Pub Date : 2025-03-19DOI: 10.1051/0004-6361/202450326
Jesper Nielsen, Anders Johansen, Komal Bali, Caroline Dorn
The radius distribution of close-in planets has been observed to have a bimodal distribution, with a dearth of planets around ~1.5–2.0 R⊕ commonly referred to as the ‘radius valley’. The origin of the valley is normally attributed to mass-loss processes such as photoevaporation or core-powered mass loss. Recent work, however, has suggested that the radius valley may instead arise as a consequence of gas accretion by low-mass planets. Therefore in this work, we aim to investigate the formation of a primordial radius valley from the formation of planet cores through pebble accretion up until the dissipation of the protoplanetary disc and subsequent contraction of accreted atmospheres. The goal of this work is to explore the conditions for forming a primordial radius valley from the first principles of planet formation theory, rather than attempting to explain the detailed structure of the observed valley. We used an analytical model with minimal assumptions to estimate the contraction rate of atmospheres and find the formation of a primordial radius valley. The planets smaller than the valley did not reach the pebble isolation mass, which is required for the planets to cool down sufficiently to be able to accrete a significant amount of gas. We also estimated the slopes of the radius gap as a function of orbital period for the intrinsic population as well as for planets with orbital periods of less than 100 days. For the intrinsic population, the radius gap follows the pebble isolation mass and increases with increasing orbital period, but for close-in planets, the direction of the slope reverses and decreases with increasing orbital period. We find that planets smaller than the radius valley are predominantly rocky, while the population of planets larger than the valley comprises a mixture of rocky and water-rich planets.
{"title":"A primordial radius valley as a consequence of planet formation","authors":"Jesper Nielsen, Anders Johansen, Komal Bali, Caroline Dorn","doi":"10.1051/0004-6361/202450326","DOIUrl":"https://doi.org/10.1051/0004-6361/202450326","url":null,"abstract":"The radius distribution of close-in planets has been observed to have a bimodal distribution, with a dearth of planets around ~1.5–2.0 <i>R<i/><sub>⊕<sub/> commonly referred to as the ‘radius valley’. The origin of the valley is normally attributed to mass-loss processes such as photoevaporation or core-powered mass loss. Recent work, however, has suggested that the radius valley may instead arise as a consequence of gas accretion by low-mass planets. Therefore in this work, we aim to investigate the formation of a primordial radius valley from the formation of planet cores through pebble accretion up until the dissipation of the protoplanetary disc and subsequent contraction of accreted atmospheres. The goal of this work is to explore the conditions for forming a primordial radius valley from the first principles of planet formation theory, rather than attempting to explain the detailed structure of the observed valley. We used an analytical model with minimal assumptions to estimate the contraction rate of atmospheres and find the formation of a primordial radius valley. The planets smaller than the valley did not reach the pebble isolation mass, which is required for the planets to cool down sufficiently to be able to accrete a significant amount of gas. We also estimated the slopes of the radius gap as a function of orbital period for the intrinsic population as well as for planets with orbital periods of less than 100 days. For the intrinsic population, the radius gap follows the pebble isolation mass and increases with increasing orbital period, but for close-in planets, the direction of the slope reverses and decreases with increasing orbital period. We find that planets smaller than the radius valley are predominantly rocky, while the population of planets larger than the valley comprises a mixture of rocky and water-rich planets.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"92 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143661341","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 : 2025-03-18DOI: 10.1051/0004-6361/202451337
P. Barrère, J. Guilet, R. Raynaud, A. Reboul-Salze
The formation of highly magnetized young neutron stars, called magnetars, is still a strongly debated topic. One promising scenario invokes the amplification of the magnetic field by the Tayler-Spruit dynamo in a proto-neutron star (PNS) that is spun up by fall-back. Our previous numerical study supports this scenario by demonstrating that this dynamo can generate magnetar-like magnetic fields in stably stratified Boussinesq models of a PNS interior. To further investigate the Tayler-Spruit dynamo, we performed 3D magnetohydrodynamic (MHD) numerical simulations with the MagIC code, varying the ratio between the Brunt-Väisälä frequency and the rotation rate. We first demonstrated that a self-sustained dynamo process can be maintained for a Brunt-Väisälä frequency about four times higher than the angular rotation frequency. The generated magnetic fields and angular momentum transport follow the scaling laws derived in prior analytical investigations, confirming our earlier results. We also report, for the first time, the existence of an intermittent Tayler-Spruit dynamo. For a typical PNS Brunt-Väisälä frequency of 1 kHz, the axisymmetric toroidal and dipolar magnetic fields range between 1.2 × 1015–2 × 1016 G and 1.4 × 1013–3 × 1015 G, for rotation periods of 1 − 10 ms. Moreover, the total magnetic field remains ≳1014 G for periods of ≲60 ms. Thus, our results suggest that our scenario is promising to form classical fast-rotating magnetars and magnetars with weaker magnetic dipoles for slower rotations. We offer a calibration of the analytical scaling laws based on our simulations, with a dimensionless normalisation factor of the order of 10−2. As the Tayler-Spruit dynamo is often invoked for the angular momentum transport in stellar radiative zones, our results are of particular significance to asteroseismology as well.
