טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentCarmit Lahav
SubjectCorrelations of Black Hole Mass with Host Galaxy Properties
DepartmentDepartment of Physics
Supervisor Full Professor Soker Noam
Full Thesis textFull thesis text - English Version


Abstract

This thesis project deals with relations between the galaxy's super massive black hole mass (SMBH) and other galaxy parameters. The relations themselves are suggested to arise either from mergers of small galaxies or from a feedback mechanism between the accreting SMBH and the star formation process in the galaxy. I work on a wide sample of galaxies and present the relations calculated by a least squares estimator which considers errors in both axes. I show that the studied relations are compatible with a power law and are very close to being linear. I examine the scatter in the correlation between black hole masses and their host bulge masses, and find that the increase of the scatter with mass suggests that mergers alone cannot produce the observed correlation. A simple merger scenario of small galaxies leads to a proportionality relation between the black hole and bulge masses with intrinsic scatter increasing along the ridge line of the relation as the square root of the mass. By examining a sample of 87 galaxies I find that the scatter increases with mass more rapidly than expected from the merger-only explanation. This result precludes the claim that mergers are the only or most dominant reason for the relations. I do not dispute that mergers play a role, but the results favor a universal feedback mechanism that works on all scales.