Black hole mass measurements in AGN Polarization in

Black hole mass measurements in AGN: Polarization in broad emission lines Luka Č. Popović, Victor L. Afanasiev Astronomical Observatory, Belgrade, Serbia Special Astrophysical Observatory, Russia

The aim: Measuring supermassive black hole masses. Why?

bulge BH Black Hole - Bulge Relation Stellar disc MBH = 0. 2 % Mbulge MBH Mbulge 1. 74

Coevolution of black holes and galaxies • Starbrust and AGN starting phase • Normal galaxy AGN feedback Gas inflows • Galaxy merger Hierarchical growth Galaxy formation and evolution • AGN - quasar Growth of BH

Hierarchical Galaxy Formation AGN NG NG

AGN • AGN = central SMBH + gas

AGN model - unification Black hole Accretion of gas

Accretion of gas

Polarization in AGNs i ~ 0 , scattering ~ 0 (E ), view direct to accretion disc (E ) and jet (E ) , high polarized, synhotronic blazars i <45 , equatorial scattering> 0, (E ), Sy 1 jet (E ) i ~ 90, polar scattering> 0 (E ), “hidden” BLR in polarized ligth, Sy 2 Dusty torus, size~ 1018 cm BLR, size~1017 cm 8 M. BH, M~10 13 Rg~10 cm Accretion disk size~ 1015 cm (E||) Polarization in continuum ü radiative transfer in AD ü Synchrotron radiation in jet ü scattering by gas-dust torus Polarization in lines ü scattering by gas-dust torus ü radiative transfer in the BLR

Broad line AGNs (Sy 1) – Smith et al. 2004, polar vs equatiorial pol.

Type 1 AGN: Equatorial polarization in broad lines: (Smith et al. 2004, 2005) Broad line P. A. Broad line shapes

Measuring the mass of SMBH in galaxies Several methods (stellar dynamics, gas dynamics, masers, reverberation): Direct and indirect (see Peterson 2014 SSRev, talk of Karl Gebhardt) § §Can spectropolarimetry help?

Broad emission lines Very close to the Black hole Virialization: line widths ~ rotational velocity Very carefully subtract the continuum and narrow/satellite lines

To measure the black hole mass – v vs. R B H REC E C

Virial Mass Estimates MBH = f v 2 RBLR/G Reverberation Mapping: • RBLR= c τ t + t • v. BLR ~ FWHM Line width in variable spectrum

Broad emission lines - reverberation Very close to the Black hole Virialization: line widths ~ rotational velocity calculated from broad line widths Dimensions of BLR+. reverberation Geometry, orientation of BLR

Polarization and factor f Piotrovich et al. 2015, MNRAS, 454, 1157 Songsheng, & Wang, 2018, MNRAS, 473 L, 1 Polarization in line – broad component (PKS 2004 -447) Baldi et al. , 2016, MNRAS, 458 L, 69

New method, using polarization angle (φ) - Afanasiev & Popovic 2015, Ap. J, 800 L, 35; Savic et al. 2018 A&A equatorial scattering

Polarizarion in the broad H (BLR). Equatorial scattering - idea log(V/c) V 1 PA V 2 V 3 log[tg(φ)] PA shape Rsc V 1 V 2 V 3 V

Polarization & SMBH mass • Observations with 6 m telescope (SAO RAS) + SCORPIO (see Afanasiev et al. 2014, 2015; Afanasiev & Popovic 2015) • Theory – model with STOKES (Savic et al. 2018)

Observations STOKES PARMATERS STELLAR STOKES PARMATERS

Observations continuum and line H

V vs. tan(φ) – direct evidence of Keplerian motion in the BLR of Mrk 6 (Afanasiev et al. 2014) -0. 5

Observed P. A, Afanasiev & Popovic 2015

log(V/c) a 0 log[tan(φ)]

Estimation size Rsc of the dusty torus M. Kishimoto et al. , A&A 527, A 121 (2011) Direct measurement from the near IR (2 -3 mkm) Delay in variability btw. K and V-band. or using relations

SMBH mass measurements method given in Afanasiev & Popovic 2015, Ap. JL, 800, L 35

Log(M) from polarization Comparison polarization and reveberation Log(M) from reverberation

BH mass VS central velocity dispersion Tremaine et al. , Ap. J, 2002, 574, 740 (our data - blue full circles) stars masers gas polarization }

Theory confirmed observation, model with STOKES see Savic et al. 2018, A&A accepted (ar. Xiv: 1801. 06097) anticlockwise

The method: adventages and problems 1. 2. 3. One epoch SP observation of broad lines Broad lines from the UV to optical can be used => estimate BH masses of AGN with different shift on a consistent way Virialization can be explored (it is not taken ‘apriori’ as in RM) Problem with ISM polarization Problem with estimates of the inner torus radius The equatorial polarization should be dominant Thank you for your attention