Black Hole Movies and Sounds
Movies
- The movies are currently in animated GIF format. I find they
appear nicely using QuickTime, but should also be viewable with other
media players.
- A hot spot "blob" orbiting a Kerr black hole with a/M=0.5 and a
3:1 ratio of the orbital and epicyclic frequencies
Nearly face-on (20 degree inclination)
Nearly edge-on (70 degree inclination)
- A hot spot point particle on a circular orbit around a Kerr black
hole with a/M=0.5 and inclination of 75 degrees. The strong
gravitational lensing of the black hole produces multiple images with
different Doppler shifts (not seen in the above movie where the
photons are not allowed to pass through the equatorial plane). The
black hole is surrounded by a corona of hot electrons that
inverse-Compton scatter the photons, blurring out the hot spot image
and boosting the photons to higher energy.
optical depth tau = 0 (no corona)
tau = 2
tau = 4
- For an inclination of 90 degrees, the hot spot forms an Einstein
ring when directly behind (or in front of) the black hole. Each time
the photons circle the black hole, the ring is de-magnified by a
factor of 10-100. Note the time delay for the ring images that must
circle the black hole before reaching the observer. The rings are not
symmetrical due to the spin of the black hole and the Doppler shift of
the hot spot.
Einstein rings
- For a near-maximal spin of a/M=0.99, the photons can only escape
the black hole in a prograde orbit. These photons reach the observer
from the right side of the black hole. The inclination is 90 degrees.
Near-maximal spin
- A possible model for the low-frequency QPOs from Kerr black holes
is the Lense-Thirring precession of a hot spot ring of emission that
is inclined relative to the equatorial plane. Such a ring will produce
both modulated light curves and will also produce a modulated iron K
line as different regions of the ring are beamed towards (or away
from) the observer.
i=70 deg, a/M=0.5
i=90 deg, a/M=0.5
Hot Spot QPO Sounds
- These .wav files were created using Ed Bertschinger's application
"sound_XRB". They represent the X-ray light curves of hot spots
orbiting a black hole of mass 10 M_sun, where the ISCO orbital
frequency is in the range 200-500 Hz, depending on the BH's spin.
- A circular hot spot orbit with inclination 30 degrees gives a
steady, sinusoidal light curve with a single tone at ~300 Hz for
a/M=0.5.
i=30 deg
- Increasing the inclination increases the light curve amplitude
(sound volume) and introduces higher harmonic tones as the
relativistic beaming produces a non-sinusoidal light curve.
i=70 deg
- Non-circular orbits have more undertones as the fundamental
orbital frequency forms beat modes with the radial epicyclic frequency
at ~100 Hz.
i=70 deg, e=0.1
- Hot spots that are inclined with respect to the black hole
equatorial plane will experience Lense-Thirring precession, modulating
the light curve at a lower frequency of 10-20 Hz.
i=70 deg, e=0.1, non-planar orbit
- We have also investigated the light curves produced by multiple
hot spots that are continually formed and destroyed with random
phases, producing Quasi-periodic Oscillations. The two cases given
here are the two different models used in Maccarone & Schnittman
(2005).
**Warning: the quasi-periodic nature of these light curves
produces an atonal sound, which can be quite annoying to those with
sensitive hearing**
Case 1 (short hot spot lifetime, all formed
at the same radius)
Case 2 (long hot spot lifetime, formed over
a range of orbital radii)