Pub Date : 2025-02-19DOI: 10.1051/0004-6361/202451556
Riccardo J. Truant, David Izquierdo-Villalba, Alberto Sesana, Golam Mohiuddin Shaifullah, Matteo Bonetti
Pulsar timing array (PTA) collaborations have reported evidence of a nano-hertz (nano-Hz) stochastic gravitational wave background (sGWB) that is compatible with an adiabatically inspiraling population of massive black hole binaries (MBHBs). Despite the large uncertainties, the relatively flat spectral slope of the recovered signal suggests a possible prominent role of MBHB dynamical coupling with the environment and/or the presence of an eccentric MBHB population. This work is aimed at studying the capabilities of future PTA experiments to detect single MBHBs under the realistic assumption that the sGWB is originated from an eccentric binary population coupled with its environment. To this end, we generalised the standard signal-to-noise ratio (S/N) and Fisher information matrix calculations used in PTA for circular MBHBs to the case of eccentric systems. We considered an ideal 10-year MeerKAT and 30-year SKA PTAs and applied our method across a wide number of simulated eccentric MBHB populations. We find that the number of resolvable MBHBs for the SKA (MeerKAT) PTA is ∼30 (4) at S/N > 5 (> 3), featuring an increasing trend for larger eccentricity values of the MBHB population. This is the result of eccentric MBHBs at ≲10−9 Hz emitting part of their power at high harmonics, thus reaching the PTA sensitivity band. Our results also indicate that resolved MBHBs do not follow the eccentricity distribution of the underlying MBHB population; instead, low eccentricity values appear to be preferred (< 0.6). Finally, the recovery of binary intrinsic properties and sky localisation do not depend on the system eccentricity, while orbital parameters such as the eccentricity and initial orbital phase show clear trends. Despite their simplified nature, our results demonstrate that SKA will enable the detection of tens of MBHBs, ushering the community into the era of precision gravitational wave astronomy at nano-Hz frequencies.
{"title":"Resolving the nano-hertz gravitational wave sky: The detectability of eccentric binaries with PTA experiments","authors":"Riccardo J. Truant, David Izquierdo-Villalba, Alberto Sesana, Golam Mohiuddin Shaifullah, Matteo Bonetti","doi":"10.1051/0004-6361/202451556","DOIUrl":"https://doi.org/10.1051/0004-6361/202451556","url":null,"abstract":"Pulsar timing array (PTA) collaborations have reported evidence of a nano-hertz (nano-Hz) stochastic gravitational wave background (sGWB) that is compatible with an adiabatically inspiraling population of massive black hole binaries (MBHBs). Despite the large uncertainties, the relatively flat spectral slope of the recovered signal suggests a possible prominent role of MBHB dynamical coupling with the environment and/or the presence of an eccentric MBHB population. This work is aimed at studying the capabilities of future PTA experiments to detect single MBHBs under the realistic assumption that the sGWB is originated from an eccentric binary population coupled with its environment. To this end, we generalised the standard signal-to-noise ratio (S/N) and Fisher information matrix calculations used in PTA for circular MBHBs to the case of eccentric systems. We considered an ideal 10-year MeerKAT and 30-year SKA PTAs and applied our method across a wide number of simulated eccentric MBHB populations. We find that the number of resolvable MBHBs for the SKA (MeerKAT) PTA is ∼30 (4) at S/N > 5 (> 3), featuring an increasing trend for larger eccentricity values of the MBHB population. This is the result of eccentric MBHBs at ≲10<sup>−9<sup/> Hz emitting part of their power at high harmonics, thus reaching the PTA sensitivity band. Our results also indicate that resolved MBHBs do not follow the eccentricity distribution of the underlying MBHB population; instead, low eccentricity values appear to be preferred (< 0.6). Finally, the recovery of binary intrinsic properties and sky localisation do not depend on the system eccentricity, while orbital parameters such as the eccentricity and initial orbital phase show clear trends. Despite their simplified nature, our results demonstrate that SKA will enable the detection of tens of MBHBs, ushering the community into the era of precision gravitational wave astronomy at nano-Hz frequencies.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"62 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143452002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-19DOI: 10.1051/0004-6361/202452517
Marcelo Tala Pinto, Andrés Jordán, Lorena Acuña, Matías Jones, Rafael Brahm, Yared Reinarz, Jan Eberhardt, Néstor Espinoza, Thomas Henning, Melissa Hobson, Felipe Rojas, Martin Schlecker, Trifon Trifonov, Gaspar Bakos, Gavin Boyle, Zoltan Csubry, Joel Hartmann, Benjamin Knepper, Laura Kreidberg, Vincent Suc, Johanna Teske, Robert Paul Butler, Jeffrey Crane, Steve Schectman, Ian Thompson, Dave Osip, George Ricker, Karen A. Collins, Cristilyn N. Watkins, Allyson Bieryla, Chris Stockdale, Gavin Wang, Roberto Zambelli, Sara Seager, Joshua Winn, Mark E. Rose, Malena Rice, Zahra Essack
We report the discovery and characterization of three new transiting giant planets orbiting TOI-6628, TOI-3837, and TOI-5027 and one new warm sub-Saturn orbiting TOI-2328, whose transits events were detected in the light curves of the Transiting Exoplanet Survey Satellite (TESS) space mission. By combining TESS light curves with ground-based photometric and spectroscopic followup observations, we confirm the planetary nature of the observed transits and radial velocity variations. TOI-6628 b has a mass of 0.74±0.06 MJ and a radius of 0.98−0.05+0.06RJ and orbits a metal-rich star with a period of 18.18424 ± 0.00001 days and an eccentricity of 0.670−0.016+0.015, making it one of the most eccentric orbits of all known warm giants. TOI-3837 b has a mass of 0.59±0.05 MJ and a radius of 0.97−0.06+0.05RJ and orbits its host star every 11.88865 ± 0.00003 days, with a moderate eccentricity of 0.221−0.046+0.042. With a mass of 2.02±0.13 MJ and a radius of 0.96−0.06+0.05RJ, TOI-5027 b orbits its host star in an eccentric orbit with e = 0.385−0.026+0.025 every 10.24368±0.00001 days. TOI-2328 b is a Saturn-like planet with a mass of 0.16±0.02 MJ and a radius of 0.89−0.05+0.04RJ; it orbits its host star in a nearly circular orbit with e = 0.057−0.029+0.046 at a period of 17.10197±0.00001 days. All four planets have orbital periods above ten days, and our planet’s interior structure models are consistent with a rocky-icy core with an H/He envelope, providing evidence supporting the core-accretion model of planet formation for this kind of planet.
