bluuebunny/crossref_metadata_2025 huggingface dataset:
Core-halo boundary in a sheet beam model
Authors: Carlan Antônio H. , Pakter Renato
Published: November 2021

In this paper, halo formation in a sheet beam model is investigated. Special attention is given to the core-halo boundary. In particular, a theory to determine the final stationary state achieved by an initially mismatched beam is developed. An interesting property of the theory is that it clearly separates the core and the halo portions of the distribution. Self-consistent numerical simulations are employed to obtain particle distributions for the sheet beam stationary state. Using the maximum Laplacian criteria, the core-halo boundary is evaluated from the numerical data for both one-dimensional projections of the beam distribution as well as the full multi-dimensional phase space. The results are compared to those predicted by the theory.
Strain-controlled domain wall injection into nanowires for sensor applications
Authors: Masciocchi Giovanni , Fattouhi Mouad , Kehlberger Andreas , Lopez-Diaz Luis , Syskaki Maria-Andromachi , Kläui Mathias
Published: November 2021

We investigate experimentally the effects of strain on the injection of 180° domain walls (DWs) from a nucleation pad into magnetic nanowires, as typically used for DW-based sensors. In our study, the strain, generated by substrate bending, induces in the material a uniaxial anisotropy due to magnetoelastic coupling. To compare the strain effects, Co40Fe40B20, Ni, and Ni82Fe18 samples with in-plane magnetization and different magnetoelastic coupling are deposited. In these samples, we measure the magnetic field required for the injection of a DW, by imaging using differential contrast in a magneto-optical Kerr microscope. We find that strain increases the DW injection field and that the switching mechanism depends strongly on the strain direction. We observe that low magnetic anisotropy facilitates the creation of a domain wall at the junction between the pad and the wire, whereas a strain-induced magnetic easy axis significantly increases the coercive field of the nucleation pad. Moreover, we find that these effects of strain-induced anisotropy can be counteracted by an additional magnetic uniaxial anisotropy perpendicular to the strain-induced easy axis. We perform micromagnetic simulations to support the interpretation of our experimental findings showing that the above described observations can be explained by the effective anisotropy in the device. The anisotropy influences the switching mechanism in the nucleation pad as well as the pinning of the DW at the wire entrance. As the DW injection is a key operation for sensor performances, the observations show that strain is imposing a lower limit for the sensor field operating window.
Predicting space-charge affected field emission current from curved tips
Authors: Biswas Debabrata , Kumar Raghwendra , Singh Gaurav
Published: November 2021

Field-emission studies incorporating the effect of space charge reveal that for planar emitters, the steady-state field EP, after initial transients, settles down to a value lower than the vacuum field EL. The ratio ϑ=EP/EL is a measure of the severity of space-charge effect, with ϑ=0 being the most severe and ϑ≃1 denoting the lack of significant effect. While EL can be determined from a single numerical evaluation of the Laplace equation, EP is largely an unknown quantity whose value can be approximately found using physical models or can be determined “exactly” by particle-in-cell or molecular dynamics codes. We propose here a simple model that applies to planar as well as curved emitters based on an application of Gauss’s law. The model is then refined using simple approximations for the magnitude of the anode field and the spread of the beam when it reaches the anode. The predictions are compared with existing molecular dynamics results for the planar case and particle-in-cell simulation results using PASUPAT for curved emitters. In both cases, the agreement is good. The method may also be applied to large area field emitters if the individual enhancement factors are known, for instance, using the hybrid model [D. Biswas, J. Vac. Sci. Technol. B 38, 063201 (2020)].
Effect of varying Bi content on the temperature-dependent mechanical, dielectric, and structural properties of nominal Na1/2Bi1/2TiO3
Authors: Gadelmawla Ahmed , Riess Kevin , Birkenstock Johannes , Hinterstein Manuel , Webber Kyle G. , Khansur Neamul H.
Published: November 2021

Na1/2Bi1/2TiO3 (NBT) with varying Bi content has gained significant interest as a potential new material for solid-oxide fuel cells and oxygen separation membranes because of its excellent oxygen-ion conductivity. In this work, the effect of varying Bi content in NBT ceramics of compositions Na1/2BixTiO2.25+1.5x, where x = 0.485–0.510, on the temperature-dependent mechanical and dielectric properties and the crystal structure has been investigated, as these applications expose the components to high thermal and mechanical fields. The effects of Bi variation on phase compositions and structural transitions were systematically investigated by scanning electron microscopy-energy dispersive x-ray analyses and neutron diffraction at room temperature, in situ high-temperature x-ray diffraction, dielectric permittivity, and mechanical measurements. In-depth analysis of the temperature-dependent data shows that the Bi content of the samples does not alter the average crystal structure of the NBT; however, the temperature-dependent behavior of the latter depend on variations in Bi content and the associated oxygen vacancy concentration. This change in phase transition temperature displays a good correlation with the temperature-dependent ferroelastic response and with the Bi content.
Societal shifts due to COVID-19 reveal large-scale complexities and feedbacks between atmospheric chemistry and climate change
Authors: Laughner Joshua L. , Neu Jessica L. , Schimel David , Wennberg Paul O. , Barsanti Kelley , Bowman Kevin W. , Chatterjee Abhishek , Croes Bart E. , Fitzmaurice Helen L. , Henze Daven K. , Kim Jinsol , Kort Eric A. , Liu Zhu , Miyazaki Kazuyuki , Turner Alexander J. , Anenberg Susan , Avise Jeremy , Cao Hansen , Crisp David , de Gouw Joost , Eldering Annmarie , Fyfe John C. , Goldberg Daniel L. , Gurney Kevin R. , Hasheminassab Sina , Hopkins Francesca , Ivey Cesunica E. , Jones Dylan B. A. , Liu Junjie , Lovenduski Nicole S. , Martin Randall V. , McKinley Galen A. , Ott Lesley , Poulter Benjamin , Ru Muye , Sander Stanley P. , Swart Neil , Yung Yuk L. , Zeng Zhao-Cheng ,   the rest of the Keck Institute for Space Studies “COVID-19: Identifying Unique Opportunities for Earth System Science” study team
Published: November 2021

