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The most energetic GRB-supernovae probably derive from rotating stellar mass black holes. Based on BeppoSax data, we identify a mechanism for exploding a remnant stellar envelope by disk winds. A specific signature is high frequency modulations in the accompanying prompt GRB emission from dissipation in high energy emissions along the black hole spin axis due, in part, to forced turbulence in the inner disk or torus mediated by frame dragging. A majority of long GRBs are found to have significant autocorrelation below 10 Hz with chirps extending up to 1000 Hz. Their comoving Fourier spectra satisfy a power law with index $\alpha\simeq-0.82$ up to about one hundred Hz and comoving chirp spectra show broken power laws with $\alpha\simeq-0.65$ up to 10 Hz, $\alpha\simeq-0.25$ up to a few hundred Hz and $\alpha\simeq0$ beyond. These high frequency signatures are the most direct signature of long-lived turbulence down to the ISCO of rotating black holes, pointing directly accompanying long duration bursts in gravitational wave emission., Comment: 4 figures

We report on evidence for black hole spindown in the light curves of the BATSE catalogue of 1491 long GRBs by application of matched filtering. This observation points to a strong interaction of the black hole with surrounding high density matter at the ISCO, inducing non-axisymmetric instabilities sustained by cooling in gravitational wave emission. Opportunities for LIGO-Virgo and the recently funded KAGRA experiments are highlighted, for long GRBs with and without supernovae and for hyper-energetic core-collapse supernovae within a distance of about 35 Mpc in the Local Universe., Comment: Invited talk at Vulcano 2012, Italy, accepted for publication in Acta Polytechnica

A budget neutral strategy is proposed for NSF to lead the implementation of multimessenger astronomy and astrophysics, as outlined in the Astro2010 Decadal Survey. The emerging capabilities for simultaneous measurements of physical and astronomical data through the different windows of electromagnetic, hadronic and gravitational radiation processes call for a vigorous pursuit of new synergies. The proposed approach is aimed at the formation of new collaborations and multimessenger data-analysis, to transcend the scientific inquiries made within a single window of observations. In view of budgetary constraints, we propose to include the multimessenger dimension in the ranking of proposals submitted under existing NSF programs., Comment: Submitted as input to the NSF/AST Portfolio Review (2011/11/17)

The BATSE catalogue is searched for evidence of spindown of black holes or proto-neutron stars (PNS) by extracting normalized light curves (nLC). The nLC are obtained by matched filtering, to suppress intermediate time scales such as due to the shock break-out of GRB jets through a remnant stellar envelope. We find consistency within a few percent of the nLC and the model template for spindown of an initially extremal black hole against high-density matter at the ISCO. The large BATSE size enables a study of the nLC as a function of durations $T_{90}$. The resulting $\chi^2_{red}$ is within a $2.35\sigma$ confidence interval for durations $T_{90}>20$ s, which compares favorably with the alternative of spindown against matter further out and spindown of a PNS, whose $\chi^2$ fits are, respectively, outside the 4$\sigma$ and 12$\sigma$ confidence intervals. We attribute spindown against matter at the ISCO to cooling by gravitational-wave emission from non-axisymmetric instabilities in the inner disk or torus as the result of a Hopf bifurcation in response to energetic input from the central black hole. This identification gives an attractive outlook for chirps in quasi-periodic gravitational waves lasting tens of seconds of interest to LIGO, Virgo and the LCGT., Comment: 27 pages, 10 figures, to appear in Progress of Theoretical Physics

We give an exact solution for the static force between two black holes at the turning points in their binary motion. The results are derived by Gibbs' principle and the Bekenstein-Hawking entropy applied to the apparent horizon surfaces in time-symmetric initial data. New power laws are derived for the entropy jump in mergers, while Newton's law is shown to derive from a new adiabatic variational principle for the Hilbert action in the presence of apparent horizon surfaces. In this approach, entropy is strictly monotonic such that gravity is attractive for all separations including mergers, and the Bekenstein entropy bound is satisfied also at arbitrarily large separations, where gravity reduces to Newton's law. The latter is generalized to point particles in the Newtonian limit by application of Gibbs' principle to world-lines crossing light cones., Comment: Accepted for publication in Phys. Rev. D