{"title":"Three warm Jupiters orbiting TOI-6628, TOI-3837, and TOI-5027 and one sub-Saturn orbiting TOI-2328★","authors":"Marcelo Tala Pinto, Andrés Jordán, Lorena Acuña, Matías Jones, Rafael Brahm, Yared Reinarz, Jan Eberhardt, Néstor Espinoza, Thomas Henning, Melissa Hobson, Felipe Rojas, Martin Schlecker, Trifon Trifonov, Gaspar Bakos, Gavin Boyle, Zoltan Csubry, Joel Hartmann, Benjamin Knepper, Laura Kreidberg, Vincent Suc, Johanna Teske, Robert Paul Butler, Jeffrey Crane, Steve Schectman, Ian Thompson, Dave Osip, George Ricker, Karen A. Collins, Cristilyn N. Watkins, Allyson Bieryla, Chris Stockdale, Gavin Wang, Roberto Zambelli, Sara Seager, Joshua Winn, Mark E. Rose, Malena Rice, Zahra Essack","doi":"10.1051/0004-6361/202452517","DOIUrl":"https://doi.org/10.1051/0004-6361/202452517","url":null,"abstract":"We report the discovery and characterization of three new transiting giant planets orbiting TOI-6628, TOI-3837, and TOI-5027 and one new warm sub-Saturn orbiting TOI-2328, whose transits events were detected in the light curves of the Transiting Exoplanet Survey Satellite (TESS) space mission. By combining TESS light curves with ground-based photometric and spectroscopic followup observations, we confirm the planetary nature of the observed transits and radial velocity variations. TOI-6628 <i>b<i/> has a mass of 0.74±0.06 <i>M<i/><sub>J<sub/> and a radius of 0.98<sub>−0.05<sub/><sup>+0.06<sup/> <i>R<sub>J<sub/><i/> and orbits a metal-rich star with a period of 18.18424 ± 0.00001 days and an eccentricity of 0.670<sub>−0.016<sub/><sup>+0.015<sup/>, making it one of the most eccentric orbits of all known warm giants. TOI-3837 <i>b<i/> has a mass of 0.59±0.05 <i>M<i/><sub>J<sub/> and a radius of 0.97<sub>−0.06<sub/><sup>+0.05<sup/> <i>R<sub>J<sub/><i/> and orbits its host star every 11.88865 ± 0.00003 days, with a moderate eccentricity of 0.221<sub>−0.046<sub/><sup>+0.042<sup/>. With a mass of 2.02±0.13 <i>M<i/><sub>J<sub/> and a radius of 0.96<sub>−0.06<sub/><sup>+0.05<sup/> <i>R<sub>J<sub/><i/>, TOI-5027 <i>b<i/> orbits its host star in an eccentric orbit with <i>e<i/> = 0.385<sub>−0.026<sub/><sup>+0.025<sup/> every 10.24368±0.00001 days. TOI-2328 <i>b<i/> is a Saturn-like planet with a mass of 0.16±0.02 <i>M<i/><sub>J<sub/> and a radius of 0.89<sub>−0.05<sub/><sup>+0.04<sup/> <i>R<sub>J<sub/><i/>; it orbits its host star in a nearly circular orbit with <i>e<i/> = 0.057<sub>−0.029<sub/><sup>+0.046<sup/> at a period of 17.10197±0.00001 days. All four planets have orbital periods above ten days, and our planet’s interior structure models are consistent with a rocky-icy core with an H/He envelope, providing evidence supporting the core-accretion model of planet formation for this kind of planet.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"1 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143452048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-19DOI: 10.1051/0004-6361/202452405
B. Prinoth, J. V. Seidel, H. J. Hoeijmakers, B. M. Morris, M. Baratella, N. W. Borsato, Y. C. Damasceno, V. Parmentier, D. Kitzmann, E. Sedaghati, L. Pino, F. Borsa, R. Allart, N. Santos, M. Steiner, A. Suárez Mascareño, H. Tabernero, M. R. Zapatero Osorio
Transit spectroscopy usually relies on the integration of one or several transits to achieve the signal-to-noise ratio (S/N) necessary to resolve spectral features. Consequently, high-S/N observations of exoplanet atmospheres, where we can forgo integration, are essential for disentangling the complex chemistry and dynamics beyond global trends. In this study, we combined two partial 4-UT transits of the ultrahot Jupiter WASP-121 b, observed with the ESPRESSO at the European Southern Observatory’s Very Large Telescope in order to revisit its titanium chemistry. Through cross-correlation analysis, we achieved detections of H I, Li I, Na I, K I, Mg I, Ca I, Ti I, V I, Cr I, Mn I, Fe I, Fe II, Co I, Ni I, Ba II, Sr I, and Sr II. Additionally, narrow-band spectroscopy allowed us to resolve strong single lines, resulting in significant detections of Hα, Hβ, Hγ, Li I, Na I, K I, Mg I, Ca II, Sr I, Sr II, and Mn I. Our most notable finding is the high-significance detection of Ti I (∼5σ per spectrum, and ∼19σ stacked in the planetary rest frame). Comparison with atmospheric models reveals that Ti I is indeed depleted compared to V I. We also resolve the planetary velocity traces of both Ti I and V I, with Ti I exhibiting a significant blueshift toward the end of the transit. This suggests that Ti I primarily originates from low-latitude regions within the super-rotating jet observed in WASP-121 b. Our observations suggest limited mixing between the equatorial jet and the mid-latitudes, in contrast with model predictions from General Circulation Models. We also report the non-detection of TiO, which we attribute to inaccuracies in the line list that could hinder its detection, even if present. Thus, the final determination of the presence of TiO must await space-based observations. We conclude that the 4-UT mode of ESPRESSO is an excellent testbed for achieving high S/N on relatively faint targets, paving the way for future observations with the Extremely Large Telescope.
