Pub Date : 2024-09-30DOI: 10.1051/0004-6361/202449704
Giorgos Korkidis, Vasiliki Pavlidou
Context. The average matter density within the turnaround scale, which demarcates where galaxies shift from clustering around a structure to joining the expansion of the Universe, is an important cosmological probe. However, a measurement of the mass enclosed by the turnaround radius is difficult. Analyses of the turnaround scale in simulated galaxy clusters place the turnaround radius at about three times the virial radius in a ΛCDM universe and at a (present-day) density contrast with the background matter density of the Universe of δ ~ 11. Assessing the mass at such extended distances from a cluster’s center is a challenge for current mass measurement techniques. Consequently, there is a need to develop and validate new mass-scaling relations, to connect observable masses at cluster interiors with masses at greater distances.Aims. Our research aims to establish an analytical framework for the most probable mass profile of galaxy clusters, leading to novel mass scaling relations, allowing us to estimate masses at larger scales. We derive such analytical mass profiles and compare them with those from cosmological simulations.Methods. We used excursion set theory, which provides a statistical framework for the density and local environment of dark matter halos, and complement it with the spherical collapse model to follow the non-linear growth of these halos.Results. The profile we developed analytically showed good agreement (better than 30%, and dependent on halo mass) with the mass profiles of simulated galaxy clusters. Mass scaling relations were obtained from the analytical profile with offset better than 15% from the simulated ones. This level of precision highlights the potential of our model for probing structure formation dynamics at the outskirts of galaxy clusters.
{"title":"Mass scaling relations for dark halos from an analytic universal outer density profile","authors":"Giorgos Korkidis, Vasiliki Pavlidou","doi":"10.1051/0004-6361/202449704","DOIUrl":"https://doi.org/10.1051/0004-6361/202449704","url":null,"abstract":"<i>Context.<i/> The average matter density within the turnaround scale, which demarcates where galaxies shift from clustering around a structure to joining the expansion of the Universe, is an important cosmological probe. However, a measurement of the mass enclosed by the turnaround radius is difficult. Analyses of the turnaround scale in simulated galaxy clusters place the turnaround radius at about three times the virial radius in a ΛCDM universe and at a (present-day) density contrast with the background matter density of the Universe of <i>δ<i/> ~ 11. Assessing the mass at such extended distances from a cluster’s center is a challenge for current mass measurement techniques. Consequently, there is a need to develop and validate new mass-scaling relations, to connect observable masses at cluster interiors with masses at greater distances.<i>Aims.<i/> Our research aims to establish an analytical framework for the most probable mass profile of galaxy clusters, leading to novel mass scaling relations, allowing us to estimate masses at larger scales. We derive such analytical mass profiles and compare them with those from cosmological simulations.<i>Methods.<i/> We used excursion set theory, which provides a statistical framework for the density and local environment of dark matter halos, and complement it with the spherical collapse model to follow the non-linear growth of these halos.<i>Results.<i/> The profile we developed analytically showed good agreement (better than 30%, and dependent on halo mass) with the mass profiles of simulated galaxy clusters. Mass scaling relations were obtained from the analytical profile with offset better than 15% from the simulated ones. This level of precision highlights the potential of our model for probing structure formation dynamics at the outskirts of galaxy clusters.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330221","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 : 2024-09-27DOI: 10.1051/0004-6361/202450728
N. Attree, P. Gutiérrez, O. Groussin, J. Bürger, H. U. Keller, T. Kramer, R. Lasagni Manghi, M. Läuter, P. Lemos, J. Markkanen, R. Marschall, C. Schuckart
Aims. We investigate the ability of a simultaneous fitting of comet 67P/Churyumov-Gerasimenko’s non-gravitational forces, torques, and total water-outgassing rate, as observed by Rosetta, to constrain complex thermophysical models of cometary material.Methods. We extend the previous work of fitting geographically defined surface outgassing models to the Rosetta observations by testing the effects of a more detailed geomorphological mapping, the resolution of the shape-model used, self-heating by neighbouring facets on the shape-model, thermal inertia in the outgassing solution, and the variation in the momentum coupling between the gas and the nucleus. We also directly compare the non-gravitational acceleration curves available in the literature.Results. We correct an error in the calculation of pole-orientation in the previous paper. We find that, under the assumptions of the model, non-gravitational forces and torques are driven by water sublimation from the nucleus, thermal inertia and self-heating have only minor effects, spatially uniform activity cannot explain 67P’s non-gravitational dynamics, spatially uniform momentum transfer cannot explain 67P’s non-gravitational dynamics, and different terrain types have different instantaneous responses to insolation.Conclusions. Consolidated terrain facing south on 67P/Churyumov-Gerasimenko has a high outgassing flux, a steep response to insolation, and a large gas momentum transfer coefficient. Instead, that facing north behaves differently, producing little to no water outgassing, and with a lower momentum transfer efficiency. Dusty terrain also has a lower outgassing rate and momentum transfer efficiency, and either depletes its volatile component or is buried in fall-back as the comet approaches the Sun. Momentum transfer appears correlated with insolation, likely due to an increased enhancement in the gas temperature as the dust it flows through is heated.