Significance

The COVID-19 pandemic and associated lockdowns caused significant changes to human activity that temporarily altered our imprint on the atmosphere, providing a brief glimpse of potential future changes in atmospheric composition. This event demonstrated key feedbacks within and between air quality and the carbon cycle: Improvements in air quality increased the lifetime of methane (an important greenhouse gas), while unusually hot weather and intense wildfires in Los Angeles drove poor air quality. This shows that efforts to reduce greenhouse gas emissions and improve air quality cannot be considered separately.
Gender marking in L1 and L2 French
Authors: Bril Marco
Published: November 2021

Very little is known about the accuracy of grammatical inflection in written language. In this study we investigated the effects of syntactic complexity, lexical category and phonological expression on gender marking in L1 and L2 French. Native speakers of French (n = 40) and Dutch learners of French (n = 45) completed a fill-in-the-gap task in which the test items were controlled for the linguistic factors under investigation. The results showed main effects for syntactic complexity and lexical category. For phonological expression we only observed moderation effects. We conclude that syntactic complexity and lexical category affect the accuracy of gender marking in written L1 and L2 French more than phonological expression.
The acquisition of disjunction under negation and recursive ni in French
Authors: Guasti Maria Teresa , Pagliarini Elena , Durrleman Stephanie
Published: November 2021

Pagliarini, Crain, & Guasti (2018) showed that children acquiring Italian start to attribute a “neither” interpretation to negative disjunctive sentences, but converge to the adult “at least one” interpretation earlier than children acquiring Japanese or Mandarin. This earlier convergence is attributed to the already adult interpretation of a lexical form that expresses the “neither” interpretation unambiguously (recursive né). We further test this proposal with French negated disjunctive sentences, where a similar lexical form (recursive ni) is available, but with different properties than in Italian. We conclude that, for an earlier convergence to the adult interpretation of OR under negation, what matters is the availability of a minimal pair of expressions and not just of an expression that conveys the “neither” meaning.
Introduction
Authors: Borin Lars , Dannélls Dana , Friberg Heppin Karin
Published: November 2021

The Swedish FrameNet++ was designed to be several
things. As a digital artifact, it is an integrated
panchronic lexical macroresource, primarily for Swedish, but
including several other languages, intended as a basic
infrastructural component in Swedish language technology research
and for developing natural language processing applications. As an
activity, it is a long-term R&D initiative,
initially aimed at bringing about this macroresource, and now at
maintaining and extending it, at promoting its use in language
technology research and application development, as well as ensuring
that the results of this research and development in their turn are
incorporated in the macroresource. As a product of
research, it reflects both computational and linguistic
approaches to lexicology, lexical semantics, and lexical
typology.
Swedish FrameNet*
Authors: Dannélls Dana , Borin Lars , Forsberg Markus , Friberg Heppin Karin , Gronostaj Maria Toporowska
Published: November 2021

This chapter describes the development of Swedish
FrameNet. A new framenet project often follows one of two
methodological approaches: (1) extension, through
translation of a different-language – often English – framenet into
the target language, and (2) merging, where the
resource is built from scratch in the target language. Both
approaches have their pros and cons, which have been extensively
discussed in the literature. Swedish FrameNet is mainly developed
through the extension approach, although balanced with the merging
approach. Drawing on the two approaches simultaneously, we describe
how integrated language resources and tools have been exploited to
create and develop Swedish FrameNet: how it was constructed, what it
contains, and the basic assumptions underlying the annotation of its
contents.
NLP for resource building*
Authors: Johansson Richard
Published: November 2021

We evaluate several lexicon-based and
corpus-based methods to automatically induce new lexical units for
Swedish FrameNet, and we see that the best-performing setup uses a
combination of both types of methods. A particular challenge for
Swedish is the absence of a lexical resource such as WordNet;
however, we show that the semantic network Saldo, which is organized
according to lexicographical principles quite different from those
of WordNet, is very useful for our purposes.
Multiword expressions – a tough typological nut for Swedish
FrameNet++*
Authors: Borin Lars
Published: November 2021

Multiword expressions have attracted much
attention in language technology over the last two decades or so,
and in general linguistics, the interest in phraseology – which
includes the linguistic study of multiword expressions – goes back
much further. In our work on the multilingual components of Swedish
FrameNet++, we have strived to adopt a typologically informed view
on multiword expressions. This raises a number of theoretical and
methodological questions, some of which are discussed in this
chapter.
Language learning and teaching with Swedish FrameNet++
Authors: Prentice Julia , Håkansson Camilla , Lindström Tiedemann Therese , Pilán Ildikó , Volodina Elena
Published: November 2021

