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Gravitational Wave Astronomy Riccardo Sturani International Institute of Physics - UFRN - Natal (Brazil) Dark Universe ICTP-SAIFR, Oct 25th, 2019 Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 1 / 29 GW basics in 1 slide Gauged fixed metric perturbations hµν after discarding h0µ components, which are not radiative transverse waves ! h+ h× 0 hij = h× h+ 0 0 − 1 0 0 0 @ 2 pol.A state like any mass-less particle h+ h× Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 2 / 29 LIGO and Virgo: very precise rulers Robert Hurt (Caltech) Light intensity / light travel difference in perpendicular arms Effective optical path increased by factor N ∼ 500 via Fabry-Perot cavities Phase shift ∆φ ∼ 10−8 can be measured ∼ 2πN∆L/λ ! ∆L ∼ 10−15=N m Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 3 / 29 Almost omnidirectional detectors Detectors measure hdet : linear combination F+h+ + F×h× L H -101 F+ F× h+;× depend on source pattern functions F+;× depend on orientation source/detector Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 4 / 29 Almost omnidirectional detectors Detectors measure hdet : linear combination F+h+ + F×h× L V -101 F+ F× h+;× depend on source pattern functions F+;× depend on orientation source/detector Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 4 / 29 2 2 Pattern functions: F+ + F × p Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 5 / 29 The LIGO and Virgo observatories • Observation run O1 Sept '15 - Jan '16 ∼ 130 days, with 49.6 days of actual data, PRX (2016) 4, 041014, 2 detectors,3BBH • O2 Dec. '16 { Jul'17 2 det's + Aug '17 3 det's 3(+4) BBH +1BNS in double(triple) coinc. • O3a:3 detectors, Apr 2nd - Oct 1st 2019 • O3b: Nov 1st { 6 months In ∼ end of 2019 Japanese KAGRA and ∼ 2025 Indian INDIGO will join the collaboration Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 6 / 29 Wave generation: localized sources Einstein formula relates hij to the source quadrupole moment Qij Z 1 Q = d 3xρ x x − δ x 2 ; v 2 ' G M=r ; η ≡ m m =M2 ij i j 3 ij N 1 2 2G d 2Q 2G ηMv 2 h ∼ g(θ ) N ij ' N cos(2φ(t)) ij LN D dt2 D r −3=2 M 1=2 M −1 f = 2kHz < fMax ' 12kHz 30Km 3M 3M f 1=3 M 1=3 1 v = 0:3 < p 1kHz M 6 Geometric factor g(θLN ) takes account of transversality projection (angular momentum L of the binary, observation direction N) 1 + cos2(θ ) Mv 2 h ∼ LN η cos φ(t =M; η; S 2=m4;:::) + 2 D s i i Mv 2 h ∼ cos(θ ) η sin φ(t =M; η; : : :) × LN D s Amplitudes of 2 polarizations modulated by θLN (h % for θLN &0), never both vanishing unlike dipolar motion for the electromagnetic case Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 7 / 29 Wave generation: localized sources Einstein formula relates hij to the source quadrupole moment Qij Z 1 Q = d 3xρ x x − δ x 2 ; v 2 ' G M=r ; η ≡ m m =M2 ij i j 3 ij N 1 2 2G d 2Q 2G ηMv 2 h ∼ g(θ ) N ij ' N cos(2φ(t)) ij LN D dt2 D r −3=2 M 1=2 M −1 f = 2kHz < fMax ' 12kHz 30Km 3M 3M f 1=3 M 1=3 1 v = 0:3 < p 1kHz M 6 Geometric factor g(θLN ) takes account of transversality projection (angular momentum L of the binary, observation direction N) 1 + cos2(θ ) M(1 + z)v 2 h ∼ LN η cos φ(t =(M(1 + z)); η; S 2=m4;:::) + 2 D(1 + z) O i i M(1 + z)v 2 h ∼ cos(θ ) η sin φ(t =(M(1 + z)); η; : : :) × LN D(1 + z) O Amplitudes of 2 polarizations modulated by θLN (h % for θLN &0), never both vanishing unlike dipolar motion for the electromagnetic case Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 7 / 29 Wave generation: localized sources Einstein formula relates hij to the source quadrupole moment Qij Z 1 Q = d 3xρ x x − δ x 2 ; v 2 ' G M=r ; η ≡ m m =M2 ij i j 3 ij N 1 2 2G d 2Q 2G ηMv 2 h ∼ g(θ ) N ij ' N cos(2φ(t)) ij LN D dt2 D r −3=2 M 1=2 M −1 f = 2kHz < fMax ' 12kHz 30Km 3M 3M f 1=3 M 1=3 1 v = 0:3 < p 1kHz M 6 Geometric factor g(θLN ) takes account of transversality projection (angular momentum L of the binary, observation direction N) 2 2 1 + cos (θLN ) Mv 2 4 h+ ∼ η cos φ(tO =M; η; Si =mi ;:::) 2 dL Mv 2 h× ∼ cos(θLN ) η sin