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The field of gravitational wave astronomy has grown remarkably since the first direct detection of gravitational waves on 14th September 2015. The signal, originating from the merger of two black holes, was detected by the two US-based Advanced LIGO interferometers in Hanford (Washington State) and Livingston (Louisiana). The second observing run of the Advanced LIGO and Virgo detectors marked the first detection of a binary neutron star merger, along with its electromagnetic counterparts. The optical follow-up of the merger led to the first confirmed observations of a kilonova, an electromagnetic counterpart to binary neutron star and neutron star-black hole mergers whose existence was first predicted in 1970s. Following the multimessenger observations of the binary neutron star merger GW170817, constraints were put on the rate of expansion of the Universe using both gravitational wave and electromagnetic data. These measurements could help us understand the current tension between early-Universe and late-Universe measurements of the Hubble constant H0. The use of gravitational wave signals for measuring the rate of expansion of the Universe was proposed by Schutz in 1986. Compact binary coalescences can be used as distance markers, a gravitational wave analogue to standard candles: "Standard Sirens". Measurements of the Hubble constant from standard sirens are independent from previous methods of constraining H0. Bright sirens are gravitational wave signals that are detected coincidentally with electromagnetic signatures. These "bright" gravitational wave sirens are powerful cosmological probes, allowing us to extract information on both the distance and the redshift of the source. It is therefore important to maximise these coincident detections, and to carefully calibrate the data extracted from any standard siren. The work presented in this thesis can be divided into three main topics, all under the umbrella of maximising scientific returns from observations of

The field of gravitational wave astronomy has grown remarkably since the first direct detection of gravitational waves on 14th September 2015. The signal, originating from the merger of two black holes, was detected by the two US-based Advanced LIGO interferometers in Hanford (Washington State) and Livingston (Louisiana). The second observing run of the Advanced LIGO and Virgo detectors marked the first detection of a binary neutron star merger, along with its electromagnetic counterparts. The optical follow-up of the merger led to the first confirmed observations of a kilonova, an electromagnetic counterpart to binary neutron star and neutron star-black hole mergers whose existence was first predicted in 1970s. Following the multimessenger observations of the binary neutron star merger GW170817, constraints were put on the rate of expansion of the Universe using both gravitational wave and electromagnetic data. These measurements could help us understand the current tension between early-Universe and late-Universe measurements of the Hubble constant H0. The use of gravitational wave signals for measuring the rate of expansion of the Universe was proposed by Schutz in 1986. Compact binary coalescences can be used as distance markers, a gravitational wave analogue to standard candles: "Standard Sirens". Measurements of the Hubble constant from standard sirens are independent from previous methods of constraining H0. Bright sirens are gravitational wave signals that are detected coincidentally with electromagnetic signatures. These "bright" gravitational wave sirens are powerful cosmological probes, allowing us to extract information on both the distance and the redshift of the source. It is therefore important to maximise these coincident detections, and to carefully calibrate the data extracted from any standard siren. The work presented in this thesis can be divided into three main topics, all under the umbrella of maximising scientific returns from observations of

The use of gravitational wave observations from compact binary inspirals as standard sirens was first proposed by Schutz in 1986. Following the recent observations of compact binary coalescences by the Advanced LIGO detectors and the first standard siren measurement of the Hubble constant with the binary neutron star merger GW170817, and in anticipation of future detections during upcoming observing runs, it is useful to further investigate standard sirens, the gravitational wave analogues of standard candles, as an alternative way to measure the Hubble constant. Compact binary inspirals are well modelled, and their luminosity distance can be obtained from GW observations. From these distance measurements and using redshifts from EM galaxy catalogues and Bayesian inference, it is possible to assign a probability to each host galaxy, and a value for the Hubble constant can be obtained. While a redshift can sometimes be obtained from multi-messenger observations of binary neutron star coalescences, binary black hole mergers are not expected to produce electromagnetic signals, making statistical approaches an important tool in cosmology using gravitational waves. In this project, an investigation of statistical methods of measuring the Hubble constant with standard sirens is carried out using simulated data, to find out how well we can constrain the Hubble constant and to characterise the biases due to selection effects coming from the incompleteness of EM galaxy catalogues. Results are obtained for a range of aLIGO sensitivities, using both binary black hole and binary neutron star mergers as standard sirens. This constitutes an independent measurement of the Hubble constant that is competitive with other methods.