{"title":"Titanium chemistry of WASP-121 b with ESPRESSO in 4-UT mode","authors":"B. Prinoth, J. V. Seidel, H. J. Hoeijmakers, B. M. Morris, M. Baratella, N. W. Borsato, Y. C. Damasceno, V. Parmentier, D. Kitzmann, E. Sedaghati, L. Pino, F. Borsa, R. Allart, N. Santos, M. Steiner, A. Suárez Mascareño, H. Tabernero, M. R. Zapatero Osorio","doi":"10.1051/0004-6361/202452405","DOIUrl":"https://doi.org/10.1051/0004-6361/202452405","url":null,"abstract":"Transit spectroscopy usually relies on the integration of one or several transits to achieve the signal-to-noise ratio (S/N) necessary to resolve spectral features. Consequently, high-S/N observations of exoplanet atmospheres, where we can forgo integration, are essential for disentangling the complex chemistry and dynamics beyond global trends. In this study, we combined two partial 4-UT transits of the ultrahot Jupiter WASP-121 b, observed with the ESPRESSO at the European Southern Observatory’s Very Large Telescope in order to revisit its titanium chemistry. Through cross-correlation analysis, we achieved detections of H I, Li I, Na I, K I, Mg I, Ca I, Ti I, V I, Cr I, Mn I, Fe I, Fe II, Co I, Ni I, Ba II, Sr I, and Sr II. Additionally, narrow-band spectroscopy allowed us to resolve strong single lines, resulting in significant detections of H<i>α<i/>, H<i>β<i/>, H<i>γ<i/>, Li I, Na I, K I, Mg I, Ca II, Sr I, Sr II, and Mn I. Our most notable finding is the high-significance detection of Ti I (∼5<i>σ<i/> per spectrum, and ∼19<i>σ<i/> stacked in the planetary rest frame). Comparison with atmospheric models reveals that Ti I is indeed depleted compared to V I. We also resolve the planetary velocity traces of both Ti I and V I, with Ti I exhibiting a significant blueshift toward the end of the transit. This suggests that Ti I primarily originates from low-latitude regions within the super-rotating jet observed in WASP-121 b. Our observations suggest limited mixing between the equatorial jet and the mid-latitudes, in contrast with model predictions from General Circulation Models. We also report the non-detection of TiO, which we attribute to inaccuracies in the line list that could hinder its detection, even if present. Thus, the final determination of the presence of TiO must await space-based observations. We conclude that the 4-UT mode of ESPRESSO is an excellent testbed for achieving high S/N on relatively faint targets, paving the way for future observations with the Extremely Large Telescope.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"14 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143451663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-19DOI: 10.1051/0004-6361/202452808
Ziang Yan, Angus H. Wright, Nora Elisa Chisari, Christos Georgiou, Shahab Joudaki, Arthur Loureiro, Robert Reischke, Marika Asgari, Maciej Bilicki, Andrej Dvornik, Catherine Heymans, Hendrik Hildebrandt, Priyanka Jalan, Benjamin Joachimi, Giorgio Francesco Lesci, Shun-Sheng Li, Laila Linke, Constance Mahony, Lauro Moscardini, Nicola R. Napolitano, Benjamin Stölzner, Maximilian Von Wietersheim-Kramsta, Mijin Yoon
Photometric galaxy surveys, despite their limited resolution along the line of sight, encode rich information about the large-scale structure (LSS) of the Universe thanks to the high number density and extensive depth of the data. However, the complicated selection effects in wide and deep surveys can potentially cause significant bias in the angular two-point correlation function (2PCF) measured from those surveys. In this paper, we measure the 2PCF from the newly published KiDS-Legacy sample. Given an r-band 5σ magnitude limit of 24.8 and survey footprint of 1347 deg2, it achieves an excellent combination of sky coverage and depth for such a measurement. We find that complex selection effects, primarily induced by varying seeing, introduce over-estimation of the 2PCF by approximately an order of magnitude. To correct for such effects, we apply a machine learning-based method to recover an organised random (OR) that presents the same selection pattern as the galaxy sample. The basic idea is to find the selection-induced clustering of galaxies using a combination of self-organising maps (SOMs) and hierarchical clustering (HC). This unsupervised machine learning method is able to recover complicated selection effects without specifying their functional forms. We validate this SOM+HC method on mock deep galaxy samples with realistic systematics and selections derived from the KiDS-Legacy catalogue. Using mock data, we demonstrate that the OR delivers unbiased 2PCF cosmological parameter constraints, removing the 27σ offset in the galaxy bias parameter that is recovered when adopting uniform randoms. Blinded measurements on the real KiDS-Legacy data show that the corrected 2PCF is robust to the SOM+HC configuration near the optimal set-up suggested by the mock tests.
