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Are All Satellite Galaxies Tdgs ? THAT IS Are There No Dark-Matter Satellites ?

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Are All Satellite Galaxies Tdgs ? THAT IS Are There No Dark-Matter Satellites ? Are all satellite galaxies TDGs ? THAT IS Are there no dark-matter satellites ? Satellites and Streams ESO, Santiago, Chile April, 13th-17th, 2015 based on Kroupa, 2012, http://adsabs.harvard.edu/abs/2012PASA...29..395K and Kroupa 2014, http://adsabs.harvard.edu/abs/2014arXiv1409.6302K and Kroupa 2015, http://adsabs.harvard.edu/abs/2015CaJPh..93..169K Pavel Kroupa Helmholtz-Institut fuer Strahlen und Kernphysik (HISKP) Helmholtz Institute for Radiation and Nuclear Physics c/o Argelander-Institut für Astronomie University of Bonn 1 Pavel Kroupa: University of Bonn Assume the standard model of cosmology (SMoC) is a valid description of the universe. this is synonymous to extrapolating the law of gravitation, derived empirically only on scales of the Solar System, by many orders of magnitude. 2 Pavel Kroupa: University of Bonn Formation of primoridal / DM dominated dwarf galaxies (PDGs) 3 Pavel Kroupa: University of Bonn Structures form according to the cosmological merger tree the beginning Big Bang Lacey & Cole (1993) DM sub- structures form first and coalesce to larger structures today 4 Pavel Kroupa: University of Bonn 250 kpc ≈ Pavel Kroupa: University of Bonn (Diemand et al. 2008) 5 Astrophysics of Galaxies VIII: LG . a fabulously huge industry of scientists (worth millions of Euros annually) work on trying to understand why the observed dwarfs DO NOT look like the theoretical ones (e.g. cusp/core problem; missing dwarf galaxy problem; "inner mass deficit" . ). Oman, Navarro, ... Frenk, Sawala, White, ... Shaye et al. : http://arxiv.org/abs/1504.01437 6 Pavel Kroupa: University of Bonn Formation of tidal dwarf galaxies (TDGs) 7 Pavel Kroupa: University of Bonn Structures form according to the cosmological merger tree the beginning Lacey & Cole (1993) galaxies interact and merge TDGs = tidal dwarf galaxies form today 8 Pavel Kroupa: University of Bonn Tidal tails Miho & Maxwell, web 9 Pavel Kroupa: University of Bonn (Weilbacher et al. 2000) NTDG ≈ 14 bulge Phase-space correlated formation satellites form in the same event TDG formation 10 Pavel Kroupa: University of Bonn 11 Pavel Kroupa: University of Bonn Relevance redshift Wetzstein, Naab & Burkert 2007 12 Pavel Kroupa: University of Bonn Intermediate- term evolution of TDGs The Time 13 Pavel Kroupa: University of Bonn TDG formation and evolution over first 3 Gyr Self-consistent high-resolution simulations of self-regulated TDGs show these to not disrupt Recchi et al. 2007; Ploeckinger et al. 2014, 2015 Ploeckinger et al. 2015 Mass--metallicity relation Recchi et al. 2015 (in press, yesterday on arXiv) 14 Pavel Kroupa: University of Bonn Observational evidence : . with 4 Gyr the oldest TDGs identified until now 15 Pavel Kroupa: University of Bonn Long-term evolution of TDGs The Time 16 Pavel Kroupa: University of Bonn Evolve dwarf galaxies w/o dark matter in a computer 17 Pavel Kroupa: University of Bonn 18 Pavel Kroupa: University of Bonn Star-cluster complex (cf Tadpole) 50 clusters 6 each 10 M⊙ clusters as fundamental galactic building blocks ⇓ Spheroidal dwarf galaxy ! (Fellhauer et al. 2001, 2002a,b,c, 