{"title":"Tayler-Spruit dynamo in stably stratified rotating fluids: Application to proto-magnetars","authors":"P. Barrère, J. Guilet, R. Raynaud, A. Reboul-Salze","doi":"10.1051/0004-6361/202451337","DOIUrl":"https://doi.org/10.1051/0004-6361/202451337","url":null,"abstract":"The formation of highly magnetized young neutron stars, called magnetars, is still a strongly debated topic. One promising scenario invokes the amplification of the magnetic field by the Tayler-Spruit dynamo in a proto-neutron star (PNS) that is spun up by fall-back. Our previous numerical study supports this scenario by demonstrating that this dynamo can generate magnetar-like magnetic fields in stably stratified Boussinesq models of a PNS interior. To further investigate the Tayler-Spruit dynamo, we performed 3D magnetohydrodynamic (MHD) numerical simulations with the MagIC code, varying the ratio between the Brunt-Väisälä frequency and the rotation rate. We first demonstrated that a self-sustained dynamo process can be maintained for a Brunt-Väisälä frequency about four times higher than the angular rotation frequency. The generated magnetic fields and angular momentum transport follow the scaling laws derived in prior analytical investigations, confirming our earlier results. We also report, for the first time, the existence of an intermittent Tayler-Spruit dynamo. For a typical PNS Brunt-Väisälä frequency of 1 kHz, the axisymmetric toroidal and dipolar magnetic fields range between 1.2 × 10<sup>15<sup/>–2 × 10<sup>16<sup/> G and 1.4 × 10<sup>13<sup/>–3 × 10<sup>15<sup/> G, for rotation periods of 1 − 10 ms. Moreover, the total magnetic field remains ≳10<sup>14<sup/> G for periods of ≲60 ms. Thus, our results suggest that our scenario is promising to form classical fast-rotating magnetars and magnetars with weaker magnetic dipoles for slower rotations. We offer a calibration of the analytical scaling laws based on our simulations, with a dimensionless normalisation factor of the order of 10<sup>−2<sup/>. As the Tayler-Spruit dynamo is often invoked for the angular momentum transport in stellar radiative zones, our results are of particular significance to asteroseismology as well.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"33 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653541","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 : 2025-03-18DOI: 10.1051/0004-6361/202452634
Federico M. Vincentelli, Teo Muñoz-Darias
Quantifying the variability, measured as the root mean square (rms), of accreting systems as a function of energy is a powerful tool for constraining the physical properties of these objects. Here, we present the first application of this method to optical spectra of low-mass X-ray binaries. We use high-time-resolution data of the black hole transient V404 Cygni, obtained with the Gran Telescopio Canarias during its 2015 outburst. During this event, conspicuous wind-related features, such as P-Cygni profiles, were detected in the flux spectra. We find that rms spectra are rich in spectral features, although they are typically morphologically different from their flux counterparts. Specifically, we typically observe absorption components in correspondence to the presence of emission lines in the flux spectra. Similarly, when analysing segments with significant variability in the optical flux, P-Cygni line profiles appear inverted in the rms spectra (i.e., enhanced variability in the blue-shifted region, accompanied by a decrease in that associated with the red component). We discuss the possible origin of these features, which resemble those found in other objects, such as active galactic nuclei. Finally, we highlight the potential of this technique for future searches for wind-type outflows in accreting compact objects.