This chapter describes and discusses the use of
resources connected to Swedish FrameNet++ (SweFN++) in the context of
the teaching and learning of language proficiency and grammatical
analysis in Swedish. We illustrate the way in which different
resources in the SweFN++ context can be useful for language
pedagogy, by employing two examples, the Swedish Constructicon and a
semantic role exercise on the intelligent computer assisted language
learning (ICALL) platform Lärka. These resources make use of the
infrastructure developed within SweFN++ in fundamentally different
ways, which are discussed and compared. In addition, we discuss the
possibilities for further development of the language pedagogical
potential of SweFN++, both in relation to ICALL and to other types
of resources and descriptive databases, like corpora, constructicons
and framenets.
How register-specific is probabilistic grammatical knowledge?
Authors: Engel Alexandra , Grafmiller Jason , Rosseel Laura , Szmrecsanyi Benedikt , Van de Velde Freek
Published: November 2021

While there is preliminary evidence about the importance of register in linguistic choice-making processes,
systematic studies focusing on the interaction between register and language-internal constraints are lacking in variationist
linguistics. This contribution sketches an ongoing project in which two well-understood grammatical alternations (dative
alternation and future marker alternation) are analysed with variationist methods, focusing on the role of register defined at
the intersection of mode (spoken vs written) and formality (formal vs informal). Probabilistic corpus models will be
complemented with rating experiments to investigate to what extent they correlate with participants’ ratings, and to
illustrate the importance of methodological diversity in investigating usage-based theories of grammar. We present corpus
results of a case study on the dative alternation with give.
Dual-mode of topological rainbow in gradual photonic heterostructures
Authors: Li Ming Xing , Wang Yue Ke , Lu Meng Jia , Sang Tian
Published: November 2021

In this letter, a method to realize topological rainbow trapping is presented, which is composed of gradual trivial-nontrivial-trivial heterostructures based on two-dimensional photonic crystals with C-4 symmetry. In the proposed sandwiched structure, the two coupled topological edge states with different frequencies are separated and trapped in different positions, due to group velocity of near to zero. We have achieved the dual-mode of topological rainbow in one structure, and the dual-mode of topological rainbow under one mode excitation is also realized by using a simple bend design. The immunity to defects is also investigated and it is found our slowing light system has strong robustness. Finite element method simulation results verify our idea, and our work opens up a new approach for frequency routing of topological photonic states.
Performance analysis and validation of precision multisatellite RF measurement scheme for microsatellite formations
Authors: Lin Chen , Jin Xiaojun , Mo Shiming , Hou Cong , Zhang Wei , Xu Zhaobin , Jin Zhonghe
Published: November 2021

Almost all existing studies on inter-satellite radio-frequency (RF) measurement have focused on two-satellite formations. Although some frequency division multiple access and code division multiple access multisatellite RF measurement schemes have been proposed, their poor scalability does not satisfy the inter-satellite measurement requirements of multisatellite formations, especially large-scale formations. Two-way ranging (TWR), which is based on a time division mechanism, is an effective solution that has been used for inter-satellite links in the global positioning system and Beidou navigation constellations. However, the high measurement accuracy achieved with TWR in these navigation constellations is heavily reliant on high-performance atomic clocks and the assistance of navigation ephemeris, which are not available on microsatellite platforms. This work focuses on a scalable multisatellite measurement scheme that adopts a distributed broadcast-based time division multiple access mechanism as the media access control layer and uses an asymmetric double-side TWR method as the physical layer. The measurement performance of the proposed scheme is evaluated through in-depth theoretical modeling, simulation verification, and experimental validation, along with a comprehensive comparison with the conventional TWR method. The experimental results show that centimeter-level measurement accuracy can be achieved with the proposed scheme when only a common miniaturized frequency source is used. This accuracy level is two orders of magnitude better than that of the TWR method, and thus satisfies the application requirements of general large-scale microsatellite formations.
A retrospective analysis of the impact of a hospital pharmacist-led procalcitonin protocol
Authors: Cowey Carrolyn K , Wilson Erica
Published: November 2021

Purpose

Procalcitonin is a precursor hormone to calcitonin that increases in response to systemic inflammation, especially of bacterial origin, and is otherwise undetectable in healthy states. Studies have shown that following effective antimicrobial treatment, procalcitonin levels steadily decline. To be utilized however, procalcitonin levels determinations must be ordered at specific times during a patient’s antimicrobial treatment. A retrospective medication-use evaluation of patients was performed at Medical Center Hospital and showed that in 70% of patients, initial procalcitonin levels were ordered inappropriately and procalcitonin levels were trended inconsistently during antibiotic treatment.

Methods

A pharmacist-led procalcitonin protocol was developed and presented to medical staff committees for approval. Data was collected from patients presenting with suspected or confirmed sepsis or lower respiratory tract infections for whom procalcitonin levels were utilized. Patient outcomes before and after protocol implementation were compared.