{"title":"Varying water activity and momentum transfer on comet 67P/Churyumov-Gerasimenko from its non-gravitational forces and torques","authors":"N. Attree, P. Gutiérrez, O. Groussin, J. Bürger, H. U. Keller, T. Kramer, R. Lasagni Manghi, M. Läuter, P. Lemos, J. Markkanen, R. Marschall, C. Schuckart","doi":"10.1051/0004-6361/202450728","DOIUrl":"https://doi.org/10.1051/0004-6361/202450728","url":null,"abstract":"<i>Aims<i/>. We investigate the ability of a simultaneous fitting of comet 67P/Churyumov-Gerasimenko’s non-gravitational forces, torques, and total water-outgassing rate, as observed by Rosetta, to constrain complex thermophysical models of cometary material.<i>Methods<i/>. We extend the previous work of fitting geographically defined surface outgassing models to the Rosetta observations by testing the effects of a more detailed geomorphological mapping, the resolution of the shape-model used, self-heating by neighbouring facets on the shape-model, thermal inertia in the outgassing solution, and the variation in the momentum coupling between the gas and the nucleus. We also directly compare the non-gravitational acceleration curves available in the literature.<i>Results<i/>. We correct an error in the calculation of pole-orientation in the previous paper. We find that, under the assumptions of the model, non-gravitational forces and torques are driven by water sublimation from the nucleus, thermal inertia and self-heating have only minor effects, spatially uniform activity cannot explain 67P’s non-gravitational dynamics, spatially uniform momentum transfer cannot explain 67P’s non-gravitational dynamics, and different terrain types have different instantaneous responses to insolation.<i>Conclusions<i/>. Consolidated terrain facing south on 67P/Churyumov-Gerasimenko has a high outgassing flux, a steep response to insolation, and a large gas momentum transfer coefficient. Instead, that facing north behaves differently, producing little to no water outgassing, and with a lower momentum transfer efficiency. Dusty terrain also has a lower outgassing rate and momentum transfer efficiency, and either depletes its volatile component or is buried in fall-back as the comet approaches the Sun. Momentum transfer appears correlated with insolation, likely due to an increased enhancement in the gas temperature as the dust it flows through is heated.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330225","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 : 2024-09-27DOI: 10.1051/0004-6361/202451901
W. Kollatschny, D. Chelouche
Context. It is generally accepted that all massive galaxies host supermassive black holes (BHs) in their center and that mergers of two galaxies lead to the formation of BH binaries. The most interesting among them comprise the mergers in their final state, that is to say with parsec (3.2 light years) or sub-parsec orbital separations. It is possible to detect these systems with binary self-lensing.Aims. Here we report the potential detection of a central supermassive BH binary in the active galaxy (AGN) NGC 1566 based on a microlensing outburst. The light curve of the outburst – based on observations with the All Sky Automated Survey for SuperNovae – lasted from the beginning of 2017 until the beginning of 2020. The steep symmetric light curve as well as its shape look very different with respect to normal random variations in AGN.Results. However, the observations could be easily reproduced with a best-fit standard microlensing light curve. Based on the light curve, we derived a characteristic timescale of 155 days. During the outburst, the continuum as well as the broad line intensities varied; however, the narrow emission lines did not. This is an indication that the lensing object orbits the AGN nucleus between the broad line region (BLR) and the narrow line region (NLR), that is, at a distance on the order of 250 light days. The light curve can be reproduced by a lens with a BH mass of 5 × 105M⊙. This implies a mass ratio to the central AGN on the order of 1–10.
{"title":"Evidence for gravitational self-lensing of the central supermassive black hole binary in the Seyfert galaxy NGC 1566","authors":"W. Kollatschny, D. Chelouche","doi":"10.1051/0004-6361/202451901","DOIUrl":"https://doi.org/10.1051/0004-6361/202451901","url":null,"abstract":"<i>Context.<i/> It is generally accepted that all massive galaxies host supermassive black holes (BHs) in their center and that mergers of two galaxies lead to the formation of BH binaries. The most interesting among them comprise the mergers in their final state, that is to say with parsec (3.2 light years) or sub-parsec orbital separations. It is possible to detect these systems with binary self-lensing.<i>Aims.<i/> Here we report the potential detection of a central supermassive BH binary in the active galaxy (AGN) NGC 1566 based on a microlensing outburst. The light curve of the outburst – based on observations with the All Sky Automated Survey for SuperNovae – lasted from the beginning of 2017 until the beginning of 2020. The steep symmetric light curve as well as its shape look very different with respect to normal random variations in AGN.<i>Results.<i/> However, the observations could be easily reproduced with a best-fit standard microlensing light curve. Based on the light curve, we derived a characteristic timescale of 155 days. During the outburst, the continuum as well as the broad line intensities varied; however, the narrow emission lines did not. This is an indication that the lensing object orbits the AGN nucleus between the broad line region (BLR) and the narrow line region (NLR), that is, at a distance on the order of 250 light days. The light curve can be reproduced by a lens with a BH mass of 5 × 10<sup>5<sup/> <i>M<i/><sub>⊙<sub/>. This implies a mass ratio to the central AGN on the order of 1–10.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330222","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 : 2024-09-27DOI: 10.1051/0004-6361/202450883
D. Torres-Díaz, R. Basalgète, L. Amiaud, L. Philippe, X. Michaut, J.-H. Fillion, A. Lafosse, M. Bertin
Context. Ammonia is detected both in the gas phase and in the ices of protoplanetary disks. However, its gas phase abundances are still difficult to reproduce via chemical modelling when only the thermal-, UV photon-, and cosmic ray-induced processes are considered. Among other non-thermal mechanisms, X-ray photo-desorption is a relevant pathway to maintaining a budget of molecules in the gas of disks. However, no quantitative data are available to constrain its efficiency in the case of ammonia-containing ices.Aims. We studied the desorption induced by soft X-rays from ammonia ices to determine the photo-desorption yields of neutral molecules that can be applied to the conditions of protoplanetary disks. We also aim to identify the desorption mechanisms at play.Methods. Pure ammonia ices were deposited at 23 or 75 K and irradiated between 395 and 435 eV, with monochromatic synchrotron light. Desorption of neutral molecules and fragments was detected using a quadrupole mass spectrometer, calibrated to obtain des-orption yields. These values were extrapolated and the spectrum of a protoplanetary disk was used to extract average astrophysical desorption yields.Results. Photo-desorption from NH3 ices is dominated by the desorption of neutral NH3 and N2 molecules. The desorption mechanism mostly involves the thermalisation of Auger electrons in the ice, although resonant phenomena also contribute near the N 1s ionisation edge. The NH3 photo-desorption is independent of ice morphology and irradiation temperature. Contrary to NH3 desorption, N2 desorption is sensitive to the photon fluence received by the ice. Average photo-desorption yields derived using the TW Hya X-ray spectrum reveal that the NH3 photo-desorption would be four to six times more efficient than that of H2O. This could be at the origin of unexplained high NH3/H2O abundance ratios predicted in the disk around TW Hya. This result ought to be confirmed by the study of mixed water-ammonia ices.