{"title":"Accretion disc winds imprint distinct signatures in the optical variability spectrum of black hole transients","authors":"Federico M. Vincentelli, Teo Muñoz-Darias","doi":"10.1051/0004-6361/202452634","DOIUrl":"https://doi.org/10.1051/0004-6361/202452634","url":null,"abstract":"Quantifying the variability, measured as the root mean square (rms), of accreting systems as a function of energy is a powerful tool for constraining the physical properties of these objects. Here, we present the first application of this method to optical spectra of low-mass X-ray binaries. We use high-time-resolution data of the black hole transient V404 Cygni, obtained with the <i>Gran Telescopio Canarias<i/> during its 2015 outburst. During this event, conspicuous wind-related features, such as P-Cygni profiles, were detected in the flux spectra. We find that rms spectra are rich in spectral features, although they are typically morphologically different from their flux counterparts. Specifically, we typically observe absorption components in correspondence to the presence of emission lines in the flux spectra. Similarly, when analysing segments with significant variability in the optical flux, P-Cygni line profiles appear inverted in the rms spectra (i.e., enhanced variability in the blue-shifted region, accompanied by a decrease in that associated with the red component). We discuss the possible origin of these features, which resemble those found in other objects, such as active galactic nuclei. Finally, we highlight the potential of this technique for future searches for wind-type outflows in accreting compact objects.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"88 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653673","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 : 2025-03-18DOI: 10.1051/0004-6361/202452732
J. A. Mansour, L. J. Liivamägi, A. Tamm, J. Laur, R. Abramo, E. Tempel, R. Kipper, A. Hernán-Caballero, V. Marra, J. Alcaniz, N. Benitez, S. Bonoli, S. Carneiro, J. Cenarro, D. Cristóbal-Hornillos, R. Dupke, A. Ederoclite, C. Hernández-Monteagudo, C. López-Sanjuan, A. Marín-Franch, C. M. de Oliveira, M. Moles, L. Sodré Jr, K. Taylor, J. Varela, H. Vázquez Ramió
Aims. We investigated the impact of photometric redshift errors in the ongoing Javalambre Physics of the Accelerating Universe Astrophysical Survey (J-PAS) on void identification and void properties using a watershed-based method. Our aim is to assess the recovery of individual voids and the overall void environment.Methods. We created galaxy mock catalogues for a redshift of z = 0.1, using the IllustrisTNG300-1 simulation and defining two datasets: an ideal sample (mr < 21 mag) and a perturbed sample with the Z-coordinate errors mimicking J-PAS’s line-of-sight errors, derived from the precursor miniJPAS survey data. We identified voids using the watershed algorithm ZOBOV.Results. We found 1065 voids in the ideal sample and 2558 voids in the perturbed sample. The perturbed sample voids have, on average, smaller sizes and denser interiors. We filtered out voids based on density and radius to eliminate overdense and small spurious instances. The stacked density profile of filtered voids in the perturbed sample remains close to the average density, even at the boundary peak, indicating a strong blurring of structures by the redshift errors. The number of the ideal sample voids for which at least 50% of the volume is recovered by a void in the perturbed sample is 53 (29 for the filtered sample). The volume occupied by these voids is less than 10% of the simulation volume. Merging voids in the perturbed sample marginally improves the recovery. The overall volumes defined as voids in the two samples have an overlap of 80%, making up 61% of the simulation box volume.Conclusions. While some statistical properties of voids might be recovered sufficiently well, the watershed algorithms may not be optimal for recovering the large-scale structure voids if they are applied directly to photometric redshift survey data.
{"title":"The J-PAS survey: The effect of photometric redshift errors on cosmic voids","authors":"J. A. Mansour, L. J. Liivamägi, A. Tamm, J. Laur, R. Abramo, E. Tempel, R. Kipper, A. Hernán-Caballero, V. Marra, J. Alcaniz, N. Benitez, S. Bonoli, S. Carneiro, J. Cenarro, D. Cristóbal-Hornillos, R. Dupke, A. Ederoclite, C. Hernández-Monteagudo, C. López-Sanjuan, A. Marín-Franch, C. M. de Oliveira, M. Moles, L. Sodré Jr, K. Taylor, J. Varela, H. Vázquez Ramió","doi":"10.1051/0004-6361/202452732","DOIUrl":"https://doi.org/10.1051/0004-6361/202452732","url":null,"abstract":"<i>Aims.<i/> We investigated the impact of photometric redshift errors in the ongoing Javalambre Physics of the Accelerating Universe Astrophysical Survey (J-PAS) on void identification and void properties using a watershed-based method. Our aim is to assess the recovery of individual voids and the overall void environment.<i>Methods.<i/> We created galaxy mock catalogues for a redshift of <i>z<i/> = 0.1, using the IllustrisTNG300-1 simulation and defining two datasets: an <i>ideal<i/> sample (<i>m<i/><sub><i>r<i/><sub/> < 21 mag) and a <i>perturbed<i/> sample with the Z-coordinate errors mimicking J-PAS’s line-of-sight errors, derived from the precursor miniJPAS survey data. We identified voids using the watershed algorithm ZOBOV.<i>Results.<i/> We found 1065 voids in the <i>ideal<i/> sample and 2558 voids in the <i>perturbed<i/> sample. The <i>perturbed<i/> sample voids have, on average, smaller sizes and denser interiors. We filtered out voids based on density and radius to eliminate overdense and small spurious instances. The stacked density profile of filtered voids in the <i>perturbed<i/> sample remains close to the average density, even at the boundary peak, indicating a strong blurring of structures by the redshift errors. The number of the <i>ideal<i/> sample voids for which at least 50% of the volume is recovered by a void in the <i>perturbed<i/> sample is 53 (29 for the filtered sample). The volume occupied by these voids is less than 10% of the simulation volume. Merging voids in the <i>perturbed<i/> sample marginally improves the recovery. The overall volumes defined as voids in the two samples have an overlap of 80%, making up 61% of the simulation box volume.<i>Conclusions.<i/> While some statistical properties of voids might be recovered sufficiently well, the watershed algorithms may not be optimal for recovering the large-scale structure voids if they are applied directly to photometric redshift survey data.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"91 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653542","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 : 2025-03-18DOI: 10.1051/0004-6361/202453482