Results

A total of 400 patients were included in the study. The primary outcome of appropriate ordering of initial procalcitonin levels was improved in the postprotocol group relative to the preprotocol group (28% of patients [n = 56] vs 72% of patients [n = 144]; P < 0.001). Patients in the postprotocol group had a procalcitonin level checked at discontinuation more frequently (8% [n = 16] vs 37% [n = 74], P < 0.001) and had a higher rate of appropriate discontinuation of antibiotics (12% [n = 21] vs 46% [n = 77]; P < 0.001). The postprotocol group also had fewer mean days of antibiotic therapy (9.17 vs 6.01; P < 0.001).

Conclusion

Studies have shown the usefulness of procalcitonin levels for antimicrobial stewardship, but for procalcitonin testing to be properly utilized it must be ordered at the correct times during the patient’s therapy. The implementation of a hospital-wide pharmacist-led protocol resulted in an increase in appropriate ordering of baseline procalcitonin levels.
Deciphering the core elements around haemodialysis therapy
Authors: Bowry Sudhir K , Ortiz Alberto Arduan , Maddux Frank W
Published: November 2021

The projected future demand for renal replacement therapies for patients with end-stage renal failure requires preparedness at different levels. The deliberations focus predominantly on the disproportionately high financial burden of care for patients on routine dialysis therapy compared with other chronic conditions. However, even today there are concerns regarding the shortage of healthcare workers in the field of nephrology. A substantial increase in trained healthcare professionals is needed for the future delivery and care of patients requiring haemodialysis (HD) that 89% of patients on dialysis receive; a sustainable health workforce is the cornerstone of any healthcare system. The multimorbid nature of chronic kidney disease as well as the complexity—especially the technical aspects—of HD are deterrents for pursuing nephrology as a career. An educational platform that critically examines the essential issues and components of HD therapy was thus considered appropriate to create or renew interest in nephrology. By providing broader and newer perspectives of some of the core principles around which HD evolves, with this set of articles we seek to facilitate a better appreciation of HD. We believe that such a reappraisal of either poorly understood or ill-defined principles, including usage of terminology that is imprecise, will help facilitate a better understanding of the functioning principles of HD.
Miniseries 1—Part I: the Development of the atrioventricular conduction axis
Authors: Hikspoors Jill P J M , Macías Yolanda , Tretter Justin T , Anderson Robert H , Lamers Wouter H , Mohun Timothy J , Sánchez-Quintana Damián , Farré Jerónimo , Back Sternick Eduardo
Published: November 2021

Despite years of research, many details of the formation of the atrioventricular conduction axis remain uncertain. In this study, we aimed to clarify the situation. We studied three-dimensional reconstructions of serial histological sections and episcopic datasets of human embryos, supplementing these findings with assessment of material housed at the Human Developmental Biological Resource. We also examined serially sectioned human foetal hearts between 10 and 30 weeks of gestation. The conduction axis originates from the primary interventricular ring, which is initially at right angles to the plane of the atrioventricular canal, with which it co-localizes in the lesser curvature of the heart loop. With rightward expansion of the atrioventricular canal, the primary ring bends rightward, encircling the newly forming right atrioventricular junction. Subsequent to remodelling of the outflow tract, part of the primary ring remains localized on the crest of the muscular ventricular septum. By 7 weeks, its atrioventricular part has extended perpendicular to the septal parts. The atrioventricular node is formed at the inferior transition between the ventricular and atrial parts, with the transition itself marking the site of the penetrating atrioventricular bundle. Only subsequent to muscularization of the true second atrial septum does it become possible to recognize the definitive node. The conversion of the developmental arrangement into the definitive situation as seen postnatally requires additional remodelling in the first month of foetal development, concomitant with formation of the inferior pyramidal space and the infero-septal recess of the subaortic outflow tract.
Subaqueous fault scarps of the North Anatolian Fault in the Gulf of Saros (NE Aegean); where is the western limit of the 1912 Mürefte-Şarköy earthquake rupture?
Authors: Aksoy M Ersen , Meghraoui Mustapha , Polonia Alina , Çağatay M Namık , Yavuzoğlu Aslı Zeynep , Önder Şebnem , Ülgen Umut B , Gasperini Luca
Published: November 2021

The westernmost segment of the North Anatolian fault in NW Turkey lies mostly offshore, in the Sea of Marmara and the Gulf of Saros (NE Aegean), respectively to the E and W of a 45 km inland central portion. The 9 August 1912 Mürefte-Şarköy (Ms 7.4) and 13 September 1912 (Ms 6.8) earthquakes occurred along this segment. To date, the segment was studied mostly onshore although estimated magnitude and location suggest an offshore extension. Recent studies show the eastern rupture extension in the Sea of Marmara, while its western counterpart in the Gulf of Saros remains less documented. Here we use new observations from high-resolution marine geophysical data (multibeam bathymetry, side-scan-sonar, and seismic reflection profiles), to constrain the offshore 1912 ruptures in the Gulf of Saros. Detailed mapping of the subaqueous fine-scale morphology and structure of the fault provides a new insight for the western limit of the two 1912 surface ruptures. Distribution of fresh scarps, 3-D structural reconstructions, the complexity of fault segments, and the recent seismicity, altogether suggest that the western termination of the 1912 rupture(s) ends 37 km offshore in the Gulf of Saros. Following the 1999 Kocaeli earthquake, in the eastern Sea of Marmara, the unruptured segment length between the 1999 and 1912 ruptures became a critical issue, because of its implication for future earthquakes in the so-called Marmara seismic gap. If a 150–160 km total rupture length for the two 1912 earthquakes is assumed, a western rupture termination point at the inner Saros basin margin means that the eastern extension of the 9 August earthquake rupture reached the Central Marmara Basin. This outcome necessarily has implications for the seismic hazard in the Marmara coastal area that includes the Istanbul metropolitan area.
Joint inversion of gravity, magnetotelluric and seismic data using the alternating direction method of multipliers
Authors: Liao Chen , Hu Xiangyun , Zhang Shihui , Li Xuewen , Yin Quanzeng , Zhang Zhao , Zhang Longfei
Published: November 2021

