The Astronomy and Astrophysics Review最新文献_第6页

Modelling the chemical evolution of the Milky Way 模拟银河系的化学演化过程

IF 27.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-08-27 DOI: 10.1007/s00159-021-00133-8

Francesca Matteucci

引用次数: 0

Geometry of radio pulsar signals: The origin of pulsation modes and nulling 射电脉冲星信号的几何结构:脉动模式的起源和消零

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-08-25 DOI: 10.1051/0004-6361/202141243

J. Dyks

引用次数: 0

Erratum: Temporal evolution of small-scale internetwork magnetic fields in the solar photosphere (A&A (2021) 647 (A182) DOI: 10.1051/0004-6361/202040028) 勘误:太阳光球中小尺度网络磁场的时间演变(A&A (2021) 647 (A182) DOI: 10.1051/0004-6361/202040028)

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-08-01 DOI: 10.1051/0004-6361/202040028E

R. J. Campbell, M. Mathioudakis, M. Collados, P. Keys, A. Ramos, C. Nelson, D. Kuridze, A. Reid

引用次数: 0

ORion Alma New GEneration Survey (ORANGES). I. Dust continuum and free-free emission of OMC-2/3 filament protostars 猎户座Alma新生代调查(橙)。1 . OMC-2/3丝原星的尘埃连续体和自由-自由发射

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-07-21 DOI: 10.1051/0004-6361/202141157

M. Bouvier, A. L'opez-Sepulcre, C. Ceccarelli, N. Sakai, S. Yamamoto, Y.-L. Yang

{"title":"ORion Alma New GEneration Survey (ORANGES). I. Dust continuum and free-free emission of OMC-2/3 filament protostars","authors":"M. Bouvier, A. L'opez-Sepulcre, C. Ceccarelli, N. Sakai, S. Yamamoto, Y.-L. Yang","doi":"10.1051/0004-6361/202141157","DOIUrl":"https://doi.org/10.1051/0004-6361/202141157","url":null,"abstract":"The spectral energy distribution (SED) in the millimetre (mm) to centimetre (cm) range is a useful tool for characterising the dust in protostellar envelopes as well as free-free emission from the protostar and outflow. While many studies have been carried out towards low- and high-mass protostars, little exists so far about solar-type protostars in high-mass star-forming regions, which are likely to be representatives of the conditions where the Solar System was born. We focus here on the OMC-2/3 solar-type protostars, which are bounded by nearby HII regions and which are, therefore, potentially affected by the high-UV illumination. We aim to understand whether the small-scale structure ($leq$1000 au) and the evolutionary status of these solar-type protostars are affected by the nearby HII regions, as is the case for the large-scale ($leq$10$^4$ au) gas chemical composition. We used ALMA in the 1.3 mm band (246.2 GHz) to image the continuum of 16 OMC-2/3 solar-type protostars, with an angular resolution of 0.25$''$ (100 au). We completed our data with archival data from the VANDAM survey of Orion Protostars at 333 and 32.9 GHz, respectively, to construct the dust SED, extract several dust parameters and to assess whether free-free emission is contaminating their dust SED in the cm range. From the mm to cm range dust SED, we found low dust emissivity spectral indexes ($beta < 1$) for the majority of our source sample and free-free emission towards only 5 of the 16 sample sources. We were also able to confirm or correct the evolutionary status of the source sample. Finally, we did not find any dependence of the source dust parameters on their location in the OMC-2/3 filament. Our results show that the small-scale dust properties of the OMC-2/3 protostars are not affected by the high- UV illumination from the nearby HII regions.","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"32 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2021-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76017475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 3

Modeling accretion shocks at the disk-envelope interface. Sulfur chemistry 模拟盘壳界面的吸积冲击。硫的化学

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-07-20 DOI: 10.1051/0004-6361/202141591