背景在原行星盘的气相和冰相中都能探测到氨。然而，如果只考虑热、紫外光子和宇宙射线诱导的过程，其气相丰度仍然难以通过化学建模再现。在其他非热机制中，X 射线光解吸是维持星盘气体中分子预算的一个相关途径。然而，对于含氨的冰来说，目前还没有定量数据来确定其效率。我们研究了氨冰在软 X 射线诱导下的解吸，以确定中性分子的光解吸产率，并将其应用到原行星盘的条件中。我们的目的还在于确定起作用的解吸机制。纯氨冰沉积在 23 或 75 K 的温度下，在 395 至 435 eV 之间用单色同步辐射光照射。使用四极质谱仪检测中性分子和碎片的解吸，并进行校准以获得解吸产率。对这些值进行外推，并利用原行星盘的光谱来提取平均天体物理解吸率。NH3 冰的光解吸主要是中性 NH3 和 N2 分子的解吸。解吸机理主要涉及冰中奥杰电子的热化，不过在 N 1s 电离边附近也存在共振现象。NH3 光解吸与冰的形态和辐照温度无关。与 NH3 的解吸相反，N2 的解吸对冰接收到的光子通量很敏感。利用 TW Hya X 射线光谱得出的平均光解吸率显示，NH3 的光解吸效率是 H2O 的四到六倍。这可能是无法解释的 TW Hya 周围圆盘中 NH3/H2O 丰度比过高的原因。这一结果应该通过对水氨混合冰的研究得到证实。
{"title":"X-ray photo-desorption of NH3 and N2 from ammonia ices: Mechanisms and yields in protoplanetary disks","authors":"D. Torres-Díaz, R. Basalgète, L. Amiaud, L. Philippe, X. Michaut, J.-H. Fillion, A. Lafosse, M. Bertin","doi":"10.1051/0004-6361/202450883","DOIUrl":"https://doi.org/10.1051/0004-6361/202450883","url":null,"abstract":"<i>Context<i/>. Ammonia is detected both in the gas phase and in the ices of protoplanetary disks. However, its gas phase abundances are still difficult to reproduce via chemical modelling when only the thermal-, UV photon-, and cosmic ray-induced processes are considered. Among other non-thermal mechanisms, X-ray photo-desorption is a relevant pathway to maintaining a budget of molecules in the gas of disks. However, no quantitative data are available to constrain its efficiency in the case of ammonia-containing ices.<i>Aims<i/>. We studied the desorption induced by soft X-rays from ammonia ices to determine the photo-desorption yields of neutral molecules that can be applied to the conditions of protoplanetary disks. We also aim to identify the desorption mechanisms at play.<i>Methods<i/>. Pure ammonia ices were deposited at 23 or 75 K and irradiated between 395 and 435 eV, with monochromatic synchrotron light. Desorption of neutral molecules and fragments was detected using a quadrupole mass spectrometer, calibrated to obtain des-orption yields. These values were extrapolated and the spectrum of a protoplanetary disk was used to extract average astrophysical desorption yields.<i>Results<i/>. Photo-desorption from NH<sub>3<sub/> ices is dominated by the desorption of neutral NH<sub>3<sub/> and N<sub>2<sub/> molecules. The desorption mechanism mostly involves the thermalisation of Auger electrons in the ice, although resonant phenomena also contribute near the N 1s ionisation edge. The NH<sub>3<sub/> photo-desorption is independent of ice morphology and irradiation temperature. Contrary to NH<sub>3<sub/> desorption, N<sub>2<sub/> desorption is sensitive to the photon fluence received by the ice. Average photo-desorption yields derived using the TW Hya X-ray spectrum reveal that the NH<sub>3<sub/> photo-desorption would be four to six times more efficient than that of H<sub>2<sub/>O. This could be at the origin of unexplained high NH<sub>3<sub/>/H<sub>2<sub/>O abundance ratios predicted in the disk around TW Hya. This result ought to be confirmed by the study of mixed water-ammonia ices.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330226","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 : 2024-09-27DOI: 10.1051/0004-6361/202451829
Valentina Ortúzar-Garzón, Matthias R. Schreiber, Diogo Belloni
Context. Magnetic wind braking drives the spin-down of low-mass stars and the evolution of most interacting binary stars. A magnetic braking prescription that was claimed to reproduce both the period distribution of cataclysmic variables (CVs) and the evolution of the rotation rates of low-mass stars is based on a relation between the angular momentum loss rate and magnetic field complexity.Aims. The magnetic braking model based on field complexity has been claimed to predict a detached phase that could explain the observed period gap in the period distribution of CVs but has never been tested in detailed models of CV evolution. Here we fill this gap.Methods. We incorporated the suggested magnetic braking law in MESA and simulated the evolution of CVs for different initial stellar masses and initial orbital periods.Results. We find that the prescription for magnetic braking based on field complexity fails to reproduce observations of CVs. The predicted secondary star radii are smaller than measured, and an extended detached phase that is required to explain the observed period gap (a dearth of non-magnetic CVs with periods between ∼2 and ∼3 hours) is not predicted.Conclusions. Proposed magnetic braking prescriptions based on a relation between the angular momentum loss rate and field complexity are too weak to reproduce the bloating of donor stars in CVs derived from observations and, in contrast to previous claims, do not provide an explanation for the observed period gap. The suggested steep decrease in the angular momentum loss rate does not lead to detachment. Stronger magnetic braking prescriptions and a discontinuity at the fully convective boundary are needed to explain the evolution of close binary stars that contain compact objects. The tension between braking laws derived from the spin-down of single stars and those required to explain CVs and other close binaries containing compact objects remains.
