Future Gravitational Wave Observations Stephen Fairhurst GW170817: The First Double Neutron Star Merger KITP, December 7, 2017 1
Sensitivity Evolution Advanced IGO Advanced Virgo Early (2015 16, 40 80 ) Early (2017, 20 65 ) Mid (2016 17, 80 120 ) Mid (2018 19, 65 85 ) Strain noise amplitude/hz 1/2 10 21 10 22 10 23 ate (2018 19, 120 170 ) Design (2020, 190 ) BNS-optimized (210 ) Strain noise amplitude/hz 1/2 10 21 10 22 10 23 ate (2020 21, 65 115 ) Design (2021, 125 ) BNS-optimized (140 ) 10 24 10 1 10 2 10 3 Frequency/Hz 10 24 10 1 10 2 10 3 KAGRA Frequency/Hz Opening (2018 19, 3 8 ) Early (2019 20, 8 25 ) Strain noise amplitude/hz 1/2 10 21 10 22 10 23 Mid (2020 21, 25 40 ) ate (2021 22, 40 140 ) Design (2022, 140 ) From Abbott et al, arxiv:1304.0670v4 10 24 10 1 10 2 10 3 Frequency/Hz 2
Sensitivity Evolution Early Mid ate Design 60-80 60-100 120-170 190 IGO O1 O2 O3 25-30 65-85 65-115 125 Virgo O2 O3 25-40 40-140 140 KAGRA 2015 2016 2017 2018 2019 2020 2021 2022 2023 From Abbott et al, arxiv:1304.0670v4 3
Observing scenario Epoch 2015 2016 2016 2017 2018 2019 2020+ 2024+ Planned run duration 4 months 9 months 12 months (per year) (per year) IGO 40 60 60 75 75 90 105 105 Expected burst range/ Virgo 20 40 40 50 40 70 80 KAGRA 100 IGO 40 80 80 120 120 170 190 190 Expected BNS range/ Virgo 20 65 65 85 65 115 125 KAGRA 140 IGO 60 80 60 100 Achieved BNS range/ Virgo 25 30 KAGRA Estimated BNS detections 0.002 2 0.007 30 0.04 100 0.1 200 0.4 400 Actual BNS detections 0 5 deg % within < 1 1 5 1 4 3 7 23 30 90% CR 20 deg 2 < 1 7 14 12 21 14 22 65 73 median/deg 2 460 530 230 320 120 180 110 180 9 12 Searched area % within 5 deg 2 4 6 15 21 20 26 23 29 62 67 20 deg 2 14 17 33 41 42 50 44 52 87 90 From Abbott et al, arxiv:1304.0670v4 4
ur analyses identified GW170817 as the only BNSs signal detected in O2 with a false alarm rate below 00 yr. Using a method derived from [27,178,179], and ming that the mass distribution of the components of Updated Expectations and their S systems is flat between 1 and 2 M ensionless spins are below 0.4, we are able to infer local coalescence rate density R of BNS systems. rporating Use the IGO-Virgo upper limit ofbns 12600rate Gpc 3 yr 1 from O1 a prior, R ¼ 1540 þ3200 1220 Gpc 3 yr 1. Our findings are min of 1 10 47 erg s 1, and a = 1, b = 2 and g = { 1, 0.5, 0}in Equation (21), respectively. The purple solid line refers to the base model with O3 Design min of 5 10 49 erg s 1. The four curves are normalized by imposing 40 triggered SGRB per year. As g increases, the observed rate is no longer volumetric at lower and lower redshifts, because a fraction of SGRBs becomes too dim to be detected. For reference, the red, blue and green dot-dashed curves show the local SGRB occurrence rate for min = 1 1047 erg s 1 3200 and g = { 1, 0.5, 0}, respectively. The black line and gray band show the BNS merger rate 1540 1220 Gpc 3yr 1 - + - - determined with the detection of GW170817 (Abbott et al. 2017e). For comparison, the measured SGRBs redshift distribution from Table 2 is shown in cyan, and is broadly compatible with all of the models. The dotted vertical cyan line refers to the redshift of GRB 170817A host galaxy. Extend GRB luminosity distribution down as = 5 10 49 erg s 1 : iso -g -a iso < -a iso f o( iso) = iso iso -b < < iso > { } Fit GRB rate to 40 per year observed in Fermi GBM, 161101-7 reduced interferometer response a their observation unfeasible. Con been made for short (tens of ms) a ( 500 s) gravitational-wave sign remnant at frequencies up to 4 kh latter, the data examined start at th and extend to the end of the obse 2017. With the time scales and m [193], there is no evidence of From Gravitational Waves and Gamma-Rays from a Binary Neutron Star Merger : 5
