Tracing High-Redshift Black Holes with ALMA in Atomic Cooling Lines Bachelor Thesis Astronomy

Nowadays it is known that galaxies with Super Massive Black Holes (SMBH), ≥ 10 M , do exist [Haring & Rix (2004)]. However, the process behind the formation of these SMBH is not quite well understood. A SMBHmust be formed through accretion from (less) massive seed black holes in the early universe, to become like the present-day SMBHs which are at this moment in the nuclei of a lot of galaxies [Bromm & Loeb (2003)]. If we are able to detect these young high-redshift black holes we make a huge step forward in the understanding of this process. X-rays are produced by the accretion of mass onto the black holes. Spaans & Meijerink (2008) already showed that the molecules CO and H2 can be used to trace this young population of accreting massive black holes through the X-ray irradiation of ambient gas. In this small research a miniquasar is considered at high-redshift, which for simplicity contains a black hole that radiates at the Eddington luminosity. NGC 1068 is taken as a reference system and is hypothetically put at high-redshift, e.g. z = 10. In this work it is investigated how one can observe accreting black holes at redshifts 5 ≤ z ≤ 10 through the atomic cooling lines [CII]158 and [OI]63 μm. The atomic cooling lines are driven by the X-rays and are accessible to ALMA, the Atacama Large Millimeter/submillimeter Array. ALMA is now being built and will be fully operational in 2013. Moreover, using the Press & Schechter formalism the number of expected halos which one can detect with ALMA is given for completeness [Schleicher et al. (2008)].