{"title":"Suggested magnetic braking prescription derived from field complexity fails to reproduce the cataclysmic variable orbital period gap","authors":"Valentina Ortúzar-Garzón, Matthias R. Schreiber, Diogo Belloni","doi":"10.1051/0004-6361/202451829","DOIUrl":"https://doi.org/10.1051/0004-6361/202451829","url":null,"abstract":"<i>Context.<i/> Magnetic wind braking drives the spin-down of low-mass stars and the evolution of most interacting binary stars. A magnetic braking prescription that was claimed to reproduce both the period distribution of cataclysmic variables (CVs) and the evolution of the rotation rates of low-mass stars is based on a relation between the angular momentum loss rate and magnetic field complexity.<i>Aims.<i/> The magnetic braking model based on field complexity has been claimed to predict a detached phase that could explain the observed period gap in the period distribution of CVs but has never been tested in detailed models of CV evolution. Here we fill this gap.<i>Methods.<i/> We incorporated the suggested magnetic braking law in MESA and simulated the evolution of CVs for different initial stellar masses and initial orbital periods.<i>Results.<i/> We find that the prescription for magnetic braking based on field complexity fails to reproduce observations of CVs. The predicted secondary star radii are smaller than measured, and an extended detached phase that is required to explain the observed period gap (a dearth of non-magnetic CVs with periods between ∼2 and ∼3 hours) is not predicted.<i>Conclusions.<i/> Proposed magnetic braking prescriptions based on a relation between the angular momentum loss rate and field complexity are too weak to reproduce the bloating of donor stars in CVs derived from observations and, in contrast to previous claims, do not provide an explanation for the observed period gap. The suggested steep decrease in the angular momentum loss rate does not lead to detachment. Stronger magnetic braking prescriptions and a discontinuity at the fully convective boundary are needed to explain the evolution of close binary stars that contain compact objects. The tension between braking laws derived from the spin-down of single stars and those required to explain CVs and other close binaries containing compact objects remains.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330224","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 : 2024-09-26DOI: 10.1051/0004-6361/202451741
Miguel Pereira-Santaella, Eduardo González-Alfonso, Ismael García-Bernete, Fergus R. Donnan, Miriam G. Santa-Maria, Javier R. Goicoechea, Isabella Lamperti, Michele Perna, Dimitra Rigopoulou
We study the 3.4 − 4.4 μm fundamental rovibrational band of H3+, a key tracer of the ionization of the molecular interstellar medium (ISM), in a sample of 12 local (d < 400 Mpc) (ultra)luminous infrared galaxies ((U)LIRGs) observed with JWST/NIRSpec. The P, Q, and R branches of the band are detected in 13 out of 20 analyzed regions within these (U)LIRGs, which increases the number of extragalactic H3+ detections by a factor of 6. For the first time in the ISM, the H3+ band is observed in emission; we detect this emission in three regions. In the remaining ten regions, the band is seen in absorption. The absorptions are produced toward the 3.4 − 4.4 μm hot dust continuum rather than toward the stellar continuum, indicating that they likely originate in clouds associated with the dust continuum source. The H3+ band is undetected in Seyfert-like (U)LIRGs where the mildly obscured X-ray radiation from the active galactic nuclei might limit the abundance of this molecule. For the detections, the H3+ abundances, N(H3+)/NH = (0.5 − 5.5)×10−7, imply relatively high ionization rates, ζH2, of between 3 × 10−16 and > 4 × 10−15 s−1, which are likely associated with high-energy cosmic rays. In half of the targets, the absorptions are blueshifted by 50–180 km s−1, which is lower than the molecular outflow velocities measured using other tracers such as OH 119 μm or rotational CO lines. This suggests that H3+ traces gas close to the outflow-launching sites before it has been fully accelerated. We used nonlocal thermodynamic equilibrium models to investigate the physical conditions of these clouds. In seven out of ten objects, the H3+ excitation is consistent with inelastic collisions with H2 in warm translucent molecular clouds (Tkin ∼ 250–500 K and n(H2) ∼102 − 3 cm−3). In three objects, dominant infrared pumping excitation is required to explain the absorptions from the (3,0) and (2,1) levels of H3+ detected for the first time in the ISM.
