An update on SMBHs in UCDs

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1 An update on SMBHs in UCDs Steffen Mieske ESO Chile MODEST 17 meeting Prague Sept , 2017 Seth Voggel Chilingarian Afanasyev Neumayer Frank Baumgardt Hilker Lützgendorf

2 Hilker

3 UCD UCDs are believed to be Massive star clusters (e.g. Fellhauer & Kroupa 2002,2005, Mieske+ 2002) and/or Tidally threshed galaxies (Bekki et al. 2003, Drinkwater et al. 2003, Pfeffer & Baumgardt 2013) Normal dwarf UCDs Misgeld & Hilker 2011

4 UCD Normal dwarf Michael Hilker

5 Seeing limited spectroscopic observation Measure global velocity dispersion Dynamical modelling using HST surface brightness profiles Include slit effects

6 Elevated dynamical M/L of UCDs UCDs GCs Mieske et al Dark mass Dark mass No dark mass Literature: McLaughlin et al. 2005, Hasegan et al. 2005, Evstigneeva et al. 2007, Hilker et al. 2007, Mieske et al & 2013, Chilingarian & Mamon 2008, Taylor et al. 2010, Chilingarian et al. 2011

7 Normal dwarf UCDs Misgeld & Hilker 2011

8 Mieske et al. (2013): calculate central BH masses in UCDs needed to elevate M/L (Mieske, Frank, Baumgardt, Luetzgendorf, Neumayer, Hilker, A&A 2013, 558, 14) Typical inferred BH mass fraction is 10% of UCD mass

9 Prediction: Massive UCDs should have ~10% relative BH masses Mieske McConnell & Ma 2013 UCDs Luetzgendorf+ 2013

10 Prediction: Massive UCDs should have ~10% relative BH masses Mieske McConnell & Ma 2013 UCDs Luetzgendorf Massive BHs in UCDs would thus be relics of massive UCD progenitors. (Bekki et al. 2003, Pfeffer & Baumgardt 2013)

11 To resolve the kinematical signature of an SMBH in UCDs, one needs AO assisted spectroscopy

12 Joint Gemini North & VLT campaign to resolve UCD dynamics [PIs Seth, Mieske] M60 UCD1

13 NGC 4647! M60! M60-UCD1! 1 /80 pc!

14 Resolving the BH sphere of influence in M60-UCD1 (Seth et al. Nature 2014) Velocity Dispersion Data M60 UCD Model

15 Resolving the BH sphere of influence in M60-UCD1 (Seth et al. Nature 2014) Best fit Schwarzschild model M_BH = 2.1 * 10 7 M * Case of no BH rejected at 4σ à A supermassive black hole with 15% of the UCD mass M60 UCD

16 Jeans models consistent with Schwarzschild models and isotropy

17 M60 UCD black hole in context M60 UCD Offset from the L-BH relation suggests significant tidal stripping Progenitor Bulge of ~10 10 M *

18 What is the occupation fraction of SMBHs in UCDs? Gemini+VLT campaign (PIs Seth, Mieske) Goal: constrain central BH masses in 11 nearby UCDs (<20 Mpc) à Do SMBHs in UCDs contribute significantly to the local SMBH density? à Which fraction of UCDs originates from galaxies?

19 What is the occupation fraction of SMBHs in UCDs? Gemini+VLT campaign (PIs Seth, Mieske) Goal: constrain central BH masses in 11 nearby UCDs (<20 Mpc) à Do SMBHs in UCDs contribute significantly to the local SMBH density? à Which fraction of UCDs originates from galaxies?

20 New UCD BH results, 1 SINFONI+LGS of CenA UCDs CenA UCD 330 (HST archival) CenA UCD 320 (ACS, courtesy A. Romanowsky) Voggel et al. (2017, in prep): No strong kinematical indication for SMBH in CenA UCDs

21 Ahn et al. (2017): SMBHs confirmed in two Virgo UCDs New UCD BH results, 2 M BH = * 10 6 M * Gemini-N NIFS M BH = * 10 6 M *

22 New UCD BH results, 3 SINFONI+LGS of Fornax UCD 3

23 New UCD BH results, 3 SINFONI+LGS of Fornax UCD 3 PRELIMINARY radial velocity dispersion profile: - New SINFONI data, PSF is combination of 0.15 core and 1.0 wing - Seeing limited FLAMES data from Frank et al. (2011), PSF ~0.55 Afanasyev et al. 2017, in preparation

24 New UCD BH results, 3 SINFONI +LGS of Fornax UCD 3 PRELIMINARY radial velocity dispersion profile: - New SINFONI data, PSF is combination of 0.15 core and 1.0 wing - Seeing limited FLAMES data from Frank et al. (2011), PSF ~0.55 Mass of SMBH = *106 M * (~5% of UCD mass) Afanasyev et al. 2017, in preparation: SMBH detected at 98% confidence

25 What is the occupation fraction of SMBHs in UCDs: Update Q3/2017 SMBH occupation fraction: 4 out of 6 100% for UCD mass ~10^8 0% for UCD mass ~10^7

26 What is the occupation fraction of SMBHs in UCDs: Update Q3/2017 SMBH occupation fraction: 4 out of 6 100% for UCD mass ~10^8 0% for UCD mass ~10^7 Pfeffer et al. (2016) Number of stripped nuclei expected from simulations vs. number of observed CSSs

27 Summary 1. UCDs (compact stellar systems more massive than ωcen) are a mixed bag of objects consisting of massive star clusters and tidally stripped dwarf galaxies. 2. Elevated dynamical M/L ratios of massive UCDs suggest dark mass 3. SMBH occupation fraction of UCDs supports a scenario where: UCDs with masses > M * mostly are tidally stripped galaxies UCDs with masses <10 7 M * mostly are massive star clusters This is consistent with theoretical studies on the number ratio between tidally threshed naked nuclei and star clusters as f(m)

28 Outlook Complete ongoing SMBH survey in UCDs And start going after UCD progenitors Investigate alternative explanations for elevated dynamical M/L of UCDs e.g. global IMF variation or central dark remnants bad measurements... Stellar population and kinematical trends among large samples of GCs & UCDs

29 Outlook?

30 Pechetti et al. (2017, almost accepted): Constraining SMBH masses in low mass ETGs (UCD progenitors) based on ATLAS 3D

31 Announcement of opportunity at the VLT: MUSE-AO in narrow field mode to come soon 7 x7 IFU in the optical with high perfomance AO ( resolution) Science verification planned for mid 2018

32 Announcement of opportunity at the VLT: MUSE-AO in narrow field mode to come soon 7 x7 IFU in the optical with high perfomance AO ( resolution) Science verification planned for mid 2018

33 Announcement of opportunity at ESO: ESO fellowships Garching & Chile Deadline October 15 Fast track your scientific career