Astronomy & Astrophysics最新文献

{"title":"Confronting sparse Gaia DR3 photometry with TESS for a sample of around 60 000 OBAF-type pulsators★★★","authors":"Daniel Hey, Conny Aerts","doi":"10.1051/0004-6361/202450489","DOIUrl":"https://doi.org/10.1051/0004-6361/202450489","url":null,"abstract":"<i>Context.<i/> The <i>Gaia<i/> mission has delivered hundreds of thousands of variable star light curves in multiple wavelengths. Recent work demonstrates that these light curves can be used to identify (non-)radial pulsations in OBAF-type stars, despite their irregular cadence and low light curve precision, of the order of a few millimagnitudes. With the considerably more precise TESS photometry, we revisited these candidate pulsators to conclusively ascertain the nature of their variability.<i>Aims.<i/> We seek to re-classify the <i>Gaia<i/> light curves with the first two years of TESS photometry for a sample of 58 970 <i>p<i/>- and <i>g<i/>-mode pulsators, encompassing <i>γ<i/> Dor, <i>δ<i/> Scuti, slowly pulsating B, and <i>β<i/> Cep variables. From the TESS data, we seek to assess the quality of <i>Gaia<i/>’s classification of non-radial pulsators, which is based on sparse, years-long light curves of millimagnitude precision. We also supply four new catalogues containing the confirmed pulsators, along with their dominant and secondary pulsation frequencies, the number of independent mode frequencies, and a ranking according to their usefulness for future asteroseismic ensemble analysis.<i>Methods.<i/> We first analysed the TESS light curves independent of their <i>Gaia<i/> classification by pre-whitening all dominant pulsation modes down to a 1% false alarm probability. Using this, in combination with a feature-based random forest classifier, we identified different variability types across the sample.<i>Results.<i/> We find that the <i>Gaia<i/> photometry is exceptionally accurate for detecting the dominant and secondary frequencies, reaching approximately 80% accuracy in frequency for <i>p<i/>- and <i>g<i/>-mode pulsators. The majority of <i>Gaia<i/> classifications are consistent with the classifications from the TESS data, illustrating the power of the low-cadence <i>Gaia<i/> photometry for pulsation studies. We find that the sample of <i>g<i/>-mode pulsators forms a continuous group of variable stars along the main sequence across B, A, and F spectral types, implying that the mode excitation mechanisms for all these pulsators need to be updated with improved physics. Finally, we provide a rank-ordered table of pulsators according to their asteroseismic potential for follow-up studies, based on the number of sectors they have been observed in, their classification probability, and the number of independent modes found in the TESS light curves from the nominal mission.<i>Conclusions.<i/> Our catalogue offers a major increase in the number of confirmed <i>g<i/>-mode pulsators with an identified dominant mode suitable for follow-up TESS ensemble asteroseismology of such stars.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973936","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}

{"title":"Formation of planetary atmospheres","authors":"Ryushi Miyayama, Hiroshi Kobayashi","doi":"10.1051/0004-6361/202450177","DOIUrl":"https://doi.org/10.1051/0004-6361/202450177","url":null,"abstract":"To investigate impact vaporization for planetary atmosphere formation, we have studied the thermodynamic state generated by the shock wave due to a high-velocity impact, called the shock field. We have carried out iSALE simulations for high-velocity vertical impacts using ANEOS for an equation-of-state (EoS) model. To understand the shock fields obtained from simulations, we have investigated the contribution of the thermal and cold terms in the EoS model on the Hugoniot curves. Although the thermal and cold terms are important for the pressure, the internal energy is mainly determined by the thermal term. We thus assume a simple EoS determined by the thermal term and then analytically derive the shock internal-energy field, which reproduces the results of simulations well. Using the analytical solution of internal energy and the Hugoniot curve, we have derived the shock pressure field analytically as well. The analytical solutions for internal energy and pressure are valid even for impact velocities as low as the sound speed. The solution is good for the vertical direction or within the angles of about 60 degrees. We have applied the solution to impact vaporization for the formation of planetary atmospheres. This gives good estimation of reformation of the planetary atmospheres of Earth sized planet.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225771","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}