{"title":"H3+ absorption and emission in local (U)LIRGs with JWST/NIRSpec: Evidence for high H2 ionization rates","authors":"Miguel Pereira-Santaella, Eduardo González-Alfonso, Ismael García-Bernete, Fergus R. Donnan, Miriam G. Santa-Maria, Javier R. Goicoechea, Isabella Lamperti, Michele Perna, Dimitra Rigopoulou","doi":"10.1051/0004-6361/202451741","DOIUrl":"https://doi.org/10.1051/0004-6361/202451741","url":null,"abstract":"We study the 3.4 − 4.4 μm fundamental rovibrational band of H<sub>3<sub/><sup>+<sup/>, a key tracer of the ionization of the molecular interstellar medium (ISM), in a sample of 12 local (<i>d<i/> < 400 Mpc) (ultra)luminous infrared galaxies ((U)LIRGs) observed with JWST/NIRSpec. The <i>P<i/>, <i>Q<i/>, and <i>R<i/> branches of the band are detected in 13 out of 20 analyzed regions within these (U)LIRGs, which increases the number of extragalactic H<sub>3<sub/><sup>+<sup/> detections by a factor of 6. For the first time in the ISM, the H<sub>3<sub/><sup>+<sup/> band is observed in emission; we detect this emission in three regions. In the remaining ten regions, the band is seen in absorption. The absorptions are produced toward the 3.4 − 4.4 μm hot dust continuum rather than toward the stellar continuum, indicating that they likely originate in clouds associated with the dust continuum source. The H<sub>3<sub/><sup>+<sup/> band is undetected in Seyfert-like (U)LIRGs where the mildly obscured X-ray radiation from the active galactic nuclei might limit the abundance of this molecule. For the detections, the H<sub>3<sub/><sup>+<sup/> abundances, <i>N<i/>(H<sub>3<sub/><sup>+<sup/>)/<i>N<i/><sub>H<sub/> = (0.5 − 5.5)×10<sup>−7<sup/>, imply relatively high ionization rates, <i>ζ<i/><sub>H<sub>2<sub/><sub/>, of between 3 × 10<sup>−16<sup/> and > 4 × 10<sup>−15<sup/> s<sup>−1<sup/>, which are likely associated with high-energy cosmic rays. In half of the targets, the absorptions are blueshifted by 50–180 km s<sup>−1<sup/>, which is lower than the molecular outflow velocities measured using other tracers such as OH 119 μm or rotational CO lines. This suggests that H<sub>3<sub/><sup>+<sup/> traces gas close to the outflow-launching sites before it has been fully accelerated. We used nonlocal thermodynamic equilibrium models to investigate the physical conditions of these clouds. In seven out of ten objects, the H<sub>3<sub/><sup>+<sup/> excitation is consistent with inelastic collisions with H<sub>2<sub/> in warm translucent molecular clouds (<i>T<i/><sub>kin<sub/> ∼ 250–500 K and <i>n<i/>(H<sub>2<sub/>) ∼10<sup>2 − 3<sup/> cm<sup>−3<sup/>). In three objects, dominant infrared pumping excitation is required to explain the absorptions from the (3,0) and (2,1) levels of H<sub>3<sub/><sup>+<sup/> detected for the first time in the ISM.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325441","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 : 2024-09-25DOI: 10.1051/0004-6361/202450683
M. M. Serim, D. Serim, Ç. K. Dönmez, Y. Tuo, L. Ducci, A. Baykal, A. Santangelo
Aims. We aim to explore the properties of the Be/X-ray binary system MXB 0656–072 from a timing analysis perspective through an investigation of the RXTE/PCA and Fermi/GBM data during its 2007–2008 type I outbursts.Methods. We applied two new techniques, for the first time, along with the conventional Deeter method to produce higher-resolution power density spectra (PDS) of the torque fluctuations. We also investigated the spin frequency evolution of the source by utilising a pulse timing technique.Results. The PDSs show a red noise pattern, with a steepness of Γ ∼ −2 and a saturation timescale of ∼150 d, indicating that MXB 0656–072 is a disc-fed source. With the obtained long term spin frequency evolution, we reveal the torque–luminosity correlation of MXB 0656–072 for the first time. We also demonstrate that the frequency evolution is largely consistent with the Ghosh–Lamb model. In the RXTE/PCA observations, the pulsed emission disappears below ∼5 × 1035 erg s−1, while the profiles remain stable above this value in our analysis time frame. We show that the magnetic field strength deduced from the torque model is compatible with the field strength of the pulsar derived from the cyclotron resonance scattering feature. Utilising the new distance of MXB 0656–072 measured by Gaia, we show that the spectral transition of MXB 0656–072 occurs at a luminosity that matches the expected theoretical transition from the subcritical to supercritical accretion regime.
