Bulletin of the American Physical Society
APS April Meeting 2010
Volume 55, Number 1
Saturday–Tuesday, February 13–16, 2010; Washington, DC
Session D14: Modeling Black Hole Binaries |
Hide Abstracts |
Sponsoring Units: GGR Chair: Bernard Kelly, NASA Goddard Space Flight Center Room: Washington 4 |
Saturday, February 13, 2010 1:30PM - 1:42PM |
D14.00001: Simulations of Binary Black Hole Mergers in Gaseous Environments Brian Farris, Yuk Tung Liu, Stuart Shapiro Massive black hole mergers in the presence of gaseous accretion flows are prime candidates for simultaneous observations of both gravitational waves and electromagnetic signals. We study such systems using our fully general relativistic hydrodynamics code, focusing on the characterization of potentially observable electromagnetic signatures. We outline preliminary results from our investigations, focusing on binaries which merge inside a large, adiabatic cloud with constant gas density and temperature at infinity. We consider cases in which the binary center of mass is at rest (the ``BHBH Bondi accretion problem'') or moving (the ``BHBH Bondi-Hoyle-Lyttleton accretion problem'') relative to the gas cloud. We find evidence for enhancements in the electromagnetic luminosity over the values for single, isolated BHs. Such enhancements may constitute an observable signal. [Preview Abstract] |
Saturday, February 13, 2010 1:42PM - 1:54PM |
D14.00002: Binary Black Hole Mergers in a Gas Cloud and their Electromagnetic Signatures Tanja Bode, Roland Haas, Tamara Bogdanovic, Pablo Laguna, Deirdre Shoemaker Coincident detections of electromagnetic (EM) and gravitational wave (GW) signatures from individual supermassive black hole (SMBH) binary mergers are the next observational grand challenge. Such coincident detections would identify the location of the event to higher accuracy as well as provide a means to study cosmological evolution, accretion processes associated with SMBH binaries, and more generally to tests of underlying principles of general relativity. Understanding conditions under which coinciding EM and GW signatures are expected to arise during coalescence is therefore of paramount importance. As an essential step towards this goal, we present results from the first fully general relativistic, hydrodynamical study of the late inspiral and merger of equal-mass SMBHs with spin $a/M_h \le 0.6$ in a gas cloud. [Preview Abstract] |
Saturday, February 13, 2010 1:54PM - 2:06PM |
D14.00003: Binary black hole initial data with tidal deformations and outgoing radiation Nathan Johnson-McDaniel, Nicolas Yunes, Wolfgang Tichy, Benjamin Owen We present initial data for the quasicircular inspiral of a nonspinning black hole binary, including tidal deformations and outgoing radiation. We construct these data by asymptotically matching two perturbed Schwarzschild metrics to a post-Newtonian (PN) metric. We carry out this matching through $O(v^4)$ ($v$ is the binary's orbital velocity) so the data are conformally curved. The PN metric includes both near and radiation zone contributions and uses the 3.5PN results for the binary's past history. Asymptotic matching produces piecewise continuous global data; we smooth the joins using transition functions. The inclusion of tidal deformations and outgoing radiation might ameliorate the initial burst of spurious radiation observed with conformally flat data. Such an improvement might be essential for simulations to provide sufficiently accurate templates for parameter estimation with advanced gravitational wave detectors. [Preview Abstract] |
Saturday, February 13, 2010 2:06PM - 2:18PM |
D14.00004: Numerical simulations of binary black holes with nearly extremal spins Geoffrey Lovelace There is a significant possibility that astrophysically realistic black holes may have nearly extremal spins (i.e., spins close to 1 in dimensionless units). The prospect of observing the gravitational waves from a binary-black-hole merger with nearly extremal spins motivates the goal of simulating these systems numerically. These simulations must begin with initial data that satisfy the Einstein constraint equations; however, the commonly used methods of generating constraint-satisfying initial data cannot yield data with nearly extremal spins. In this talk, I will describe evolutions of conformally curved binary-black-hole initial data with nearly extremal spins using the Caltech-Cornell-CITA Spectral Einstein Code (SpEC). [Preview Abstract] |
Saturday, February 13, 2010 2:18PM - 2:30PM |
D14.00005: Extracting physics from numerical spacetimes with constant-expansion surfaces Eloisa Bentivegna, Erik Schnetter, Badri Krishnan Extracting unambiguous physical information from a spacetime has long been one of the central issues in General Relativity. Defining unique expressions that are generally covariant and have recognizable physical properties (e.g., obey conservation laws when the appropriate symmetries apply) has proven to be impossible without the introduction of further structure, such as coordinate conditions at null infinity or restrictions on the 2-surfaces to be used for gravitational wave extraction. Inspired by the successes of the Isolated and Dynamical Horizon framework, along with its practical effectiveness in numerical contexts, we discuss the use of general constant-expansion surfaces in the resolution of the ambiguities, and illustrate the results in a few cases of physical interest. [Preview Abstract] |
Saturday, February 13, 2010 2:30PM - 2:42PM |
D14.00006: Comparing binary black hole evolutions using finite difference and spectral methods Enrique Pazos, Larry Kidder, Abdul Mroue, Manuel Tiglio We compare waveforms for binary black hole simulations using finite difference with adaptive mesh refinement and spectral methods with multiple domains. In both cases we use the exact same initial data, extracting waves at a fixed location and extrapolating them to infinity. [Preview Abstract] |
Saturday, February 13, 2010 2:42PM - 2:54PM |
D14.00007: Binary Black Hole Mergers in SpEC Bela Szilagyi The Caltech-Cornell spectral Einstein Code (SpEC) is now able to robustly and accurately evolve binary black hole systems through the inspiral, merger and ringdown phases. This is attributed to new gauge conditions as well as a robustly stable numerical algorithm. The talk will highlight the key new elements of our algorithm. [Preview Abstract] |
Saturday, February 13, 2010 2:54PM - 3:06PM |
D14.00008: Modelling multiple modes of spinning merger waveforms Bernard Kelly, John Baker, William D. Boggs, James van Meter The Implicit Rotating Source (IRS) ansatz provides a coherent model of the dominant modes of gravitational radiation from a merging black-hole binary. Building on work with unequal-mass nonspinning binaries [Baker et al. Phys. Rev. D vol. 78, 044046 (2008)], we have applied the IRS to mergers of aligned and anti- aligned spinning binaries to form useful multi-mode waveform templates. We also discuss issues of parameter selection and spin and mass measurement with the Goddard Hahndol code. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700