2005; Pavel Kroupa: University of Bonn Kroupa: University Pavel Bekki et al. 2004) 19 1-10% of population in of Bonn Kroupa: University Pavel remnant 20 (Kroupa 1997) e =0.74 Remnants have a highly anisotropic f ( R ,V ) 5 and mass ≈ 10 M⊙ e =0.60 Pavel Kroupa: University of Bonn Kroupa: University Pavel 21 (Kroupa 1997) e =0.74 Remnants have a highly anisotropic f ( R ,V ) 5 and mass ≈ 10 M⊙ R ≈ few 100 pc M 2−3 and ≈ 10 ! L e =0.60 Pavel Kroupa: University of Bonn Kroupa: University Pavel 22 No evidence that TDGs dissolve, and predictions become successful ! 23 Pavel Kroupa: University of Bonn Hercules D=130kpc (Coleman et al. 2007) 24 Pavel Kroupa: University of Bonn Hercules D=130kpc (Coleman et al. 2007) 25 Pavel Kroupa: University of Bonn MV = −9 mag (Kroupa 1997) r0.5 =180pc very similar to Hercules ! M { =102.3 L 26 Pavel Kroupa: University of Bonn This is a real prediction 10 years before the discovery of this type of celestial object ! (see also Fellhauer et al.) 27 Pavel Kroupa: University of Bonn For the young scientists: It is not so clear whether the SMoC ever predicted anything of success ! 28 Pavel Kroupa: University of Bonn M/L vs luminosity Metz & Kroupa 2007 [solar units] " L M ! 10 log MV [mag] 29 Pavel Kroupa: AIfA, University of Bonn M/L vs luminosity [solar units] " L M ! 10 log globular clusters normal stellar population / no dark matter MV [mag] 30 Pavel Kroupa: AIfA, University of Bonn M/L vs luminosity Metz & Kroupa 2007 [solar units] " L M ! 10 log MV [mag] 31 Pavel Kroupa: AIfA, University of Bonn M/L vs luminosity Metz & Kroupa 2007 [solar units] " L M ! 10 log MV [mag] 32 Pavel Kroupa: AIfA, University of Bonn . once we leave the framework of dark matter, things brighten up : one obtains full predictability And, there is no existing evidence that TDGs dissolve 33 Pavel Kroupa: University of Bonn How many TDGs are expected in the SMoC? 34 Pavel Kroupa: University of Bonn Okazaki & Taniguchi (2000) : The galaxy interaction scheme proposed by Silk & Norman (1981) (Lacey & Cole 1993) 35 Pavel Kroupa: AIfA, University of Bonn Okazaki & Taniguchi (2000, ApJ) “Dwarf galaxy formation induced by galaxy interactions” 36 Pavel Kroupa: AIfA, University of Bonn Okazaki & Taniguchi (2000) : The galaxy interaction scheme proposed by Silk & Norman (1981) “can be responsible for the observed numbers of dEs in the various environs from poor groups of galaxies to the usual rich clusters of galaxies. The formation rate of long-lived TDGs is estimated to be 1–2 in each galaxy interaction." i.e. standard cosmology inherently means all dE’s to be TDGs But note, N TDG scales with gas content and thus evolutionary status / cosmological epoch of interacting galaxies (many more formed in the past). 37 Pavel Kroupa: AIfA, University of Bonn Pressure / random-motion supported stellar systems Dabringhausen et al. 2012 only one 4 10 type of dwarf galaxy exists ! 103 102 101 projected half-light radius [ pc ] GCs / UCDs elliptical galaxies 100 fit to giant ellipticals fit to dwarf ellipticals 102 104 106 108 1010 1012 stellar mass [ M ] 38 ⊙ Pavel Kroupa: University of Bonn Pressure / random-motion supported stellar systems Dabringhausen et al. 2012 TDGs coincide with 4 10 dE / dSph satellites 103 galaxies with 102 dark matter = galaxies w/o dark matter 101 ! projected half-light radius [ pc ] GCs / UCDs elliptical galaxies 100 observed TDGs numerical calculations 102 104 106 108 1010 1012 stellar mass [ M ] 39 ⊙ Pavel Kroupa: University of Bonn Therefore if the SMoC is valid then . 