Frontiers in Science #7 Co-evolution of Galaxies and Massive Black Holes in the Universe Masayuki Akiyama (Astronomical Institute) 2009/11/25

Today’s lecture 1.Astronomy, Astrophysics : Big Picture, recent discoveries 2.Astronomy methodology 3.What are galaxies ? 4.Formation and evolution of galaxies and black holes 5.Future prospects

Astronomy, Astrophysics : Big Picture We would like to understand our “origin”, where are we from ? Origin of the universe Origin of galaxies Origin of the solar system

Astronomy, Astrophysics : Big Picture 1.Origin of the universe What are “dark matter”, “Dark energy”. Dark energy accelerate the expansion of the universe ! Dark matter dominate the dynamics of galaxy groups Dark energy dominate the dynamics of the current universe. Overlapping particle physics. From eso.org/~bleibund/papers/EPN/epn.html

Astronomy, Astrophysics : Big Picture 1.Origin of the universe What are “dark matter”, “Dark energy”. Dark energy accelerate the expansion of the universe ! Dark matter dominate the dynamics of galaxy groups Dark energy dominate the dynamics of the current universe. Overlapping particle physics. From

Astronomy, Astrophysics : Big Picture 2. Origin of galaxies First galaxies, reionization of the universe. Growth histories of galaxies and super massive black holes Physical interplay between galaxies and SMBHs ! From

The deepest image of the sky From

Astronomy, Astrophysics : Big Picture 3.Origin of the solar system Discovery of extra-solar planets ! Search for “earth”-like planets around stars. Search for biological marker in their light. Overlapping earth science, biology in future. From

Astronomy, Astrophysics : Methodology How? Basically we are “passive” (of course we are active in research !)… 1.Receiving electromagnetic wave Various wavelength covering Radio – IR – Visible – UV – X-ray - Gamma-ray (In future with gravitational wave ?) 2.Ground-based or Satellite Depends on wavelength (= atmospheric transmittance and atmospheric emission) 3.Imaging or Spectroscopy Imaging: deeper, color, shape, deeper than spe. Spectroscopy: many “lines”, rich physical info.

Astronomy, Astrophysics : Methodology How?

Ground-based telescope : Subaru telescope At the top of Mauna Kea in Hawaii

Astronomy, Astrophysics : Methodology How? Radio Optical-NIRX-ray

Galaxies in the local universe Local universe = around our Milky-Way galaxy (the Galaxy). Our understanding of galaxies and SMBHs in the local universe. Where are we ? SMBHs at the centers of the galaxies.

Where are we now ? Based on the observations of the distribution of hydrogen gas emission on sky, it is thought that Solar system belongs to a spiral galaxy like this and it is located in the middle of the disk-like structure.

Milky-Way galaxy has 10^6 Msolar black hole at the center. How is it revealed ? Super Massive Black Hole

Stellar motion at the center of the MW-galaxy From These images/animations were created by Prof. Andrea Ghez and her research team at UCLA and are from data sets obtained with the W. M. Keck Telescopes.

Radio observation revealed 2.5x10^7 Msolar SMBH at the center of NGC4258 Super Massive Black Hole in other galaxies ! From From tokyo.ac.jp/kisohp2/IMAGES/extragalactic.html

M104 M(BH) = 10^8 Msolar

M87 M(BH) = 10^9 Msolar

Introduction From STSci SMBH-galaxy connection

The relation holds for smaller systems ? HST/STIS observations of a star cluster G1 in the M31 (Andromeda galaxy). The velocity dispersion at the center is 30km/s and the black hole mass is estimated to be 18000Msolar. Gebhardt et al. 2005, ApJ, 634, 1093 Gebhardt et al. 2002, ApJ, 578, L41

The mass ratio is M(galaxy-bulge) : M(BH) = 1000 : 1 The physical scale is, R(galaxy-bulge) ~ 10 kpc ~ 33,000 ly R(black-hole) ~ 10AU ~ 1.6x10^-6 ly R(black-hole dominate)~ pc ~ ly

Formation and Evolution Formation and evolution of galaxies = Statistical variation of physical properties as a function of cosmic time (redshift). 1.Basic understanding of the galaxy formation theory Movie 1: structure formation in the cold-dark matter (CDM) universe Movie 2: formation of a galaxy in the structure 2.Growth history of SMBHs.