Evaporative evolution of stellar clusters is shown to be relaxation limited when the number of stars satisfies $N>>N_c$, where $N_c\simeq 1600$. For a Maxwell velocity distribution that extends beyond the escape velocity, this process is {\em bright} in that the Kelvin-Helmholtz time scale, $f_H^{-1}t_{relax}$, is shorter than the Ambartsumian-Spitzer time scale, $f_N^{-1}t_{relax}$, where $f_H>f_N$ denote the fractional changes in total energy and number of stars per relaxation time, $t_{relax}$. The resulting evaporative lifetime $t_{ev}\simeq 20.5 t_{relax}$ for isolated clusters is consistent with Fokker-Planck and N-body simulations, where $t_{relax}$ is expressed in terms of the half-mass radius. We calculate the grey body factor by averaging over the anisotropic perturbation of the potential barrier across the tidal sphere, and derive the tidal sensitivity ${d\ln t_{ev}}/{dy}\simeq -1.9$ to -0.7 as a function of the ratio $y$ of the virial-to-tidal radius. Relaxation limited evaporation applies to the majority of globular clusters of the Milky Way with $N=10^4-10^6$ that are in a pre-collapse phase. It drives streams of stars into the tidal field with a mean kinetic energy of 0.71 relative to temperature of the cluster. Their $S$ shape morphology leads in sub-orbital and a trails in super-orbital streams separated by $3.4\sigma/\Omega$ in the radial direction of the orbit, where $\Omega$ denotes the orbital angular velocity and $\sigma$ the stellar velocity dispersion in the cluster. These correlations may be tested by advanced wide field photometry and spectroscopy., Comment: NewA, online 13 November 2011

Some core-collapse supernovae appear to be hyper-energetic, and a subset of these are aspherical and associated with long GRBs. We use observations of electromagnetic emission from core-collapse supernovae and GRBs to impose constraints on their free energy source as a prior to searches for their gravitational wave emission. We review these events based on a finite efficiency for the conversion of spin energy to magnetic winds powering supernovae. We find that some of the hyper-energetic events cannot be powered by the spindown of rapidly rotating proto-neutron stars by virtue of their limited rotational energy. They can, instead, be produced by the spindown of black holes providing a distinct prospect for gravitational-wave emission of interest to LIGO, Virgo, and the LCGT., Comment: A&A Lett., to appear

In the OPERA experiment, the time of arrival of the neutrino light curve at LNGS is defined by a best-fit to the generating proton PDF at CERN. By a two parameter matched filtering procedure, we determine that the OPERA neutrino light curve is narrower by about 0.4-0.5% relative to the proton PDF. The results indicate as yet undetermined physics in the creation of neutrinos in CERN and a reduced significance of the OPERA detection to less than 4 $\sigma.$

Observational evidence for black hole spin down has been found in the normalized light curves of long GRBs in the BATSE catalogue. Over the duration $T_{90}$ of the burst, matter swept up by the central black hole is susceptible to non-axisymmetries producing gravitational radiation with a negative chirp. A time sliced matched filtering method is introduced to capture phase-coherence on intermediate timescales, $\tau$, here tested by injection of templates into experimental strain noise, $h_n(t)$. For TAMA 300, $h_n(f)\simeq 10^{-21}$ Hz$^{-\frac{1}{2}}$ at $f=1$ kHz gives a sensitivity distance for a reasonably accurate extraction of the trajectory in the time frequency domain of about $D\simeq 0.07-0.10$ Mpc for spin fown of black holes of mass $M=10-12M_\odot$ with $\tau=1$ s. Extrapolation to advanced detectors implies $D\simeq 35-50$ Mpc for $h_n(f)\simeq 2\times 10^{-24}$ Hz$^{-\frac{1}{2}}$ around 1 kHz, which will open a new window to rigorous calorimetry on Kerr black holes., Comment: To appear in PRD

Kerr black holes are energetically similar to spinning tops accompanied by frame dragging in the surrounding spacetime. Frame dragging is shown herein to be a universal causal agent for producing multi-messenger emissions. We discuss high energy emissions produced by gravitational spin-orbit coupling along the axis of rotation and low energy emissions from surrounding matter via a torus magnetosphere. Model results point to ultra-high energy cosmic rays (UHECRs) from supermassive black holes at about the Greisen-Zatsepin-Kuzmin (GZK) energy threshold from low-luminosity active galactic nuclei (AGN), and to high-energy photon emissions from stellar mass black holes in ultra-relativistic capillary jets. The former compares favorably with recent results by the Pierre Auger Observatory (PAO). The latter compares favorably with gamma-ray burst data from the High Energy Transient Exporer (HETE) II, {\em Swift} and the Burst and Transient Source Experiment (BATSE), wherein a finite lifetime of black hole spin is found to improve the correlation between peak energies and true energies in gamma-rays. Matched filtering applied to 600 light curves of long GRBs identifies a process of viscous spin down against matter at the inner most stable circular orbit. We conclude that long GRBs are spin powered, not accretion powered, from core-collapse supernovae and merger events such as GRB060614. Contemporaneous low energy emissions are expected from surrounding matter in gravitational waves by a pressure driven Papaloizou-Pringle instability, and more so than in accompanying MeV-neutrinos and magnetic winds. The latter powers aspherical radio-loud supernovae in collapsars and long duration extragalactic radio bursts from GRB060614 type events. This outlook is of interest to emerging multi-messenger surveys., Comment: Invited review, in Orleans School On The Sciences Of The Universe: Mass Motion (Springer-Verlag), revised following editorial comments, to appear