Joint inversion for the same or different geophysical parameters is proved to be an effective technique for obtaining high-resolution solutions. Thus, comprehensive geophysical interpretation based on joint inversion has been widely concerned and applied in recent years. To realize joint inversion conveniently and efficiently, we proposed a new inversion strategy based on the alternating direction method of multipliers. In this regard, three optimization algorithms were presented respectively to attain the joint inversion of body wave traveltime and surface wave dispersion data, to obtain the joint inversion of magnetotelluric and seismic data with cross-gradient constraints, and to acquire gravity constrained inversion. A complex model with inconsistent structures in terms of resistivity, velocity and density was designed to evaluate the accuracy and effectiveness of the multiparameter joint inversion algorithms. In our joint inversion processes, each method was optimized independently and the jointly inverted results were significantly more accurate than those of separate inversions. Finally, we applied the algorithms to the field data involving gravity anomaly data, magnetotelluric data and Rayleigh wave dispersion data. The reliable underground structure was achieved by the joint interpretation of density, resistivity and velocity profiles, which verified the practicality of the inversion strategy in the actual data.
Drivers of variation in crustacean zooplankton production rates differ across regions off the west coast of Vancouver Island and in the subarctic NE Pacific
Authors: Venello Theresa A , Sastri Akash R , Suchy Karyn D , Galbraith Moira D , Dower John F
Published: November 2021

The subarctic NE Pacific is comprised of several oceanographic regimes, in which regional variability in sea surface temperature (SST), satellite chlorophyll a, and crustacean zooplankton biomass influence the production rates of crustacean zooplankton. Traditional methods for estimating zooplankton production rates are labour/time intensive and restricted to select copepod species. A practical field alternative is the ‘chitobiase method’, which yields community-level biomass production rates (BPR) analogous to traditional moulting rate methods. BPR was measured along the west coast of Vancouver Island and in the subarctic NE Pacific during 2005, 2009–2011, and 2015–2018. Generalized additive modelling identified SST and the developing crustacean zooplankton biomass as key drivers of BPR variability. BPR varied positively with the proportion of developing copepod biomass relative to that of non-copepod crustacean zooplankton biomass. Our analysis indicates that BPR variation is associated with zooplankton community composition, but that high zooplankton biomass is not necessarily predictive of high BPR. Specifically, higher BPR is associated with a higher relative biomass of large-bodied, cold-water indicator species, and a lower biomass of non-copepod crustaceans.
Defining value in health care: a scoping review of the literature
Authors: Landon Susan n , Padikkala Jane , Horwitz Leora i
Published: November 2021

Background

As health-care spending rises internationally, policymakers have increasingly begun to look to improve health-care value. However, the precise definition of health-care value remains ambiguous.

Methods

We conducted a scoping review of the literature to understand how value has been defined in the context of health care. We searched PubMed, Embase, Google Scholar, PolicyFile and Scopus between February and March 2020 to identify articles eligible for inclusion. Publications that defined value (including high or low value) using an element of cost and an element of outcomes were included in this review. No restrictions were placed on the date of publication. Articles were limited to those published in English.

Results

Out of 1750 publications screened, 46 met inclusion criteria. Among the 46 included articles, 22 focused on overall value, 19 on low value and 5 on high value. We developed a framework to categorize definitions based on three core domains: components, perspective and scope. Differences across these three domains contributed to significant variations in definitions of value.

Conclusions

How value is defined has the potential to influence measurement and intervention strategies in meaningful ways. To effectively improve value in health-care systems, we must understand what is meant by value and the merits of different definitions.
Playing with Religion: Delight at the Border between Epistemological Worlds
Authors: Dunn Mary
Published: November 2021

