A M BLACK HOLE IN NGC 1277 FROM ADAPTIVE OPTICS SPECTROSCOPY. WALSH et al Akiyama Group M1 Genki Suzuki

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1 A M BLACK HOLE IN NGC 1277 FROM ADAPTIVE OPTICS SPECTROSCOPY WALSH et al Akiyama Group M1 Genki Suzuki

2 Introduction NGC 1277 is thought to harbor one of the most massive black holes in the Universe MBH= M (van den Bosch et al. 2012) NGC 1277 has been called a "relic of the early universe because - old star populations : ages>10gyr (Ferré-Mateu et al. 2015) - similarity to z~2 galaxies small size (effective radii, Re, below 3 kpc) large stellar velocity dispersions ( km/s) - and

3 Introduction NGC1277 is significant positive outliers from the local M BH L bul relation (however, this galaxy consists with the M BH σ relation) (van den Bosch et al. 2012)

4 Introduction previous study van den Bosch et al. (2012) M BH = M Emsellem (2013) M BH = M Yildirim et al. (2015) M BH = M (possibly lower value) Kormendy & Ho (2013) using stellar-dynamical models M BH =( ) 10 9 M and low-resolution spectroscopic observations This work resolved the uncertainties in the NGC 1277 black hole mass with high-resolution observations

5 AO NIF Observations the Gemini North telescope ALTAIR (ALTtitude conjugate Adaptive optics for the InfraRed) Near-infrared Integral Field Spectrometer (NIFS ) - with H+K filter and K grating (center 2.2μm) - target : NGC1277 (total 2 hours) nearby star and A0 V star (for making PSF models) K-and M-giant/supergiant star each pixel s wavelength stored in each data-cube IFU natural seeing with AO

6 Luminosity Mass Model the two-dimensional (2D) light distribution ( presented in van den Bosch et al. (2012) ) It was constructed from an archival HST Advanced Camera for Surveys (ACS) image with the F550M filter (total integration time of 2439 s, and a spatial scale of pixel 1. ) The light distribution is described using the Multi-Gaussian Expansion (MGE) method (Monnet et al. 1992; Emsellem et al. 1994)

7 High Angular Resolution Stellar Kinematics Voronoi binning method (Cappellari & Copin 2003) determining the optimal balance between S/N and bin size NIFS data cubes -> new spatial bins Example of Voronoi bining This figure is NOT data of this work (From

8 High Angular Resolution Stellar Kinematics Penalized pixel fitting (ppxf) method (Cappellari & Emsellem 2004) - measuring the line-of-sight velocity distribution(losvd) in each spatial bin - parametrizing the LOSVD in terms of the radial velocity (V), the velocity dispersion (σ), the two Gauss-Hermite moments: h 3 (: asymmetric deviation) h 4 (: symmetric deviation) Measuring the dynamics of later-type giants and supergiants, via (2 0) 12 CO and (3 1) 12 CO absorption lines

9 NIFS PSF Measurement Modeling NIFS PSF as two/four circle 2D Gaussians -> Since the NIFS PSF is a vital input into the dynamical models when measuring M BH Dynamical Models the mass distribution of NGC 1277 is constrained by using the three-integral, triaxial, orbit-based models from van den Bosch et al. (2008) the galaxy s gravitational potential is constructed from the combination of the black hole, mass-to-light ratio, and a Navarro-Frenk-White (NFW; Navarro et al. 1996) dark matter halo V-band stellar mass-to-light ratio (Υ V ) that remains constant with radius With this synthetic datacube we performa wavelength-by-wavelength convolution with the PSF Image of convolution

10 Result 3σ 1σ Fitting stellar-dynamical models to the point-symmetrized NIFS kinematics ±1σ M BH =(4.9±0.2) 10 9 M, Y V =9.3±0.4Y <-- Best-fit model +1.2 ±3σ M BH =(4.9 ) M, Y V = Y reduced χ 2 is 0.7

11 Result the two Gauss-Hermite moments: h 3 (: asymmetric deviation) h 4 (: symmetric deviation) top : Observed NIFS kinematics bottom : The best-fit stellar dynamical model

12 Result Three Tests 1) The best-fit value when assuming a different PSF models comparison between two-gaussian PSF model (best-fit) and four-gaussian PSF model - M BH = M (22% ), Y V =8.0Y (14% ) 2) Using unsymmetrized kinematics - M BH = M (18% ), Y V =8.8Y (5% ) 3) Adopting a different ppxf contimuum-correction changing additive/multiplicative Legendre polynominal of parameter - M BH = M (14% ), Y V =10.0Y (8% ) The final uncertainties are determined from those tests M BH =(4.2±1.6) 10 9 M, Y V =9.3±1.6Y (1σ)

13 The primary observation of NGC Hobby-Eberly Telescope(11.1 x 9.8 m) with Low Resolution Spectrograph (1 -wide slit, ) - 3.5m telescope at Calar Alto Observatory with the Postdam Multi Aperture Spectrograph in the Pmas fiber PAcK (PPAK) mode -> those observations are low-resolution spectroscopic observations CAO HET

14 Result Comparison to Previous M BH Measurements Since NIFS isn t match HET and PPAK, The combination NIFS+HET, NIFS+PPAK are fitted dynamical model NIFS+HET this work (NIFS) HET PPAK M BH = M, Y V =10.3Y (reduced χ 2 ) ~ 0.8 NIFS+PPAK M BH = M, Y V =9.8Y (reduced χ 2 ) ~ 0.8 ->NIFS+HET and NIFS+PPAK models agree with NIFS best-fit model

15 Discussion - Comparison to Previous M BH Measurements Observed NIFS kinematics Best-fit model (this work) expectation from M BH -L bul relation van den Bosch et al. (2012)

16 Discussion NGC1277 is similar to black hole monsters (Kormendy & Ho (2013) ) These early-type galaxies are small, rotating, high velocity dispersion and positively outliers from M BH L bul relations

17 Discussion Explanations for the presence of these over-massive black holes 1) the galaxies are relics of the z 2 quiescent galaxies - old stellar populations (ages 10 Gyr) (Ferré-Mateu et al. 2015) - outliers from the local mass-size relation (Shen et al. (2003) ) -> maybe they reflect a previous time when galaxies harbored over-massive black holes, and the growth of host galaxies had yet to catch up 2) these objects are simply unusual, and are found in the tails of a distribution between black hole masses and host galaxy properties.

18 CONCLUSION They has obtained Stellar Kinematics of the nearby S0 galaxy NGC 1277 with Gemini/NIFS assisted by AO. They obtains the black hole mass of M BH =(4.9±1.6) 10 9 M by using stellar dynamical models this result is consistent with the previous studies (lower 3σ limit of M from van den Bosch et al. (2012) and of M from Yildirim et al. (2015) ) and NIFS+HET, NIFS+PPAK NGC 1277 could suggest that galaxies contained over-massive black holes at earlier epochs, such that the growth of black holes precedes the growth of their host galaxies.