M. Gelder, B. Tabone, E. Dishoeck, B. Godard

{"title":"Modeling accretion shocks at the disk-envelope interface. Sulfur chemistry","authors":"M. Gelder, B. Tabone, E. Dishoeck, B. Godard","doi":"10.1051/0004-6361/202141591","DOIUrl":"https://doi.org/10.1051/0004-6361/202141591","url":null,"abstract":"As material from an infalling protostellar envelope hits the forming disk, an accretion shock may develop which could (partially) alter the envelope material entering the disk. Observations with the Atacama Large Millimeter/submillimeter Array (ALMA) indicate that emission originating from warm SO and SO$_2$ might be good tracers of such accretion shocks. The goal of this work is to test under what shock conditions the abundances of gas-phase SO and SO$_2$ increase in an accretion shock at the disk-envelope interface. Detailed shock models including gas dynamics are computed using the Paris-Durham shock code for non-magnetized J-type accretion shocks in typical inner envelope conditions. The effect of pre-shock density, shock velocity, and strength of the ultraviolet (UV) radiation field on the abundance of warm SO and SO$_2$ is explored. Warm gas-phase chemistry is efficient in forming SO under most J-type shock conditions considered. In lower-velocity (~3 km/s) shocks, the abundance of SO is increased through subsequent reactions starting from thermally desorbed CH$_4$ toward H$_2$CO and finally SO. In higher velocity (>4 km/s) shocks, both SO and SO$_2$ are formed through reactions of OH and atomic S. The strength of the UV radiation field is crucial for SO and in particular SO$_2$ formation through the photodissociation of H$_2$O. Thermal desorption of SO and SO$_2$ ice is only relevant in high-velocity (>5 km/s) shocks at high densities ($>10^7$ cm$^{-3}$). Warm emission from SO and SO$_2$ is a possible tracer of accretion shocks at the disk-envelope interface as long as a local UV field is present. Additional observations with ALMA at high-angular resolution could provide further constraints. Moreover, the James Webb Space Telescope will give access to other possible slow, dense shock tracers such as H$_2$, H$_2$O, and [S I] 25$mu$m.","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"99 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2021-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90845480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 9

Asteroseismology of evolved stars with EGGMiMoSA. I. Theoretical mixed-mode patterns from the subgiant to the RGB phase 演化恒星的星震学与EGGMiMoSA。1 .从亚巨星到RGB阶段的理论混合模式

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-07-16 DOI: 10.1051/0004-6361/202141317

M. Farnir, C. Pinçon, M. Dupret, A. Noels, R. Scuflaire

{"title":"Asteroseismology of evolved stars with EGGMiMoSA. I. Theoretical mixed-mode patterns from the subgiant to the RGB phase","authors":"M. Farnir, C. Pinçon, M. Dupret, A. Noels, R. Scuflaire","doi":"10.1051/0004-6361/202141317","DOIUrl":"https://doi.org/10.1051/0004-6361/202141317","url":null,"abstract":"This study is the first of a series of papers that provide a technique to analyse the mixed-modes frequency spectra and characterise the structure of stars on the subgiant and red-giant branches. We define seismic indicators, relevant of the stellar structure and study their evolution on a grid of models. The proposed method, EGGMiMoSA, relies on the asymptotic description of mixed modes, defines initial guesses for the parameters, and uses a Levenberg-Marquardt technique to adjust the mixed-modes pattern efficiently. We follow the evolution of the mixed-modes parameters along a grid of models from the subgiant phase to the RGB bump and extend past works. We show the impact of the mass and composition on their evolution. The evolution of the period spacing $Deltapi_1$, pressure offset $epsilon_p$, gravity offset $epsilon_g$, and coupling factor $q$ as a function of $Deltanu$ is little affected by the chemical composition and it follows two different regimes depending on the evolutionary stage. On the subgiant branch, the models display a moderate core-envelope density contrast. The evolution of $Delta pi_1$, $epsilon_p$, $epsilon_g$, and $q$ thus significantly changes with the mass. Also, we demonstrate that, at fixed Z/X and with proper measurements of $Deltapi_1$ and $Deltanu$, we may unambiguously constrain the mass, radius and age of a subgiant star. Conversely, on the red-giant branch, the core-envelope density contrast becomes very large. Consequently, the evolution of $epsilon_p$, $epsilon_g$ and $q$ as a function of $Deltanu$ becomes independent of the mass. This is also true for $Delta pi_1$ in stars with masses $lesssim 1.8M_odot$ because of core electron degeneracy. This degeneracy is lifted for higher masses, again allowing for a precise measurement of the age. Overall, our computations qualitatively agree with past observed and theoretical studies.","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"102 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2021-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80527269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 2

Induced differential rotation and mixing in asynchronous binary stars 异步双星的诱导微分旋转和混合

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-07-16 DOI: 10.1051/0004-6361/202039369