{"title":"GASTLI","authors":"L. Acuña, L. Kreidberg, M. Zhai, P. Mollière","doi":"10.1051/0004-6361/202450559","DOIUrl":"https://doi.org/10.1051/0004-6361/202450559","url":null,"abstract":"The metal mass fractions of gas giants are a powerful tool for constraining their formation mechanisms and evolution. The metal content is inferred by comparing mass and radius measurements with interior structure and evolution models. In the midst of the JWST, CHEOPS, TESS, and the forthcoming PLATO era, we are at the brink of obtaining unprecedented precision in radius, age, and atmospheric metallicity measurements. To prepare for this wealth of data, we present the GAS gianT modeL for Interiors (GASTLI), an easy-to-use, publicly available Python package. The code is optimized to rapidly calculate mass-radius relations, and radius and luminosity thermal evolution curves for a variety of envelope compositions and core mass fractions. Its applicability spans planets with masses of 17 <i>M<i/><sub>⊕<sub/> < <i>M <<i/> 6 <i>M<i/><sub>Jup<sub/>, and equilibrium temperatures of <i>T<i/><sub>eq<sub/> <i><<i/> 1000 K. The interior model is stratified in a core composed of water and rock, and an envelope constituted by H/He and metals (water). The interior is coupled to a grid of self-consistent, cloud-free atmospheric models to determine the atmospheric and boundary interior temperature, as well as the contribution of the atmosphere to the total radius. We successfully validate GASTLI by comparing it to previous work and data of the gas giants of the Solar System and Neptune. We also test GASTLI on the Neptune-mass exoplanet HAT-P-26 b, finding a bulk metal mass fraction of between 0.60 and 0.78 and a core mass of 8.5–14.4 <i>M<i/><sub>⊕<sub/>. Finally, we explore the impact of different equations of state and assumptions, such as C/O ratio and transit pressure, in the estimation of bulk metal mass fraction. These differences between interior models entail a change in radius of up to 2.5% for Jupiter-mass planets, but of more than 10% for Neptune-mass. These are equivalent to variations in core mass fraction of 0.07, or 0.10 in envelope metal mass fraction.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891838","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}

{"title":"A dusty magnetospheric stream explaining the light curves of the dipper objects: Finding a new inclination threshold to produce dippers","authors":"Erick Nagel, Jerome Bouvier, Adrián E. Duarte","doi":"10.1051/0004-6361/202450085","DOIUrl":"https://doi.org/10.1051/0004-6361/202450085","url":null,"abstract":"<i>Context<i/>. The so-called “dippers” are young stellar objects that exhibit dimming episodes in their optical light curves. The common interpretation for the occurrence of these dips is that dusty regions periodically or quasi-periodically cross the line of sight toward the object.<i>Aims<i/>. We develop a model where we assume that these regions are located at the intersection of the magnetospheric stream with the disk. The stream is fed by gas and dust coming from the disk. As the material follows the magnetic field lines above the disk plane, it forms an opaque screen that partially blocks the stellar emission. The amount of extinction caused by the material crossing the line of sight depends on the abundance and location of the dust along the stream, which depends on the degree of dust evaporation due to the heating by the star.<i>Methods<i/>. We run hydrodynamical simulations of dusty accretion streams to produce synthetic dipper light curves for a sample of low-mass young stars still accreting from their disk according to evolutionary models. We compare the distribution of the light curve amplitudes between the synthetic sample and observed samples of dippers from various star-forming regions.<i>Results<i/>. Dust evaporation along the accretion column drives the distribution of photometric amplitudes. Our results suggest that most of the observed dippers correspond to systems seen at high inclination. However, dust survival within accretion columns may also produce dippers at lower inclination, down to about 45°. We find that the dust temperature arising from stellar irradiation should be increased by a factor 1.6 to find consistency between the fraction of dippers our model predicts in star-forming regions and the observed fraction of 20–30%.<i>Conclusions<i/>. Transient dust survival in accretion columns appear as an alternative (or complementary) mechanism to inner disk warp occultation in order to account for low-inclination dippers in star-forming regions.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891848","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}