{"title":"Pulse frequency variations and timing noise of MXB 0656–072 during the 2007–2008 type I outbursts and implications for its magnetic field","authors":"M. M. Serim, D. Serim, Ç. K. Dönmez, Y. Tuo, L. Ducci, A. Baykal, A. Santangelo","doi":"10.1051/0004-6361/202450683","DOIUrl":"https://doi.org/10.1051/0004-6361/202450683","url":null,"abstract":"<i>Aims.<i/> We aim to explore the properties of the Be/X-ray binary system MXB 0656–072 from a timing analysis perspective through an investigation of the RXTE/PCA and <i>Fermi<i/>/GBM data during its 2007–2008 type I outbursts.<i>Methods.<i/> We applied two new techniques, for the first time, along with the conventional Deeter method to produce higher-resolution power density spectra (PDS) of the torque fluctuations. We also investigated the spin frequency evolution of the source by utilising a pulse timing technique.<i>Results.<i/> The PDSs show a red noise pattern, with a steepness of Γ ∼ −2 and a saturation timescale of ∼150 d, indicating that MXB 0656–072 is a disc-fed source. With the obtained long term spin frequency evolution, we reveal the torque–luminosity correlation of MXB 0656–072 for the first time. We also demonstrate that the frequency evolution is largely consistent with the Ghosh–Lamb model. In the RXTE/PCA observations, the pulsed emission disappears below ∼5 × 10<sup>35<sup/> erg s<sup>−1<sup/>, while the profiles remain stable above this value in our analysis time frame. We show that the magnetic field strength deduced from the torque model is compatible with the field strength of the pulsar derived from the cyclotron resonance scattering feature. Utilising the new distance of MXB 0656–072 measured by <i>Gaia<i/>, we show that the spectral transition of MXB 0656–072 occurs at a luminosity that matches the expected theoretical transition from the subcritical to supercritical accretion regime.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325440","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 : 2024-09-23DOI: 10.1051/0004-6361/202451195
A. Tavleev, L. Ducci, V. F. Suleimanov, C. Maitra, K. Werner, A. Santangelo, V. Doroshenko
Context. Classical novae are known to demonstrate a supersoft X-ray source (SSS) state following outbursts. This state is associated with residual thermonuclear burning on the white dwarf (WD) surface. During its all-sky survey (eRASS1), the eROSITA telescope on board the Spectrum-Roentgen-Gamma observatory discovered a bright new SSS, whose position is consistent with the known classical nova AT 2018bej in the Large Magellanic Cloud. There were two eROSITA spectra obtained during the eRASS1 and eRASS2 monitoring epochs and one XMM-Newton grating spectrum close to the eRASS1 epoch.Aims. We aim to describe the eROSITA and follow-up XMM-Newton spectra of AT 2018bej with our local thermodynamic equilibrium (LTE) atmosphere models. We focussed on the evolution of the hot WD properties between the eRASS1 and eRASS2 epochs, especially with respect to the change in carbon abundance.Methods. A grid of LTE model atmosphere spectra was calculated for different values of the effective temperature (from Teff = 525 to 700 kK in steps of 25 kK), surface gravity (six values), and chemical composition, assuming approximately equal hydrogen and helium number fractions, and five different values of carbon and nitrogen abundances.Results. Both eRASS1 and XMM 0.3–0.6 keV spectral analyses yield a temperature of the WD of Teff~ 600 kK and a WD radius of 8000–8700 km. A simultaneous fitting of the eROSITA spectra for two epochs (eRASS1 and eRASS2) with a common WD mass parameter demonstrates a decrease in Teff, accompanied by an increase in the WD radius and a decrease in the carbon abundance. However, these changes are marginal and remain within the errors. The derived WD mass is estimated to be 1.05–1.15 M⊙.Conclusions. We traced a minor evolution of the source on a half-year timescale accompanied by a decrease in the carbon abundance and concluded that LTE model atmospheres can be used to analyse the available X-ray spectra of classical novae during their SSS state.
{"title":"Soft X-ray emission from the classical nova AT 2018bej","authors":"A. Tavleev, L. Ducci, V. F. Suleimanov, C. Maitra, K. Werner, A. Santangelo, V. Doroshenko","doi":"10.1051/0004-6361/202451195","DOIUrl":"https://doi.org/10.1051/0004-6361/202451195","url":null,"abstract":"<i>Context.<i/> Classical novae are known to demonstrate a supersoft X-ray source (SSS) state following outbursts. This state is associated with residual thermonuclear burning on the white dwarf (WD) surface. During its all-sky survey (eRASS1), the eROSITA telescope on board the Spectrum-Roentgen-Gamma observatory discovered a bright new SSS, whose position is consistent with the known classical nova AT 2018bej in the Large Magellanic Cloud. There were two eROSITA spectra obtained during the eRASS1 and eRASS2 monitoring epochs and one <i>XMM-Newton<i/> grating spectrum close to the eRASS1 epoch.<i>Aims.<i/> We aim to describe the eROSITA and follow-up <i>XMM-Newton<i/> spectra of AT 2018bej with our local thermodynamic equilibrium (LTE) atmosphere models. We focussed on the evolution of the hot WD properties between the eRASS1 and eRASS2 epochs, especially with respect to the change in carbon abundance.<i>Methods.<i/> A grid of LTE model atmosphere spectra was calculated for different values of the effective temperature (from <i>T<i/><sub>eff<sub/> = 525 to 700 kK in steps of 25 kK), surface gravity (six values), and chemical composition, assuming approximately equal hydrogen and helium number fractions, and five different values of carbon and nitrogen abundances.