The Future of Direct Supermassive Black Hole Mass Measurements Dan Batcheldor Rochester Institute of Technology - The Role of SMBHs measurements. - Current Status of SMBH masses. - Mass estimate techniques. - Observational requirements. - Current and future abilities.

Dan Batcheldor, RIT, Astro20203 The Role of SMBHs Energy output, variability and longevity of AGN require accretion onto a SMBH. QSO number density higher in the past, expect to find relic SMBHs in local quiescent galaxies. Observed correlations between SMBH and host bulge properties. Correlations used to calibrate secondary techniques for higher redshift SMBH mass estimates. See review by Ferrarese & Ford (2005).

Dan Batcheldor, RIT, Astro20204 Current Status Only 3 cases that require a SMBH: NGC 4258, Circinus, Milky Way = 3.7(  0.2) x 10 6 M  ~ 30 direct mass estimates (10 6 M  x 10 9 M  ) 25 with resolved spheres of influence up to 240 Mpc Mostly early type hosts, mostly observed with HST. Modes: ~ 10 8 M , ~ 20 Mpc. Estimates from different methods may not be consistent.

Dan Batcheldor, RIT, Astro20205 Mass Measurement Techniques Resolved Proper Motions –Milky Way only 22 GHz water masers (NGC 4258) –Alignment issues –AGN required Asymmetric Fe K  emission line (NGC 3516) –AGN required –Rev map, but crossing times < integration times Nucleated disk gas dynamics Stellar dynamics

Dan Batcheldor, RIT, Astro20206 Mass Measurement Techniques Gas Dynamics Assumes rotating nuclear gas/dust disk.  tot =  stars +  bh Relies on bright emission lines. Keplerian rotation relatively easy to model and positive signature of SMBH. Arguments over non-gravitational forces. Nuclear disks not present in all galaxies. Inclination unconstrained in many cases.

Dan Batcheldor, RIT, Astro20207 Mass Measurement Techniques Stellar Dynamics 2 - integral models (Jeans equations). 3 - integral models (orbital super-positioning). Observed kinematics are purely gravitational. Applicable to all galaxies. Requires the use of faint stellar absorption lines at low surface brightness. Effected by extinction. Systematic uncertainties.

Dan Batcheldor, RIT, Astro20208 Observational requirements Gas and stellar dynamics complementary. 2D kinematics essential in both cases. High sensitivity (STIS needs 100 orbits for S/N 50 in M87 continuum). High resolution. Sphere of influence of 10 8 M  at 10 Mpc (   = 200 km s -1 ) is ~ 0.2 arcsec.

Dan Batcheldor, RIT, Astro20209 Equate diffraction limit to sphere of influence. Evaluate for = 5200, 6563 & 8500Å. Assume modal distance values from current SMBH mass estimates. Consider sensitivities… Current abilities

Dan Batcheldor, RIT, Astro Future abilities JWST + NIRSpec. –At 9500Å R = 35, at 1.9  m R = 2200 (135 km s -1 ) + IFU –At 8500Å R = 39, at 2.3  m R = 2500 (120 km s -1 ) + IFU JWST + MIRI. –At 7.6  m R = IFU 16 m + ?? TMT + ??

Dan Batcheldor, RIT, Astro Summary Galaxy and SMBH formation and evolution intimately linked. 30 mass estimates over limited ranges. Gas and stellar dynamics are complimentary methods. HST is exhausted, JWST limited abilities To fully explore the M  -   plane –30+ m diffraction limited facility –High spectral resolution in optical and near-mid IR

Dan Batcheldor, RIT, Astro202012