This article builds on conversations that began here in the Journal of the American Academy of Religion in 2019 on Jonathan Z. Smith’s legacy to the study of religion. Specifically, in this article I take up and elaborate on Heather Blair’s tentative proposal for thinking about religious studies as a kind of play. Beginning with Blair and engaging with the work of Sam Gill, Tyler Roberts, Robert Orsi, and others, I put forward a strong argument for adopting a playful approach to the study of religion. A programmatic alternative to reading religion against the grain and between the lines, a ludic approach to religious studies enables the scholar to engage with religion in ways that fruitfully combine at least provisional commitment to its rules with ironic disavowal, inviting the scholar to play between the incommensurate epistemologies of enchanted religious worlds, on the one hand, and the disenchanted modern academy, on the other. It is here, I argue, in this frictive space between these mutually exclusive and logically incompatible positions that religious studies finds its niche (or should), trafficking—and delighting—in the creative insights generated by the oscillation between fit and no-fit.
Dark Energy Survey Year 3 results: galaxy–halo connection from galaxy–galaxy lensing
Authors: Zacharegkas G , Chang C , Prat J , Pandey S , Ferrero I , Blazek J , Jain B , Crocce M , DeRose J , Palmese A , Seitz S , Sheldon E , Hartley W G , Wechsler R H , Dodelson S , Fosalba P , Krause E , Park Y , Sánchez C , Alarcon A , Amon A , Bechtol K , Becker M R , Bernstein G M , Campos A , Carnero Rosell A , Carrasco Kind M , Cawthon R , Chen R , Choi A , Cordero J , Davis C , Diehl H T , Doux C , Drlica-Wagner A , Eckert K , Elvin-Poole J , Everett S , Ferté A , Gatti M , Giannini G , Gruen D , Gruendl R A , Harrison I , Herner K , Huff E M , Jarvis M , Kuropatkin N , Leget P-F , MacCrann N , McCullough J , Myles J , Navarro-Alsina A , Porredon A , Raveri M , Rollins R P , Roodman A , Ross A J , Rykoff E S , Secco L F , Sevilla-Noarbe I , Shin T , Troxel M A , Tutusaus I , Varga T N , Yanny B , Yin B , Zhang Y , Zuntz J , Abbott T M C , Aguena M , Allam S , Andrade-Oliveira F , Annis J , Bacon D , Bertin E , Brooks D , Burke D L , Carretero J , Castander F J , Costanzi M , da Costa L N , Pereira M E S , Desai S , Dietrich J P , Doel P , Evrard A E , Flaugher B , Frieman J , García-Bellido J , Gaztanaga E , Gschwend J , Gutierrez G , Hinton S R , Hollowood D L , Honscheid K , Hoyle B , James D J , Kuehn K , Lima M , Maia M A G , Marshall J L , Melchior P , Menanteau F , Miquel R , Muir J , Ogando R L C , Paz-Chinchón F , Pieres A , Sanchez E , Serrano S , Smith M , Suchyta E , Tarle G , Thomas D , To C , Wilkinson R D , (DES Collaboration)
Published: November 2021

Galaxy–galaxy lensing is a powerful probe of the connection between galaxies and their host dark matter haloes, which is important both for galaxy evolution and cosmology. We extend the measurement and modelling of the galaxy–galaxy lensing signal in the recent Dark Energy Survey Year 3 cosmology analysis to the highly non-linear scales (∼100 kpc). This extension enables us to study the galaxy–halo connection via a Halo Occupation Distribution (HOD) framework for the two lens samples used in the cosmology analysis: a luminous red galaxy sample (redmagic) and a magnitude-limited galaxy sample (maglim). We find that redmagic (maglim) galaxies typically live in dark matter haloes of mass log10(Mh/M⊙) ≈ 13.7 which is roughly constant over redshift (13.3−13.5 depending on redshift). We constrain these masses to ${\sim}15{{\ \rm per\ cent}}$, approximately 1.5 times improvement over the previous work. We also constrain the linear galaxy bias more than five times better than what is inferred by the cosmological scales only. We find the satellite fraction for redmagic (maglim) to be ∼0.1−0.2 (0.1−0.3) with no clear trend in redshift. Our constraints on these halo properties are broadly consistent with other available estimates from previous work, large-scale constraints, and simulations. The framework built in this paper will be used for future HOD studies with other galaxy samples and extensions for cosmological analyses.
Gaia EDR3 bright star parallax zero-point using stellar clusters
Authors: Flynn C , Sekhri R , Venville T , Dixon M , Duffy A , Mould J , Taylor E N
Published: November 2021

We examine the zero-point of parallaxes in the Gaia EDR3 (Early Data Release 3, Gaia Collaboration (2021a)), using stars in open and globular clusters. Our aim is to check for zero-point systematics between bright stars G < 12 (which includes some important distance scale calibrators) and faint stars G > 14, for which the parallax scale has been very well tied to the extragalactic frame using active galactic nuclei and quasars (AGN/QSOs) observed by Gaia (Lindegren et al. 2021). Cluster stars are distinguished from field stars using conservative spatial and proper motion cuts. The median parallax cluster stars fainter the G = 14 are compared with the parallaxes of bright stars (G < 14) to search for zero-point systematics. We confirm that the Lindegren et al. (2021) parallax corrections bring cluster stars into very good agreement over a wide range of magnitude and colour. We find small residual colour-dependent offsets for the bright stars (G < 11). Specifically, we find a median parallax offset of $\approx 10\, \mu$as between the reddest stars (BP − RP > 1) compared to those stars with colours similar to the AGN/QSOs (0.5 < BP − RP < 1) that serve as the primary zero-point calibrators for EDR3. These findings are similar to those found in other recent independent checks of the zero-point scale, and have significant implications for calibrating the extragalactic distance scale to stars in the Milky Way.
Evolution towards energy equipartition in star clusters: effects of the tidal field, primordial binaries, and internal velocity anisotropy
Authors: Pavlík Václav , Vesperini Enrico
Published: November 2021

