LIGO Seminar

Series: LIGO Seminar Series

A new paradigm for binary black-hole spin precession

Michael Kesden, Professor, Department of Physics, UTDallas,

Binary black holes evolve on three distinct timescales: the short orbital

time given by Kepler's 3rd law, the intermediate precession time on which

the black-hole spins and orbital angular momentum change direction, and the

longer radiation-reaction time on which the binary separation decreases due

to gravitational-wave-emission. We show that on intermediate timescales

where the orbital motion can be averaged and the energy and total angular

momentum can be held fixed, spin precession is quasi-periodic: the two spins

and orbital angular momentum return to their initial relative orientation

after a precessional period τ during which all three vectors precess by an

angle α about the total angular momentum. This precession can be

categorized into three distinct precessional morphologies depending on the

values of constants conserved on the precession timescale. We further show

that LIGO has the sensitivity to distinguish the gravitational waves emitted

by black holes in these three morphologies, and that in doing so it can

discover important clues about the astrophysical black-hole formation.

We plan to broadcast these talks using TeamSpeak. Use a sub-channel of

LIGO Lab called "LIGO Seminar", which is not password protected.

NOTE: These and all other scheduled LIGO seminars are listed on the LIGO

Laboratory seminar calendar for convenient reference:

http://arcturus.ligo.caltech.edu/cgi-bin/calendar/Calcium40.pl?Op=

ShowIt&CalendarName=LIGO_Seminars

OR on LIGO Website: Click on LIGO CIT, under Calendars, see LIGO Seminar

Event Sponsors:

For more information, please contact Sydney Meshkov by email at [email protected].