Principal Investigators: Gerhard Schäfer

*
Project B4 aims to provide accurate and efficient description
for various aspects involved in the dynamics of compact binaries of
arbitrary mass ratio, invoking post-Newtonian (PN) framework to solve
two-body problem in general relativity.
It includes the development of gravitational wave templates for
compact binaries.
*

The current investigations developed accurate and efficient
gravitational wave templates for compact binaries of
arbitrary mass ratio moving in inspiralling eccentric orbits.
These templates will be useful to do `astrophysics' with
planned and proposed space-based gravitational wave detectors
like LISA, BBO and DECIGO. A plethora of recent astrophysically
motivated investigations indicate that compact binaries in inspiralling
eccentric orbits will also be plausible sources of gravitational
radiation for ground-based gravitational wave interferometers.

Further, certain aspects of the
dynamics of compact binaries, where objects were not treated to be
point masses, and associated gravitational wave polarizations
were also obtained.

One of the key ingredients to construct the above mentioned templates is our derivation of post-Newtonian accurate Keplerian-type parametric solution to the conservative dynamics of compact binaries. There are few additional applications for such Keplerian-type parametric solutions and we investigated two such applications. Using our PN accurate Keplerian-type parametric solution, we formally demonstrated the erroneousness of the claim, made in the literature, that dynamics of spinning compact binaries will be chaotic, when spin effects are restricted to the leading order spin-orbit interactions. It is interesting to note that if the above dynamics is chaotic, it will make almost impossible gravitational wave detection from spinning compact binaries. We employed our Keplerian-type parametrization to obtain, for the first time, a parametric derivation of the observable relativistic periastron advance for binary pulsars. Recall that the highly accurate `timing' of double pulsar PSR J0737-3039 eventually allow, via the measurement of PN accurate relativistic periastron advance, the determination of the moment-of-inertia of a neutron star, enabling one to probe the equation of state of highly condensed matter.

In the near future, under Project B4, we plan to undertake investigations that should provide highly accurate and efficient templates for gravitational wave signals emitted by spinning compact binaries, consisting of black holes as well as neutron stars of arbitrary mass ratio, moving in inspiralling eccentric orbits. N-body simulations are required to study realistically the dynamics of collisional star clusters that may create intermediate mass black hole binaries and the dynamics of supermassive black hole binaries resulting from the merger of galaxies. It is important to incorporate general relativistic effects in to these simulations and we will investigate the associated conceptual and computational issues.

We plan to pursue PN accurate computations that will be required to analyze the ultra-sensitive observations of pulsars, especially in binaries, with the proposed Square Kilometre Array.

Former Associates | |||

Michael Brügmann | PhD Student, 2004-2006 | ||

Thibault Damour | Advisor, 2003-2010 | ||

Achamveedu Gopakumar | Postdoc, 2003-2008 | ||

Frieder Gerstner | Student, 2008 | ||

Maria Haney | Student, 2004-2008 | ||

Dörte Hansen | PhD Student, 2003-2008 | ||

Johannes Hartung | PhD Student, 2009-2010 | ||

Steven Hergt | PhD Student, 2006 | ||

Christian Königsdörffer | PdD Student, 2003 | ||

Michael Kramer | Advisor, 2007-2010 | ||

Raoul-Martin Memmesheimer | Student, 2003-2004 | ||

Ira Nörenberg | Student, 2008 | ||

Gerhard Schäfer | Professor, PI 2003-2010 | ||

Sebastian Riese | Student, 2008 | ||

Christian Sohr | Student, 2008 | ||

Rainer Spurzem | Advisor, 2007-2010 | ||

Jan Steinhoff | PhD Student, 2007 | ||

Manuel Tessmer | PhD Student, 2005-2010 | ||

Rico Wachs | Student, 2005 |

[1]
*Full-analytic frequency-domain gravitational wave forms from eccentric compact binaries to 2PN accuracy*

Manuel Tessmer, Gerhard Schäfer,
Ann. Phys. (Berlin) 523:813 (2011)

[2]
*Multipolar equations of motion for extended test bodies in general relativity*

Jan Steinhoff, Dirk Puetzfeld,
Phys. Rev. D 81:044019 (2010)

[3]
*Measuring the spin of the primary black hole in OJ287*

M. Valtonen, S. Mikkola, D. Merritt, A. Gopakumar, H. J. Lehto, T. Hyvönen, H. Rampadarath, R. Saunders, M. Basta, R. Hudec,
Astrophys. J. 709:725, (2010)

[4]
*Reduced Hamiltonian for next-to-leading order spin-squared dynamics of general compact binaries*

Steven Hergt, Jan Steinhoff, Gerhard Schäfer,
Class. Quantum Grav. 27:135007, (2010)

[5]
*Circular Inspiral Templates*

Manuel Tessmer,
to be published in Proceedings of the 12th Marcel Grossmann Meeting on General Relativity, edited by T. Damour, R.T. Jantzen and R. Ruffini, World Scientific, Singapore, (2010)

[6]
*Motion and gravitational wave forms of eccentric compact binaries with orbital-angular-momentum-aligned spins under next-to-leading order in spin-orbit and leading-order in spin(1)-spin(2) and spin-squared coupling*

Manuel Tessmer, Johannes Hartung, Gerhard Schäfer,
Class. Quantum Grav. 27:165005, (2010)

[7]
*Full-analytic frequency-domain first-post-Newtonian-accurate gravitational wave forms from eccentric compact binaries*

