bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiplicadores Locales de Empleo en las Ciudades de México: contribuciones del empleo manufacturero, comerciable y creativo
Authors: Valdivia Marcos
Published: October 2024

Este trabajo presenta estimaciones de multiplicadores locales de empleo en 386 ciudades y en 33 ciudades capitales de México para los periodos 2010-2020 y 2006-2018 respectivamente. Además de la clasificación tradicional que distingue entre empleo manufacturero y no manufacturero, se considera una clasificación alternativa de bienes comerciables basada en índices de concentración laboral a nivel de rama. El estudio estima multiplicadores significativos del empleo manufacturero que se ubican en el rango superior a los hallados en otras regiones del mundo. En contraste, la clasificación alternativa genera multiplicadores de magnitud inferior que son más consistentes a los estimados para otros países. Este estudio demuestra que estos últimos son más adecuados para entender este fenómeno en México. La investigación a su vez documenta que los multiplicadores de empleo asociados a actividades creativas son superiores a los estimados en el conjunto del empleo manufacturero y comerciable, y similares a los desarrollados por el empleo tecnológico.
El impacto de diferentes tipos de delitos en la recuperación del precio de la vivienda en España (2015-2019): un análisis empírico a nivel de ciudades
Authors: Torres-tellez Jonathan
Published: October 2024

La crisis económica de 2008 produjo en España una fuerte corrección del precio de la vivienda que no mostró signos de recuperación hasta principios de 2014. Este artículo analiza para el caso español cómo inﬂuyeron diferentes delitos en la recuperación del precio de la vivienda entre 2015-2019. Se emplea un panel de datos con efectos ﬁjos para 119 ciudades españolas. Los resultados muestran que la vivienda se devalúa ante un incremento de la delincuencia, aunque se reﬂeja entre uno y dos años después (-0,2%). También se conﬁrma que los delitos contra el patrimonio producen un mayor impacto negativo en el precio, especialmente el robo con violencia (-1,3%) y el robo con fuerza en domicilios (0,8%).
The eﬀect of internal migration on regional growth in Italy: a dynamic spatial panel data analysis
Authors: Centofanti Francesca , Basile Roberto , Licari Francesca , Pitari Jacopo
Published: October 2024

This study assesses the eﬀect of internal migration on regional growth in Italy at the NUTS-3 level over the period 2002-2019. The composition of the internal migration ﬂows of the working-age population in Italy during the sample period appears substantially heterogeneous in nationality and labor skills. The analysis considers this heterogeneity, estimating various speciﬁcations of the dynamic spatial model and controlling for the endogeneity of migration variables through a control function approach. e evidence suggests that the internal migration of Italian citizens has a positive direct and spillover impact on regional growth, slowing down the convergence process. On the contrary, there is no evidence of a signiﬁcant eﬀect of internal migration of foreign citizens. Taking the skill composition of internal movements of Italian citizens into account, the adverse impact on convergence is magniﬁed, thus corroborating the skill-selective hypothesis. Finally, the diverging impact of internal migration increases with the distance of migration ﬂows.
Iniciativa público-comunitaria de cuidados en el País Vasco: una experiencia intergeneracional entre infancia y mayores en situación de vulnerabilidad
Authors: Sagastizabal Marina , Eiguren Amaia
Published: October 2024

La sociedad actualmente es más longeva y diversa. Ante el aumento de las necesidades de cuidados urge generar nuevas respuestas sociales. Las experiencias intergeneracionales pueden ayudar en este camino, a través de la construcción de espacios comunitarios que fortalezcan la dimensión relacional del cuidado y la cohesión social. La experiencia intergeneracional público-comunitaria analizada en este artículo genera redes de cuidado mutuo entre personas mayores e infancia, ambas en situación de vulnerabilidad. Partiendo de una metodología cualitativa, se realiza un estudio de caso centrado en Vitoria-Gasteiz para analizar los beneﬁcios y limitaciones de esta experiencia. Las conclusiones apuntan a la necesidad de reforzar y dar continuidad a este tipo de experiencias, fomentando una sociedad más inclusiva para todas las edades.
Unveiling the pandemic's impact: Did COVID-19 drive business failures? A Cutting-Edge Analysis with Spatial Autoregressive Modelling
Authors: Garnés Galindo David , Ruiz-Marín Manuel , Maté-Sánchez-Val María Luz
Published: October 2024

The objective of this study is to estimate the impact of Covid-19 on business behavior and its spatial eﬀect among companies. Four speciﬁcations have been developed to analyze the pandemic's inﬂuence on key variables determining business behavior: liquidity, indebtedness, proﬁtability, and eﬃciency. This study has focused on the province of Barcelona, Spain, from which a database of failed and non-failed companies has been compiled, both before and after the pandemic. The models have been estimated using the spatial Seemingly Unrelated Regressions (SUR) methodology, and each equation was estimated following a spatial Diﬀerences-in-Diﬀerences model. The results conﬁrm that the emergence of Covid-19 has had a signiﬁcant impact on companies' ﬁnancial ratios, worsening their positions in terms of liquidity, indebtedness, and eﬃciency, with the existence of a spatial contagion pattern.
SDSS. IV. MaNGA: The Impact of the Acquisition of Gas with Opposite Angular Momentum on the Evolution of Galaxies
Authors: Beom Minje , Walterbos René A. M. , Bizyaev Dmitry
Published: October 2024