M. Loriga, C. Pallanca, F. R. Ferraro, E. Dalessandro, B. Lanzoni, M. Cadelano, L. Origlia, C. Fanelli, D. Geisler, S. Villanova
This work consists of the first detailed photometric study of Terzan 6, one of the least known globular clusters in the Galactic bulge. Through the analysis of high angular resolution and multiwavelength data obtained from adaptive optics corrected and space observations, we built deep, optical and near-infrared color-magnitude diagrams reaching ≈4 magnitudes below the main-sequence turnoff. Taking advantage of four different epochs of observations, we measured precise relative proper motions for a large sample of stars, from which cluster members have been solidly distinguished from Galactic field interlopers. A noncanonical reddening law (with RV = 2.85) and high-resolution differential reddening map, with color excess variations up to δE(B − V) ≈ 0.8 mag, have been derived in the direction of the system. According to these findings, new values for the extinction and distance modulus have been obtained: E(B − V) = 2.36 ± 0.05 and (m − M)0 = 14.46 ± 0.10 (corresponding to d = 7.8 ± 0.3 kpc), respectively. We also provide the first determinations of the cluster center and projected density profile from resolved star counts. The center is offset by more than 7″ to the east from the literature value, and the structural parameters obtained from the King model fitting to the density profile indicate that Terzan 6 is in an advanced stage of its dynamical evolution, with a large value for the concentration parameter (c = 1.94−0.26+0.24) and a small core radius (rc = 2.6−0.7+0.09 arcsec). We also determined the absolute age of the system, finding t = 13 ± 1 Gyr, in agreement with the old ages found for the globular clusters in the Galactic bulge. From the redetermination of the absolute magnitude of the red giant branch bump and the recent estimate of the cluster global metallicity, we find that Terzan 6 nicely matches the tight relation between these two parameters drawn by the Galactic globular cluster population.
{"title":"The bulge globular cluster Terzan 6 as seen from multi-conjugate adaptive optics and HST★","authors":"M. Loriga, C. Pallanca, F. R. Ferraro, E. Dalessandro, B. Lanzoni, M. Cadelano, L. Origlia, C. Fanelli, D. Geisler, S. Villanova","doi":"10.1051/0004-6361/202453482","DOIUrl":"https://doi.org/10.1051/0004-6361/202453482","url":null,"abstract":"This work consists of the first detailed photometric study of Terzan 6, one of the least known globular clusters in the Galactic bulge. Through the analysis of high angular resolution and multiwavelength data obtained from adaptive optics corrected and space observations, we built deep, optical and near-infrared color-magnitude diagrams reaching ≈4 magnitudes below the main-sequence turnoff. Taking advantage of four different epochs of observations, we measured precise relative proper motions for a large sample of stars, from which cluster members have been solidly distinguished from Galactic field interlopers. A noncanonical reddening law (with <i>R<i/><sub><i>V<i/><sub/> = 2.85) and high-resolution differential reddening map, with color <i>excess<i/> variations up to <i>δE<i/>(<i>B<i/> − <i>V<i/>) ≈ 0.8 mag, have been derived in the direction of the system. According to these findings, new values for the extinction and distance modulus have been obtained: <i>E<i/>(<i>B<i/> − <i>V<i/>) = 2.36 ± 0.05 and (<i>m<i/> − <i>M<i/>)<sub>0<sub/> = 14.46 ± 0.10 (corresponding to <i>d<i/> = 7.8 ± 0.3 kpc), respectively. We also provide the first determinations of the cluster center and projected density profile from resolved star counts. The center is offset by more than 7″ to the east from the literature value, and the structural parameters obtained from the King model fitting to the density profile indicate that Terzan 6 is in an advanced stage of its dynamical evolution, with a large value for the concentration parameter (<i>c<i/> = 1.94<sub>−0.26<sub/><sup>+0.24<sup/>) and a small core radius (<i>r<sub>c<sub/><i/> = 2.6<sub>−0.7<sub/><sup>+0.09<sup/> arcsec). We also determined the absolute age of the system, finding <i>t<i/> = 13 ± 1 Gyr, in agreement with the old ages found for the globular clusters in the Galactic bulge. From the redetermination of the absolute magnitude of the red giant branch bump and the recent estimate of the cluster global metallicity, we find that Terzan 6 nicely matches the tight relation between these two parameters drawn by the Galactic globular cluster population.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"91 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653603","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 : 2025-03-18DOI: 10.1051/0004-6361/202451785
Brooke Polak, Mordecai-Mark Mac Low, Ralf S. Klessen, Simon Portegies Zwart, Eric P. Andersson, Sabrina M. Appel, Claude Cournoyer-Cloutier, Simon C. O. Glover, Stephen L. W. McMillan
Mass segregation is seen in many star clusters, but whether massive stars form in the center of a cluster or migrate there dynamically is still debated. N-body simulations show that early dynamical mass segregation is possible when sub-clusters merge to form a dense core with a small crossing time. However, the effect of gas dynamics on both the formation and dynamics of the stars could inhibit the formation of the dense core. We aim to study the dynamical mass segregation of star cluster models that include gas dynamics and selfconsistently form stars from the dense substructure in the gas. Our models use the TORCH framework, which is based on AMUSE and includes stellar and magnetized gas dynamics, as well as stellar evolution and feedback from radiation, stellar winds, and supernovae. Our models consist of three star clusters forming from initial turbulent spherical clouds of mass 104, 105, 106 M⊙ and radius 11.7 pc that have final stellar masses of 3.6 × 103 M⊙, 6.5 × 104 M⊙, and 8.9 × 105 M⊙, respectively. There is no primordial mass segregation in the model by construction. All three clusters become dynamically mass segregated at early times via collapse confirming that this mechanism occurs within sub-clusters forming directly out of the dense substructure in the gas. The dynamics of the embedded gas and stellar feedback do not inhibit the collapse of the cluster. We find that each model cluster becomes mass segregated within 2 Myr of the onset of star formation, reaching the levels observed in young clusters in the Milky Way. However, we note that the exact values are highly time-variable during these early phases of evolution. Massive stars that segregate to the center during core collapse are likely to be dynamically ejected, a process that can decrease the overall level of mass segregation again.