{"title":"KiDS-Legacy: Angular galaxy clustering from deep surveys with complex selection effects","authors":"Ziang Yan, Angus H. Wright, Nora Elisa Chisari, Christos Georgiou, Shahab Joudaki, Arthur Loureiro, Robert Reischke, Marika Asgari, Maciej Bilicki, Andrej Dvornik, Catherine Heymans, Hendrik Hildebrandt, Priyanka Jalan, Benjamin Joachimi, Giorgio Francesco Lesci, Shun-Sheng Li, Laila Linke, Constance Mahony, Lauro Moscardini, Nicola R. Napolitano, Benjamin Stölzner, Maximilian Von Wietersheim-Kramsta, Mijin Yoon","doi":"10.1051/0004-6361/202452808","DOIUrl":"https://doi.org/10.1051/0004-6361/202452808","url":null,"abstract":"Photometric galaxy surveys, despite their limited resolution along the line of sight, encode rich information about the large-scale structure (LSS) of the Universe thanks to the high number density and extensive depth of the data. However, the complicated selection effects in wide and deep surveys can potentially cause significant bias in the angular two-point correlation function (2PCF) measured from those surveys. In this paper, we measure the 2PCF from the newly published KiDS-Legacy sample. Given an <i>r<i/>-band 5<i>σ<i/> magnitude limit of 24.8 and survey footprint of 1347 deg<sup>2<sup/>, it achieves an excellent combination of sky coverage and depth for such a measurement. We find that complex selection effects, primarily induced by varying seeing, introduce over-estimation of the 2PCF by approximately an order of magnitude. To correct for such effects, we apply a machine learning-based method to recover an organised random (OR) that presents the same selection pattern as the galaxy sample. The basic idea is to find the selection-induced clustering of galaxies using a combination of self-organising maps (SOMs) and hierarchical clustering (HC). This unsupervised machine learning method is able to recover complicated selection effects without specifying their functional forms. We validate this SOM+HC method on mock deep galaxy samples with realistic systematics and selections derived from the KiDS-Legacy catalogue. Using mock data, we demonstrate that the OR delivers unbiased 2PCF cosmological parameter constraints, removing the 27<i>σ<i/> offset in the galaxy bias parameter that is recovered when adopting uniform randoms. Blinded measurements on the real KiDS-Legacy data show that the corrected 2PCF is robust to the SOM+HC configuration near the optimal set-up suggested by the mock tests.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"50 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143452112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-19DOI: 10.1051/0004-6361/202452460
Anne Hutter, Elie R. Cueto, Pratika Dayal, Stefan Gottlöber, Maxime Trebitsch, Gustavo Yepes
Context. The James Webb Space Telescope (JWST) has uncovered an abundance of z > 10 galaxies bright in the ultraviolet (UV), whose presence poses a challenge to traditional theoretical models at high redshifts. Various new models have recently emerged to address this discrepancy by refining their description of star formation.Aims. Here, we investigate whether modifications to the stellar initial mass function (IMF) alone can reproduce the z > 10 UV luminosity functions (UV LFs) when the star formation rate is used as a proxy for the fraction of massive stars.Methods. We incorporated an evolving IMF into the ASTRAEUS galaxy evolution and reionisation simulation framework, which becomes increasingly top-heavy as the gas density in a galaxy rises above a given threshold. Our implementation accounts for the IMF’s effects on supernova (SN) feedback and metal enrichment, as well as UV and ionising emissivities.Results. For this evolving IMF model, we find that (i) the maximum UV luminosity enhancement is twice as large in massive galaxies (ΔMUV ≃ 2.6) than those where star formation is strongly limited by SN feedback (ΔMUV ≃ 1.3); (ii) it successfully reproduces the observed UV LFs at z = 5 − 15; (iii) galaxies with top-heavy IMFs exhibit the highest star formation rates, driven by their location in local density peaks, which facilitates higher gas accretion rates; (iv) the 1σ variances in the UV luminosity are only slightly higher compared to when assuming a Salpeter IMF, but the 2σ variances are significantly increased by a factor of 1.4 − 2 boosting the abundance of UV-bright galaxies at z > 10; and (v) reionisation begins earlier with more extended large ionised regions and fewer smaller ones during its initial stages, although these differences diminish at lower redshifts, leading to a similar end of reionisation at z ≃ 5.6.
