The Milky Way Nuclear Star Cluster beyond 1 pc Anja Feldmeier, Nadine Neumayer, Anil Seth, Rainer Schödel, P. T. de Zeeuw, Nora Lützgendorf, C. J. Walcher, Shogo Nishiyama, Markus Kissler-Patig Oct. 1, 213 Anja Feldmeier
Nuclear Star Clusters (NSCs) Milky Way NGC 4395 Detected in 5% to 75% of all galaxies Half-light radius 2-5 pc Dynamical mass 1 6-1 7 M sun Complex SF history Scaling relations with galaxy properties Some contain a MBH NGC 4244 Oct. 1, 213 Anja Feldmeier 2
Nuclear Star Clusters (NSCs) Oct. 1, 213 Anja Feldmeier 3
Kinematic data set ISAAC long slit spectrograph Central field: ~4 x3.5 + 6 fields of 2 x16 size Oct. 1, 213 Anja Feldmeier 4
Kinematic data set ISAAC long slit spectrograph Central field: ~4 x3.5 + 6 fields of 2 x16 size Oct. 1, 213 Anja Feldmeier 5
Kinematic data set ISAAC long slit spectrograph Central field: ~4 x3.5 + 6 fields of 2 x16 size ~2.29 2.41 micron, spectral resolution 68 km/s Oct. 1, 213 Anja Feldmeier 6
Kinematic data set Full area 4 x 3.5 ~ 9.6 x 8.4 pc Binning to 2.22 x 2.22 Oct. 1, 213 Anja Feldmeier 7
Kinematic data set Full area 4 x 3.5 ~ 9.6 x 8.4 pc Binning to 2.22 x 2.22 Foreground stars removed: 2MASS point source catalog (Skrutskie et al. 26) & SIRIUS/IRSF catalog (Nishiyama et al. 26) Only Stars with 1.5<H-K<3.5 in cube (Schödel et al. 21) Oct. 1, 213 Anja Feldmeier 8
H 2 gas emission Gaussian fit to H 2 emission line at 2.466 µm 1- Q(1) Velocity Flux 4 4 2 2 13 km/s -93 km/s -2-2 -4-4 -6-1 -5 5 1-6 -1-5 5 1 Velocity [km/s] lg (maximum flux) -11. -82.5-55. -27.5. 27.5 55. 82.5 11. -1.3-1.14 -.98 -.81 -.65 -.49 -.33 -.16. Oct. 1, 213 Anja Feldmeier 9
H 2 gas emission Gaussian fit to H 2 emission line at 2.466 µm 1- Q(1) Velocity Velocity dispersion 4 4 2 2-2 13 km/s -93 km/s -2 > 9 km/s -4-4 -6-1 -5 5 1-6 -1-5 5 1 Velocity [km/s] Velocity dispersion [km/s] -11. -82.5-55. -27.5. 27.5 55. 82.5 11.. 11.25 22.5 33.75 45. 56.25 67.5 78.75 9. Oct. 1, 213 Anja Feldmeier 1
H 2 gas emission Gaussian fit to H 2 emission line at 2.466 µm 1- Q(1) 25 [µm] 2.42 2.44 2.46 2.48 2.41 1 [µm] 2.42 2.44 2.46 2.48 2.41 8 Flux 2 Flux 6 4 15 2 96 98 1 12 pixel 96 98 1 12 pixel Oct. 1, 213 Anja Feldmeier 11
Stellar CO absorption ppxf fit to absorption lines (Cappellari & Emsellem 24) High resolution spectra (Wallace & Hinkle 1996) convolved to lower resolution Oct. 1, 213 Anja Feldmeier 12
Stellar CO absorption Comparison to previous results (McGinn et al. 1989) 1 r (parsec) -4-2 2 4 2 r (parsec) -4-2 2 4 5 15 V (km/s) -5 σ (km/s) 1-1 ISAAC data ISAAC data, forground stars removed McGinn et al. 1989-15 -1-5 5 1-1 -5 5 1 r () r () Oct. 1, 213 Anja Feldmeier 13 5
Stellar CO absorption Voronoi binning (Cappellari & Copin 23) effect of binning 15 Velocity 12 15 Velocity dispersion 25 9 219 1 5 Velocity [km/s] 6 3-3 -6 1 5 Velocity dispersion [km/s] 188 156 125 94 63-9 31-5 -1-5 5 1-12 -5-1 -5 5 1 S/N =2, resolution ~3.5 or.14 pc Equivalent to Galaxy at ~29 kpc distance observed with.1 resolution Oct. 1, 213 Anja Feldmeier 14