A gaseous counterrotating galaxy is a galaxy containing a gas component with opposite angular momentum to the main stellar disk. The counterrotating gas provides direct evidence for the accretion of external material, a key aspect in hierarchical galaxy evolution. We identified 303 gaseous counterrotators out of 9992 galaxies in MaNGA. The majority of the counterrotators are early types. This implies their formation is highly correlated with early-type galaxies, although it is still difficult to know if one leads to the other. To disentangle which of the galaxy characteristics within a morphological class were changed by the accretion of counterrotating gas, we carefully selected a comparison sample with similar fundamental galactic properties but corotation in gas. This comparison shows that gaseous counterrotation correlates with weak rotation in the stellar component, the high central concentration of star-forming regions, if present, and a higher fraction of central low ionization emission regions (cLIER) galaxies. The light distributions of the stellar components, dust and H i content (both low), and overall suppressed star formation rates are similar for both samples and seem typical for the morphological class. We claim that elliptical and about half of the lenticular counterrotators, those with weak rotation in the stellar component in the outskirts and central regions, likely have a major merger origin for the gas acquisition, and the other half of lenticulars, with stronger stellar rotation, may have a minor merger or pure gas accretion origin.
Digging into the Interior of Hot Cores with ALMA (DIHCA). IV. Fragmentation in High-mass Star-forming Clumps
Authors: Ishihara Kousuke , Sanhueza Patricio , Nakamura Fumitaka , Saito Masao , Chen Huei-Ru Vivien , Li Shanghuo , Olguin Fernando , Taniguchi Kotomi , Morii Kaho , Lu Xing , Luo Qiu-yi , Sakai Takeshi , Zhang Qizhou
Published: October 2024

Fragmentation contributes to the formation and evolution of stars. Observationally, high-mass stars are known to form multiple-star systems, preferentially in cluster environments. Theoretically, Jeans instability has been suggested to determine characteristic fragmentation scales, and thermal or turbulent motion in the parental gas clump mainly contributes to the instability. To search for such a characteristic fragmentation scale, we have analyzed Atacama Large Millimeter/submillimeter Array (ALMA) 1.33 mm continuum observations toward 30 high-mass star-forming clumps taken by the Digging into the Interior of Hot Cores with ALMA survey. We have identified 573 cores using the dendrogram algorithm and measured the separation of cores by using the Minimum Spanning Tree technique. The core separation corrected by projection effects has a distribution peaked around 5800 au. In order to remove biases produced by different distances and sensitivities, we further smooth the images to a common physical scale and perform completeness tests. Our careful analysis finds a characteristic fragmentation scale of ∼7000 au, comparable to the thermal Jeans length of the clumps. We conclude that thermal Jeans fragmentation plays a dominant role in determining the clump fragmentation in high-mass star-forming regions, without the need to invoke turbulent Jeans fragmentation.
Atmospheric Response for MeV γ Rays Observed with Balloon-borne Detectors
Authors: Karwin Christopher M. , Kierans Carolyn , Shih Albert Y. , Martinez Castellanos Israel , Lowell Alex , Siegert Thomas , Roberts Jarred , Gallego Savitri , Laviron Adrien , Zoglauer Andreas , Tomsick John A. , Boggs Steven E. ,   for the COSI Collaboration
Published: October 2024

The atmospheric response for MeV γ rays (∼0.1–10 MeV) can be characterized in terms of two observed components. The first component is due to photons that reach the detector without scattering. The second component is due to photons that reach the detector after scattering one or more times. While the former can be determined in a straightforward manner, the latter is much more complex to quantify, as it requires tracking the transport of all source photons that are incident on Earth’s atmosphere. The scattered component can cause a significant energy-dependent distortion in the measured spectrum, which is important to account for when making balloon-borne observations. In this work, we simulate the full response for γ-ray transport in the atmosphere. We find that the scattered component becomes increasingly more significant toward lower energies, and at 0.1 MeV, it may increase the measured flux by as much as a factor of ∼2–4, depending on the photon index and off-axis angle of the source. This is particularly important for diffuse sources, whereas the effect from scattering can be significantly reduced for point sources observed with an imaging telescope.
Multistructured Accretion Flow of Sgr A*. II. Signatures of a Cool Accretion Disk in Hydrodynamic Simulations of Stellar Winds
Authors: Balakrishnan Mayura , Russell Christopher M. P. , Corrales Lia , Calderón Diego , Cuadra Jorge , Haggard Daryl , Markoff Sera , Neilsen Joey , Nowak Michael , Wang Q. Daniel , Baganoff Frederick
Published: October 2024

Hydrodynamic simulations of the stellar winds from Wolf–Rayet stars within the Galactic center can provide predictions for the X-ray spectrum of the supermassive black hole Sgr A*. Herein, we present results from updated smooth particle hydrodynamics simulations, building on the architecture of Cuadra et al. and Russell et al., and find that a “cold” (104 K) gas disk forms around Sgr A* with a simulation runtime of 3500 yr. This result is consistent with previous grid-based simulations, demonstrating that a cold disk can form regardless of numerical method. We examine the plasma scenarios arising from an environment with and without this cold disk, by generating synthetic spectra for comparison to the quiescent Fe Kα Sgr A* spectrum from Chandra HETGS, taken through the Chandra X-ray Visionary Program. We find that current and future X-ray missions are unlikely to distinguish between the kinematic signatures in the plasma in these two scenarios. Nonetheless, the stellar wind plasma model presents a good fit to the dispersed Chandra spectra within 1.″5 of Sgr A*. We compare our results to the radiatively inefficient accretion flow (RIAF) model fit to the HETGS spectrum presented in Paper I and find that the Bayesian model evidence does not strongly favor either model. With 9″ angular resolution and high spectral resolution of the X-IFU, NewAthena will offer a clearer differentiation between the RIAF plasma model and hydrodynamic simulations, but only a future X-ray mission with arcsecond resolution will significantly advance our understanding of Sgr A*’s accretion flow in X-rays.
Simulation-based Inference of Radio Millisecond Pulsars in Globular Clusters
Authors: Berteaud Joanna , Eckner Christopher , Calore Francesca , Clavel Maïca , Haggard Daryl
Published: October 2024