<i>Results.<i/> Both eRASS1 and XMM 0.3–0.6 keV spectral analyses yield a temperature of the WD of <i>T<i/><sub>eff<sub/>~ 600 kK and a WD radius of 8000–8700 km. A simultaneous fitting of the eROSITA spectra for two epochs (eRASS1 and eRASS2) with a common WD mass parameter demonstrates a decrease in <i>T<i/><sub>eff<sub/>, accompanied by an increase in the WD radius and a decrease in the carbon abundance. However, these changes are marginal and remain within the errors. The derived WD mass is estimated to be 1.05–1.15 <i>M<i/><sub>⊙<sub/>.<i>Conclusions.<i/> We traced a minor evolution of the source on a half-year timescale accompanied by a decrease in the carbon abundance and concluded that LTE model atmospheres can be used to analyse the available X-ray spectra of classical novae during their SSS state.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142276932","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 : 2024-09-23DOI: 10.1051/0004-6361/202348852
V. Ghirardini, E. Bulbul, E. Artis, N. Clerc, C. Garrel, S. Grandis, M. Kluge, A. Liu, Y. E. Bahar, F. Balzer, I. Chiu, J. Comparat, D. Gruen, F. Kleinebreil, S. Krippendorf, A. Merloni, K. Nandra, N. Okabe, F. Pacaud, P. Predehl, M. E. Ramos-Ceja, T. H. Reiprich, J. S. Sanders, T. Schrabback, R. Seppi, S. Zelmer, X. Zhang, W. Bornemann, H. Brunner, V. Burwitz, D. Coutinho, K. Dennerl, M. Freyberg, S. Friedrich, R. Gaida, A. Gueguen, F. Haberl, W. Kink, G. Lamer, X. Li, T. Liu, C. Maitra, N. Meidinger, S. Mueller, H. Miyatake, S. Miyazaki, J. Robrade, A. Schwope, I. Stewart
The evolution of the cluster mass function traces the growth of linear density perturbations, providing valuable insights into the growth of structures, the nature of dark matter, and the cosmological parameters governing the Universe. The primary science goal of eROSITA, on board the Spectrum Roentgen Gamma (SRG) mission, is to constrain cosmology through the evolution of the cluster mass function. In this paper, we present a set of cosmological constraints obtained from 5259 clusters of galaxies detected over an area of 12791 deg2 in the western Galactic hemisphere of eROSITA’s first All-Sky Survey (eRASS1). The common footprint region (4968 deg2) between the eROSITA Survey and Dark Energy Survey (DES), the Kilo-Degree Survey (KiDS), and the Hyper Supreme Camera (HSC) survey is used for calibration of the scaling between X-ray count rate of the clusters and their total mass through measurements of their weak gravitational lensing signal. The eRASS1 cluster abundances constrain the ΛCDM parameters, namely, the energy density of the total matter to Ωm = 0.29−0.02+0.01 and the normalization of the density fluctuations to σ8 = 0.88 ± 0.02, and their combination yields S8 = σ8(Ωm/0.3)0.5 = 0.86 ± 0.01. These results are consistent and achieve at a similar precision with state-of-the-art cosmic microwave background (CMB) measurements. Furthermore, the eRASS1 cosmological experiment places a most stringent upper limit on the summed masses of left-handed light neutrinos to ∑ mv < 0.43 eV (95% confidence interval) from cluster number counts alone. By combining eRASS1 cluster abundance measurements with CMB- and ground-based neutrino oscillation experiments, we measured the summed neutrino masses to be ∑ mv = 0.09−0.02+0.04 eV or ∑ mv = 0.12−0.02+0.03 eV, assuming a normal or inverted mass hierarchy scenario for neutrino eigenstates. The eRASS1 cluster abundances significantly improve the constraints on the dark energy equation of state parameter to w = −1.12 ± 0.12. When ∑ mv and w are left free, we find consistent results with the concordance ΛCDM cosmology. Our results from the first All-Sky Survey improve the cosmological constraints by over a factor of 5 to 9 over the previous cluster surveys, establishing cluster abundance measurements for precision cosmology and setting the stage for deeper eROSITA All-Sky Surveys, as well as for future cluster abundance experiments.
{"title":"The SRG/eROSITA all-sky survey","authors":"V. Ghirardini, E. Bulbul, E. Artis, N. Clerc, C. Garrel, S. Grandis, M. Kluge, A. Liu, Y. E. Bahar, F. Balzer, I. Chiu, J. Comparat, D. Gruen, F. Kleinebreil, S. Krippendorf, A. Merloni, K. Nandra, N. Okabe, F. Pacaud, P. Predehl, M. E. Ramos-Ceja, T. H. Reiprich, J. S. Sanders, T. Schrabback, R. Seppi, S. Zelmer, X. Zhang, W. Bornemann, H. Brunner, V. Burwitz, D. Coutinho, K. Dennerl, M. Freyberg, S. Friedrich, R. Gaida, A. Gueguen, F. Haberl, W. Kink, G. Lamer, X. Li, T. Liu, C. Maitra, N. Meidinger, S. Mueller, H. Miyatake, S. Miyazaki, J. Robrade, A. Schwope, I. Stewart","doi":"10.1051/0004-6361/202348852","DOIUrl":"https://doi.org/10.1051/0004-6361/202348852","url":null,"abstract":"The evolution of the cluster mass function traces the growth of linear density perturbations, providing valuable insights into the growth of structures, the nature of dark matter, and the cosmological parameters governing the Universe. The primary science goal of eROSITA, on board the Spectrum Roentgen Gamma (SRG) mission, is to constrain cosmology through the evolution of the cluster mass function. In this paper, we present a set of cosmological constraints obtained from 5259 clusters of galaxies detected over an area of 12791 deg<sup>2<sup/> in the western Galactic hemisphere of eROSITA’s first All-Sky Survey (eRASS1). The common footprint region (4968 deg<sup>2<sup/>) between the eROSITA Survey and Dark Energy Survey (DES), the Kilo-Degree Survey (KiDS), and the Hyper Supreme Camera (HSC) survey is used for calibration of the scaling between X-ray count rate of the clusters and their total mass through measurements of their weak gravitational lensing signal. The