Rotating black holes can power the most extreme non-thermal transient sources. They have a long-duration viscous time-scale of spin-down and produce non-thermal emissions along their spin-axis, powered by a relativistic capillary effect. We report on the discovery of exponential decay in BATSE light curves of long GRBs by matched filtering, consistent with a viscous time-scale, and identify UHECRs energies about the GZK threshold in linear acceleration of ion contaminants along the black hole spin-axis, consistent with black hole masses and lifetimes of FR II AGN. We explain the absence of UHECRs from BL Lac objects due to UHECR emissions preferably at appreciable angles away from the black hole spin-axis. Black hole spin may be key to unification of GRBs and their host environments, and to AGN and their host galaxies. Our model points to long duration bursts in radio from long GRBs without supernovae and gravitational-waves from all long GRBs., Comment: Accepted by MNRAS

Gravitational spin-orbit interactions induce a relativistic capillary effect along open magnetic flux-tubes, that join the event horizon of a spinning black hole to infinity. It launches a leptonic outflow from electron-positron pairs created near the black hole, which terminates in an ultra-relativistic Alfv\'en wave. Upstream to infinity, it maintains a clean linear accelerator for baryons picked-up from an ionized ambient environment. We apply it to the origin of UHECRs and to spectral energy correlations in cosmological gamma-ray bursts. The former is identified with the Fermi-level of the black hole event horizon, the latter with a correlation $E_pT_{90}^{1/2}\simeq E_\gamma$ in HETE-II and Swift data., Comment: 1 figure

Although there is strong support for the collapsar engine as the power source of long-duration gamma-ray bursts (GRBs), we still do not definitively know the progenitor of these explosions. Here we review the current set of progenitor scenarios for long-duration GRBs and the observational constraints on these scenarios. Examining these models, we find that single stars cannot be the only progenitor for long-duration GRBs. Several binary progenitors can match the solid observational constraints and also have the potential to match the trends that we are currently seeing in the observations. Type Ib/c supernovae are also likely to be produced primarily in binaries; we discuss the relationship between the progenitors of these explosions and those of the long-duration GRBs.

Binary black hole coalescence produces a finite burst of gravitational radiation which propagates towards quiescent infinity. These spacetimes are analytic about infinity and contain a dimensionless coupling constant $M/s$, where $M$ denotes the total mass-energy and $s$ an imaginary distance. This introduces globally convergent Fourier series on a complex radial coordinate, allowing spectral representation of black hole spacetimes in all three dimensions. We illustrate this representation theory on a Fourier-Legendre expansion of Boyer-Lindquist initial data and a scalar wave equation with signal recovery by Cauchy's integral formula., Comment: Based on an invited talk at the Int'l Conf. Theor. Physics, 11-16 April 2005, Lebedev Physical Institute, Moscow

The discovery of the GRB-supernova association poses the question on the nature of the inner engine as the outcome of Type Ib/c supernovae. These events are believed to represent core-collapse of massive stars, probably in low-period stellar binaries and similar but not identical to the Type II event SN1987A. The branching ratio of Type Ib/c supernovae into GRB-supernovae has the remarkably small value of less than 0.5%. These observational constraints point towards a rapidly rotating black hole formed at low probability with low kick velocity. The putative black hole hereby remains centered, and matures into a high-mass object with large rotational energy in angular momentum. As the MeV-neutrino emissions from SN1987A demonstrate, the most powerful probe of the inner workings of core-collapse events are radiation channels to which the remnant envelope is optically thin. We here discuss the prospect of gravitational-wave emissions powered by a rapidly rotating central black hole which, in contrast to MeV-neutrinos, can be probed to distances as large as 100Mpc through upcoming gravitational-wave detectors LIGO and Virgo. We identify the GRB-emissions, commonly attributed to ultrarelativistic baryon-poor ejecta, with a new process of linear acceleration of charged particles along the axis of rotation of a black hole in response to spin-orbit coupling. We include some preliminary numerical simulations on internal shocks produced by intermittent ejecta. The results showing a radial splash, which points towards low-luminosity and lower-energy radiation at large angles, possibly related to X-ray flashes., Comment: Invited Contribution to the Proc. GRBs in the Afterglow Era: 4th Workshop, to appear in Il Nuovo Cimento