Millisecond pulsars (MSPs) are abundant in globular clusters (GCs), which offer favorable environments for their creation. While the advent of recent, powerful facilities led to a rapid increase in MSP discoveries in GCs through pulsation searches, detection biases persist. In this work, we investigate the ability of current and future detections in GCs to constrain the parameters of the MSP population in GCs through a careful study of their luminosity function. Parameters of interest are the number of MSPs hosted by a GC, as well as the mean and the width of their luminosity function, which are typically affected by large uncertainties. While, as we show, likelihood-based studies can lead to ill-behaved posteriors on the size of the MSP population, we introduce a novel, likelihood-free analysis, based on marginal neural ratio estimation, which consistently produces well-behaved posteriors. We focus on the GC Terzan 5 (or Ter 5), which currently counts 48 detected MSPs. We find that 158

−
104

+
294

MSPs should be hosted in this GC, but the uncertainty on this number remains large. We explore the performance of our new method on simulated Terzan 5-like data sets mimicking possible future observational outcomes. We find that significant improvement on the posteriors can be obtained by adding a reliable measurement of the diffuse radio emission of the GC to the analysis or by improving the detection threshold of current radio pulsation surveys by at least a factor of 2.
Multistructured Accretion Flow of Sgr A*. I. Examination of a Radiatively Inefficient Accretion Flow Model
Authors: Balakrishnan Mayura , Corrales Lia , Markoff Sera , Nowak Michael , Haggard Daryl , Wang Q. Daniel , Neilsen Joey , Russell Christopher M. P. , Calderón Diego , Cuadra Jorge , Baganoff Frederick
Published: October 2024

The extreme low-luminosity supermassive black hole Sgr A* provides a unique laboratory in which to test models of radiatively inefficient accretion flows (RIAFs). Previous fits to the quiescent Chandra ACIS-S spectrum found that a RIAF model with an equal inflow–outflow balance works well. In this work, we apply the RIAF model to the Chandra HETG-S spectrum obtained through the Chandra X-ray Visionary Program, which displays features suggestive of temperature and velocity structures within the plasma. A comprehensive forward model analysis accounting for the accretion flow geometry and HETG-S instrumental effects is required for a full interpretation of the quiescent Chandra HETG-S spectrum. We present a RIAF model that takes these effects into account. Our fits to the high-resolution grating spectrum indicate an inflow balanced by an outflow (s ∼ 1) alongside a temperature profile that appears shallower than what would be expected from a gravitational potential following 1/r. The data require that the abundance of iron relative to solar is Z
Fe < 0.32 Z
⊙ (90% credible interval), much lower than the 2 Z
⊙ metallicity measured in nearby late-type giants. While future missions like NewAthena will provide higher spectral resolution, source separation will continue to be a problem. Leveraging Chandra’s unparalleled spatial resolution, which is not expected to be surpassed for decades, remains essential for detailed investigations of the densely populated Galactic center in X-rays.
Reionization Parameter Inference from 3D Minkowski Functionals of the 21 cm Signals
Authors: Diao Kangning , Chen Zhaoting , Chen Xuelei , Mao Yi
Published: October 2024

The Minkowski functionals (MFs), a set of topological summary statistics, have emerged as a powerful tool for extracting non-Gaussian information. We investigate the prospect of constraining the reionization parameters using the MFs of the 21 cm brightness temperature field from the epoch of reionization (EOR). Realistic effects, including thermal noise, synthesized beam, and foreground avoidance, are applied to the mock observations from radio interferometric array experiments such as the Hydrogen Epoch of Reionization Array (HERA) and the Square Kilometre Array (SKA). We demonstrate that the MFs of the 21 cm signal measured with SKA-Low can be used to distinguish different reionization models, whereas the MF measurement with a HERA-like array cannot be made accurately enough. We further forecast the accuracies with which the MF measurements can place constraints on reionization parameters, using the standard Markov Chain Monte Carlo analysis for parameter inference based on forward modeling. We find that for SKA-Low observation, MFs provide unbiased estimations of the reionization parameters with accuracies comparable to the power spectrum (PS) analysis. Furthermore, joint constraints using both MFs and PS can improve the constraint accuracies by up to 30% compared to those with the PS alone. Nevertheless, the constraint accuracies can be degraded if the EOR window is shrunk with strong foreground avoidance. Our analysis demonstrates the promise of MFs as a set of summary statistics that extract complementary information from the 21 cm EOR field to the two-point statistics, which suggests a strong motivation for incorporating the MFs into the data analysis of future 21 cm observations.
Dust-evacuated Zones near Massive Stars: Consequences of Dust Dynamics on Star-forming Regions
Authors: Soliman Nadine H. , Hopkins Philip F. , Grudić Michael Y.
Published: October 2024