背景。詹姆斯-韦伯太空望远镜（JWST）发现了大量紫外线（UV）明亮的z > 10星系，它们的存在对高红移下的传统理论模型提出了挑战。最近出现了各种新的模型，通过改进对恒星形成的描述来解决这一差异。 在这里，我们研究了当恒星形成率被用来替代大质量恒星的比例时，仅对恒星初始质量函数（IMF）的修改是否能够重现z > 10紫外发光函数（UV LFs）。我们在ASTRAEUS星系演化和再电离模拟框架中加入了一个不断演化的IMF，当星系中的气体密度超过给定阈值时，IMF就会变得越来越头重脚轻。我们的实施考虑了IMF对超新星（SN）反馈和金属富集以及紫外线和电离辐射的影响。对于这个不断演化的 IMF 模型，我们发现：(i) 在大质量星系（ΔMUV ≃2.6）中，紫外线光度的最大增强是那些恒星形成受到 SN 反馈强烈限制的星系（ΔMUV ≃ 1.3）；(ii) 它成功地再现了 z = 5 - 15 时观测到的紫外低频；(iii) 具有顶重型 IMF 的星系表现出最高的恒星形成率，这是由于它们位于局部密度峰值，这有利于提高气体吸积率；(iv) 与假定 Salpeter IMF 时相比，紫外光度的 1σ 方差仅略微增大，但 2σ 方差却显著增大了 1 倍。4 - 2，从而提高了 z > 10 时紫外亮星系的丰度；以及（v）再电离开始得更早，在其初始阶段，大电离区扩展得更多，而小电离区则更少，尽管这些差异在较低红移时会减小，导致再电离在 z ≃ 5.6 时结束得相似。
{"title":"ASTRAEUS","authors":"Anne Hutter, Elie R. Cueto, Pratika Dayal, Stefan Gottlöber, Maxime Trebitsch, Gustavo Yepes","doi":"10.1051/0004-6361/202452460","DOIUrl":"https://doi.org/10.1051/0004-6361/202452460","url":null,"abstract":"<i>Context.<i/> The James Webb Space Telescope (JWST) has uncovered an abundance of <i>z<i/> > 10 galaxies bright in the ultraviolet (UV), whose presence poses a challenge to traditional theoretical models at high redshifts. Various new models have recently emerged to address this discrepancy by refining their description of star formation.<i>Aims.<i/> Here, we investigate whether modifications to the stellar initial mass function (IMF) alone can reproduce the <i>z<i/> > 10 UV luminosity functions (UV LFs) when the star formation rate is used as a proxy for the fraction of massive stars.<i>Methods.<i/> We incorporated an evolving IMF into the ASTRAEUS galaxy evolution and reionisation simulation framework, which becomes increasingly top-heavy as the gas density in a galaxy rises above a given threshold. Our implementation accounts for the IMF’s effects on supernova (SN) feedback and metal enrichment, as well as UV and ionising emissivities.<i>Results.<i/> For this evolving IMF model, we find that (i) the maximum UV luminosity enhancement is twice as large in massive galaxies (Δ<i>M<i/><sub>UV<sub/> ≃ 2.6) than those where star formation is strongly limited by SN feedback (Δ<i>M<i/><sub>UV<sub/> ≃ 1.3); (ii) it successfully reproduces the observed UV LFs at <i>z<i/> = 5 − 15; (iii) galaxies with top-heavy IMFs exhibit the highest star formation rates, driven by their location in local density peaks, which facilitates higher gas accretion rates; (iv) the 1<i>σ<i/> variances in the UV luminosity are only slightly higher compared to when assuming a Salpeter IMF, but the 2<i>σ<i/> variances are significantly increased by a factor of 1.4 − 2 boosting the abundance of UV-bright galaxies at <i>z<i/> > 10; and (v) reionisation begins earlier with more extended large ionised regions and fewer smaller ones during its initial stages, although these differences diminish at lower redshifts, leading to a similar end of reionisation at <i>z<i/> ≃ 5.6.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"11 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143452047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-19DOI: 10.1051/0004-6361/202452364
Jorge Sánchez Almeida, Ignacio Trujillo, Mireia Montes, Angel R. Plastino
We present a new technique to constrain the gravitational potential of a galaxy from the observed stellar mass surface density alone under a number of assumptions. It uses the classical Eddington inversion method to compute the phase-space distribution function (DF) needed for stars to reside in a given gravitational potential. In essence, each potential defines a set of density profiles, and it is the expansion of the observed profile in this database that provides the DF. If the required DF becomes negative, then the potential is inconsistent with the observed stars and can be discarded. It is particularly well suited for analyzing low-mass low surface brightness galaxies, where photometric but not spectroscopic data can be obtained. The recently discovered low surface brightness galaxy Nube was used to showcase its application. For Nube’s observed stellar core to be reproduced with a non-negative DF, cuspy NFW (Navarro, Frenk, and White) potentials are highly disfavored compared with potentials that have cores (Schuster-Plummer or ρ230). The method assumes the stellar system to have spherical symmetry and isotropic velocity distribution; however, we discuss simple extensions that relax the need for isotropy and may help to drop the spherical symmetry assumption.
{"title":"Constraining the shape of dark matter haloes using only starlight","authors":"Jorge Sánchez Almeida, Ignacio Trujillo, Mireia Montes, Angel R. Plastino","doi":"10.1051/0004-6361/202452364","DOIUrl":"https://doi.org/10.1051/0004-6361/202452364","url":null,"abstract":"We present a new technique to constrain the gravitational potential of a galaxy from the observed stellar mass surface density alone under a number of assumptions. It uses the classical Eddington inversion method to compute the phase-space distribution function (DF) needed for stars to reside in a given gravitational potential. In essence, each potential defines a set of density profiles, and it is the expansion of the observed profile in this database that provides the DF. If the required DF becomes negative, then the potential is inconsistent with the observed stars and can be discarded. It is particularly well suited for analyzing low-mass low surface brightness galaxies, where photometric but not spectroscopic data can be obtained. The recently discovered low surface brightness galaxy Nube was used to showcase its application. For Nube’s observed stellar core to be reproduced with a non-negative DF, cuspy NFW (Navarro, Frenk, and White) potentials are highly disfavored compared with potentials that have cores (Schuster-Plummer or <i>ρ<i/><sub>230<sub/>). The method assumes the stellar system to have spherical symmetry and isotropic velocity distribution; however, we discuss simple extensions that relax the need for isotropy and may help to drop the spherical symmetry assumption.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"15 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143452109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-18DOI: 10.1051/0004-6361/202453509
Cs. Kiss, N. Takács, Cs. E. Kalup, R. Szakáts, L. Molnár, E. Plachy, K. Sárneczky, R. Szabó, Gy. M. Szabó, A. Bódi, A. Pál
We report on the identification of the three fastest rotating Jovian trojans with reliable population assignments known to date, discovered using light curve data from the Transiting Exoplanet Satellite Survey mission and confirmed by Zwicky Transient Facility data. For two of our targets the rotation periods are moderately below the previously accepted ∼5 h Jovian trojan breakup limit (4.26 and 4.75 h); however, the rotation period of (13383) was found to be P = 2.926 h, leading to a density estimate of ρ ≈1.6 g cm−3, higher than the generally accepted ≲1 g cm−3 density limit of Jovian trojans. If associated with lower densities, this rotation rate requires considerable cohesion, of the order of a few kilopascals. The relatively high albedo (pV ≈ 0.11) and fast rotation suggest that (13383) may have undergone an energetic collision that spun up the body and exposed bright material to the surface.
