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On extreme transient events from rotating black holes and their gravitational wave emission
van Putten, Maurice H. P. M.,Della Valle, Massimo Oxford University Press 2017 Monthly notices of the Royal Astronomical Society Vol.464 No.3
<P>The super-luminous object ASASSN-15lh (SN2015L) is an extreme event with a total energy E-rad similar or equal to 1.1 x 1052 erg in blackbody radiation on par with its kinetic energy E-k in ejecta and a late time plateau in the UV, which defies a nuclear origin. It likely presents a new explosion mechanism for hydrogen-deprived supernovae. With no radio emission and no H-rich environment, we propose to identify Erad with dissipation of a baryon-poor outflow in the optically thick remnant stellar envelope produced by a central engine. By negligible time-scales of light crossing and radiative cooling of the envelope, SN2015L's light curve closely tracks the evolution of this engine. We here model its light curve by the evolution of black hole spin during angular momentum loss in Alven waves to matter at the Inner Most Stable Circular Orbit (ISCO). The duration is determined by sigma = M-T/M of the torus mass M-T around the black hole of mass M: sigma similar to 10(-7) and sigma similar to 10(-2) for SN2015L and, respectively, a long GRB. The observed electromagnetic radiation herein represents a minor output of the rotational energy Erot of the black hole, while most is radiated unseen in gravitational radiation. This model explains the high-mass slow-spin binary progenitor of GWB150914, as the remnant of two CC-SNe in an intra-day binary of two massive stars. This model rigorously predicts a change in magnitude Delta m similar or equal to 1.15 in the light curve post-peak, in agreement with the light curve of SN2015L with no fine-tuning.</P>
van Putten, Maurice H.P.M.,Gwak, B.,Kang, G.,Kim, C.,Kim, H.-C.,Lee, C.-H.,Lee, J.,Lee, S.,Lee, W. EDP Sciences 2018 The European Physical Journal Conferences Vol.168 No.-
<P>The <I>H</I>0-tension problem poses a confrontation of dark energy driving latetime cosmological expansion measured by the Hubble parameter<I> H</I>(<I>z</I>) over an extended range of redshifts <I>z</I>. Distinct values <I>H</I>0 ≃ 73 km s<SUP>-1</SUP> Mpcs<SUP>-1</SUP> and <I>H</I>0 ≃ 68 km s<SUP>-1</SUP> Mpcs<SUP>-1</SUP> obtain from surveys of the Local Universe and, respectively, ΛCBM analysis of the CMB. These are representative of accelerated expansion with <I>H</I>′(0) ≃ 0 by [see formula in PDF] and, respectively, <I>H</I>′(0) > 0 in ΛCDM, where [see formula in PDF] is a fundamental frequency of the cosmological horizon in a Friedmann-Robertson-Walker universe with deceleration parameter <I>q</I>(<I>z</I>) = -1 + (1+z)<I>H</I><SUP>-1</SUP><I>H</I>′(z). Explicit solution <I>H</I>(z) = <I>H</I>0 [see formula in PDF] and, respectively, <I>H</I>(z) = <I>H</I>0[see formula in PDF] are here compared with recent data on <I>H</I>(<I>z</I>) over 0 ≲ z ≲ 2.The first is found to be free of tension with H0 from local surveys, while the latter is disfavored at 2:7σ A further confrontation obtains in galaxy dynamics by a finite sensitivity of inertia to background cosmology in weak gravity, putting an upper bound of <I>m</I> ≲ 10<SUP>-30</SUP> eV on the mass of dark matter. A <I>C</I><SUP>0</SUP> onset to weak gravity at the de Sitter scale of acceleration <I>adS</I> = <I>cH</I>(<I>z</I>), where <I>c</I> denotes the velocity of light, can be seen in galaxy rotation curves covering 0 ≲ <I>z</I> ≲ 2 Weak gravity in galaxy dynamics hereby provides a proxy for cosmological evolution.</P>
van Putten, M. H. P. M.,Della Valle, M.,Levinson, A. EDP Sciences 2011 Astronomy and astrophysics Vol.535 No.-
<P>Context. Some core-collapse supernovae appear to be hyper-energetic, and a subset of these are aspherical and associated with long GRBs. Aims. 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. Methods. We review these events based on a finite efficiency for the conversion of spin energy to magnetic winds powering supernovae. Results. 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.</P>
Detecting rotating black holes in GRB-SNe by LIGO and VIRGO
Maurice H.P.M. van Putten 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.1
GRB030329/SN2003dh demonstrated that Type Ib/c supernovae are the parent population of long GRBs. GRB-supernovae are predicted to produce two bursts in gravitational radiation: in the nucleation of a black hole in core-collapse of a massive progenitor star and subsequently, in spin-down of a black hole in a state of suspended accretion. The black hole-luminosity LH ' 4:410518=30:03 powers a long-duration burst in gravitational radiation, and a radiatively driven supernova closely related to that of Bethe, Brown and Lee (2003). Here, = T = H and = MT =MH denote the relative angular velocity and mass of the torus to that of the black hole. These emissions are of interest to the newly commissioned ground based detectors LIGO and VIRGO. Detection of the long-burst provides a method for identifying Kerr black holes as objects in the universe.
A NEW ESTIMATOR OF THE DECELERATION PARAMETER FROM GALAXY ROTATION CURVES
American Astronomical Society 2016 The Astrophysical journal Vol.824 No.1
<P>The nature of dark energy can be probed by the derivative Q = dq(z)/dz vertical bar(0) at redshift z = 0 of the deceleration parameter q(z). It is probably static if Q < 1 or dynamic if Q > 2.5, supporting Lambda CDM or Lambda =(1 - q)H-2, respectively, where H denotes the Hubble parameter. We derive q = 1 - (4 pi a(0)/cH)(2), enabling a determination of q(z) by measuring Milgrom's parameter, a(0)(z), in galaxy rotation curves, equivalent to the coefficient A in the Tully-Fisher relation V-c(4) = AM(b) between a rotation velocity V-c and a baryonic mass M-b. We infer that dark matter should be extremely light, with clustering limited to the size of galaxy clusters. The associated transition radius to non-Newtonian gravity can conceivably be probed in a freefall Cavendish-type experiment in space.</P>
American Astronomical Society 2016 The Astrophysical journal Vol.819 No.2
<P>Core-collapse supernovae (CC-SNe) are factories of neutron stars and stellar-mass black holes. SNe Ib/c stand out as potentially originating in relatively compact stellar binaries and they have a branching ratio of about 1% into long gamma-ray bursts. The most energetic events probably derive from central engines harboring rapidly rotating black holes, wherein the accretion of fall-back matter down to the innermost stable circular orbit (ISCO) offers a window into broadband extended gravitational wave emission (BEGE). To search for BEGE, we introduce a butterfly filter in time-frequency space by time-sliced matched filtering. To analyze long epochs of data, we propose using coarse-grained searches followed by high-resolution searches on events of interest. We illustrate our proposed coarse-grained search on two weeks of LIGO S6 data prior to SN 2010br (z = 0.002339) using a bank of up to 64,000 templates of one-second duration covering a broad range in chirp frequencies and bandwidth. Correlating events with signal-to-noise ratios > 6 from the LIGO L1 and H1 detectors reduces the total to a few events of interest. Lacking any further properties reflecting a common excitation by broadband gravitational radiation, we disregarded these as spurious. This new pipeline may be used to systematically search for long-duration chirps in nearby CC-SNe from robotic optical transient surveys using embarrassingly parallel computing.</P>