Stars form within dense cores composed of both gas and dust within molecular clouds. However, despite the crucial role that dust plays in the star formation process, its dynamics is frequently overlooked, with the common assumption being a constant, spatially uniform dust-to-gas ratio and grain size spectrum. In this study, we introduce a set of radiation-dust-magnetohydrodynamic simulations of star-forming molecular clouds from the STARFORGE project. These simulations expand upon the earlier radiation MHD models, which included cooling, individual star formation, and feedback. Notably, they explicitly address the dynamics of dust grains, considering radiation, drag, and Lorentz forces acting on a diverse size spectrum of live dust grains. We find that once stars exceed a certain mass threshold (∼2 M
⊙), their emitted radiation can evacuate dust grains from their vicinity, giving rise to a dust-suppressed zone of size ∼100 au. This removal of dust, which interacts with gas through cooling, chemistry, drag, and radiative transfer, alters the gas properties in the region. Commencing during the early accretion stages and preceding the main-sequence phase, this process results in a mass-dependent depletion in the accreted dust-to-gas (ADG) mass ratio within both the circumstellar disk and the star. We predict that massive stars (≳10 M
⊙) would exhibit ADG ratios that are approximately 1 order of magnitude lower than that of their parent clouds. Consequently, stars, their disks, and circumstellar environments would display notable deviations in the abundances of elements commonly associated with dust grains, such as carbon and oxygen.
JADES + JEMS: A Detailed Look at the Buildup of Central Stellar Cores and Suppression of Star Formation in Galaxies at Redshifts 3 < z < 4.5
Authors: Ji Zhiyuan , Williams Christina C. , Tacchella Sandro , Suess Katherine A. , Baker William M. , Alberts Stacey , Bunker Andrew J. , Johnson Benjamin D. , Robertson Brant , Sun Fengwu , Eisenstein Daniel J. , Rieke Marcia , Maseda Michael V. , Hainline Kevin , Hausen Ryan , Rieke George , Willmer Christopher N. A. , Egami Eiichi , Shivaei Irene , Carniani Stefano , Charlot Stephane , Chevallard Jacopo , Curtis-Lake Emma , Looser Tobias J. , Maiolino Roberto , Willott Chris , Chen Zuyi , Helton Jakob M. , Lyu Jianwei , Nelson Erica , Bhatawdekar Rachana , Boyett Kristan , Sandles Lester
Published: October 2024

We present a spatially resolved study of stellar populations in six galaxies with stellar masses M
* ∼ 1010
M
☉ at z ∼ 3.7 using 14-filter James Webb Space Telescope (JWST)/NIRCam imaging from the JADES and JEMS surveys. The six galaxies are visually selected to have clumpy substructures with distinct colors over rest frame 3600−4100 Å, including a red, dominant stellar core that is close to their stellar-light centroids. With 23-filter photometry from the Hubble Space Telescope to JWST, we measure the stellar-population properties of individual structural components via spectral energy distribution fitting using Prospector. We find that the central stellar cores are ≳2 times more massive than the Toomre mass, indicating they may not form via single in situ fragmentation. The stellar cores have stellar ages of 0.4−0.7 Gyr that are similar to the timescale of clump inward migration due to dynamical friction, suggesting that they likely instead formed through the coalescence of giant stellar clumps. While they have not yet quenched, the six galaxies are below the star-forming main sequence by 0.2−0.7 dex. Within each galaxy, we find that the specific star formation rate is lower in the central stellar core, and the stellar-mass surface density of the core is already similar to quenched galaxies of the same masses and redshifts. Meanwhile, the stellar ages of the cores are either comparable to or younger than the extended, smooth parts of the galaxies. Our findings are consistent with model predictions of the gas-rich compaction scenario for the buildup of galaxies’ central regions at high redshifts. We are likely witnessing the coeval formation of dense central cores, along with the onset of galaxy-wide quenching at z > 3.
Origin of the Very High Energy Gamma Rays in the Low-luminosity Active Galactic Nucleus NGC 4278
Authors: Lian Ji-Shun , Li Jia-Xuan , Hu Xin-Ke , Gan Ying-Ying , Wu Tan-Zheng , Zhang Hai-Ming , Zhang Jin
Published: October 2024

NGC 4278, a low-luminosity active galactic nucleus, is generally classified as a low-ionization nuclear emission-line region (LINER). Recently, it has been reported to be associated with a very high energy γ-ray source 1LHAASO J1219+2915 in the first Large High Altitude Air Shower Observatory source catalog. However, no associated counterpart has been detected by analyzing the data collected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. By analyzing its X-ray observation data from Swift-XRT, we find that NGC 4278 is in a high-flux state on MJD 59546, with the X-ray flux more than one order of magnitude higher than that observed ∼11.7 yr earlier by Chandra. Interestingly, this Swift-XRT observation was conducted during the active phase of the γ-ray source 1LHAASO J1219+2915. We propose that the detection of very high energy γ-rays from NGC 4278 may be attributed to the presence of an active nucleus in its center. To reproduce the spectral energy distribution (SED) of NGC 4278, we employ a one-zone leptonic model, typically used for fitting broadband SEDs of BL Lacs, and find that a smaller magnetic field strength is required than that of typical TeV BL Lacs. Furthermore, NGC 4278 exhibits significantly lower luminosity in both radio and TeV bands when compared with typical TeV BL Lacs. In the radio luminosity versus Eddington ratio plane, NGC 4278 shows greater similarity to Seyfert galaxies and LINERs than to BL Lacs; however, it still roughly follows the extension toward lower luminosity seen in BL Lacs.
The Progenitor and Central Engine of Short-duration GRB 201006A Associated with a Coherent Radio Flash
Authors: Tian Xiao , Lü HouJun , Yuan Yong , Yang Xing , Yuan HaoYu , Yi ShuangXi , Zhang WenLong , Liang EnWei
Published: October 2024