{"title":"Dynamical formation of Gaia BH3 in the progenitor globular cluster of the ED-2 stream","authors":"Daniel Marín Pina, Sara Rastello, Mark Gieles, Kyle Kremer, Laura Fitzgerald, Bruno Rando Forastier","doi":"10.1051/0004-6361/202450460","DOIUrl":"https://doi.org/10.1051/0004-6361/202450460","url":null,"abstract":"<i>Context.<i/> The star–black hole (S–BH) binary known as <i>Gaia<i/> BH3, discovered by the <i>Gaia<i/> Collaboration is chemically and kinematically associated with the metal-poor ED-2 stream in the Milky Way halo.<i>Aims.<i/> We explore the possibility that <i>Gaia<i/> BH3 was assembled dynamically in the progenitor globular cluster (GC) of the ED-2 stream.<i>Methods.<i/> We used a public suite of star-by-star dynamical Monte Carlo models to identify S–BH binaries in GCs with different initial masses and (half-mass) radii.<i>Results.<i/> We show that a likely progenitor of the ED-2 stream was a relatively low-mass (≲10<sup>5<sup/> <i>M<i/><sub>⊙<sub/>) GC with an initial half-mass radius of ∼4 pc. Such a GC can dynamically retain a large fraction of its BH population and dissolve on the orbit of ED-2. From the suite of models we find that GCs produce ∼3 − 30 S–BH binaries, approximately independently of initial GC mass and inversely correlated with initial cluster radius. Scaling the results to the Milky Way GC population, we find that ∼75% of the S–BH binaries formed in GCs are ejected from their host GC, all in the early phases of evolution (≲1 Gyr); these are expected to no longer be close to streams. The ∼25% of S–BH binaries retained until dissolution are expected to form part of streams, such that for an initial mass of the progenitor of ED-2 of a few 10<sup>4<sup/> <i>M<i/><sub>⊙<sub/>, we expect ∼2 − 3 S–BH to end up in the stream. GC models with metallicities similar to <i>Gaia<i/> BH3 (≲1% solar) include S–BH binaries with similar BH masses (≳30 <i>M<i/><sub>⊙<sub/>), orbital periods, and eccentricities.<i>Conclusion.<i/> We predict that the Galactic halo contains of order 10<sup>5<sup/> S–BH binaries that formed dynamically in GCs, a fraction of which may readily be detected in <i>Gaia<i/> DR4. The detection of these sources provides valuable tests of BH dynamics in clusters and their contribution to gravitational wave sources.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141857762","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}

{"title":"Periodic variable A-F spectral type stars in the southern TESS continuous viewing zone","authors":"M. Skarka, Z. Henzl","doi":"10.1051/0004-6361/202450711","DOIUrl":"https://doi.org/10.1051/0004-6361/202450711","url":null,"abstract":"<i>Aims<i/>. Our primary objective is to accurately identify and classify the variability of A-F stars in the southern continuous viewing zone of the TESS satellite. The brightness limit was set to 10 mag to ensure the utmost reliability of our results and allow for spectroscopic follow-up observations using small telescopes. We aim to compare our findings with existing catalogues of variable stars.<i>Methods<i/>. The light curves from TESS and their Fourier transform were used to manually classify stars in our sample. Cross-matching with other catalogues was performed to identify contaminants and false positives.<i>Results<i/>. We have identified 1171 variable stars (51% of the sample). Among these variable stars, 67% have clear classifications, which includes <i>δ<i/> Sct and <i>γ<i/> Dor pulsating stars and their hybrids, rotationally variables, and eclipsing binaries. We have provided examples of the typical representatives of variable stars and discussed the ambiguous cases. We found 20 pairs of stars with the same frequencies and identified the correct source of the variations. Additionally, we found that the variations in 12 other stars are caused by contamination from the light of faint nearby large-amplitude variable stars. To compare our sample with other variable star catalogues, we have defined two parameters reflecting the agreement in identification of variable stars and their classification. This comparison reveals intriguing disagreements in classification ranging from 52 to 100%. However, if we assume that stars without specific types are only marked as variable, then the agreement is relatively good, ranging from 57 to 85% (disagreement 15–43%). We have demonstrated that the TESS classification is superior to the classification based on other photometric surveys.<i>Conclusions<i/>. The classification of stellar variability is complex and requires careful consideration. Caution should be exercised when using catalogue classifications.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141857763","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}

