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Binary Black Hole Observations with Advanced LIGO

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Binary Black Hole Observations with Advanced LIGO Binary black hole observations with Advanced LIGO LIGO - G1700996 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Outline 1. Binary Black Holes (BBH) in the first observing run. a. GW150914 b. GW151226 c. LVT151012 2. The distribution of masses 3. The distribution of spins 4. The distribution of amplitudes 5. Inference of the BBH coalescence rate 6. conclusion 2 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 BBH in LIGO’s first observing run > 5 σ > 5 σ Credit LIGO 3 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 GW150914 Phys. Rev. Lett. 116, 061102 (2016) 4 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 GW150914 Phys. Rev. Lett. 116, 061102 (2016) 5 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 GW150914 Phys. Rev. Lett. 116, 241102 (2016) 6 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 GW150914 Phys. Rev. Lett. 116, 241102 (2016) 7 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 GW151226 Phys. Rev. Lett. 116, 241103 (2016) 8 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 GW151226 Phys. Rev. Lett. 116, 241103 (2016) 9 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 GW151226 Phys. Rev. Lett. 116, 241103 (2016) 10 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 GW151226 Phys. Rev. Lett. 116, 241103 (2016) 11 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 LVT151012 LVT151012 LVT151012 Phys. Rev. X 6, 041015 (2016) 12 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 LVT151012 13 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Mass distribution Credit LIGO 14 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 BBH mass function Slope is -α 1 ) dm ) 1 Log p(m Log Phys. Rev. X 6, 041015 (2016) -⍺ 1 m / 10 100 p(m ) dm ∝ m dm 1 1 1 1 1 M☉ The mass function may help us to tell the origin story of LIGO’s black holes 15 Chad Hanna - Phys 590 - April 14, 2017 Spin distribution Phys. Rev. X 6, 041015 (2016) GW150914 LVT151012 GW1512226 16 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Spin distribution Effective spin L^ ^ L ^L GW150914 LVT151012 GW151226 [-0.14,0.14] [-0.2,0.3] [-0.1,0.2] eff = -0.06 eff = 0 eff = 0.21 Only GW151226 excludes eff = 0 within the 90% confidence interval. 17 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Amplitude distribution LVT 151012 Probability of GW ~87% Phys. Rev. X 6, 041015 (2016) 18 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 BBH Coalescence Rate Phys. Rev. X 6, 041015 (2016) 19 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Conclusion 1. Advanced LIGO detected two definitive binary black hole mergers in its first observing run along with a third promising candidate 2. The black holes are heavier than known X-ray binary black holes 3. Two of the three black hole binaries are consistent with zero spin, one, GW151226 has a primary mass spin of at least 0.2 4. The mass distribution is consistent with a power law with slope -2.5 5. The binary black hole rate is still uncertain and model dependent but is plausibly in the range of a few to a few hundred mergers per year per gigaparsec cubed. 6. Advanced LIGO’s second observing run begin at November’s end 2016 and is ongoing through August 2017. 20 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Introducing GW170104 21 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Introducing GW170104 LIGO Scientific Collaboration and Virgo Collaboration to appear in PRL 22 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Introducing GW170104 < 1 / 70,000 years! LIGO Scientific Collaboration and Virgo Collaboration to appear in PRL 23 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Introducing GW170104 LIGO Scientific Collaboration and Virgo Collaboration to appear in PRL 24 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Introducing GW170104 LIGO Scientific Collaboration and Virgo Collaboration to appear in PRL 25 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Amongst the other LIGO BHs Credit LIGO 26 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Amongst the other LIGO BHs Effective spin L L L L GW150914 GW170104 LVT151012 GW151226 [-0.14,0.14] [-0.3,0.21] [-0.2,0.3] [-0.1,0.2] eff = -0.06 eff = -0.12 eff = 0 eff = 0.21 Only GW151226 excludes eff = 0 within the 90% confidence interval. 27 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017 Introducing GW170104 28 Chad Hanna - Binary black hole observations with Advanced LIGO - May 31, 2017.
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