Current phenomenology suggests the presence of a compact baryon-poor energy source to cosmological gamma-ray bursts reacting to high-density matter. The association of short and long gamma-ray bursts with hyper- and suspended accretion onto slowly and rapidly spinning black holes predicts weak X-ray afterglow emissions from short bursts, as in GRB050509B and GRB050709. Long gamma-ray bursts are probably the birth place of rapidly spinning high-mass black holes in core-collapse of massive stars, as in GRB030329 with supernova SN2003dh. This predicts a long-duration burst of gravitational radiation powered by the spin-energy of the black hole. In contrast to MeV-neutrino emissions, as in SN1987A, this can be tested by the advanced detectors LIGO and Virgo about once per year up to distances of about 100Mpc. Detection of the expected chirps and long-duration bursts of gravitational waves promises identification of Kerr black holes as the most luminous objects in the Universe., Comment: invited contribution to the Kerr Fest 2004, to appear with Cambridge University Press

The gravitational-wave spectrum emitted by a non-axisymmetric torus rotating at an angular velocity $\Omega_T$, is derived in terms of a structure function representing a combination of sausage-tilt modes in the torus in the limit of an incompressible fluid. The analysis of the gravitational-wave spectrum is then applied to a model proposed recently, in which a highly magnetized torus interacts with a stellar mass, Kerr black hole via poloidal field lines that connect the torus and the horizon. The deformation of the torus results from global magnetic instabilities when the magnetic field strength inside the torus exceeds a few times $10^{15}$ Gauss. The dynamics of the system is illustrated using a non-MHD toy model. It is found that, quite generally, most of the gravitational-wave energy emitted is in the frequency range of sensitivity of LIGO and Virgo., Comment: 20 pages, 5 figures

Core-collapse in massive stars is believed to produce a rapidly spinning black hole surrounded by a compact disk or torus. This forms an energetic MeV-nucleus inside a remnant He-core, powered by black hole-spin energy. The output produces a GRB-supernova, while most of the energy released is in gravitational radiation. The intrinsic gravitational-wave spectrum is determined by multipole mass-moments in the torus. Quadrupole gravitational radiation is radiated at about twice the Keplerian frequency of the torus, which is non-axisymmetric when sufficiently slender, representing a ``{\em black hole-blob}" binary system or a "{\em blob-blob}" binary bound to the central black hole. We here discuss line-broadening in the observed spectrum due to Lense-Thirring precession, which modulates the orientation of the torus to the line-of-sight. This spectral feature is long-lived, due to weak damping of precessional motion. These events are believed to occur perhaps once per year within a distance of 100Mpc, which provides a candidate source for Advanced LIGO., Comment: 7 pages, two figures, accepted for publication in PRD

We study centered and decentered nucleation of black holes in core-collapse of massive stars in binaries. By Bekenstein's gravitational-radiation recoil mechanism, a newly nucleated black hole typically leaves the central core prematurely. With low probability, the black hole remains centered and matures to a high-mass black hole which spins rapidly if the binary is compact. GRB030329/SN2003dh demonstrates that Type Ib/c supernovae are the parent population of long GRBs, whose branching ratio is ${\cal R}=(2-4)\times 10^{-3}$. We identify ${\cal R}$ with the low probability of centered nucleation in compact binaries. Decentered events are predicted to produce a single short burst in gravitational radiation. Centered events are predicted to produce a second, long-burst in gravitational radiation powered by a luminous black hole. These signatures are of interest to LIGO, VIRGO and TAMA., Comment: to appear in ApJ Lett

An energy $E=\omega J$ is derived for gravitational spin-orbit coupling by frame-dragging $\omega$ acting on angular momentum $J$. This interaction defines a no-boundary mechanism for linear acceleration of magnetized matter along the axis of rotation of black holes. We explain GRB030329/SN2003dh by centered nucleation of a high-mass black hole with rapid rotation, producing baryon-poor ejecta by gravitational spin-orbit coupling. The duration of the burst is attributed to spin-down in the emission of gravitational-waves by a surrounding non-axisymmetric torus.