eRASS1 cluster abundances constrain the ΛCDM parameters, namely, the energy density of the total matter to Ω<sub>m<sub/> = 0.29<sub>−0.02<sub/><sup>+0.01<sup/> and the normalization of the density fluctuations to <i>σ<i/><sub>8<sub/> = 0.88 ± 0.02, and their combination yields <i>S<i/><sub>8<sub/> = <i>σ<i/><sub>8<sub/>(Ω<sub>m<sub/>/0.3)<sup>0.5<sup/> = 0.86 ± 0.01. These results are consistent and achieve at a similar precision with state-of-the-art cosmic microwave background (CMB) measurements. Furthermore, the eRASS1 cosmological experiment places a most stringent upper limit on the summed masses of left-handed light neutrinos to ∑ <i>m<sub>v<sub/> <<i/> 0.43 eV (95% confidence interval) from cluster number counts alone. By combining eRASS1 cluster abundance measurements with CMB- and ground-based neutrino oscillation experiments, we measured the summed neutrino masses to be ∑ <i>m<sub>v<sub/><i/> = 0.09<sub>−0.02<sub/><sup>+0.04<sup/> eV or ∑ <i>m<sub>v<sub/><i/> = 0.12<sub>−0.02<sub/><sup>+0.03<sup/> eV, assuming a normal or inverted mass hierarchy scenario for neutrino eigenstates. The eRASS1 cluster abundances significantly improve the constraints on the dark energy equation of state parameter to <i>w<i/> = −1.12 ± 0.12. When ∑ <i>m<sub>v<sub/><i/> and <i>w<i/> are left free, we find consistent results with the concordance ΛCDM cosmology. Our results from the first All-Sky Survey improve the cosmological constraints by over a factor of 5 to 9 over the previous cluster surveys, establishing cluster abundance measurements for precision cosmology and setting the stage for deeper eROSITA All-Sky Surveys, as well as for future cluster abundance experiments.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142276849","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 : 2024-09-23DOI: 10.1051/0004-6361/202450091
Meenu Upadhyay, Markus Meuwly
Context. The dynamics of molecule formation, relaxation, diffusion, and desorption on amorphous solid water (ASW) is studied in a quantitative fashion.Aims. The formation probability, stabilization, energy relaxation, and diffusion dynamics of CO2 and NO2 on cold ASW following atom+diatom recombination reactions are characterized quantitatively.Methods. Accurate machine-learned energy functions combined with fluctuating charge models were used to investigate the diffusion, interactions, and recombination dynamics of atomic oxygen with CO and NO on ASW. Energy relaxation to the ASW and into water internal degrees of freedom were determined from the analysis of the vibrational density of states. The surface diffusion and desorption energetics were investigated with extended and nonequilibrium MD simulations.Results. The reaction probability is determined quantitatively and it is demonstrated that surface diffusion of the reactants on the nanosecond time scale leads to recombination for initial separations of up to 20 Å. After recombination, both CO2 and NO2 stabilize by energy transfer to water internal and surface phonon modes on the picosecond timescale. The average diffusion barriers and desorption energies agree with those reported from experiments, which validates the energy functions. After recombination, the triatomic products diffuse easily, which contrasts with the equilibrium situation, in which both CO2 and NO2 are stationary on the multinanosecond timescale.
背景。定量研究分子在无定形固体水（ASW）上的形成、弛豫、扩散和解吸动力学。定量表征原子+二原子重组反应后 CO2 和 NO2 在冷 ASW 上的形成概率、稳定性、能量弛豫和扩散动力学。采用精确的机器学习能量函数结合波动电荷模型，研究原子氧与 CO 和 NO 在 ASW 上的扩散、相互作用和重组动力学。通过分析振动状态密度，确定了向 ASW 和水内部自由度的能量弛豫。通过扩展和非平衡 MD 模拟研究了表面扩散和解吸的能量学。定量确定了反应概率，并证明了反应物在纳秒时间尺度上的表面扩散会导致初始分离度高达 20 Å 的重组。平均扩散障碍和解吸能与实验报告的结果一致，从而验证了能量函数。重组后，三原子产物很容易扩散，这与二氧化碳和二氧化氮在多纳秒时间尺度上都处于静止状态的平衡状态形成了鲜明对比。
{"title":"CO2 and NO2 formation on amorphous solid water","authors":"Meenu Upadhyay, Markus Meuwly","doi":"10.1051/0004-6361/202450091","DOIUrl":"https://doi.org/10.1051/0004-6361/202450091","url":null,"abstract":"<i>Context.<i/> The dynamics of molecule formation, relaxation, diffusion, and desorption on amorphous solid water (ASW) is studied in a quantitative fashion.<i>Aims.<i/> The formation probability, stabilization, energy relaxation, and diffusion dynamics of CO<sub>2<sub/> and NO<sub>2<sub/> on cold ASW following atom+diatom recombination reactions are characterized quantitatively.<i>Methods.<i/> Accurate machine-learned energy functions combined with fluctuating charge models were used to investigate the diffusion, interactions, and recombination dynamics of atomic oxygen with CO and NO on ASW. Energy relaxation to the ASW and into water internal degrees of freedom were determined from the analysis of the vibrational density of states. The surface diffusion and desorption energetics were investigated with extended and nonequilibrium MD simulations.<i>Results.<i/> The reaction probability is determined quantitatively and it is demonstrated that surface diffusion of the reactants on the nanosecond time scale leads to recombination for initial separations of up to 20 Å. After recombination, both CO<sub>2<sub/> and NO<sub>2<sub/> stabilize by energy transfer to water internal and surface phonon modes on the picosecond timescale. The average diffusion barriers and desorption energies agree with those reported from experiments, which validates the energy functions. After recombination, the triatomic products diffuse easily, which contrasts with the equilibrium situation, in which both CO<sub>2<sub/> and NO<sub>2<sub/> are stationary on the multinanosecond timescale.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142276893","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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