Astrophysics
Observational and theoretical evidence supports the idea that the
accreting mass forms an accretion disk, and that the UV/optical
emission of the QSO could be coming directly from the surface of the
accretion disk itself. Additionally, in about 10% of QSOs,
high-velocity outflows (in the order of thousands of kilometers per
second) are detected through the presence of Broad Absorption Lines
in their spectra. We are exploring, through the development of
computational models, the scenario in which these QSO outflows are
coming directly from the accretion disk.
Observational Evidence for
Accretion Disk in QSOs
Note the good
agreement of observational data (blue) with theoretical accretion
disk calculations (green).
Blue: QSO “average”
spectrum.
Green: Theoretical
accretion disk spectra for different “characteristic” temperatures
Observational
Evidence for Accretion Disk in QSOs
Note the good
agreement of observational data (gray) with theoretical accretion
disk calculations (black-line).
Gray: QSO “average”
residual spectrum; that is the “difference” spectra as the QSO
varies in luminosity.
Black line:
Best
fit accretion disk residual spectrum.
Black dotted line:
Best fit blackbody spectrum.
Simple
Schematic Representation of the Accretion Disk Wind Scenario for QSOs
Note that X-ray emission, within this scenario, is
being emitted within the inner radius of the accretion disk closer to the black
hole.
QSO disk wind computational results: velocity field
vectors superimposed with density contours.
CIV 1549Å Spectral Line
Profiles Calculated from Computational Models
(Assuming Single Scattering)
Research in Astrophysics includes the
computational modeling of flows from QSOs (Quasars).
QSOs are extremely luminous objects and
thus are the objects that we can see farthest away. They are found
at the center of galaxies, have a size comparable to our Solar
System, and emit more light than their “host” galaxies. This large
amount of emission from a relatively small region can be accounted
for by mass accreting (“falling towards”) onto a supermassive black
hole (a black hole of millions to billions of solar masses).