{"title":"Dust properties and their variations in comet C/2013 X1 (PANSTARRS)","authors":"Olena Shubina, Evgenij Zubko, Valerii Kleshchonok, Oleksandra V. Ivanova, Marek Husárik, Gorden Videen","doi":"10.1051/0004-6361/202449145","DOIUrl":"https://doi.org/10.1051/0004-6361/202449145","url":null,"abstract":"<i>Context.<i/> We analyze the results of photometric monitoring of comet C/2013 X1 (PANSTARRS) from December 2015 until January 2016 obtained within <i>B, V<i/>, and <i>R<i/> Johnson–Cousins filters.<i>Aims.<i/> The main objective is to investigate the dust coma and to obtain the physical characteristics of its dust particles.<i>Methods.<i/> We analyzed our observations using model-agglomerated debris particles, and we constrained the microphysical properties of the dust in comet C/2013 X1 (PANSTARRS) on the pre-outburst and post-outburst epochs. Moreover, we applied a geometrical model to the images processed by digital filters to estimate the rotational period of the nucleus.<i>Results.<i/> Our campaign revealed a sharp increase in the comet brightness on January 1, 2016. The <i>B − V<i/> and <i>V − R<i/> colors calculated within an aperture size of 17 000 km appear to be mostly red, except for the outburst date. The dust production (<i>A f ρ<i/> proxy) and normalized spectral gradient <i>S′<i/> (<i>B − R<i/>) dramatically changed on January 2 as compared to what was seen in December 2015. According to this model, the C/2013 X1 coma was populated by 70% organic-matter particles by volume and by two types of silicate particles together, constituting the other 30%. One type of silicate particles was composed of Mg-rich silicates, whereas the other type was composed of both Mg-rich and Fe-poor silicates. Using the geometrical model, we estimate the nucleus rotational period to be (24.02 ± 0.02) h. We interpret the observed coma morphology by two jet structures, one structure that formed by the near-pole active area at a latitude of (85<sub>+5<sub/><sup>−3<sup/>)°, and the other structure formed by an active area at a latitude of (+40 ± 5)°.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141755430","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}

{"title":"The IACOB project","authors":"A. de Burgos, S. Simón-Díaz, M. A. Urbaneja, J. Puls","doi":"10.1051/0004-6361/202348808","DOIUrl":"https://doi.org/10.1051/0004-6361/202348808","url":null,"abstract":"<i>Context<i/>. Blue supergiants (BSGs) are key objects for understanding the evolution of massive stars, which play a crucial role in the evolution of galaxies. However, discrepancies between theoretical predictions and empirical observations have opened up important questions yet to be answered. Studying statistically significant and unbiased samples of these objects can help to improve the situation.<i>Aims<i/>. We perform a homogeneous and comprehensive quantitative spectroscopic analysis of a large sample of Galactic luminous blue stars (a majority of which are BSGs) from the IACOB spectroscopic database, providing crucial parameters to refine and improve theoretical evolutionary models.<i>Methods<i/>. We derived the projected rotational velocity (<i>υ<i/> sin <i>i<i/>) and macroturbulent broadening (<i>υ<i/><sub>mac<sub/>) using IACOB-BROAD, which combines Fourier transform and line-profile fitting techniques. We compared high-quality optical spectra with state-of-the-art simulations of massive star atmospheres computed with the FASTWIND code. This comparison allowed us to derive effective temperatures (<i>T<i/><sub>eff<sub/>), surface gravities (log <i>𝑔<i/>), microturbulences (<i>ξ<i/>), surface abundances of silicon and helium, and to assess the relevance of stellar winds through a wind-strength parameter (log <i>Q<i/>).<i>Results<i/>. We provide estimates and associated uncertainties of the above-mentioned quantities for the largest sample of Galactic luminous O9 to B5 stars spectroscopically analyzed to date, comprising 527 targets. We find a clear drop in the relative number of stars at T<sub>eff<sub/> ≈ 21 kK, coinciding with a scarcity of fast rotating stars below that temperature. We speculate that this feature (roughly corresponding to B2 spectral type) might be roughly delineating the location of the empirical terminal-age main sequence in the mass range between 15 and 85 <i>M<i/><sub>⊙<sub/>. By investigating the main characteristics of the <i>υ<i/> sin <i>i<i/> distribution of O stars and BSGs as a function of <i>T<i/><sub>eff<sub/>, we propose that an efficient mechanism transporting angular momentum from the stellar core to the surface might be operating along the main sequence in the high-mass domain. We find correlations between <i>ξ<i/>,<i>υ<i/><sub>mac<sub/> and the spectroscopic luminosity <i>𝓛<i/> (defined as <i>T<i/><sub>eff<sub/><sup>4<sup/> / <i>g<i/>). We also find that no more than 20% of the stars in our sample have atmospheres clearly enriched in helium, and suggest that the origin of this specific subsample might be in binary evolution. We do not find clear empirical evidence of an increase in the wind strength over the wind bi-stability region toward lower <i>T<i/><sub>eff<sub/>.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141725805","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}

