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dc.contributor.authorMendigutía, I.
dc.contributor.authorMora, Alcione
dc.contributor.authorMontesinos, Benjamín
dc.contributor.authorEiroa, Carlos
dc.contributor.authorMeeus, Gwendolyn 
dc.contributor.authorMerín, Bruno
dc.contributor.authorOudmaijer, René D.
dc.contributor.otherUAM. Departamento de Física Teóricaes_ES
dc.date.accessioned2014-09-19T12:14:07Z
dc.date.available2014-09-19T12:14:07Z
dc.date.issued2012-07-02
dc.identifier.citationAstronomy and Astrophysics 543 (2012): A59es_ES
dc.identifier.issn0004-6361 (print)es_ES
dc.identifier.issn1432-0746 (online)es_ES
dc.identifier.urihttp://hdl.handle.net/10486/661880
dc.descriptionAstronomy and Astrophysics 543 (2012): A59 Reproduced with permission from Astronomy & Astrophysicsen_US
dc.description.abstractContext. The mass accretion rate (Ṁacc) is a key parameter that has not accurately been determined for a wide sample of Herbig Ae/Be (HAeBe) stars until recently. Aims. We look for trends relating Ṁacc and the stellar ages (t), spectral energy distributions (SEDs), and disk masses for a sample of 38 HAeBe stars, comparing them to analogous correlations found for classical T Tauri stars. Our goal is ultimately to shed light on the timescale and physical processes that drive the evolution of intermediate-mass pre-main sequence objects. Methods. Mass accretion rates obtained by us in a previous work were related to several stellar and disk parameters: the age of the stars was compiled from the literature, SEDs were classified according to their shape and the wavelength where the IR excess starts, near- and mid-IR colour excesses were computed, and disk masses were estimated from mm fluxes. Results. ˙Macc decreases with the stellar age, showing a dissipation timescale τ = 1.3+1.0 −0.5 Myr from an exponential law fit, while a power law yields ˙Macc(t) ∝ t−η, with η = 1.8+1.4 −0.7. This result is based on our whole HAeBe sample (1–6 Mʘ), but the accretion rate decline most probably depends on smaller stellar mass bins. The near-IR excess is higher and starts at shorter wavelengths (J and H bands) for the strongest accretors. Active and passive disks are roughly divided by ∼2× 10−7 Mʘ yr−1. The mid-IR excess and the SED shape from the Meeus et al. classification are not correlated with Ṁacc. Concerning disk masses, we find Ṁacc ∝ M1.1±0.3 disk. Most stars in our sample with signs of inner dust dissipation typically show accretion rates ten times lower and disk masses three times smaller than the remaining objects. Conclusions. The trends relating Ṁacc with the near-IR excess and Mdisk extend those found for T Tauri stars, and are consistent with viscous disk models. The differences in the inner gas dissipation timescale, and the relative position of the stars with signs of inner dust clearing in the Vacc − Mdisk plane, could be suggesting a slightly faster evolution, and that a different process – such as photoevaporation – plays a more relevant role in dissipating disks in the HAeBe regime compared to T Tauri stars. Our conclusions must consider the mismatch between the disk mass estimates from mm fluxes and the disk mass estimates from accretion, which we also find in HAeBe starsen_US
dc.description.sponsorshipThis work is partially supported by grant AYA-2008 01727en_US
dc.format.extent21 pag.es_ES
dc.format.mimetypeapplication/pdfes_ES
dc.language.isoenges_ES
dc.publisherESOes_ES
dc.relation.ispartofAstronomy and Astrophysicsen_US
dc.rights© 2012 ESOes_ES
dc.subject.otherAccretion, accretion disksen_US
dc.subject.otherCircumstellar matteren_US
dc.subject.otherProtoplanetary disksen_US
dc.subject.otherStars: pre-main sequenceen_US
dc.subject.otherStars: variables: T Tauri, Herbig Ae/Been_US
dc.titleAccretion-related properties of Herbig Ae/Be stars: Comparison with T Taurisen_US
dc.typearticleen
dc.subject.ecienciaFísicaes_ES
dc.relation.publisherversionhttp://dx.doi.org/10.1051/0004-6361/201219110en_US
dc.identifier.doi10.1051/0004-6361/201219110es_ES
dc.identifier.publicationfirstpageA59es_ES
dc.identifier.publicationlastpageA59es_ES
dc.identifier.publicationvolume543es_ES
dc.type.versioninfo:eu-repo/semantics/publishedVersiones_ES
dc.rights.accessRightsopenAccessen
dc.authorUAMEiroa De San Francisco, Carlos (259722)
dc.authorUAMMeeus , Gwendolyn (264398)
dc.authorUAMMontesinos Comino , Benjamín (269116)
dc.facultadUAMFacultad de Ciencias


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