1. NUMERICAL ASTROPHYSICS - General aspects - INAF-Cineca agreement - Bologna Workshop (2002)

2. NUMERICAL ASTROPHYSICS Involved people: Annibale D’Ercole (INAF-OAB, Associated Astron.) Reasearch area: Gas flows in interstellar medium: models and hydrodynamical numerical simulations Main collaborations F. Brighenti, A. Marcolini (Bologna University) F. Matteucci (Trieste University) S. Recchi (Kiel University) T. Heckman, D. Strickland (Johns Hopkins University Baltimore )

3. Recent field of interest: Chemical and Dynamical Evolution of Starburst Galaxies. Are the SNII metals ejected by the galactic wind? Can the ram pressure stripping influence the metal ejection? Can evaporation of clouds explain X-ray, UV and H  observations in starburst galaxies? Tools: 3D parallel hydrocode, CINECA supercomputers, Chandra & FUSE observations. Financial support: Cofin INAF 2002 Cofin MURST 2003 national P.I.: J. Danziger (OAT) F. Matteucci (Trieste Univ.) local P.I.: A. D’Ercole A. D’Ercole duration: 2 yr 2 yr budget: € 8,000 € 22,000

4. black= no ram pressure, blu=edge-on models, green=45° model, yellow= face-on model n 0 =10 -4 cm -3, T 0 =10 6 K, v 0 =200 km s -1

7. Recent publications A. Marcolini, F. Brighenti, A. D’Ercole, Three-dimensional simulations of the interstellar medium in dwarf galaxies – I. Ram pressure stripping. 2003, MNRAS, 345, 1329 A. Marcolini, F. Brighenti, A. D’Ercole, Three-dimensional simulations of the interstellar medium in dwarf galaxies – II. Galactic winds. MNRAS, submitted A. Marcolini, D. Strickland, A. D’Ercole, T. Heckman, Dynamical and radiative properties of conductive clouds embedded in galactic winds. MNRAS, in preparation

8. Projects Galactic winds in more realistic (non isothermal) models of dwarf galaxies Study of winds from bulges of spiral galaxies and their impact on the chemical evolution of the disks (D’Ercole, Brighenti + students) Interaction of globular clusters with the Galactic halo: the ram pressure effect [Marcolini, D’Ercole, Wyse (Johns Hopkins), Brighenti]

9. Involved people: Roberto Bedogni (Researcher Astron.) Reasearch area: Evolution of young type I SN and the role of turbulence in protostellar and protogalactic formation Main collaborations A.Di Fazio, (Roma Astron. Obs.) R. Bedogni, A. Di Fazio The evolution of self-gravitating protocloud with variable cloud drag and turbulence In preparation Di Fazio and Y.I. Izotov Galaxy formation and protogalactic evolution down to the formation of Population 0 stars Submitted to Astronomy and Astrophysics Numerical Astrophysics

10. Young SN remnants evolution Evolution of a TypeI SN Remnants: A SN shock given by a Self Similar Solution is starting at an initial time=100 yr and interacts with a cloud 100 times denser than the ambient medium. The ambient medium has a 10000 O K temperature and a 1 particle/cm -3 density The frame shows the remnants evolution after ~1200 yr

11. NUMERICAL ASTROPHYSICS Involved people Pasquale Londrillo (Researcher Astron.) Reasearch area: Numerical modeling and investigation of N-body gravitating systems and of MHD (magneto-hydrodynamical) flows in astrophysical conditions Main collaborations L. Ciotti, (Bologna Astron. Depart.) C. Nipoti, (Bologna Astron. Depart.) L. Del Zanna, (Firenze Astron. Depart.) M. Velli, (Firenze University) R. Grappin, (Paris, Observatoire de Meudon) Financial Support Cofin MURST 2000-2002 and 2002-2004 Project on : Plasma astrophysics and turbulence national P.I.: M. Velli (Phys. Depart. Firenze) budget: 69.000

12. A new N-body code (FVfps) for investigating the galaxy structure stability and merging processes has been implemented and parallelized using MPI. The code takes advantage of new designed fast algorithms (Dehnen, JCP 2002) as Poisson solver based on multipole method Performaces: (Mem SAiT n.1 2003) Activity on Numerical N-body systems

13. Application of the code to the study of the dynamical effects of merging process on the fundamental plane properties of the elliptical galaxies in: C. Nipoti, P. Londrillo and L. Ciotti, MNRAS, 332(4), (2002) C. Nipoti, P. Londrillo and L. Ciotti MNRAS, 342(2),(2003)

14. Activity on Numerical MHD New algorithms for upwind schemes have been developped to integrate at high accuracy orders the MHD system in 3D as required by typical astrophysical regimes ( solar wind, interstellar space, high speed flows and turbulence). The main computational results refer to the flux conservation properties of the magnetic field in presence of discontinuities. P. Londrillo and L. Del Zanna (J. Comput.Phys., 2003)

15. Extension to the (special) relativistic regime, in: L. DelZanna, N. Bucciantini and P. Londrillo, Astron.Astrophys., 400 (2003) Applications: L.Del Zanna, M. Velli and P. Londrillo: Parametric decay of circularly polarized Alfven waves: multidimensional simulations in periodic and open domains Astron.Astrophys. 367 (2001)

16. -To construct adaptive gas-dynamics (and MHD) Eulerian schemes (grids) for gravitating systems, to be coupled to collisionless components described in the N-body code. Collaborations: V. Antonuccio de Logu and U. Becciani (INAF, Catania) C. Gheller (CINECA, Bologna) -To investigate structure and stability properties of exact equilibrium distribution functions, representing tori-shaped systems of collisionless components (stars). Collaborations: L. Ciotti (Bologna, Astr.Dep.) and G. Bertin (Milano, University) -To investigate MHD turbulence at high spatial resolution, to study heating and accelaration processes in hot intergalactic space. Collaborations: G. Brunetti (IRA, Bologna) Projects and work in progress