φ(tO =M; η; : : :) dL Amplitudes of 2 polarizations modulated by θLN (h % for θLN &0), never both vanishing unlike dipolar motion for the electromagnetic case h sensitive to red-shifted masses M ! M(1 + z) ≡ M Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 7 / 29 Binary systems and compact detected so far Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 8 / 29 https://www.gw-openscience.org/catalog/ Binary black hole events in O1 and O2 1.00 1.0 0.75 0.8 0.50 0.25 See however Princeton's group 0.6 o f r f t s e 0.00 a p results 0.4 0.25 0.50 arXiv:1904.07214 LVC-reported 0.2 0.75 This work Zackay et al. (2019) 1.00 0.0 20 40 60 80 100 source Mtot (M ) Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 9 / 29 Sky localization of GW binary systems detected so far 60° GW170104 60° 60° 60° GW170608 GW170823 GW151012 GW170729 GW151226 30° 30° 30° 30° 0° 0° GW170818 0h 21h 18h 15h 12h 9h GW170104 6h 3h 0h 0h 21h 18h 15h 12h 9h 6h 3h 0h GW170104 GW170809 -30° -30° -30° -30° GW170729 GW170817 GW151012 GW170823 GW150914 -60° GW170814 -60° -60° GW151226 -60° Sky localization regions shrinks when Virgo in: 3rd detector matters! LIGO/Virgo 1811.12907 Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 10 / 29 Astro sources emitting transient GWs/EM/ν radiation 2 Coalescing binary systems of compact objects: η ≡ m1m2=M 5=3 2=3 −2 M fmax ∆EGW ∼ 4 × 10 M η 3M 1 kHz A good proxy of the fmax is the Innermost Stable Circular Orbit frequency 1 1 M −1 fISCO = p ' 2kHz 6 6 M M For NS-NS/BH ejected material supposed to produce short (< 2 sec) GRBs Eγ ∼keV-MeV, ejected sub-relativistic material may produce radio signals TeV-PeV ν @ γ emission ν: baryon loaded jets may emit νs: PeV-EeV ν @ optical afterglow NS-NS/BH ! energetic outflows at different timescale/wavelength Rapid neutron capture in the sub-relativistic ejecta can produce a kilonova or macronova, with optical and near-infrared signal (hours - weeks) Eventually radio blast from sub-relativistic outflow (months to years) LIGO/Virgo + EM partners ApJ Let. 2016 Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 11 / 29 Association with 20 short GRB during O1 (before GW170817) 100 10−1 cumulative distribution BNS exclusion NS-BH exclusion BNS extrapolation NS-BH extrapolation EM observation 10−2 10−2 10−1 100 redshift GW searched in a [-5,+1) sec window with GRB GW constraints far from EM exclusion distance, but extrapolation to design Advanced LIGO sensitivity (2 years of data) will lead to detection/non-trivial constraints LIGO/Virgo Astrophys.J. 841 (2017) no.2, 89 Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 12 / 29 GW170817 GW trigger on Aug 17th, 2017, ended at 12h 41' 04.4" UTC, first in in LIGO Hanford, then confirmed as a triple coincidence ! localized in an area of ∼ 28 deg2 GRB trigger from Fermi-GBM 1.7" after first optical image 10.87 hr afterwards by One-Meter Two Hemisphere team with Swope telescope at Las Campanas Observatory in Chile X obtained by the X-Ray Telescope on Swift after 14.9 h (NuSTAR 16.8 h) radio (∼ 3; 6 GHz) by VLA 16 days after GW event LIGO/Virgo & Partner Astronomy groups, Astrophys.J. 848 (2017) no.2, L12 Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 13 / 29 An example of the optical image Transient Optical Robotic Observatory of the South Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 14 / 29 GW170817 and ν detectors Potential νs down-going for Antares and IceCube, grazing for Auger Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 15 / 29 GW170817 and ν detectors Potential νs down-going for Antares and IceCube, grazing for Auger Source location at optical detection Riccardo Sturani (IIP-UFRN) Gravitational Wave Astronomy DU - Oct 25th, 2019 15 / 29 ANTARES and ICECube look for ν GW170817 Neutrino limits (fluence per flavor: x + x) 103 ±500 sec time-window ANTARES 2 ] 10 2 Auger m 1 c 10 IceCube V e 0 G 10 [ 0 Kimura et al. IceCube and ANTARES looked for F 4 2 10 1 EE moderate E µ ν sec 8 at 500 , observation for 2 2 − 10 Kimura et al.