{"title":"Massive star cluster formation","authors":"Brooke Polak, Mordecai-Mark Mac Low, Ralf S. Klessen, Simon Portegies Zwart, Eric P. Andersson, Sabrina M. Appel, Claude Cournoyer-Cloutier, Simon C. O. Glover, Stephen L. W. McMillan","doi":"10.1051/0004-6361/202451785","DOIUrl":"https://doi.org/10.1051/0004-6361/202451785","url":null,"abstract":"Mass segregation is seen in many star clusters, but whether massive stars form in the center of a cluster or migrate there dynamically is still debated. <i>N<i/>-body simulations show that early dynamical mass segregation is possible when sub-clusters merge to form a dense core with a small crossing time. However, the effect of gas dynamics on both the formation and dynamics of the stars could inhibit the formation of the dense core. We aim to study the dynamical mass segregation of star cluster models that include gas dynamics and selfconsistently form stars from the dense substructure in the gas. Our models use the TORCH framework, which is based on AMUSE and includes stellar and magnetized gas dynamics, as well as stellar evolution and feedback from radiation, stellar winds, and supernovae. Our models consist of three star clusters forming from initial turbulent spherical clouds of mass 10<sup>4<sup/>, 10<sup>5<sup/>, 10<sup>6<sup/> M<sub>⊙<sub/> and radius 11.7 pc that have final stellar masses of 3.6 × 10<sup>3<sup/> M<sub>⊙<sub/>, 6.5 × 10<sup>4<sup/> M<sub>⊙<sub/>, and 8.9 × 10<sup>5<sup/> M<sub>⊙<sub/>, respectively. There is no primordial mass segregation in the model by construction. All three clusters become dynamically mass segregated at early times via collapse confirming that this mechanism occurs within sub-clusters forming directly out of the dense substructure in the gas. The dynamics of the embedded gas and stellar feedback do not inhibit the collapse of the cluster. We find that each model cluster becomes mass segregated within 2 Myr of the onset of star formation, reaching the levels observed in young clusters in the Milky Way. However, we note that the exact values are highly time-variable during these early phases of evolution. Massive stars that segregate to the center during core collapse are likely to be dynamically ejected, a process that can decrease the overall level of mass segregation again.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"33 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653537","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 : 2025-03-18DOI: 10.1051/0004-6361/202450356
C. Bordiu, S. Riggi, F. Bufano, F. Cavallaro, T. Cecconello, F. Camilo, G. Umana, W. D. Cotton, M. A. Thompson, M. Bietenholz, S. Goedhart, L. D. Anderson, C. S. Buemi, J. O. Chibueze, A. Ingallinera, P. Leto, S. Loru, M. Mutale, A. Rigby, C. Trigilio, G. M. Williams
We present a catalogue of extended radio sources from the SARAO MeerKAT Galactic Plane Survey (SMGPS). Compiled from 56 survey tiles and covering approximately 500 deg2 across the first, third, and fourth Galactic quadrants, the catalogue includes 16 534 extended and diffuse sources with areas larger than 5 synthesised beams. Of them, 3891 (24% of the total) are confidently associated with known Galactic radio-emitting objects in the literature, such as HII regions, supernova remnants, planetary nebulae, luminous blue variables, and Wolf-Rayet stars. A significant fraction of the remaining sources, 5462 (33%), are candidate extragalactic sources, while 7181 (43%) remain unclassified. Isolated radio filaments are excluded from the catalogue. The diversity of extended sources underscores MeerKAT’s contribution to the completeness of censuses of Galactic radio emitters, and its potential for new scientific discoveries. For the catalogued sources, we derived basic positional and morphological parameters, as well as flux density estimates, using standard aperture photometry. This paper describes the methods followed to generate the catalogue from the original SMGPS tiles, detailing the source extraction, characterisation, and crossmatching procedures. Additionally, we analyse the statistical properties of the catalogued populations.