G. Koenigsberger, E. Moreno, N. Langer

{"title":"Induced differential rotation and mixing in asynchronous binary stars","authors":"G. Koenigsberger, E. Moreno, N. Langer","doi":"10.1051/0004-6361/202039369","DOIUrl":"https://doi.org/10.1051/0004-6361/202039369","url":null,"abstract":"Rotation contributes to internal mixing processes and observed variability in massive stars. A significant number of binary stars are not in strict synchronous rotation, including all eccentric systems. This leads to a tidally induced and time-variable differential rotation structure. We present a method for exploring the rotation structure of asynchronously rotating binaries. We solve the equations of motion of a 3D grid of volume elements located above the rigidly rotating core in the presence of gravitational, centrifugal, Coriolis, gas pressure and viscous forces to obtain the angular velocity as a function of the three spatial coordinates and time. We find that the induced rotation structure and its temporal variability depend on the degree of departure from synchronicity. In eccentric systems, the structure changes over the orbital cycle with maximum amplitudes occurring potentially at orbital phases other than periastron passage. We discuss the possible role of the time-dependent tidal flows in enhancing the mixing efficiency and speculate that, in this context, slowly rotating asynchronous binaries could have more efficient mixing than the analogous more rapidly rotating but tidally locked systems. We find that some observed nitrogen abundances depend on the orbital inclination, which, if real, would imply an inhomogeneous chemical distribution over the stellar surface or that tidally induced spectral line variability, which is strongest near the equator, affects the abundance determinations. Our models predict that, neglecting other angular momentum transfer mechanisms, a pronounced initial differential rotation structure converges toward average uniform rotation on the viscous timescale. We suggest that by taking into account the processes that are triggered by asynchronous rotation, a broader perspective of binary star structure, evolution and variability may be gleaned.","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"31 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2021-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73681475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

X-ray analysis of the Planck-detected triplet-cluster-system PLCK G334.8-38 planck探测到的三重星团系统PLCK G334.8-38的x射线分析

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-07-14 DOI: 10.1051/0004-6361/202140657

A. Kolodzig, N. Aghanim, M. Douspis, E. Pointecouteau, Edouard Lecoq

{"title":"X-ray analysis of the Planck-detected triplet-cluster-system PLCK G334.8-38","authors":"A. Kolodzig, N. Aghanim, M. Douspis, E. Pointecouteau, Edouard Lecoq","doi":"10.1051/0004-6361/202140657","DOIUrl":"https://doi.org/10.1051/0004-6361/202140657","url":null,"abstract":"We conducted an X-ray analysis of one of the two Planck-detected triplet-cluster systems, PLCK G334.8-38.0, with a $sim100$~ks deep XMM-Newton data. We find that the system has a redshift of $z=0.37pm{0.01}$ but the precision of the X-ray spectroscopy for two members is too low to rule out a projected triplet system, demanding optical spectroscopy for further investigation. In projection, the system looks almost like an equilateral triangle with an edge length of $sim2.0,mathrm{Mpc}$, but masses are very unevenly distributed ($M_{500} sim [2.5,0.7,0.3] times 10^{14},mathrm{M_{odot}}$ from bright to faint). The brightest member appears to be a relaxed cool-core cluster and is more than twice as massive as both other members combined. The second brightest member appears to be a disturbed non-cool-core cluster and the third member was too faint to make any classification. None of the clusters have an overlapping $R_{500}$ region and no signs of cluster interaction were found; however, the XMM-Newton data alone are probably not sensitive enough to detect such signs, and a joint analysis of X-ray and the thermal Sunyaev-Zeldovich effect (tSZ) is needed for further investigation, which may also reveal the presence of the warm-hot intergalactic medium (WHIM) within the system. The comparison with the other Planck-detected triplet-cluster-system (PLCK G214.6+36.9) shows that they have rather different configurations, suggesting rather different merger scenarios, under the assumption that they are both not simply projected triplet systems.","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"84 5 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2021-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89329448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

TOI-1296b and TOI-1298b observed with TESS and SOPHIE: Two hot Saturn-mass exoplanets with different densities around metal-rich stars TESS和SOPHIE观测到的TOI-1296b和TOI-1298b:两颗热的土星质量的系外行星，它们围绕着富含金属的恒星，密度不同

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-07-14 DOI: 10.1051/0004-6361/202141151

C. Moutou, J. Almenara, G. H'ebrard, N. Santos, K. Stassun, S. Deheuvels, S. Barros, P. Benni, A. Bieryla, I. Boisse, X. Bonfils, P. Boyd, K. Collins, D. Baker, P. Cort'es-Zuleta, S. Dalal, F. Debras, M. Deleuil, X. Delfosse, O. Demangeon, Z. Essack, T. Forveille, E. Girardin, P. Guerra, N. Heidari, K. Hesse, S. Hoyer, J. Jenkins, F. Kiefer, P. Konig, D. Laloum, D. Latham, T. Lopez, E. Martioli, H. Osborn, G. Ricker, S. Seager, R. Vanderspek, M. Vezie, J. Villaseñor, J. Winn, B. Wohler, C. Ziegler