Recently, the detection of a coherent radio flash associated with short-duration GRB 201006A, occurring 76.6 minutes after the burst, has attracted great attention. However, the physical origin of the coherent radio flash remains under debate. By reanalyzing its data observed by Fermi and Swift, we find that an early radio afterglow as the physical origin of the radio flash can be ruled out, but the coherent radio emission seems to be consistent with the hypothesis of a supramassive magnetar as the central engine collapsing into a black hole. Within this scenario, the derived magnetar surface magnetic field (B

p
) and the initial spin period (P
0) fall into a reasonable range but require a preferably low value of η
R = 10−7 or 10−6. Moreover, the calculated low-ε value and E

γ,iso–E

p
correlation of GRB 201006A also supports the progenitor which is from the merger of compact stars. We also discuss the non-detected kilonova emission associated with GRB 201006A, and then compare with its upper limits of optical observations.
The Photometric Study of EX Dra: A Dwarf Nova Exhibiting a Titled and Precessional Disk
Authors: Liu Wei , Qian Sheng-Bang , Shi Xiang-Dong , Sun Qi-Bin , Fang Xiao-Hui , Wang Qi-Shan
Published: October 2024

We present a photometric study of EX Dra, a dwarf nova that has been extensively observed by the Transiting Exoplanet Survey Satellite. The data reveal the occurrence of 20 complete outbursts, exhibiting several intriguing and rare characteristics. The light curves exhibit a distinct superorbital signal with a period of approximately P
sor ∼ 4.39(7) days, along with a negative superhump showing an approximate period of P
nsh ∼ 4.805(1) hr, indicating that the accretion disk is tilted and undergoing precession with the period of P
sor. In addition, the time-varying nature of P
sor suggests that the precession period is fluctuating.The eclipsing light minima O – C analysis during quiescence shows an oscillation with period of 3.9(5) days, which is a little shorter than the superorbital period. We contend that this is unlikely to be a sudden alteration of the orbital period, but rather, it is influenced by the tilt and precession of the accretion disk. Notably, we found an amplitude shift in the outburst behavior from 3.5 mag with a periodicity of about 26 days to an amplitude of around 2.5 mag with a periodicity of about 12 days, which persisted for 14 yr before reverting. Furthermore, we have extracted quasiperiodic oscillations in the plateau at the noneclipsed phases, characterized by periods ranging between 37 and 40 minutes.
Formation of the Interstellar Sugar Precursor, (Z)-1,2-Ethenediol, through Radical Reactions on Dust Grains
Authors: del Valle Juan Carlos , Redondo Pilar , Kästner Johannes , Molpeceres Germán
Published: October 2024

In recent years, the continued detection of complex organic molecules of prebiotic interest has refueled the interest in a panspermic origin of life. The prebiotic molecule glyceraldehyde is proposed to be formed from (Z)-1,2-ethenediol, a molecule recently detected toward the G+0.693-0.027 molecular cloud at the galactic center. In this work, we computationally simulate the formation of (Z)-1,2-ethenediol from vinyl alcohol on the surface of amorphous solid water in a two-step synthesis involving an OH addition and an H abstraction reaction. In total, we considered all reaction possibilities of the 1,1- and 1,2-OH addition to vinyl alcohol followed by H abstraction or H addition reactions on the resulting radicals. The combination of these reactions is capable of explaining the formation of (Z)-1,2-ethenediol provided a suprathermal diffusion of OH. We also conclude that our proposed formation pathway is not selective and also yields other abstraction and addition products. Key in our findings is the connection between the adsorption modes of the reactants and intermediates and the stereoselectivity of the reactions.
An Estimate of the Impact of Reionization on Supermassive Black Hole Growth
Authors: Upton Sanderbeck Phoebe R. , Johnson Jarrett L. , Marshall Madeline A.
Published: October 2024

The supermassive black holes (SMBHs) that power active galactic nuclei found at z ≥ 6 were formed during the Epoch of Reionization. Because reionization is an inhomogeneous process, the physical properties of SMBH host-galaxy environments will vary spatially during reionization. We construct a semi-analytic model to estimate the impact of reionization on SMBH growth. Using a series of merger trees, reionization models, and black hole (BH) growth models, we find that early reionization can reduce a SMBH’s mass by up to [50, 70, 90]% within dark matter halos of mass [1012, 1011, 1010] M
⊙ by z = 6. Our findings also suggest that the redshift range in which BH growth is impacted by reionization strongly depends on whether the Eddington accretion rate can be exceeded. If so, we find that BH masses are significantly suppressed principally during the early phases of reionization (z ≳ 10), while they are more readily suppressed across the full redshift range if super-Eddington growth is not allowed. We find that the global average impact of reionization may be to reduce the masses of BHs residing in ≲1011
M
⊙ halos by a factor of ≳2. The census of SMBHs being uncovered by the JWST may offer a means to test the basic prediction that more massive BHs reside in cosmological volumes that are reionized at later times.
Percolation Statistics in the MillenniumTNG Simulations
Authors: Regős Enikő , Springel Volker , Bose Sownak , Hadzhiyska Boryana , Hernández-Aguayo César
Published: October 2024