{"title":"The aspherical explosions of the 03fg-like Type Ia supernovae 2021zny and 2022ilv revealed by polarimetry","authors":"T. Nagao, K. Maeda, S. Mattila, H. Kuncarayakti, C. P. Gutiérrez, A. Cikota","doi":"10.1051/0004-6361/202449999","DOIUrl":"https://doi.org/10.1051/0004-6361/202449999","url":null,"abstract":"<i>Context.<i/> A peculiar subtype of Type Ia supernovae (SNe), 03fg-like (super-Chandrasekhar) SNe, show different observational properties from prototypical Type Ia SNe: they typically have high luminosities at the light-curve peak, low expansion velocities, and strong carbon features. The origin of this class of Type Ia SNe has been actively debated. Recent nebular-phase infrared observations of the 03fg-like Type Ia SN 2022pul using the <i>James Webb<i/> Space Telescope revealed large-scale asymmetries in the ejecta and the presence of the strong [Ne II] line at 12.81 μm, suggesting a violent merger of two white dwarfs as its origin.<i>Aims.<i/> Polarimetry is another powerful tool for studying the overall ejecta asymmetries of spatially unresolved SNe. Here, we aim to check the universality of the violent merger scenario as the origin of 03fg-like Type Ia SNe, by studying their explosion geometries using polarimetry.<i>Methods.<i/> In this Letter we present imaging-polarimetric observations of the two 03fg-like Type Ia SNe 2021zny and 2022ilv.<i>Results.<i/> SNe 2021zny and 2022ilv show high intrinsic polarization (∼1%–∼2%), which might be composed of multiple components with different polarization angles. This indicates that they have complex aspherical structures in their ejecta, supporting the violent merger scenario for their origin. Our observations provide the first clear evidence from polarimetry for such aspherical structures.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141725804","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}

{"title":"Planet-driven spirals in protoplanetary discs: Limitations of the semi-analytical theory for observations","authors":"D. Fasano, A. J. Winter, M. Benisty, G. Rosotti, A. Ruzza, G. Lodato, C. Toci, T. Hilder, A. Izquierdo, D. Price","doi":"10.1051/0004-6361/202450087","DOIUrl":"https://doi.org/10.1051/0004-6361/202450087","url":null,"abstract":"<i>Context.<i/> Detecting protoplanets during their formation stage is an important but elusive goal of modern astronomy. Kinematic detections via the spiral wakes in the gaseous disc are a promising avenue to achieve this goal.<i>Aims.<i/> We aim to test the applicability of a commonly used semi-analytical model for planet-induced spiral waves to observations in the low and intermediate planet mass regimes. In contrast to previous works that proposed using the semi-analytical model to interpret observations, in this study we analyse for the first time both the structure of the velocity and density perturbations. <i>Methods.<i/> We ran a set of FARGO3D hydrodynamic simulations and compared them with the output of the semi-analytic model in the code WAKEFLOW. We divided the disc into two regions. We used the density and velocity fields from the simulation in the linear region, where density waves are excited. In the non-linear region, where density waves propagate through the disc, we then solved Burgers’ equation to obtain the density field, from which we computed the velocity field.<i>Results.<i/> We find that the velocity field derived from the analytic theory is discontinuous at the interface between the linear and nonlinear regions. After ~0.2 <i>r<i/><sub>p<sub/> from the planet, the behaviour of the velocity field closely follows that of the density perturbations. In the low mass limit, the analytical model is in qualitative agreement with the simulations, although it underestimates the azimuthal width and the amplitude of the perturbations, predicting a stronger decay but a slower azimuthal advance of the shock fronts. In the intermediate regime, the discrepancy increases, resulting in a different pitch angle between the spirals of the simulations and the analytic model.<i>Conclusions.<i/> The implementation of a fitting procedure based on the minimisation of intensity residuals is bound to fail due to the deviation in pitch angle between the analytic model and the simulations. In order to apply this model to observations, it needs to be revisited so that it can also account for higher planet masses.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141631341","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}