This paper is the second in a series investigating the evolution of star clusters towards energy equipartition (EEP). Here, we focus on the effects of the external tidal field of the host galaxy, initial anisotropy in the velocity distribution, and primordial binary star population. The results of our N-body simulations show that regardless of the strength of the tidal field or the fraction of primordial binaries: (i) the evolution towards EEP in the intermediate and outer regions of initially anisotropic systems is more rapid than for isotropic systems; (ii) this evolution also proceeds at different rates for the tangential and radial components of the velocity dispersion; and (iii) the outer regions of the initially isotropic systems show a tendency to evolve towards a state of ‘inverted’ EEP in which low-mass stars have smaller velocity dispersion than high-mass stars. We also find that the clusters with primordial binaries stay even farther from EEP than systems containing only single stars. Finally, we show that all these results also hold when the degree of EEP is calculated using quantities measured in projection as it is done in observational studies, and that our findings could be tested with current and upcoming observational data.
Hiding in plain sight: observing planet-starspot crossings with the James Webb Space Telescope
Authors: Bruno Giovanni , Lewis Nikole K , Valenti Jeff A , Pagano Isabella , Wilson Tom J , Schlawin Everett , Lothringer Joshua , Lanza Antonino F , Fraine Jonathan , Scandariato Gaetano , Micela Giuseppina , Cracchiolo Gianluca
Published: November 2021

Transiting exoplanets orbiting active stars frequently occult starspots and faculae on the visible stellar disc. Such occultations are often rejected from spectrophotometric transits, as it is assumed they do not contain relevant information for the study of exoplanet atmospheres. However, they can provide useful constraints to retrieve the temperature of active features and their effect on transmission spectra. We analyse the capabilities of the James Webb Space Telescope in the determination of the spectra of occulted starspots, despite its lack of optical wavelength instruments on board. Focusing on K and M spectral types, we simulate starspots with different temperatures and in different locations of the stellar disc, and find that starspot temperatures can be determined to within a few hundred kelvins using NIRSpec/Prism and the proposed NIRCam/F150W2+F322W2’s broad wavelength capabilities. Our results are particularly promising in the case of K and M dwarfs of mag$_K \lesssim 12.5$ with large temperature contrasts.
Optimal 1D Ly α forest power spectrum estimation – II. KODIAQ, SQUAD, and XQ-100
Authors: Karaçaylı Naim Göksel , Padmanabhan Nikhil , Font-Ribera Andreu , Iršič Vid , Walther Michael , Brooks David , Gaztañaga Enrique , Kehoe Robert , Levi Michael , Ntelis Pierros , Palanque-Delabrouille Nathalie , Tarlé Gregory
Published: November 2021

We measure the 1D Ly α power spectrum P1D from Keck Observatory Database of Ionized Absorption toward Quasars (KODIAQ), The Spectral Quasar Absorption Database (SQUAD), and XQ-100 quasars using the optimal quadratic estimator. We combine KODIAQ and SQUAD at the spectrum level, but perform a separate XQ-100 estimation to control its large resolution corrections in check. Our final analysis measures P1D at scales k < 0.1 s km−1 between redshifts $z$ = 2.0–4.6 using 538 quasars. This sample provides the largest number of high-resolution, high-S/N observations; and combined with the power of optimal estimator it provides exceptional precision at small scales. These small-scale modes (k ≳ 0.02 s km−1), unavailable in Sloan Digital Sky Survey and Dark Energy Spectroscopic Instrument analyses, are sensitive to the thermal state and reionization history of the intergalactic medium, as well as the nature of dark matter. As an example, a simple Fisher forecast analysis estimates that our results can improve small-scale cut-off sensitivity by more than a factor of 2.
The role of thermal and non-thermal processes in the ISM of the Magellanic Clouds
Authors: Hassani H , Tabatabaei F , Hughes A , Chastenet J , McLeod A F , Schinnerer E , Nasiri S
Published: November 2021

Radio continuum emission is a dust-unbiased tracer of both thermal and non-thermal processes in the interstellar medium. We present new maps of the free–free and synchrotron emission in the Magellanic Clouds (MCs) at 0.166, 1.4, and 4.8 GHz with no prior assumption about the radio non-thermal spectrum. The maps were constructed using a de-reddened H α map as a template for the thermal radio emission, which we subtract from maps of the total radio continuum emission. To de-redden the H α emission, it is important to know the fraction of dust surface density that attenuates the H α emission along the line of sight, fd. This fraction is obtained by comparing the dust opacity obtained through the infrared emission spectrum and the Balmer decrement method. In star-forming regions, the median fd is about 0.1, which is lower than that in diffuse regions by a factor of three. We obtain a global thermal radio fraction, fth, of 30 per cent (35 per cent) in the LMC (SMC) at 1.4 GHz. Furthermore, we present maps of the equipartition magnetic field strength with average values of $\simeq \, 10.1\, \mu$G in the LMC and $\simeq \, 5.5\, \mu$G in the SMC. The magnetic field is proportional to the star-formation rate to the power of 0.24 and 0.20 for the LMC and SMC, respectively. This study shows that non-thermal processes control the interstellar medium in the MCs.
Are blazars above the blazar sequence a significant source of IceCube neutrinos?
Authors: Savard Katherine , Ruan John J , Haggard Daryl
Published: November 2021

