa A. K. , Yoshida S. , Umehara S. , Fushimi K. , Berger B. E. , Fujikawa B. K. , Learned J. G. , Maricic J. , Axani S. N. , Smolsky J. , Laber-Smith C. , Winslow L. A. , Fu Z. , Ouellet J. , Efremenko Y. , Karwowski H. J. , Markoff D. M. , Tornow W. , Li A. , Detwiler J. A. , Enomoto S. , Decowski M. P. , Grant C. , Song H. , O’Donnell T. , Dell’Oro S. ,   (KamLAND Collaboration)
Published: March 2022

Abstract
We present the results of a time-coincident event search for low-energy electron antineutrinos in the KamLAND detector with gamma-ray bursts (GRBs) from the Gamma-ray Coordinates Network and Fermi Gamma-ray Burst Monitor. Using a variable coincidence time window of ±500 s plus the duration of each GRB, no statistically significant excess above the background is observed. We place the world’s most stringent 90% confidence level upper limit on the electron antineutrino fluence below 17.5 MeV. Assuming a Fermi–Dirac neutrino energy spectrum from the GRB source, we use the available redshift data to constrain the electron antineutrino luminosity and effective temperature.
GOLDRUSH. IV. Luminosity Functions and Clustering Revealed with ∼4,000,000 Galaxies at z ∼ 2–7: Galaxy–AGN Transition, Star Formation Efficiency, and Implication for Evolution at z > 10
Authors: Harikane Yuichi , Ono Yoshiaki , Ouchi Masami , Liu Chengze , Sawicki Marcin , Shibuya Takatoshi , Behroozi Peter S. , He Wanqiu , Shimasaku Kazuhiro , Arnouts Stephane , Coupon Jean , Fujimoto Seiji , Gwyn Stephen , Huang Jiasheng , Inoue Akio K. , Kashikawa Nobunari , Komiyama Yutaka , Matsuoka Yoshiki , Willott Chris J. 
Published: March 2022

Abstract
We present new measurements of rest-UV luminosity functions and angular correlation functions from 4,100,221 galaxies at z ∼ 2–7 identified in the Subaru/Hyper Suprime-Cam survey and CFHT Large Area U-band Survey. The obtained luminosity functions at z ∼ 4–7 cover a very wide UV luminosity range of ∼

0.002
–
2000

L

UV

*

combined with previous studies, confirming that the dropout luminosity function is a superposition of the active galactic nucleus (AGN) luminosity function dominant at M
UV ≲ −24 mag and the galaxy luminosity function dominant at M
UV ≳ −22 mag, consistent with galaxy fractions based on 1037 spectroscopically identified sources. Galaxy luminosity functions estimated from the spectroscopic galaxy fractions show the bright-end excess beyond the Schechter function at ≳2σ levels, possibly made by inefficient mass quenching, low dust obscuration, and/or hidden AGN activity. By analyzing the correlation functions at z ∼ 2–6 with HOD models, we find a weak redshift evolution (within 0.3 dex) of the ratio of the star formation rate (SFR) to the dark matter accretion rate,

SFR

/

M

̇

h

, indicating the almost constant star formation efficiency at z ∼ 2–6, as suggested by our earlier work at z ∼ 4–7. Meanwhile, the ratio gradually increases with decreasing redshift at z < 5 within 0.3 dex, which quantitatively reproduces the cosmic SFR density evolution, suggesting that the redshift evolution is primarily driven by the increase of the halo number density due to the structure formation, and the decrease of the accretion rate due to the cosmic expansion. Extrapolating this calculation to higher redshifts assuming the constant efficiency suggests a rapid decrease of the SFR density at z > 10 with ∝ 10−0.5(1+z), which will be directly tested with the James Webb Space Telescope.
Periodic Oscillations in LASCO Coronal Mass Ejection Speeds: Space Seismology
Authors: Michalek Grzegorz , Gopalswamy Nat , Yashiro Seiji 
Published: March 2022

Abstract
Coronal mass ejections (CMEs) are energetic eruptions of organized magnetic structures from the Sun. Therefore, the reconnection of the magnetic field during ejection can excite periodic speed oscillations of CMEs. A previous study showed that speed oscillations are frequently associated with CME propagation. The Solar and Heliospheric Observatory mission’s white-light coronagraphs have observed about 30,000 CMEs from 1996 January to the end of 2019 December. This period of time covers two solar cycles (23 and 24). In the present study, the basic attributes of speed oscillations during this period of time were analyzed. We showed that the oscillation parameters (period and amplitude) significantly depend not only on the phase of a given solar cycle but also on the intensity of individual cycles as well. This reveals that the basic attributes of speed oscillation are closely related to the physical conditions prevailing inside the CMEs as well as in the interplanetary medium in which they propagate. Using this approximation, we estimated that, on average, the CME internal magnetic field varies from 18 up to 25 mG between minimum and maximum solar activity. The obtained results show that a detailed analysis of speed oscillations can be a very efficient tool for studying not only the physical properties of the ejections themselves but also the condition of the interplanetary medium in which they expand. This creates completely new perspectives for studying the physical parameters of CMEs shortly after their eruption in the Sun’s environment (space seismology).
Core Electron Heating by Triggered Ion Acoustic Waves in the Solar Wind
Authors: Mozer F. S. , Bale S. D. , Cattell C. A. , Halekas J. , Vasko I. Y. , Verniero J. L. , Kellogg P. J. 
Published: March 2022

