We present a new statistical algorithm of Chemical Evolution implemented into the Tree-SPH code developed by Lia & Carraro (2000 MNRAS 314, 145)

Carraro, G

Lia, C

Portinari, L

arXiv

We present a new statistical algorithm of Chemical Evolution implemented into the Tree-SPH code developed by Lia & Carraro (2000)

CARRARO, GIOVANNI

Portinari,L

Lia,C

Archivio istituzionale della ricerca - Università di Padova

Original Citation:Coupling Chemical Evolution with SPHPublisher:Published version:DOI:Terms of use:Open Access(Article begins on next page)This article is made available under terms and conditions applicable to Open Access Guidelines, asdescribed at http://www.unipd.it/download/file/fid/55401 (Italian only)Availability:This version is available at: 11577/3212497 since: 2016-11-23T19:50:50ZUniversità degli Studi di PadovaPadua Research Archive - Institutional RepositoryarXiv:astro-ph/0110019v1  1 Oct 2001THE PHYSICS OF GALAXY FORMATIONASP Conference Series, Vol. ***, 2001M. Umemura, and H. Susa, eds.Coupling Chemical Evolution with SPHGiovanni CarraroAstronomy Department, Padova University, Vicolo Osservatorio 2,I-35122, PadovaLaura PortinariTheoretical Astrophysics Center, Juliane Marie Vej 30, DK-2100,CopenhagenCesario LiaSISSA/ISAS, Via Beirut 2, I-34014, TriesteAbstract. We present a new statistical algorithm of Chemical Evolu-tion implemented into the Tree-SPH code developed by Lia & Carraro(2000).In Smoothed Particles Hydrodynamics (SPH) codes with a large number of par-ticles, star formation as well as gas and metal restitution from dying stars can betreated statistically. This approach allows to include detailed chemical evolutionand gas re-ejection with minor computational effort. Here we draw the attentionon a new statistical algorithm for star formation (SF) and chemical evolution,especially conceived for SPH simulations with large numbers of particles, andfor parallel SPH codes described in full detail elsewhere in Lia et al (2001).Basically SF is treated with a probabilistic approach, and when stars are formedthey are considered as a single stellar population (SSP) for which gas restitutionand metal production for different species (He, Fe, Ca, Z, Mg, O, N, C, S andtotal metallicity Z) are computed as a function of the age of the SSP, taking intoaccount the role of single stars of all masses and lifetimes, as well as of TypeIa SN. Our simulations include also Feed-Back from SNæ of both type Ia andII, and stellar winds. A diffusion mechanism is adopted to spread metals in theinterstellar medium (ISM). A novelty of our approach is that also the gas andmetals restitution is treated in a probabilistic manner.We present two astrophysical simulations obtained with this algorithm.In the first one, we follow the formation of an individual disc–like galaxy, predictthe final structure, the metallicity evolution and metallicity gradients. In theleft panel of Fig. 1 we present the trend of [O/Fe] vs. [Fe/H] at the end of thesimulation, and compare it with observational data for the solar vicinity.In the second one we simulate the formation and evolution of a cluster of galax-ies, to demonstrate the capabilities of the algorithm in investigating the chemo-dynamical evolution of the intergalactic medium in a cosmological context. Theright panel of Fig. 1 shows the enrichment of the intra-cluster medium in global12 Carraro, Portinari and LiaFigure 1. Chemical enrichemnt of a disk galaxy model (left panel)and of the intra-cluster medium (right panle).metallicity (Z), [Fe/H] and [O/Fe]. Whenever it is possible, a comparison is madewith observational data for cluster of galaxies. As one can note, the agreementis very good.Our implementation is intended to be easily implemented into any SPH code.Anybody interested is welcome.Acknowledgments. GC deeply thanks IAU for financial support. Theauthors acknowledge useful discussions with Jesper Sommer-Larsen and ClaudioDalla Vecchia.ReferencesArnaud M., Evrard A.E., 1999, MNRAS 305, 631Carretta E., Gratton R.G., Sneden C., 2000, A&A 356, 238Ishimaru Y., Arimoto N., 1997, PASJ 49, 1Kroupa P., 1998, MNRAS 298, 231Lia C., Carraro G., 2000, MNRAS 314, 145Lia C., Portinari L., Carraro G., 2001, MNRAS, submittedMatsumoto H. et al, 2000, PASJ 52, 153

Coupling Chemical Evolution with SPH

Abstract

Similar works

Full text

Available Versions

Archivio istituzionale della ricerca - Università di Padova