{"title":"Three fast-rotating Jovian trojans identified by TESS set new population density limits","authors":"Cs. Kiss, N. Takács, Cs. E. Kalup, R. Szakáts, L. Molnár, E. Plachy, K. Sárneczky, R. Szabó, Gy. M. Szabó, A. Bódi, A. Pál","doi":"10.1051/0004-6361/202453509","DOIUrl":"https://doi.org/10.1051/0004-6361/202453509","url":null,"abstract":"We report on the identification of the three fastest rotating Jovian trojans with reliable population assignments known to date, discovered using light curve data from the Transiting Exoplanet Satellite Survey mission and confirmed by <i>Zwicky<i/> Transient Facility data. For two of our targets the rotation periods are moderately below the previously accepted ∼5 h Jovian trojan breakup limit (4.26 and 4.75 h); however, the rotation period of (13383) was found to be P = 2.926 h, leading to a density estimate of <i>ρ<i/> ≈1.6 g cm<sup>−3<sup/>, higher than the generally accepted ≲1 g cm<sup>−3<sup/> density limit of Jovian trojans. If associated with lower densities, this rotation rate requires considerable cohesion, of the order of a few kilopascals. The relatively high albedo (p<sub><i>V<i/><sub/> ≈ 0.11) and fast rotation suggest that (13383) may have undergone an energetic collision that spun up the body and exposed bright material to the surface.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"64 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-18DOI: 10.1051/0004-6361/202452900
A. Taillard, R. Martín-Doménech, H. Carrascosa, J. A. Noble, G. M. Muñoz Caro, E. Dartois, D. Navarro-Almaida, B. Escribano, Á. Sánchez-Monge, A. Fuente
To date, gas phase observations of sulphur in dense interstellar environments have only constrained the molecular carriers of ~1% of its predicted cosmic abundance. An additional ~5% is known to be locked up in molecular solids in dense clouds, leaving the main reservoir of depleted sulphur in the solid phase yet to be identified. Overall, OCS is the only S-bearing molecule unambiguously detected in interstellar ices thus far with infrared telescopes, although an absorption feature of SO<sub>2<sub/> has been plausibly identified at 7.5 µm. The spectral resolution and sensitivity of the <i>James Webb<i/> Space Telescope (JWST) could make a substantial difference in detecting part of this missing sulphur. The wavelength coverage of the JWST includes vibrational absorption features of the S-carriers H<sub>2<sub/>S, OCS, SO<sub>2<sub/>, CS<sub>2<sub/>, SO, CS, and S<sub>8<sub/> are found. The aim of this study is to determine whether these molecules may be viable candidates for detection. We carried out new laboratory measurements of the IR absorption spectra of CS<sub>2<sub/> and S<sub>8<sub/> to update the IR band strength of the most intense CS<sub>2<sub/> absorption feature at 6.8 µm, as well as to determine that of S<sub>8<sub/> at 20.3 µm for the first time. These data, along with values previously reported in the literature for H<sub>2<sub/>S, OCS, and SO<sub>2<sub/>, allow us to evaluate which S-bearing species could be potentially detected with JWST in interstellar ices. Taking the literature abundances of the major ice species determined by previous IR observations towards starless cores, low-mass young stellar objects (LYSOs) and massive young stellar objects (MYSOs), we generated simulated IR spectra using the characteristics of the instruments on the JWST. Thus, we have been able to establish a case study for three stages of the star formation process. These spectra were simulated using a tool that produces synthetic ice spectra, with the aim of studying the feasibility of detecting S-bearing species with the JWST by artificially adding S-bearing molecules to the simulated spectra. We conclude that the detection of S-bearing molecules remains challenging due to a variety of parameters; principally, the overlap of absorption features with those of other species and the mixing of molecular species in the ice impacting the profile and central position of the targeted bands. Despite these obstacles, the detection of H<sub>2<sub/>S in dense clouds – and potentially SO<sub>2<sub/> in LYSOs and MYSOs – should be possible in regions with favourable physical and chemical conditions, but not necessarily in the same region. In contrast, the large allotrope S<sub>8<sub/> would remain undetected even in the unrealistic case that all the available sulphur atoms were involved in its formation. Although the sensitivity of JWST is insufficient to determine the sulphur budget in the solid state, the detection of (or setting of significant upper limits on