Abstract
Perihelion passes on Parker Solar Probe orbits 6–9 have been studied to show that solar wind core electrons emerged from 15 solar radii with a temperature of 55 ± 5 eV, independent of the solar wind speed, which varied from 300 to 800 km s−1. After leaving 15 solar radii and in the absence of triggered ion acoustic waves at greater distances, the core electron temperature varied with radial distance, R, in solar radii, as 1900R
−4/3 eV because of cooling produced by the adiabatic expansion. The coefficient, 1900, reproduces the minimum core electron perpendicular temperature observed during the 25 days of observation. In the presence of triggered ion acoustic waves, the core electrons were isotropically heated as much as a factor of two above the minimum temperature, 1900R
−4/3 eV. Triggered ion acoustic waves were the only waves observed in coincidence with the core electron heating. They are the dominant wave mode at frequencies greater than 100 Hz at solar distances between 15 and 30 solar radii.
Early Warnings of Binary Neutron Star Coalescence Using the SPIIR Search
Authors: Kovalam Manoj , Kaium Patwary Md Anwarul , Sreekumar Anala K. , Wen Linqing , Panther Fiona H. , Chu Qi 
Published: March 2022

Abstract
Gravitational waves from binary neutron star mergers can be used as alerts to enable prompt follow-up observations. In particular, capturing prompt electromagnetic and astroparticle emissions from the moment of a binary merger presents unique constraints on the timescale and sky localization for online gravitational-wave detection. Here we present the expected performance of the SPIIR online detection pipeline that is designed for this purpose in the upcoming international LIGO–Virgo’s 4th Science Run (O4). Using simulated Gaussian data for the two LIGO observatories with expected O4 sensitivity, we demonstrate that there is a nonnegligible opportunity to deliver premerger warnings at least 10 s before the final plunge. These alerts are expected to be issued at a nominal rate of one binary neutron star coalescence per year and localized within a median searched area of 300 deg2. We envision such detection to be extremely useful for follow-up observatories with a large field of view such as the Murchison Widefield Array radio facility in Western Australia.
The nationwide ‘ZNIEFF’ inventory in France: an open dataset of more than one million species data in zones of high ecological value
Authors: Lepareur Fanny , Manceau Mathieu , Reyjol Yorick , Touroult Julien , Robert Solène , Vest Frédéric , Horellou Arnaud , Poncet Laurent 
Published: March 2022

In France, a ‘natural zone of ecological, faunistic or floristic value’ (Zone Naturelle d'Intérêt Écologique, Faunistique et Floristique - ZNIEFF) is a natural area, regionally known for its remarkable ecological characteristics. The ZNIEFF inventory is a naturalist and scientific survey programme launched in 1982 by the Ecology Ministry, with support from the French National Museum of Natural History (MNHN).
This paper describes the ZNIEFF national dataset, which comprises 1,013,725 data for various animal (38%), plant (59%) and fungal (2%) species in terrestrial and marine zones (May 2020). A total of 19,842 sites throughout continental France. as well as in the overseas Departments and territories (Guadeloupe, Martinique, Mayotte, La Réunion, French Guiana, Saint-Martin, Saint-Barthélemy and Saint-Pierre-et-Miquelon), are included in the ZNIEFF dataset (May 2020). This dataset is now available in open access.
All data were collected by skilled naturalists using professional protocols over almost 40 years. They consist mainly of observations of rare, threatened or endemic species, all validated by regional experts. Data are updated twice a year after national validation in both national (INPN-OpenObs) and global (GBIF) biodiversity web platforms. Some of the observed species, the so-called ‘trigger species’ or ‘determinant’ species, are of central interest for a site to be designated a ZNIEFF (zone of high ecological value). This concerns more than 35,000 taxa, mainly angiosperms, insects, fungi, birds and fish.
Plant diversity and structure in desert communities of the Andean piedmont in Ica, Peru
Authors: Montenegro-Hoyos Angie , Vega Nanette , Linares-Palomino Reynaldo 
Published: March 2022

Aims: There is extensive documentation of the floristic composition and plant diversity patterns in the South American coastal deserts and the adjoining arid Puna. Surprisingly, the vegetation along the transition zone from these deserts in the coastal lowlands to the Puna highlands has been little studied. The main goal of this study was to characterize and compare the structure of plant communities in two localities in the Ica department, with the aim of contributing to the floristic knowledge of the desertic western Andean slopes along the lowlands to Andean transition zone.Study area: Huancacasa and La Bolivar localities located at approximately 740 and 3,000 m a.s.l. in the Ica department, Peru.Methods: We sampled 10 plots of 100 m × 60 m located between 740–1,600 m a.s.l. in La Bolivar and 15 modified Whittaker plots (MWPs) of 20 m × 5 m located between 2,800–3,000 m a.s.l. in Huancacasa and recorded species richness and abundance. We estimated alpha diversity, performed Non-Metric Multidimensional Scaling (NMDS) and one-way Similarity (ANOSIM) analyses and plotted rank-abundance curves.Results: We recorded 215 species and morphospecies with coastal and Andean distribution, including 43 species (21.3%) that are either considered endemic to Peru or have been considered under some form of threat by Peruvian or international standards. Both plant communities differed in terms of composition, species richness, abundance, and dominant growth form, with higher values in the communities located at higher elevations. We added 83 species as new records for the Ica department.Conclusions: Our research reinforced the need to increase exploration and documentation of the vegetation within the lowland to highland transition zone along the dry western slopes of the Andes. Our results from such a transition in Ica department in southern Peru, show that much of its plant diversity seems to be, as yet, largely unknown.Taxonomic reference: The Plant List (2013).Abbreviations: ANOSIM = one-way Analysis of Similarities; BMAP = Biodiversity Monitoring and Assessment Program; IUCN = International Union for Conservation of Nature; NMDS = Non-Metric Multidimensional Scaling; USM = Universidad Nacional Mayor de San Marcos (Herbarium).