Filamentary void haloes in CosmoGrid Steven Rieder, Rien van de Weygaert, Marius Cautun, Burcu Beygu, Simon Portegies Zwart DOI: 10.1093/mnras/stt1288 @rieder CosmoGrid • ΛCDM simulation • 20483 particles (also 10243, 5123) • (30 Mpc)3 volume • 105 M⊙ per particle • 175 pc softening • ~500 snapshots over a Hubble time (z = 65 – 0) Oort building, 4th floor (1 above Lorentz) CosmoGrid Millennium • very high mass & spatial resolution Millennium II • limited large scale coverage • very useful for case studies (not for precise statistical purposes) CosmoGrid CosmoG rid raw data an d halo c availabl atalogu e on req e uest! CosmoGrid Millennium • very high mass & spatial resolution Millennium II • limited large scale coverage • very useful for case studies (not for precise statistical purposes) CosmoGrid CosmoG rid raw data an d halo c availabl atalogu e on req e uest! CosmoGrid network with Derek Groen, Tomoaki Ishiyama CosmoGrid network with Derek Groen, Tomoaki Ishiyama CosmoGrid network with Derek Groen, Tomoaki Ishiyama CosmoGrid network with Derek Groen, Tomoaki Ishiyama CosmoGrid network with Derek Groen, Tomoaki Ishiyama CosmoGrid network with Derek Groen, Tomoaki Ishiyama Setup • Transfer boundary particles • • to neighbour computer MPI for interprocess communication on each site MPWide (Groen etal 2011) for communication between sites t [s] 150 100 CosmoGrid efficiency 50 250 25 200 • Total overhead with 2048 20 t [s] t [s] processes and 3 sites: 10% ! Calculation time Communication time TotalParticle time using 1 site migration Determine boundary PP PM • Overhead decreases for larger number of particles 150 15 100 10 50 5 0 25 20 t [s] 15 10 20 40 60 80 100 120 140 160 Simulation step number Particle migration Determine boundary PP PM 180 Void galaxy environment • VGS31: a system of 3 galaxies in a void (Beygu etal 13) ! • When did this system form? • What is its environment like? Void galaxy environment • VGS31: a system of 3 galaxies in a void (Beygu etal 13) ! • When did this system form? • What is its environment like? Systems like VGS31 • 8 systems similar to VGS31 in CosmoGrid • Selection based on: • void environment • halo mass • system size VGS31 0 CGVG CGVD Formation history time [Gyr] 1011 Mvir [Msun] 1010 109 108 CGVD CGVG 0 2 4 6 8 10 12 14 t [Gyr] 13.5 Colour scheme (python, gnuplot, matplotlib): http://www.sron.nl/~pault/ 0 CGVG CGVD Formation history time [Gyr] 1011 Mvir [Msun] 1010 109 108 CGVD CGVG 0 2 4 6 8 10 12 14 t [Gyr] 13.5 Colour scheme (python, gnuplot, matplotlib): http://www.sron.nl/~pault/ 0 CGVG CGVD Formation history time [Gyr] 1011 Mvir [Msun] 1010 109 108 CGVD CGVG 0 2 4 6 8 10 12 14 t [Gyr] 13.5 Colour scheme (python, gnuplot, matplotlib): http://www.sron.nl/~pault/ System evolution physical distance [kpc] 350 CGVA CGVB 300 CGVC CGVD CGVE 250 CGVF CGVG CGVH 200 150 100 50 0 0 2 4 6 8 time [Gyr] 10 12 14 1 0 X [h-1 Mpc] X CGVG Y Z -1 1 0 X [h-1 Mpc] X CGVG Y Z -1 Environment CGVG Y 1 h-1 Mpc X 1 h-1 Mpc Environment 7 h-1 Mpc Y 1 h-1 Mpc X Y 7 h-1 Mpc CGVG X 1 h-1 Mpc Environment 7 h-1 Mpc Y 1 h-1 Mpc 7 h-1 Mpc 7 h-1 Mpc CGVG Z X X Y 7 h-1 Mpc X 1 h-1 Mpc Environment 7 h-1 Mpc Y 1 h-1 Mpc 7 h-1 Mpc Z 7 h-1 Mpc 7 h-1 Mpc 7 h-1 Mpc CGVG Z X X Y X Y 1 h-1 Mpc 7 h-1 Mpc CGVG Y 7 h-1 Mpc CGVG Y 7 h-1 Mpc CGVG Environmental evolution 0 ! • to investigate environment Blue: filaments, Orange: walls time [Gyr] • Use Nexus+ (Cautun etal 13) ! • All void halo groups form in tenuous wall, most also in a thin filament 5 h-1 Mpc 13.5 Velocity fields CGVA CGVD Take home messages • CosmoGrid: high resolution ΛCDM, data available • Void halo systems have diverse formation histories, but were always close together • Void halo systems reside in tenuous intra-void walls and filaments
© Copyright 2025 ExpyDoc