{"title":"The SARAO MeerKAT Galactic Plane Survey extended source catalogue","authors":"C. Bordiu, S. Riggi, F. Bufano, F. Cavallaro, T. Cecconello, F. Camilo, G. Umana, W. D. Cotton, M. A. Thompson, M. Bietenholz, S. Goedhart, L. D. Anderson, C. S. Buemi, J. O. Chibueze, A. Ingallinera, P. Leto, S. Loru, M. Mutale, A. Rigby, C. Trigilio, G. M. Williams","doi":"10.1051/0004-6361/202450356","DOIUrl":"https://doi.org/10.1051/0004-6361/202450356","url":null,"abstract":"We present a catalogue of extended radio sources from the SARAO MeerKAT Galactic Plane Survey (SMGPS). Compiled from 56 survey tiles and covering approximately 500 deg<sup>2<sup/> across the first, third, and fourth Galactic quadrants, the catalogue includes 16 534 extended and diffuse sources with areas larger than 5 synthesised beams. Of them, 3891 (24% of the total) are confidently associated with known Galactic radio-emitting objects in the literature, such as HII regions, supernova remnants, planetary nebulae, luminous blue variables, and Wolf-Rayet stars. A significant fraction of the remaining sources, 5462 (33%), are candidate extragalactic sources, while 7181 (43%) remain unclassified. Isolated radio filaments are excluded from the catalogue. The diversity of extended sources underscores MeerKAT’s contribution to the completeness of censuses of Galactic radio emitters, and its potential for new scientific discoveries. For the catalogued sources, we derived basic positional and morphological parameters, as well as flux density estimates, using standard aperture photometry. This paper describes the methods followed to generate the catalogue from the original SMGPS tiles, detailing the source extraction, characterisation, and crossmatching procedures. Additionally, we analyse the statistical properties of the catalogued populations.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"8 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653668","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 : 2025-03-18DOI: 10.1051/0004-6361/202452960
Jiangwei Xu, Jinchen Jiang, Heng Xu, Bojun Wang, Zihan Xue, Siyuan Chen, Yanjun Guo, R. Nicolas Caballero, Kejia Lee, Jianping Yuan, Yonghua Xu, Jingbo Wang, Longfei Hao, Zhixuan Li, Yuxiang Huang, Zezhong Xu, Jintao Luo, Jinlin Han, Peng Jiang, Zhiqiang Shen, Min Wang, Na Wang, Renxin Xu, Xiangping Wu, Lei Qian, Youling Yue, Xin Guan, Menglin Huang, Chun Sun, Yan Zhu
We present polarization pulse profiles for 56 millisecond pulsars (MSPs) monitored by the Chinese Pulsar Timing Array (CPTA) collaboration using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The observations centered at 1.25 GHz with a raw bandwidth of 500 MHz. Due to the high sensitivity (∼16 K/Jy) of the FAST telescope and our long integration time, the high signal-to-noise ratio polarization profiles show features hardly detected before. Among 56 pulsars, the polarization profiles of PSRs J0406+3039, J1327+3423, and J2022+2534 were not previously reported. 80% of MSPs in the sample show weak components below 3% of peak flux, 25% of pulsars show interpulse-like structures, and most pulsars show linear polarization position angle jumps. Six pulsars seem to be emitting for full rotation phase, with another thirteen pulsars being good candidates for such a 360° radiator. We find that the distribution of the polarization percentage in our sample is compatible with the normal pulsar distribution. Our detailed evaluation of the MSP polarization properties suggests that the wave propagation effects in the pulsar magnetosphere are important in shaping the MSP polarization pulse profiles.