The use of gravitational wave observations from compact binary inspirals as standard sirens was first proposed by Schutz in 1986. Following the recent observations of compact binary coalescences by the Advanced LIGO detectors and the first standard siren measurement of the Hubble constant with the binary neutron star merger GW170817, and in anticipation of future detections during upcoming observing runs, it is useful to further investigate standard sirens, the gravitational wave analogues of standard candles, as an alternative way to measure the Hubble constant. Compact binary inspirals are well modelled, and their luminosity distance can be obtained from GW observations. From these distance measurements and using redshifts from EM galaxy catalogues and Bayesian inference, it is possible to assign a probability to each host galaxy, and a value for the Hubble constant can be obtained. While a redshift can sometimes be obtained from multi-messenger observations of binary neutron star coalescences, binary black hole mergers are not expected to produce electromagnetic signals, making statistical approaches an important tool in cosmology using gravitational waves. In this project, an investigation of statistical methods of measuring the Hubble constant with standard sirens is carried out using simulated data, to find out how well we can constrain the Hubble constant and to characterise the biases due to selection effects coming from the incompleteness of EM galaxy catalogues. Results are obtained for a range of aLIGO sensitivities, using both binary black hole and binary neutron star mergers as standard sirens. This constitutes an independent measurement of the Hubble constant that is competitive with other methods.

The use of gravitational wave observations from compact binary inspirals as standard sirens was first proposed by Schutz in 1986. Following the recent observations of compact binary coalescences by the Advanced LIGO detectors and the first standard siren measurement of the Hubble constant with the binary neutron star merger GW170817, and in anticipation of future detections during upcoming observing runs, it is useful to further investigate standard sirens, the gravitational wave analogues of standard candles, as an alternative way to measure the Hubble constant. Compact binary inspirals are well modelled, and their luminosity distance can be obtained from GW observations. From these distance measurements and using redshifts from EM galaxy catalogues and Bayesian inference, it is possible to assign a probability to each host galaxy, and a value for the Hubble constant can be obtained. While a redshift can sometimes be obtained from multi-messenger observations of binary neutron star coalescences, binary black hole mergers are not expected to produce electromagnetic signals, making statistical approaches an important tool in cosmology using gravitational waves. In this project, an investigation of statistical methods of measuring the Hubble constant with standard sirens is carried out using simulated data, to find out how well we can constrain the Hubble constant and to characterise the biases due to selection effects coming from the incompleteness of EM galaxy catalogues. Results are obtained for a range of aLIGO sensitivities, using both binary black hole and binary neutron star mergers as standard sirens. This constitutes an independent measurement of the Hubble constant that is competitive with other methods.

The use of gravitational wave observations from compact binary inspirals as standard sirens was first proposed by Schutz in 1986. Following the recent observations of compact binary coalescences by the Advanced LIGO detectors and the first standard siren measurement of the Hubble constant with the binary neutron star merger GW170817, and in anticipation of future detections during upcoming observing runs, it is useful to further investigate standard sirens, the gravitational wave analogues of standard candles, as an alternative way to measure the Hubble constant. Compact binary inspirals are well modelled, and their luminosity distance can be obtained from GW observations. From these distance measurements and using redshifts from EM galaxy catalogues and Bayesian inference, it is possible to assign a probability to each host galaxy, and a value for the Hubble constant can be obtained. While a redshift can sometimes be obtained from multi-messenger observations of binary neutron star coalescences, binary black hole mergers are not expected to produce electromagnetic signals, making statistical approaches an important tool in cosmology using gravitational waves. In this project, an investigation of statistical methods of measuring the Hubble constant with standard sirens is carried out using simulated data, to find out how well we can constrain the Hubble constant and to characterise the biases due to selection effects coming from the incompleteness of EM galaxy catalogues. Results are obtained for a range of aLIGO sensitivities, using both binary black hole and binary neutron star mergers as standard sirens. This constitutes an independent measurement of the Hubble constant that is competitive with other methods.