The statistical analysis of cosmic large-scale structure is most often based on simple two-point summary statistics, like the power spectrum or the two-point correlation function of a sample of galaxies or other types of tracers. In contrast, topological measures of clustering are also sensitive to higher-order correlations and thus offer the prospect to access additional information that may harbor important constraining power. We here revisit one such geometric measure of the cosmic web in the form of the so-called percolation analysis, using the recent MillenniumTNG simulation suite of the ΛCDM paradigm. We analyze continuum percolation statistics both for high-resolution dark matter particle distributions and for galaxy mock catalogs from a semianalytic galaxy formation model within a periodic simulation volume of 3000 Mpc on a side. For comparison, we also investigate the percolation statistics of random particle sets and neutrino distributions with two different summed particle masses. We find that the percolation statistics of the dark matter distribution evolves strongly with redshift and thus clustering strength, yielding a progressively lower percolation threshold toward later times. However, there is a sizable residual dependence on numerical resolution, which we interpret as a residual influence of different levels of shot noise. This is corroborated by our analysis of galaxy mock catalogs, whose results depend on sampling density more strongly than on galaxy selection criteria. While this limits the discriminative power of percolation statistics, our results suggest that it still remains useful as a complementary cosmological test when controlled for sampling density.
Lyman Continuum Leakers at z > 3 in the GOODS-S Field: Starburst or Not?
Authors: Zhu 朱 Shuairu 帅儒 , Yuan Fang-Ting , Jiang Chunyan , Zheng Zhen-Ya , Lin Ruqiu
Published: October 2024

We investigate the star-forming properties of 23 Lyman continuum (LyC) leakers at z > 3 in the Great Observatories Origins Deep Survey-South field based on a systematic review of LyC observations from the literature. Using data from the Hubble Space Telescope and the James Webb Space Telescope, we construct the spectral energy distributions for these LyC leakers, covering the spectrum from rest-frame ultraviolet to near-infrared. Through the application of a unified modeling approach, we measure the ultraviolet slope (β), star formation rate, and stellar mass for these LyC leakers in a consistent manner. These high-redshift LyC leakers demonstrate statistically blue UV-continuum slopes (β), which is consistent with their high escape fraction of LyC photons. We find that these high-redshift LyC leakers span a wide range of specific star formation rate (

log
(
sSFR

/yr) from −8.6 to −6.7). Ten of these LyC leakers are located on the star formation main sequence, instead of all being in the starburst mode. The results indicate that intense bursts of star formation are not necessarily required for the leakage of LyC photons for galaxies at z > 3.
Mitigating the Binary Viewing Angle Bias for Standard Sirens
Authors: Salvarese Alberto , Chen Hsin-Yu
Published: October 2024

The inconsistency between experiments in the measurements of the local Universe expansion rate, the Hubble constant, suggests unknown systematics in the existing experiments or new physics. Gravitational-wave standard sirens, a method to independently provide direct measurements of the Hubble constant, have the potential to address this tension. Before that, it is critical to ensure there are no substantial systematics in the standard siren method. A significant systematic has been identified when the viewing angle of the gravitational-wave sources, the compact binary coalescences, was inferred inaccurately from electromagnetic observations of the sources. Such a systematic has led to a more than 10% discrepancy in the standard siren Hubble constant measurements with the observations of binary neutron star merger, GW170817. In this Letter, we develop a new formalism to infer and mitigate this systematic. We demonstrate that the systematic uncertainty of the Hubble constant measurements can be reduced to a level smaller than their statistical uncertainty with 5, 10, and 20 binary neutron star merger observations. We show that our formalism successfully reduces the systematics even if the shape of the biased viewing angle distribution does not follow precisely the model we choose. Our formalism ensures unbiased standard siren Hubble constant measurements when the binary viewing angles are inferred from electromagnetic observations.
Réinventer la ville à l’horizon 2050 avec l’animation vidéo
Authors: Maury Yolande
Published: October 2024

Cet article interroge la mise en relation matérialité(s) et forme lors d’une réinvention de leur ville par des élèves de 6 e . Dans ce cadre (géographie prospective), de courtes animations vidéo sont produites, selon une approche concrète et située : balade urbaine, écriture puis réalisation de « scénar ios d’avenir », dans un jeu de manipulations d’objets, matière à penser la ville. Dans la continuité de Certeau ou Lefebvre, il s’agit d’étudier comment matière, objets et pratiques sociales sont pensés ensemble pour donner forme à des agencements inédits, émergeant de cet « agir collectif », exprimant des imaginaires en actes, et mettant en mouvement quelque chose de nouveau. L’approche est compréhensive, attentive à dégager par quel processus de transformation de la matière les animations opèrent : notamment comment s’effectue la « rencontre » entre matérialité de l’espace produit, matérialité de la ville imaginée, et matérialité du média utilisé, avec ses conventions de manipulation.
Matérialisation d’un dispositif de suppléance communicationnelle
Authors: Marrast Philippe , Bénéjean Marie , Hémont Florian , Patrascu Marcela , Février Antoine , Bazet Isabelle
Published: October 2024

FANS4ALL est un projet de recherche-conception collaboratif, initié par l’Aéroclub des Sourds de France, visant à créer un dispositif de suppléance communicationnelle pour les pilotes sourds dans l’aviation légère de loisir. Actuellement, l’aviation repose sur des échanges vocaux, ce qui exclut en partie les pilotes sourds. Le projet comprend plusieurs phases, de la conception à l’industrialisation. La « matérialité » est essentielle dans ce projet, définie comme la relation entre la matière et les sens des pilotes sourds (vue, audition, toucher). Une méthodologie de recherche multimodale est utilisée, incluant des entretiens, des observations en vol simulé ou réel, et des enregistrements audiovisuels pour comprendre les interactions des pilotes avec leur environnement. L’analyse se focalise sur les interactions entre pilotes, objets techniques et environnement, examinant les formes sociales, organisationnelles et sémiotiques qui résultent d’un processus de conception au long cours. La recherche-conception implique une collaboration avec les acteurs du terrain pour concevoir des dispositifs de suppléance communicationnelle silencieux. L’objectif ultime est de créer des matérialités communicationnelles pour que les pilotes sourds puissent communiquer sans dépendre de la voix, favorisant ainsi leur inclusion et leur sécurité dans l’aviation. Cette inclusion est constitutive de la démarche collaborative que nous menons avec les pilotes sourds.
Informations, communications et matérialités des formes sociales
Authors: Le Moënne Christian
Published: October 2024