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  • Gravitational Waves in Scalar–Tensor–Vector Gravity Theory

    Gravitational Waves in Scalar–Tensor–Vector Gravity Theory

    universe Article Gravitational Waves in Scalar–Tensor–Vector Gravity Theory Yunqi Liu 1,2, Wei-Liang Qian 1,2,3,* , Yungui Gong 4 and Bin Wang 1,5 1 Center for Gravitation and Cosmology, College of Physical Science and Technology, Yangzhou University, Yangzhou 225009, China; [email protected] (Y.L.); [email protected] (B.W.) 2 Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, SP 12602-810, Brazil 3 Faculdade de Engenharia de Guaratinguetá, Universidade Estadual Paulista, Guaratinguetá, SP 12516-410, Brazil 4 School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China; [email protected] 5 Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China * Correspondence: [email protected] Abstract: In this paper, we study the properties of gravitational waves in the scalar–tensor–vector gravity theory. The polarizations of the gravitational waves are investigated by analyzing the relative motion of the test particles. It is found that the interaction between the matter and vector field in the theory leads to two additional transverse polarization modes. By making use of the polarization content, the stress-energy pseudo-tensor is calculated by employing the perturbed equation method. Additionally, the relaxed field equation for the modified gravity in question is derived by using the Landau–Lifshitz formalism suitable to systems with non-negligible self-gravity. Keywords: gravitational waves; polarizations; stress-energy pseudo-tensor 1. Introduction The recent observation of gravitational waves (GWs) by the LIGO and Virgo Scientific Citation: Liu, Y.; Qian, W.-L.; Collaboration opens up a new avenue to explore gravitational physics from an entirely Gong, Y.; Wang, B.
  • GW170814 and GW170817 the LIGO/Virgo Detections of Gws from BBH and BNS

    GW170814 and GW170817 the LIGO/Virgo Detections of Gws from BBH and BNS

    GW170814 and GW170817 the LIGO/Virgo detections of GWs from BBH and BNS José Antonio Font (Universitat de València) www.uv.es/virgogroup Interferometer Detectors Michelson-Morley interferometers. Test masses separated by large distances and suspended as pendulums to isolate them from seismic noise and reduce thermal noise. Analyzing the laser interference fringes allows to control the movement of the masses during their interaction with gravitational radiation. ASTRONOMY: ROEN KELLY The (infinitesimal) change in the length of the arms originates a change in the intensity of the light (interference fringes) at the detector’s output. The Advanced Virgo interferometer The Advanced Virgo interferometer Our current network LIGO Hanford Observatory LIGO Livingston Observatory Virgo Observatory Expanded Network of Interferometers 2020+ Towards a global GW research infrastructure Noise-dominated observations The small amplitude of gravitational waves calls for an extreme reduction of the sources of noise Detectability region Seismic noise Amplitude (h) Amplitude Shot Thermal noise noise Frequency (Hz) If sufficient mergers were detected we could average orbital parameters and use mergers as standard sirens. Numerical relativity simulations needed to extract accurate gravitational waveforms. A “chirp” gravitational waveform signal signal + noise A “chirp” gravitational waveform signal signal + noise A “chirp” gravitational waveform signal signal + noise Advanced technology ultra-vacuum arms (p~10-9 mbar). Movements (vibration) of test mases (40 kg) and suspensions induced by thermal effects. high power lasers (Nd:YAG 1064 nm wavelength laser). Shot noise: fluctuations in the number of photons in the laser produce fluctuations in the signal. highly reflective mirrors (SiO2). monolythic suspension systems to isolate the detectors from vibrations.