{"title":"The Chinese pulsar timing array data release I","authors":"Jiangwei Xu, Jinchen Jiang, Heng Xu, Bojun Wang, Zihan Xue, Siyuan Chen, Yanjun Guo, R. Nicolas Caballero, Kejia Lee, Jianping Yuan, Yonghua Xu, Jingbo Wang, Longfei Hao, Zhixuan Li, Yuxiang Huang, Zezhong Xu, Jintao Luo, Jinlin Han, Peng Jiang, Zhiqiang Shen, Min Wang, Na Wang, Renxin Xu, Xiangping Wu, Lei Qian, Youling Yue, Xin Guan, Menglin Huang, Chun Sun, Yan Zhu","doi":"10.1051/0004-6361/202452960","DOIUrl":"https://doi.org/10.1051/0004-6361/202452960","url":null,"abstract":"We present polarization pulse profiles for 56 millisecond pulsars (MSPs) monitored by the Chinese Pulsar Timing Array (CPTA) collaboration using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The observations centered at 1.25 GHz with a raw bandwidth of 500 MHz. Due to the high sensitivity (∼16 K/Jy) of the FAST telescope and our long integration time, the high signal-to-noise ratio polarization profiles show features hardly detected before. Among 56 pulsars, the polarization profiles of PSRs J0406+3039, J1327+3423, and J2022+2534 were not previously reported. 80% of MSPs in the sample show weak components below 3% of peak flux, 25% of pulsars show interpulse-like structures, and most pulsars show linear polarization position angle jumps. Six pulsars seem to be emitting for full rotation phase, with another thirteen pulsars being good candidates for such a 360° radiator. We find that the distribution of the polarization percentage in our sample is compatible with the normal pulsar distribution. Our detailed evaluation of the MSP polarization properties suggests that the wave propagation effects in the pulsar magnetosphere are important in shaping the MSP polarization pulse profiles.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"17 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653669","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 : 2025-03-18DOI: 10.1051/0004-6361/202450236
Kundan Kadam, Eduard Vorobyov, Peter Woitke, Shantanu Basu, Sierk van Terwisga
Context. Canonically, a protoplanetary disk is thought to undergo (gravito-)viscous evolution wherein the angular momentum of the accreting material is transported outward. However, several lines of reasoning suggest that the turbulent viscosity in a typical protoplanetary disk is insufficient to drive the observed accretion rates. An emerging paradigm suggests that radially extended magnetic disk winds, which transport angular momentum vertically, may play a crucial role in disk evolution.Aims. We propose a global model of magnetic wind-driven accretion for the evolution of protoplanetary disks in the thin-disk limit based on the insights gained from local shearing box simulations. In this paper, we aim to develop this model and constrain the model parameters with the help of theoretical expectations and through comparison with observations.Methods. The magnetic wind is characterized with the associated loss of angular momentum and mass, and we modeled these with fitting formulae that depend on the local disk conditions and stellar properties. We incorporated the disk winds self-consistently in the numerical magnetohydrodynamic code FEOSAD and studied the formation and long-term evolution of protoplanetary disks. We included disk self-gravity and an adaptive turbulent α that depends on the local ionization balance, while the co-evolution of a two-part dusty component was also considered. We obtained synthetic observations via detailed modeling with the radiation thermo-chemical code PRODIMO.Results. The models that include disk winds satisfy the general expectations from both theory and observations. The disk wind parameters can be guided by observational constraints, and the synthetic observations resulting from such a model compare favorably with the selected ALMA survey data of Class II disks. The proposed magnetic disk wind model is a significant step forward in the direction of representing a more complete disk evolution, wherein the disk experiences concurrent torques from viscous, gravitational, and magnetic wind processes.
{"title":"Magnetic disk winds in protoplanetary disks","authors":"Kundan Kadam, Eduard Vorobyov, Peter Woitke, Shantanu Basu, Sierk van Terwisga","doi":"10.1051/0004-6361/202450236","DOIUrl":"https://doi.org/10.1051/0004-6361/202450236","url":null,"abstract":"<i>Context.<i/> Canonically, a protoplanetary disk is thought to undergo (gravito-)viscous evolution wherein the angular momentum of the accreting material is transported outward. However, several lines of reasoning suggest that the turbulent viscosity in a typical protoplanetary disk is insufficient to drive the observed accretion rates. An emerging paradigm suggests that radially extended magnetic disk winds, which transport angular momentum vertically, may play a crucial role in disk evolution.<i>Aims.<i/> We propose a global model of magnetic wind-driven accretion for the evolution of protoplanetary disks in the thin-disk limit based on the insights gained from local shearing box simulations. In this paper, we aim to develop this model and constrain the model parameters with the help of theoretical expectations and through comparison with observations.<i>Methods.<i/> The magnetic wind is characterized with the associated loss of angular momentum and mass, and we modeled these with fitting formulae that depend on the local disk conditions and stellar properties. We incorporated the disk winds self-consistently in the numerical magnetohydrodynamic code FEOSAD and studied the formation and long-term evolution of protoplanetary disks. We included disk self-gravity and an adaptive turbulent α that depends on the local ionization balance, while the co-evolution of a two-part dusty component was also considered. We obtained synthetic observations via detailed modeling with the radiation thermo-chemical code PRODIMO.