{"title":"Predicting the detectability of sulphur-bearing molecules in the solid phase with simulated spectra of JWST instruments","authors":"A. Taillard, R. Martín-Doménech, H. Carrascosa, J. A. Noble, G. M. Muñoz Caro, E. Dartois, D. Navarro-Almaida, B. Escribano, Á. Sánchez-Monge, A. Fuente","doi":"10.1051/0004-6361/202452900","DOIUrl":"https://doi.org/10.1051/0004-6361/202452900","url":null,"abstract":"To date, gas phase observations of sulphur in dense interstellar environments have only constrained the molecular carriers of ~1% of its predicted cosmic abundance. An additional ~5% is known to be locked up in molecular solids in dense clouds, leaving the main reservoir of depleted sulphur in the solid phase yet to be identified. Overall, OCS is the only S-bearing molecule unambiguously detected in interstellar ices thus far with infrared telescopes, although an absorption feature of SO<sub>2<sub/> has been plausibly identified at 7.5 µm. The spectral resolution and sensitivity of the <i>James Webb<i/> Space Telescope (JWST) could make a substantial difference in detecting part of this missing sulphur. The wavelength coverage of the JWST includes vibrational absorption features of the S-carriers H<sub>2<sub/>S, OCS, SO<sub>2<sub/>, CS<sub>2<sub/>, SO, CS, and S<sub>8<sub/> are found. The aim of this study is to determine whether these molecules may be viable candidates for detection. We carried out new laboratory measurements of the IR absorption spectra of CS<sub>2<sub/> and S<sub>8<sub/> to update the IR band strength of the most intense CS<sub>2<sub/> absorption feature at 6.8 µm, as well as to determine that of S<sub>8<sub/> at 20.3 µm for the first time. These data, along with values previously reported in the literature for H<sub>2<sub/>S, OCS, and SO<sub>2<sub/>, allow us to evaluate which S-bearing species could be potentially detected with JWST in interstellar ices. Taking the literature abundances of the major ice species determined by previous IR observations towards starless cores, low-mass young stellar objects (LYSOs) and massive young stellar objects (MYSOs), we generated simulated IR spectra using the characteristics of the instruments on the JWST. Thus, we have been able to establish a case study for three stages of the star formation process. These spectra were simulated using a tool that produces synthetic ice spectra, with the aim of studying the feasibility of detecting S-bearing species with the JWST by artificially adding S-bearing molecules to the simulated spectra. We conclude that the detection of S-bearing molecules remains challenging due to a variety of parameters; principally, the overlap of absorption features with those of other species and the mixing of molecular species in the ice impacting the profile and central position of the targeted bands. Despite these obstacles, the detection of H<sub>2<sub/>S in dense clouds – and potentially SO<sub>2<sub/> in LYSOs and MYSOs – should be possible in regions with favourable physical and chemical conditions, but not necessarily in the same region. In contrast, the large allotrope S<sub>8<sub/> would remain undetected even in the unrealistic case that all the available sulphur atoms were involved in its formation. Although the sensitivity of JWST is insufficient to determine the sulphur budget in the solid state, the detection of (or setting of significant upper limits on ","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"34 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-18DOI: 10.1051/0004-6361/202452420
M. Latour, S. Kamann, S. Martocchia, T.-O. Husser, S. Saracino, S. Dreizler
Context. Multiple populations are ubiquitous in the old massive globular clusters (GCs) of the Milky Way. It is still unclear how they arose during the formation of a GC. The topic of iron and metallicity variations has recently attracted attention with the measurement of iron variations among the primordial population (P1) stars of Galactic GCs.Aims. We explore the relationship between the metallicity of the P1 stars on the red-giant branch (RGB) of Galactic GCs and their ∆F275W,F814W pseudo-color. We also measure the metallicity dispersion of P1 and P2 stars.Methods. We used the spectra of more than 8000 RGB stars in 21 Galactic GCs observed with the integral-field spectrograph MUSE to derive individual stellar metallicities, [M/H]. For each cluster, we used Hubble Space Telescope photometric catalogs to separate the stars into two main populations (P1 and P2). We measured the metallicity spread within the primordial population of each cluster by combining our metallicity measurements with the stars’ ∆F275W,F814W pseudo-color. We also derived metallicity dispersions (σ[M/H]) for the P1 and P2 stars of each GC.Results. In all but three GCs we find a significant correlation between the metallicity and the ∆F275W,F814W pseudo-color of the P1 stars: stars with larger ∆F275W,F814W have higher metallicities. We measure metallicity spreads that range from 0.03 to 0.24 dex and correlate with the GC masses. As for the intrinsic metallicity dispersions, when combining the P1 and P2 stars, we measure values ranging from 0.02 dex to 0.08 dex, which correlate very well with the GC masses. The two clusters that show the largest σ[M/H] are NGC 6388 and NGC 6441. The P2 stars have metallicity dispersions that are smaller than or equal to those of the P1 stars.Conclusions. We present a homogeneous spectroscopic characterization of the metallicities of the P1 and P2 stars in a set of 21 Galactic GCs. We find that both the metallicity spreads of the P1 stars (from the ∆F275W,F814W spread on the chromosome maps) and the metallicity dispersions (σ[M/H]) correlate with the GC masses, as predicted by some theoretical self-enrichment models presented in the literature.