Manuel Tessmer, Gerhard Schäfer,
Phys. Rev. D 82: 124064, (2010)

[8]
*Ruling out Kozai resonance in highly eccentric galactic binary millisecond pulsar PSR J1903+0327*

Achamveedu Gopakumar, Manjari Bagchi, Alak Ray,
Mon. Not. Roy. Astron. Soc. 399:L123-L127, (2009)

[9]
*Gravitational waveforms from unequal-mass binaries with arbitrary spins under leading order spin-orbit coupling*

Manuel Tessmer,
Phys. Rev. D 80:124034, (2009)

[10]
*Comparison between numerical-relativity and post-Newtonian waveforms from spinning binaries: the orbital hang-up case*

Mark Hannam, Sascha Husa, Bernd Brügmann, Achamveedu Gopakumar,
Phys. Rev. D 78:104007, (2008)

[11]
*Comparison between numerical relativity and a new class of post-Newtonian gravitational-wave phase evolutions: the non-spinning equal-mass case*

Achamveedu Gopakumar, Mark Hannam, Sascha Husa, Bernd Brügmann,
Phys. Rev. D 78:064026 (2008)

[12]
*Effective one body approach to the dynamics of two spinning black holes with next-to-leading order spin-orbit coupling*

Thibault Damour, Piotr Jaranowski, Gerhard Schäfer,
Phys. Rev. D 78:024009 (2008)

[13]
*Gravitational waves from compact binaries inspiralling along post-Newtonian accurate eccentric orbits: Data analysis implications*

Manuel Tessmer, Achamveedu Gopakumar,
Phys. Rev. D 78:084029, (2008)

[14]
*Next to leading order gravitational wave emission and dynamical evolution of compact binary systems with spin*

Dörte Hansen,
Class. Quant. Grav. 25:165011, (2008)

[15]
*Accurate and efficient gravitational waveforms for certain galactic compact binaries*

Manuel Tessmer, Achamveedu Gopakumar,
Mon. Not. Roy. Astron. Soc. 374:721-728, (2007)

[16]
*Parameteric derivation of the observable relativistic periastron advance for binary pulsars*

C. Koenigsdoerffer and A. Gopakumar,
Phys. Rev. D 73, 044011 (2006)

[17]
*Dynamical evolution and leading order gravitational wave emission of Riemann-S binaries*

D. Hansen,
General Relativity and Gravitation 38 1173 (2006)

[18]
*Phasing of gravitational waves from inspiralling eccentric binaries at the third-and-a-half post-Newtonian order*

C. Koenigsdoerffer and A. Gopakumar,
Phys. Rev. D73 (2006) 124012

[19]
*Post-Newtonian accurate parametric solution to the dynamics of spinning compact binaries in eccentric orbits: The leading order spin-orbit interaction*

C. Koenigsdoerffer and A. Gopakumar,
Phys. Rev. D71, 024039 (2005)

[20]
*Motion and gravitational radiation of a binary system consisting of an oscillating and rotating coplanar dusty disk and a point-like object*

D. Hansen,
General Relativity and Gravitation 37, 1781 (2005)

[21]
*The deterministic nature of conservative post-Newtonian accurate dynamics of compact binaries with leading order spin-orbit interaction*

A. Gopakumar and C. Koenigsdoerffer,
Phys. Rev. D 72 (Rapid Communications), 121501 (2005)

[22]
*Phasing of gravitational waves from inspiralling eccentric binaries*

T. Damour, A. Gopakumar, and B.Iyer,
in the proceedings of the 5th LISA Symposium, Class. Quant. Grav. 22 S381 (2005)

[23]
*Phasing of gravitational waves from inspiralling eccentric binaries*

T. Damour, A. Gopakumar and B. Iyer,
Phys. Rev. D 70, 064028 (2004)

[24]
*Third post-Newtonian accurate generalized quasi-Keplerian parameterization for compact binaries in eccentric orbits*

R.-M. Memmesheimer, A. Gopakumar and G. Schaefer,
Phys. Rev. D 70, 104011 (2004)

[25]
*Binary black-hole dynamics at the third-and-a-half post-Newtonian order in the ADM formalism*

C. Koenigskoerffer, G. Faye and G. Schaefer,
Phys. Rev. D 68, 044004 (2003)

[26]
*Post-Newtonian dynamics and gravitational-wave phasing of compact binary systems*

Christian Königsdörffer,
Ph.D thesis (2006)

[27]
*Computationally efficient gravitational waveforms for certain galactic compact binaries with arbitrary mass ratio in eccentric orbits*

Manuel Tessmer,
Diploma thesis (2006)

[28]
*Semi-analytische Berechnung der Gravitationswellenform eines Binärsystems mit quadrupolartiger Komponente*

Rico Wachs,
Diploma thesis (2007)

[29]
*Dynamik und Gravitationsstrahlung einspiralender Binärsysteme nicht-punktförmiger Objekte*

Dörte Hansen,
Ph.D thesis (2008)

[30]
*Gravitationswellenformen ausgewählter Doppelsternsysteme*

Maria Haney,
Diploma thesis (2009)

[31]
*Bewegung rotierender Körper unter gravitativer Spin-Bahn-Kopplung*

Sebastian Riese,
Diploma thesis (2009)

[32]
*Chaos in gravitativ-gebundenen Binärsystemen mit Spin*

Christian Sohr,
Diploma thesis (2009)

[33]
*Anwendungen von Spin-Hamilton-Funktionen höherer Ordnung in der Gravitationstheorie*

Frieder Gerstner,
Diploma thesis (2009)