Formation and Evolution Formation and evolution of galaxies CDM model can explain the distribution of galaxies in the local universe From From 4d2u.nao.ac.jp Simulated structure Real galaxy distribution

Catch active SMBHs in the distant universe From Some SMBHs actively accreting gas around them, they can be detected as “Active Galactic Nuclei” (“Quasar” is luminous sub population of AGNs).

Catch active SMBHs in the distant universe From This AGN-phase is thought to be the major growing-phase of the SMBHs. In the local universe the number is 1/1000 of the galaxies.

Catch active SMBHs in the distant universe They can be found using strong X-ray or radio emission. Radio Optical-NIRX-ray

Catch active galaxies in the distant universe The distance (how far away from us = how far trace back the cosmic history) can be measured with “redshift” Wavelength (angstrom=0.1nm) galaxies in the local universe galaxies at 4-billion years ago

Ueda, Akiyama et al. 2003, ApJ, 598, 886 SMBHs accretion history in the universe Number density of X-ray AGNs as a funtion of cosmic time (=redshift). Sample is divided by X-ray luminosity (brightness).

Estimate Black hole properties For each AGN, we can estimate properties of black holes using, Luminosity -> Mass accretion rate (growth rate) Line width (how fast the gas around BH is moving) -> Black hole mass

Growth history of the SMBHs inferred from the number density Marconi et al. 2004, MNRAS, 351, 169

Growth history of the SMBHs compared with that of galaxies Marconi et al. 2004, MNRAS, 351, 169 Perez-Gonzalez et al. 2008, ApJ, 675, 234

At z=1-3 Number density of AGNs ~10 times larger than in the local universe. Number density of galaxies ~10 times smaller than in the local universe. Naïve argument: !! AGN should be 100 times more common among galaxies in the redshift range !! Ueda et al Introduction: Importance of AGNs between z=1-3 Marchesini et al Number density of X-ray AGNsStellar mass density in galaxies

AGNs play more important role in distant galaxies At 2<z<4,1/3 of the high stellar mass galaxies are detected in deep Chandra image (estimated hard X- ray luminosity L(2-10keV)=10^42-10^45erg/s, i.e. Seyferts and QSOs). Yamada, Kajisawa, Akiyama et al. 2009, ApJ, 699, 1354 Squares: X-ray selected galaxies K-selected 2<z<4 (~10billion years ago) galaxies from MOIRCS Deep Survey

SMBH can be a key player Based on simple Cold-Dark-Matter galaxy formation model, more massive galaxies expected than observed. Formation of massive galaxies cannot be stopped without feed-back from AGNs (SMBHs growing process). Bower et al. 2006, MNRAS, 370, 645 Without AGN feedback With AGN feedback

In the near future, new radio observatories, ALMA and E-VLA start observations. They can detect “gas” component of the distant galaxies. Such information is necessary to understand the galaxy evolution and SMBH growth in the cosmic history. 近いFuture prospects 将来 From From

近いFuture prospects 将来 What are the “seeds” of the SMBHs ? Stellar mass black hole (~10Msolar) are too small

Latter half of the 2010s will be a era of next generation “giants”. JWST6.5m (2013?) ＋ ground-based 30m telescope (2018?-). Low-background NIR deep imaging & spectroscopy with JWST and high-spatial resolution observation with 30m telescope with Adaptive Optics will resolve the physical properties of distant galaxies as we currently observe galaxies in the local universe. Future Prospects

Why Astronomy Astrophysics ? We would like to understand our “origin”, where are we from ? Origin of the universe Origin of the galaxies Origin of the solar system If we do not explore these issues, why do human being need to exist ? I think…..