<i>Results.<i/> The models that include disk winds satisfy the general expectations from both theory and observations. The disk wind parameters can be guided by observational constraints, and the synthetic observations resulting from such a model compare favorably with the selected ALMA survey data of Class II disks. The proposed magnetic disk wind model is a significant step forward in the direction of representing a more complete disk evolution, wherein the disk experiences concurrent torques from viscous, gravitational, and magnetic wind processes.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"20 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653891","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 : 2025-03-18DOI: 10.1051/0004-6361/202453224
M. V. Zanchettin, C. Ramos Almeida, A. Audibert, J. A. Acosta-Pulido, P. H. Cezar, E. Hicks, A. Lapi, J. Mullaney
We present seeing-limited (0.8″) near-infrared integral field spectroscopy data of the type-2 quasars, QSO2s, SDSS J135646.10+102609.0 (J1356) and SDSS J143029.89+133912.1 (J1430, the Teacup), both belonging to the Quasar Feedback, QSOFEED, sample. The nuclear K-band spectra (1.95–2.45 μm) of these radio-quiet QSO2s reveal several H2 emission lines, indicative of the presence of a warm molecular gas reservoir (T ≥ 1000 K). We measure nuclear masses of MH2 = 5.9, 4.1, and 1.5 × 103 M⊙ in the inner 0.8″ diameter region of the Teacup (∼1.3 kpc), J1356 north (J1356N), and south nuclei (∼1.8 kpc), respectively. The total warm H2 mass budget is ∼4.5 × 104 M⊙ in the Teacup and ∼1.3 × 104 M⊙ in J1356N, implying warm-to-cold molecular gas ratios of 10−6. The warm molecular gas kinematics, traced with the H21-0S(1) and S(2) emission lines, is consistent with that of the cold molecular phase, traced by ALMA CO emission at higher angular resolution (0.2″ and 0.6″). In J1430, we detect the blue- and red-shifted sides of a compact warm molecular outflow extending up to 1.9 kpc and with velocities of 450 km s−1. In J1356 only the red-shifted side is detected, with a radius of up to 2.0 kpc and velocity of 370 km s−1. The outflow masses are 2.6 and 1.5 × 103 M⊙ for the Teacup and J1356N, and the warm-to-cold gas ratios in the outflows are 0.8 and 1 × 10−4, implying that the cold molecular phase dominates the mass budget. We measure warm molecular mass outflow rates of 6.2 and 2.9 × 10−4 M⊙ yr−1 for the Teacup and J1356N, which are approximately 0.001% of the total mass outflow rate (ionized + cold and warm molecular). We find an enhancement of velocity dispersion in the H21-0S(1) residual dispersion map of the Teacup, both along and perpendicular to the compact radio jet direction. This enhanced turbulence can be reproduced by simulations of jet-ISM interactions.
{"title":"Unveiling the warm molecular outflow component of type-2 quasars with SINFONI","authors":"M. V. Zanchettin, C. Ramos Almeida, A. Audibert, J. A. Acosta-Pulido, P. H. Cezar, E. Hicks, A. Lapi, J. Mullaney","doi":"10.1051/0004-6361/202453224","DOIUrl":"https://doi.org/10.1051/0004-6361/202453224","url":null,"abstract":"We present seeing-limited (0.8″) near-infrared integral field spectroscopy data of the type-2 quasars, QSO2s, SDSS J135646.10+102609.0 (J1356) and SDSS J143029.89+133912.1 (J1430, the Teacup), both belonging to the Quasar Feedback, QSOFEED, sample. The nuclear <i>K<i/>-band spectra (1.95–2.45 μm) of these radio-quiet QSO2s reveal several H<sub>2<sub/> emission lines, indicative of the presence of a warm molecular gas reservoir (<i>T<i/> ≥ 1000 K). We measure nuclear masses of <i>M<i/><sub>H<sub>2<sub/><sub/> = 5.9, 4.1, and 1.5 × 10<sup>3<sup/> M<sub>⊙<sub/> in the inner 0.8″ diameter region of the Teacup (∼1.3 kpc), J1356 north (J1356N), and south nuclei (∼1.8 kpc), respectively. The total warm H<sub>2<sub/> mass budget is ∼4.5 × 10<sup>4<sup/> M<sub>⊙<sub/> in the Teacup and ∼1.3 × 10<sup>4<sup/> M<sub>⊙<sub/> in J1356N, implying warm-to-cold molecular gas ratios of 10<sup>−6<sup/>. The warm molecular gas kinematics, traced with the H<sub>2<sub/>1-0S(1) and S(2) emission lines, is consistent with that of the cold molecular phase, traced by ALMA CO emission at higher angular resolution (0.2″ and 0.6″). In J1430, we detect the blue- and red-shifted sides of a compact warm molecular outflow extending up to 1.9 kpc and with velocities of 450 km s<sup>−1<sup/>. In J1356 only the red-shifted side is detected, with a radius of up to 2.0 kpc and velocity of 370 km s<sup>−1<sup/>. The outflow masses are 2.6 and 1.5 × 10<sup>3<sup/> M<sub>⊙<sub/> for the Teacup and J1356N, and the warm-to-cold gas ratios in the outflows are 0.8 and 1 × 10<sup>−4<sup/>, implying that the cold molecular phase dominates the mass budget. We measure warm molecular mass outflow rates of 6.2 and 2.9 × 10<sup>−4<sup/> M<sub>⊙<sub/> yr<sup>−1<sup/> for the Teacup and J1356N, which are approximately 0.001% of the total mass outflow rate (ionized + cold and warm molecular). We find an enhancement of velocity dispersion in the H<sub>2<sub/>1-0S(1) residual dispersion map of the Teacup, both along and perpendicular to the compact radio jet direction. This enhanced turbulence can be reproduced by simulations of jet-ISM interactions.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"70 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653667","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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