40 Pavel Kroupa: University of Bonn Thus in the Standard Model of Cosmology (SMoC) a galaxy must look as follows: phase-space spheroidal correlated distribution distribution + DM satellites + TDG satellites have different properties 41 Pavel Kroupa: University of Bonn The Dual Dwarf Galaxy Theorem must be true if the SMoC is true : The Dual Dwarf Galaxy Theorem : E V Kroupa 2012, 2015 SMoC ⇒ Type A dwarfs Type B dwarfs with Dark Matter (DM) TDGs w/o DM spheroidal correlated in distribution phase-space If only one type exists then the Dual Dwarf Galaxy Theorem is falsified. Is there any evidence for the co-existence of two types of dwarf galaxy ? 42 Pavel Kroupa: University of Bonn The phase-space distribution of satellites on scales of 100-300kpc (no role of baryonic physics on these scales) 43 Pavel Kroupa: University of Bonn MW satellites are in a disk-like configuration: (Kroupa, Theis & Boily 2005) 44 Pavel Kroupa: MW satellites are in a disk-like configuration: (Kroupa, Theis & Boily 2005) 45 Pavel Kroupa: ==> incompatible with expected spheroidal distribution (Kroupa, Theis & Boily 2005) THE largest (unsolvable) problem in the SMoC ! 46 Pavel Kroupa: Andromeda Milky Way Ibata et al. 2013, 2014 Pawlowski & Kroupa 2013 47 Pavel Kroupa: University of Bonn Pawlowski, Kroupa & Jerjen (2013 MNRAS) How can the MW and Andromeda satellite systems be so correlated, if they are sub-halos falling-in individually ? 48 Pavel Kroupa: University of Bonn Pawlowski, Kroupa & Jerjen (2013 MNRAS) "The discovery of symmetric structures in the Local Group" A frightening symmetry 49 Pavel Kroupa: University of Bonn Other, extra-galactic, phase-space correlated distributions of satellite systems. Are the Milky Way & Andromeda unique or extreme outliers ? 50 Pavel Kroupa: University of Bonn Bournaud et al. (2007, Science) observed model 51 Pavel Kroupa: University of Bonn 52 Pavel Kroupa: University of Bonn NGC 5557 (post-interaction 2-3 Gyr) 200 kpc ≈ dIrr dIrr Text dIrr (Kroupa et al. 2010) 53 Pavel Kroupa: University of Bonn The formation of faint dwarf galaxies in the interaction between two spirals (NGC xxxx) Credit: Martinez-Delgado (ZAH) and Adam Block (MtLemmon Obs) 54 Pavel Kroupa: University of Bonn GALEX image (NGC xxxx) From: Martinez-Delgado (ZAH) 55 Pavel Kroupa: University of Bonn Significant excess of anti-correlated satellites Ibata, Ibata et al. (2014 Nature) Ibata et al. (2015, ApJ) : Cautun et al. (2014) http://xxx.lanl.gov/abs/1410.7778 Excess is evident on scales 100-200kpc around host galaxies, host just like the about 200 kpc VPOS & GPoA. 56 Pavel Kroupa: University of Bonn Remember : Kroupa 2012, 2015 The Dual Dwarf Galaxy Theorem must be true if the SMoC is true : The Dual Dwarf Galaxy Theorem : V SMoC ⇒ E Type A dwarfs Type B dwarfs with DM TDGs w/o DM spheroidal correlated in distribution phase-space consistency check next . 57 Pavel Kroupa: University of Bonn Is there any solution of this in terms of primordial (DM-dominated) dwarfs ? 58 Pavel Kroupa: University of Bonn Wu & Kroupa 2014 A 10^8 Msun pre-infall satellite ought to have had a DM halo mass > 10^10 Msun such that its orbital decay time would be short.
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