Stellar CO absorption Voronoi binning (Cappellari & Copin 23) effect of binning 15 Velocity 12 15 Velocity dispersion 25 9 219 1 5 Velocity [km/s] 6 3-3 -6 1 5 Velocity dispersion [km/s] 188 156 125 94 63-9 31-5 -1-5 5 1-12 -5-1 -5 5 1 S/N =4, resolution ~12 or.5 pc Equivalent to Galaxy at ~1 Mpc distance observed with.1 resolution Oct. 1, 213 Anja Feldmeier 15
Stellar CO absorption Voronoi binning (Cappellari & Copin 23) effect of binning 15 Velocity 12 15 Velocity dispersion 25 9 219 1 5 Velocity [km/s] 6 3-3 -6 1 5 Velocity dispersion [km/s] 188 156 125 94 63-9 31-5 -1-5 5 1-12 -5-1 -5 5 1 S/N =6, resolution ~2 or.8 pc Equivalent to Galaxy at ~1.6 Mpc distance observed with.1 resolution Oct. 1, 213 Anja Feldmeier 16
Stellar CO absorption effect of foreground stars 15 Velocity 12 15 Velocity dispersion 25 9 219 1 5 Velocity [km/s] 6 3-3 -6 1 5 Velocity dispersion [km/s] 188 156 125 94 63-9 31-5 -1-5 5 1-12 -5-1 -5 5 1 S/N =4, including foreground stars Oct. 1, 213 Anja Feldmeier 17
Stellar CO absorption effect of foreground stars 15 Velocity 12 15 Velocity dispersion 25 9 219 1 5 Velocity [km/s] 6 3-3 -6 1 5 Velocity dispersion [km/s] 188 156 125 94 63-9 31-5 -1-5 5 1-12 -5-1 -5 5 1 S/N =4, after foreground star correction Oct. 1, 213 Anja Feldmeier 18
Stellar CO absorption 1-dim profile Circular bins around Sgr A* V rms = SQRT(V 2 +σ 2 ) Oct. 1, 213 Anja Feldmeier 19
Stellar CO absorption 1-dim profile r (parsec).1 1. 1. 2 with foreground stars without foreground stars with IRS7 V RMS (km/s) 15 1 5 1 1 1 1 r () Circular bins around Sgr A* V rms = SQRT(V 2 +σ 2 ) Oct. 1, 213 Anja Feldmeier 2
Photometry from Spitzer/IRAC survey 4.5µm image (Stolovy et al. 26) Dust and extinction corrected (Poster by Devaky Kunneriath) Oct. 1, 213 Anja Feldmeier 21
Photometry from Spitzer/IRAC survey Multi-Gaussian expansion fit (Cappellari 22) r (parsec).1.1 1. 1. 1. 1 6 1 5 L O /parsec 2 1 4 1 3 1 2 1 1 major axis 1 1 1 1 1 r () Oct. 1, 213 Anja Feldmeier 22
Photometry from Spitzer/IRAC survey Multi-Gaussian expansion fit (Cappellari 22) r (parsec).1.1 1. 1. 1. 1 6 1 5 L O /parsec 2 1 4 1 3 1 2 1 1 1 major axis minor 1 1 1 1 r () Oct. 1, 213 Anja Feldmeier 23
Photometry from Spitzer/IRAC survey Multi-Gaussian expansion fit (Cappellari 22) r (parsec).1.1 1. 1. 1. 1 6 1 5 L O /parsec 2 1 4 1 3 1 2 1 1 1 major axis minor axis upper error lower error 1 1 1 1 r () Oct. 1, 213 Anja Feldmeier 24
Axisymmetric Jeans models Jeans Anisotropic MGE dynamical models (JAM, Cappellari 28) Inclination=9, constant anisotropy β constant M/L 2 r (parsec).1 1. 1. V RMS (km/s) 15 1 Best fit with χ 2 = 21.84, β =.6 (radial), M/L 4.5µm =.32 +.28 -.17 M sun /L 4.5µm,sun M BH = 2.e6 ±1.e6 M sun 5 1 1 1 r () Oct. 1, 213 Anja Feldmeier 25
Conclusions First map of stellar velocities of the NSC Foreground star removal has no big influence on the results Result of black hole mass fit from Jeans model is largely consistent with black hole mass from direct measurements Black hole mass is too low à do we underestimate black hole masses in other Galaxies? Radially varying M/L can fit the required black hole mass à constrain the M/L with stellar population analysis using KMOS data Oct. 1, 213 Anja Feldmeier 26