{"title":"A stellar census in globular clusters with MUSE","authors":"M. Latour, S. Kamann, S. Martocchia, T.-O. Husser, S. Saracino, S. Dreizler","doi":"10.1051/0004-6361/202452420","DOIUrl":"https://doi.org/10.1051/0004-6361/202452420","url":null,"abstract":"<i>Context<i/>. Multiple populations are ubiquitous in the old massive globular clusters (GCs) of the Milky Way. It is still unclear how they arose during the formation of a GC. The topic of iron and metallicity variations has recently attracted attention with the measurement of iron variations among the primordial population (P1) stars of Galactic GCs.<i>Aims<i/>. We explore the relationship between the metallicity of the P1 stars on the red-giant branch (RGB) of Galactic GCs and their ∆<sub>F275W,F814W<sub/> pseudo-color. We also measure the metallicity dispersion of P1 and P2 stars.<i>Methods<i/>. We used the spectra of more than 8000 RGB stars in 21 Galactic GCs observed with the integral-field spectrograph MUSE to derive individual stellar metallicities, [M/H]. For each cluster, we used <i>Hubble<i/> Space Telescope photometric catalogs to separate the stars into two main populations (P1 and P2). We measured the metallicity spread within the primordial population of each cluster by combining our metallicity measurements with the stars’ ∆<sub>F275W,F814W<sub/> pseudo-color. We also derived metallicity dispersions (<i>σ<i/><sub>[M/H]<sub/>) for the P1 and P2 stars of each GC.<i>Results<i/>. In all but three GCs we find a significant correlation between the metallicity and the ∆<sub>F275W,F814W<sub/> pseudo-color of the P1 stars: stars with larger ∆<sub>F275W,F814W<sub/> have higher metallicities. We measure metallicity spreads that range from 0.03 to 0.24 dex and correlate with the GC masses. As for the intrinsic metallicity dispersions, when combining the P1 and P2 stars, we measure values ranging from 0.02 dex to 0.08 dex, which correlate very well with the GC masses. The two clusters that show the largest <i>σ<i/><sub>[M/H]<sub/> are NGC 6388 and NGC 6441. The P2 stars have metallicity dispersions that are smaller than or equal to those of the P1 stars.<i>Conclusions<i/>. We present a homogeneous spectroscopic characterization of the metallicities of the P1 and P2 stars in a set of 21 Galactic GCs. We find that both the metallicity spreads of the P1 stars (from the ∆<sub>F275W,F814W<sub/> spread on the chromosome maps) and the metallicity dispersions (<i>σ<i/><sub>[M/H]<sub/>) correlate with the GC masses, as predicted by some theoretical self-enrichment models presented in the literature.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"13 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-18DOI: 10.1051/0004-6361/202452928
G. Castelló, M. Luna, J. Terradas
Context. Solar filament oscillations have been observed for many years, but recent advances in telescope capabilities now enable a daily monitoring of these periodic motions. This offers valuable insights into the structure of filaments. A systematic study of filament oscillations over the solar cycle can shed light on the evolution of the prominences. Only manual techniques were used so far to analyze these oscillations.Aims. This work serves as a proof of concept and demonstrates the effectiveness of convolutional neural networks (CNNs). These networks automatically detect filament oscillations by applying a power-spectrum analysis to Hα data from the GONG telescope network.Methods. The proposed technique studies periodic fluctuations in every pixel of the Hα data cubes. Using the Lomb-Scargle periodogram, we computed the power spectral density (PSD) of the dataset. The background noise fits a combination of red and white noise well. Using Bayesian statistics and Markov chain Monte Carlo (MCMC) algorithms, we fit the spectra and determined the confidence threshold of a given percentage to search for real oscillations. We built two CNN models to obtain the same results as with the MCMC approach.Results. We applied the CNN models to some observations reported in the literature to prove its reliability in detecting the same events as the classical methods. A day with events that were not previously reported was studied to determine the model capabilities beyond a controlled dataset that we can check with previous reports.Conclusions. CNNs prove to be a useful tool for studying solar filament oscillations using spectral techniques. The computing times are significantly reduced for results that are similar enough to the classical methods. This is a relevant step toward the automatic detection of filament oscillations.
{"title":"Fast Bayesian spectral analysis using convolutional neural networks: Applications to GONG Hα solar data","authors":"G. Castelló, M. Luna, J. Terradas","doi":"10.1051/0004-6361/202452928","DOIUrl":"https://doi.org/10.1051/0004-6361/202452928","url":null,"abstract":"<i>Context<i/>. Solar filament oscillations have been observed for many years, but recent advances in telescope capabilities now enable a daily monitoring of these periodic motions. This offers valuable insights into the structure of filaments. A systematic study of filament oscillations over the solar cycle can shed light on the evolution of the prominences. Only manual techniques were used so far to analyze these oscillations.<i>Aims<i/>. This work serves as a proof of concept and demonstrates the effectiveness of convolutional neural networks (CNNs). These networks automatically detect filament oscillations by applying a power-spectrum analysis to Hα data from the GONG telescope network.<i>Methods<i/>. The proposed technique studies periodic fluctuations in every pixel of the Hα data cubes. Using the Lomb-Scargle periodogram, we computed the power spectral density (PSD) of the dataset. The background noise fits a combination of red and white noise well. Using Bayesian statistics and Markov chain Monte Carlo (MCMC) algorithms, we fit the spectra and determined the confidence threshold of a given percentage to search for real oscillations. We built two CNN models to obtain the same results as with the MCMC approach.<i>Results<i/>. We applied the CNN models to some observations reported in the literature to prove its reliability in detecting the same events as the classical methods. A day with events that were not previously reported was studied to determine the model capabilities beyond a controlled dataset that we can check with previous reports.<i>Conclusions<i/>. CNNs prove to be a useful tool for studying solar filament oscillations using spectral techniques. The computing times are significantly reduced for results that are similar enough to the classical methods. This is a relevant step toward the automatic detection of filament oscillations.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"2 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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