The recent association of two flaring blazars (TXS 0506+056 and 3HSP J095507.9+355101) with IceCube neutrinos strongly suggests that blazars are at least one source of high-energy neutrinos. A peculiar characteristic of these two blazars is that they both appear to lie above the well-known blazar sequence, and they move further above the blazar sequence during the neutrino emission. Although the reason for this peculiarity is unclear, it may indicate a link between blazar SED properties and neutrino emission. Here, we test whether blazars lying above the blazar sequence are overrepresented in IceCube neutrino error regions. We spatially cross-match IceCube error regions with a sample of γ-ray blazars from the Fermi-LAT 4LAC catalogue, as a function of the blazars’ distance in synchrotron peak frequency above the blazar sequence. We do not find a statistically significant excess of counterparts, and thus conclude that the current data cannot confirm that the sources above the blazar sequence are a significant source of IceCube neutrinos. However, we show that the inclusion of more recently detected IceCube events increases the likelihood of an excess of blazars above the blazar sequence, and suggest that this excess may reach statistical significance in the future as the sample of IceCube neutrino detections increases.
Uncertainty-aware learning for improvements in image quality of the Canada–France–Hawaii Telescope
Authors: Gilda Sankalp , Draper Stark C , Fabbro Sébastien , Mahoney William , Prunet Simon , Withington Kanoa , Wilson Matthew , Ting Yuan-Sen , Sheinis Andrew
Published: November 2021

We leverage state-of-the-art machine learning methods and a decade’s worth of archival data from Canada–France–Hawaii Telescope (CFHT) to predict observatory image quality (IQ) from environmental conditions and observatory operating parameters. Specifically, we develop accurate and interpretable models of the complex dependence between data features and observed IQ for CFHT’s wide-field camera, MegaCam. Our contributions are several-fold. First, we collect, collate, and reprocess several disparate data sets gathered by CFHT scientists. Second, we predict probability distribution functions of IQ and achieve a mean absolute error of ∼0.07 arcsec for the predicted medians. Third, we explore the data-driven actuation of the 12 dome ‘vents’ installed in 2013–14 to accelerate the flushing of hot air from the dome. We leverage epistemic and aleatoric uncertainties in conjunction with probabilistic generative modelling to identify candidate vent adjustments that are in-distribution (ID); for the optimal configuration for each ID sample, we predict the reduction in required observing time to achieve a fixed signal-to-noise ratio. On average, the reduction is $\sim 12{{\ \rm per\ cent}}$. Finally, we rank input features by their Shapley values to identify the most predictive variables for each observation. Our long-term goal is to construct reliable and real-time models that can forecast optimal observatory operating parameters to optimize IQ. We can then feed such forecasts into scheduling protocols and predictive maintenance routines. We anticipate that such approaches will become standard in automating observatory operations and maintenance by the time CFHT’s successor, the Maunakea Spectroscopic Explorer, is installed in the next decade.
The mean free path approximation and stellar collisions in star clusters: numerical exploration of the analytic rates and the role of perturbations on binary star mergers
Authors: Reinoso Bastián , Leigh Nathan W C , Barrera-Retamal Carlos M , Schleicher Dominik , Klessen Ralf S , Stutz Amelia M
Published: November 2021

In this paper, we compute predictions for the number of stellar collisions derived from analytic models based on the mean free path (MFP) approximation and compare them to the results of N-body simulations. Our goal is to identify the cluster conditions under which the MFP approximation remains valid. Adopting a range of particle numbers (100 ≤ N ≤ 5000) and different combinations of particle masses and radii, we explore three different channels leading to stellar collisions, all of which are expected to occur in realistic stellar environments. At high densities, binaries form from isolated three-body interactions of single stars. Hence, we consider collisions between single stars and collisions involving binary stars, after they form in our simulations. For the latter, we consider two channels for mergers, namely direct stellar collisions during chaotic single–binary interactions and perturbation-driven mergers of binaries due to random walks in eccentricity approaching unity. In the densest systems considered here, a very massive object is formed at the cluster centre, causing local stellar orbits to become increasingly Keplerian and the assumptions going into our analytic model to break down. Before reaching this limit, we obtain excellent agreement between our theoretical predictions and the simulations: The analytic rates are typically accurate to within one standard deviation for the entire parameter space considered here, but the agreement is best for short integration times. Our results have direct implications for blue straggler formation in dense star clusters, and stellar mergers in galactic nuclei hosting massive black holes.
Probing Transit Timing Variations of three hot Jupiters: HATP-36b, HATP-56b, and WASP-52b
Authors: Sonbas E , Karaman N , Özdönmez A , Er H , Dhuga K S , Göğüş E , Nasiroglu I , Zejmo M
Published: November 2021

We report the results of new transit observations for the three hot Jupiter-like planets, HATP-36b, HATP-56b, and WASP-52b, respectively. Transit timing variations (TTVs) are presented for these systems based on observations that span the period 2016–2020. The data were collected with the 0.6-m telescope at Adiyaman University (ADYU60, Turkey) and the 1.0 m telescope at TÜBİTAK National Observatory (TUG, Turkey). Global fits were performed to the combined light curves for each system along with the corresponding radial velocity (RV) data taken from the literature. The extracted parameters (for all three systems) are found to be consistent with the values from previous studies. Through fits to the combined mid-transit times data from our observations and the data available in the literature, an updated linear ephemeris is obtained for each system. Although a number of potential outliers are noted in the respective O-C diagrams, the majority of the data are consistent within the 3σ confidence level implying a lack of convincing evidence for the existence of additional objects in the systems studied.