L’utilisation constante de la notion d’ « organisation » pour décrire toutes les formes sociales organisées manifeste une certaine faiblesse des conceptualisations, notamment du fait que cette notion est utilisée à la fois pour signifier les processus de structuration organisationnelle et le résultat, temporairement plus ou moins stable, de ces processus. Or, si les différentes formes d’organisations sont des formes sociales plus ou moins « emboitées » entre elles, il est opportun de clarifier cette notion, afin de mieux comprendre comment ces formes sont structurées, comment elles se maintiennent en évoluant constamment. Il s’agira dans un premier temps revenir sur la catégorie de « forme sociale » afin de mettre en évidence que ces entités, qui ne sont pas seulement idéelles, mais articulent pratiquement trois dimensions organisationnelles, objectales et sémiotiques. Il s’agira également essayer de contribuer à faire avancer les recherches sur les processus et pratiques d’information et de communication organisationnelle dans le contexte actuel de la numérisation générale des traces et des formes et le développement d’algorithmes d’apprentissage profond permettant de traiter ces traces et ces formes pour en faire des données susceptibles d’être des informations pour décider et agir.
Engager la responsabilité administrative en cas d'abus sexuels dans l'Église ?
Authors: Fraysse Élise
Published: October 2024

La question de l'engagement de la responsabilité administrative de l'État concernant des abus sexuels commis au sein de l'Église laisse a priori perplexe. Comment l'État, depuis la loi de Séparation de 1905, pourrait-il être tenu pour responsable des actes commis au sein de la sphère religieuse ? Il existe pourtant des cas limites qui permettent de penser – non sans difficulté – cette responsabilité : celui des ministres du culte de l'Alsace-Moselle, laquelle se trouve encore sous régime concordataire, et celui des aumôniers qui officient dans les services publics. Loin d'une conception caricaturale de la séparation des Églises et de l'État, c'est un entremêlement des responsabilités étatique et ecclésiastique qui se dessine.
Réflexion sur le pluralisme en matière de justice à partir des procédures suivies en matière d'abus sexuel dans l'Église
Authors: Jeuland Emmanuel
Published: October 2024

Cette contribution a pour objet d'éclairer la notion de justice plurielle (informelle, transitionnelle, restaurative…) et d'analyser la procédure suivie par la Commission « reconnaissance et réparation » et d'en dénoncer les imperfections. Selon l'auteur, cette instance ne se conforme pas suffisamment aux principes généraux de la procédure.
Réponses judiciaires aux violences conjugales : regards ethnographiques
Authors: Fischer Charlotte
Published: October 2024

Le rapport Pratiques et impacts des réponses judiciaires aux violences conjugales. Regards sur quelques initiatives locales en France est issu d'un appel à projets lancé en 2020 par l'Institut des études et de la recherche sur le droit et la justice. Ce rapport propose un regard ethnographique sur des initiatives et dispositifs judiciaires consacrés aux violences conjugales dans quatre ressorts en France métropolitaine entre 2021 et 2022. Cet article s'attachera à mettre en relation une partie de nos résultats avec la manière dont nous avons travaillé et les spécificités d'une démarche anthropologique et féministe. L'autrice met en lumière les tensions au cœur de la spécialisation de la justice en matière de violences conjugales, en soulignant les défis d'adapter les pratiques pour répondre aux spécificités de ce contentieux, c'est-à-dire des violences masculines faites aux femmes au sein du couple, avec des parcours de victimes variés et des besoins spécifiques propres à chaque cas.
Kafka, un penseur des dérives du pouvoir
Authors: Salas Denis
Published: October 2024

L'œuvre de Kafka (1883-1924) donne à lire des récits où un homme est condamné par un pouvoir absolu et sans recours. Mais cette œuvre relate aussi l'interminable combat qu'il mène contre cette interdiction de vivre qui le frappe. Sans relâche, il tente d'arracher ses droits – ou, du moins, la raison de cette interdiction – aux maîtres anonymes du Tribunal ou du Château. À l'heure du centième anniversaire de sa mort, ce double message n'a rien perdu de sa force. Nous devons plus que jamais combattre les régimes autocratiques en expansion dans notre monde mais aussi lutter contre la tendance des démocraties à banaliser les états d'exception et à réduire les libertés.
La préhistoire au présent
Authors: Balzeau Antoine
Published: October 2024

Mettre des mots sur l’apparence des hommes préhistoriques, voici une promesse qui semble évidente. Mais différents domaines littéraires peuvent avoir des approches très différentes d’un tel objectif. Littérature et science s’imbriquent l’une dans l’autre dès le milieu du xix e siècle, le mystère de la découverte d’Hommes du passé intriguant les auteurs dès cette époque. Mais le lien encore plus fort entre littérature et science est justement que, de tout temps, les scientifiques ont aussi eu recours à leur imagination pour donner une apparence aux hommes préhistoriques. Certaines « images » se sont propagées jusqu’aujourd’hui, d’autres sont combattues par les chercheurs actuels ; pourtant le mélange entre science et imagination reste toujours prégnant.
La préhistoire au présent
Authors: Schwab Catherine
Published: October 2024