{"title":"TOI-1296b and TOI-1298b observed with TESS and SOPHIE: Two hot Saturn-mass exoplanets with different densities around metal-rich stars","authors":"C. Moutou, J. Almenara, G. H'ebrard, N. Santos, K. Stassun, S. Deheuvels, S. Barros, P. Benni, A. Bieryla, I. Boisse, X. Bonfils, P. Boyd, K. Collins, D. Baker, P. Cort'es-Zuleta, S. Dalal, F. Debras, M. Deleuil, X. Delfosse, O. Demangeon, Z. Essack, T. Forveille, E. Girardin, P. Guerra, N. Heidari, K. Hesse, S. Hoyer, J. Jenkins, F. Kiefer, P. Konig, D. Laloum, D. Latham, T. Lopez, E. Martioli, H. Osborn, G. Ricker, S. Seager, R. Vanderspek, M. Vezie, J. Villaseñor, J. Winn, B. Wohler, C. Ziegler","doi":"10.1051/0004-6361/202141151","DOIUrl":"https://doi.org/10.1051/0004-6361/202141151","url":null,"abstract":"We present the discovery of two new transiting extrasolar planet candidates identified as TOI-1296.01 and TOI-1298.01 by the Transiting Exoplanet Survey Satellite (TESS). The planetary nature of these candidates has been secured with the SOPHIE high-precision spectrograph through the measurement of the companion’s mass with the radial velocity method. Both planets are similar to Saturn in mass and have similar orbital periods of a few days. They, however, show discrepant radii and therefore different densities. The radius discrepancy might be explained by the different levels of irradiation by the host stars. The subgiant star TOI-1296 hosts a low-density planet with 1.2 RJup while the less luminous, lower-size star TOI-1298 hosts a much denser planet with a 0.84 RJup radius, resulting in bulk densities of 0.198 and 0.743 g.cm−3, respectively. In addition, both stars are strongly enriched in heavy elements, having metallicities of +0.44 and +0.49 dex, respectively. The planet masses and orbital periods are 0.298± 0.039 MJup and 3.9443715± 5.8 10−6 days for TOI-1296b, and 0.356± 0.032 MJup and 4.537164± 1.2 10−5 days for TOI-1298b. The mass measurements have a relative precision of better than 13%.","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"3 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2021-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86626840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 4

Strong dependence of the physical properties of cores on spatial resolution in observations and simulations 在观测和模拟中，岩心的物理性质对空间分辨率有很强的依赖性

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-07-13 DOI: 10.1051/0004-6361/202040053

F. Louvet, P. Hennebelle, A. Men’shchikov, P. Didelon, E. Ntormousi, F. Motte

{"title":"Strong dependence of the physical properties of cores on spatial resolution in observations and simulations","authors":"F. Louvet, P. Hennebelle, A. Men’shchikov, P. Didelon, E. Ntormousi, F. Motte","doi":"10.1051/0004-6361/202040053","DOIUrl":"https://doi.org/10.1051/0004-6361/202040053","url":null,"abstract":"During the last decade in star formation research, many studies have targeted low- and high-mass star formation regions located at different distances, with different telescopes having specific angular resolution capabilities. We present a systematic investigation of the angular resolution effects, with special attention being paid to the derived masses of sources as well as the shape of the resulting source mass functions (SMFs). We tested the impact of angular resolution, from 0.6 down to 0.02 pc, in two star-forming regions observed with Herschel (NGC6334 and Aquila), and three (magneto)-hydrodynamical simulations. We detected and measured sources at each resolution using getsf and we analysed the derived masses and sizes of the sources. We find that the number of sources does not converge from 0.6 to 0.05 pc. It increases by about two when the angular resolution increases with a similar factor. Below 0.05 pc, the number of source still increases by about 1.3 when the angular resolution increases by two, suggesting that we are close to, but not yet at, convergence. We find that the measured sizes and masses of sources linearly depend on the angular resolution with no sign of convergence to a resolution-independent value. The corresponding SMF peak also shifts with angular resolution, while the slope of the high-mass tail of the SMFs remains almost invariant. If prestellar cores, physically distinct from their background, exist in cluster-forming molecular clouds, we conclude that their mass must be lower than reported so far in the literature. We discuss various implications for the studies of star formation: the problem of determining the mass reservoirs involved in the star-formation process; the inapplicability of the Gaussian beam deconvolution to infer source sizes; and the impossibility to determine the efficiency of the mass conversion from the cores to the stars.","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"1 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90841997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 3