Observing scenario Epoch 2015 2016 2016 2017 2018 2019 2020+ 2024+ Planned run duration 4 months 9 months 12 months (per year) (per year) IGO 40 60 60 75 75 90 105 105 Expected burst range/ Virgo 20 40 40 50 40 70 80 KAGRA 100 IGO 40 80 80 120 120 170 190 190 Expected BNS range/ Virgo 20 65 65 85 65 115 125 KAGRA 140 IGO 60 80 60 100 Achieved BNS range/ Virgo 25 30 KAGRA Estimated BNS detections 0.002 2 0.007 30 0.04 1-50 100 0.1 6-120 200 0.4 400 Actual BNS detections 0 1 5 deg % within < 1 1 5 1 4 3 7 23 30 90% CR 20 deg 2 < 1 7 14 12 21 14 22 65 73 median/deg 2 460 530 230 320 120 180 110 180 9 12 Searched area % within 5 deg 2 4 6 15 21 20 26 23 29 62 67 20 deg 2 14 17 33 41 42 50 44 52 87 90 Estimated GW-GRB 0.1-1.4 0.3-1.7 Actual GW-GRB 1 - - From Gravitational Waves and Gamma-Rays from a Binary Neutron Star Merger 6
Expected O3 Observations Signal to noise ratio GW170817 Distance and Orientation Relative Sensitivity Rate density 7
Measuring Inclination Face-on signals are left/right circularly polarized To bound inclination, need to observe difference from circular polarization Require good sensitivity to both GW polarizations 8
Measuring Inclination Face-on signals are left/right circularly polarized Volume weighted sensitivity To bound inclination, need to observe difference from circular polarization Require good sensitivity to both GW polarizations Relative sensitivity to 2nd polarization 9
GW only observations Will measure chirp mass m1 M well, not component masses (Hannam+, 2013) 1.4 1.2 1.0 0.8 0.6 χ NS 0 χ 0.05 χ NS 0.05 1.5 2.0 2.5 3.0 Hannam et al. 1.5 2.0 2.5 3.0 3.5 m 2 M Figure Will 1. increasingly move 0.30 0.25 0.20 0.15 0.10 0.05 0.00 m 2 M towards population based statements on masses, spins, equation of state m1 p (m1) 10 1 10 0 10 1 10 2 10 1 10 2 m 1 (M ) FIG. 8. The posterior probability distribution for the primary component mass m 1 of binary black holes inferred from the hierarchical analysis. The black line gives the posterior median as a function of mass, and the dark and light grey bands give the 50% and 90% credible intervals. The colored vertical bands give the 50% credible interval from the posterior on m 1 from the analyses of (left to right) GW151226, VT151012, GW170104, and GW150914. The marginal mass distribution is a power law for m 1 apple 50 M, and turns over for m 1 50 M due to the constraint on the two-dimensional population distribution that m 1 + m 2 apple 100 M. GW170104 supplemental material 10
GRB only observations Dedicated search [ 5, +1) s from time of short GRBs With no detection, place exclusion Exclusion confidence at 54 Example: GRB150906B 90% exclusion distance (max 30 o opening) From Abbott et al, arxiv:1611.07947 11
GRB only observation Population exclusion from O1 With future observations, begin to restrict fraction of nearby GRBs Abbott et al. From Abbott et al, arxiv:1611.07947 12
Discussion Expect binary neutron star merger observations in upcoming IGO-Virgo-KAGRA observing runs Majority of sources expected to be weaker and at greater distance than GW170817 Joint, GW only and EM only observations allow us to probe NS properties, GRBs and kilonovae. 13
Science Case Team Chairs: Kalogera, Sathayprakash Register https://gw-astronomy.org/ registry/pages/public/gwic-3gsct-wg-sign-up 14