Créé en 1862, le Musée Gallo-Romain de Saint-Germain-en-Laye, près de Paris, n’était pas destiné à accueillir des collections issues de l’archéologie préhistorique. Nous verrons donc comment ce jeune domaine scientifique qu’était la préhistoire a été intégré au musée, puis exposé et présenté au public, dans le cadre des premières salles consacrées à ces périodes et des premiers guides les décrivant. Nous verrons également que la préhistoire n’a pas été ainsi nommée à ses débuts et que ce terme n’est apparu que tardivement au Musée des Antiquités nationales.
La préhistoire au présent
Authors: Richard Nathalie
Published: October 2024

À partir des exemples d’Émile Littré, d’Ernest Renan, de Charles Seignobos et de Camille Jullian, cet article met en lumière la manière dont des érudits français se sont emparés des mots « préhistoire » et « préhistorique » pour définir l’histoire, pour penser la frontière entre le connaissable et l’inconnaissable et pour démarquer les enquêtes légitimes des recherches illégitimes. Il évoque des entreprises de construction de limites et d’identités disciplinaires et parle moins des développements de l’archéologie préhistorique que des façons dont un domaine du savoir et ses objets sont instrumentalisés dans des stratégies de positionnement au sein d’un autre champ. Ce faisant, cet article souligne l’importance et l’ambiguïté de l’héritage positiviste vis-à-vis de la préhistoire, ainsi que la polysémie de ce mot au sein des sciences humaines de la seconde moitié du xix e siècle et du début du xx e siècle.
La préhistoire au présent
Authors: Defrance-Jublot Fanny
Published: October 2024

En soustrayant à l’autorité des institutions religieuses les clefs d’un savoir de l’origine qui s’affranchit de la tutelle des textes sacrés, la préhistoire constitue un vecteur parmi d’autres des processus de sécularisation. Le dogme du péché originel, clef de voûte des prescriptions religieuses et des voies d’accès au salut, est notamment fragilisé dans son historicité. Comment les théologiens se sont-ils alors saisis de ce domaine de recherche ?
La préhistoire au présent
Authors: Lenclud Gérard
Published: October 2024

L’entrée de l’homme préhistorique sur la scène académique au xix e siècle contribua à faire en sorte que les Sauvages du Nouveau Monde cessent d’être les contemporains des Civilisés du Vieux Continent, jouant du reste un rôle assez avantageux sur le théâtre où s’affrontent, aux confins du xvii e et du xviii e siècle, les certitudes de l’ordre ancien et les promesses de jours nouveaux, pour devenir les contemporains du mammouth et du rhinocéros laineux. Commués en Primitifs, issus de la nuit des temps, ils prirent d’un coup des milliers d’années.
La préhistoire au présent
Authors: Labrusse Rémi
Published: October 2024

Dès les premiers moments de construction de l’idée de préhistoire humaine, la question de « l’art », au sens occidental et moderne du terme, a joué un rôle central pour lui donner corps et l’environner d’une aura symbolique. Ces moments de fondation, dans la seconde moitié du xix e siècle, ont en effet coïncidé avec ceux où les sociétés occidentales plaçaient au sommet de leurs valeurs ce qu’elles nommaient « art », afin de conjurer des angoisses collectives de perte de sens. Dans ce cadre, l’histoire de l’art a naturellement acquis, dans le domaine préhistorique, une importance extrême, à la croisée de l’analyse technique des témoins matériels et de la spéculation conceptuelle sur leurs significations. Cette esthétisation de la préhistoire est allée de pair avec une volonté d’historicisation, que l’histoire de l’art, comme son nom l’indique, promettait de conforter. Pourtant, c’est le contraire qui s’est produit : concrètement, l’expérience de l’art a intensifié un sentiment de renversement de l’ordre du temps, face aux œuvres dites « préhistoriques ». En tant que disciplines aspirant à un statut scientifique, aussi bien l’histoire de l’art que la préhistoire s’en sont trouvées profondément ébranlées.
La préhistoire au présent
Authors: Vioulac Jean
Published: October 2024

La philosophie apparaît en Grèce ancienne avec le logos : interprétation rationnelle des phénomènes qui rompt avec le monde du mythe pour inaugurer celui de la science. Cette science peut être décrite comme discours rationnel sur les fondements ( archai ), donc comme archéologie. C’est cette archéologie, dans sa pleine authenticité, qu’a entrepris de réinstituer la phénoménologie husserlienne. En poursuivant cette démarche, il s’agit ici de dégager les fondements du moment grec lui-même, en les recherchant dans le processus de néolithisation, ce renversement du rapport de l’homme au monde et à soi dont le parachèvement s’observe à l’époque présente.
La préhistoire au présent
Authors: Schefer Olivier
Published: October 2024

Cet article interroge divers usages de la préhistoire dans la culture populaire des années 1960-1970, en particulier au sein du cinéma de série B et de science-fiction. Véritable point de cristallisation des imaginaires modernes, le temps lointain de la préhistoire sert de prétexte, dans une ère de progrès et de consommation, à la construction de fantasmes et de stéréotypes, il constitue aussi le symptôme d’inquiétudes liées à la menace nucléaire. Un artiste tel que Robert Smithson se saisit par exemple de cette double dimension pour interroger notre « futur préhistorique ».