{
  "events": {
    "GW230518_125908-v1": {
      "commonName": "GW230518_125908",
      "version": 1,
      "catalog.shortName": "GWTC-4.0",
      "GPS": 1368449966.2,
      "gracedb_id": "S230518h",
      "reference": "/GWTC-4.0/",
      "jsonurl": "https://gwosc.org/eventapi/json/GWTC-4.0/GW230518_125908/v1",
      "mass_1_source": 8.17,
      "mass_1_source_lower": -0.92,
      "mass_1_source_upper": 0.84,
      "mass_1_source_unit": "M_sun",
      "mass_2_source": 1.45,
      "mass_2_source_lower": -0.1,
      "mass_2_source_upper": 0.13,
      "mass_2_source_unit": "M_sun",
      "network_matched_filter_snr": 14.1,
      "network_matched_filter_snr_lower": null,
      "network_matched_filter_snr_upper": null,
      "network_matched_filter_snr_unit": "",
      "luminosity_distance": 236.0,
      "luminosity_distance_lower": -96.0,
      "luminosity_distance_upper": 108.0,
      "luminosity_distance_unit": "Mpc",
      "chi_eff": -0.01,
      "chi_eff_lower": -0.11,
      "chi_eff_upper": 0.09,
      "chi_eff_unit": "",
      "total_mass_source": 9.61,
      "total_mass_source_lower": -0.79,
      "total_mass_source_upper": 0.76,
      "total_mass_source_unit": "M_sun",
      "chirp_mass_source": 2.8,
      "chirp_mass_source_lower": -0.06,
      "chirp_mass_source_upper": 0.06,
      "chirp_mass_source_unit": "M_sun",
      "chirp_mass": null,
      "chirp_mass_lower": null,
      "chirp_mass_upper": null,
      "chirp_mass_unit": null,
      "redshift": 0.05,
      "redshift_lower": -0.02,
      "redshift_upper": 0.02,
      "redshift_unit": "",
      "far": 1e-05,
      "far_lower": null,
      "far_upper": null,
      "far_unit": "1/yr",
      "p_astro": 0.99,
      "p_astro_lower": null,
      "p_astro_upper": null,
      "p_astro_unit": "",
      "final_mass_source": null,
      "final_mass_source_lower": null,
      "final_mass_source_upper": null,
      "final_mass_source_unit": null,
      "strain": [
        {
          "GPSstart": 1368449024,
          "detector": "H1",
          "sampling_rate": 16384,
          "duration": 4096,
          "format": "gwf",
          "url": "https://gwosc.org/archive/data/O4a_16KHZ_R1/1368391680/H-H1_GWOSC_O4a_16KHZ_R1-1368449024-4096.gwf"
        },
        {
          "GPSstart": 1368449024,
          "detector": "H1",
          "sampling_rate": 16384,
          "duration": 4096,
          "format": "hdf5",
          "url": "https://gwosc.org/archive/data/O4a_16KHZ_R1/1368391680/H-H1_GWOSC_O4a_16KHZ_R1-1368449024-4096.hdf5"
        },
        {
          "GPSstart": 1368449024,
          "detector": "H1",
          "sampling_rate": 4096,
          "duration": 4096,
          "format": "gwf",
          "url": "https://gwosc.org/archive/data/O4a_4KHZ_R1/1368391680/H-H1_GWOSC_O4a_4KHZ_R1-1368449024-4096.gwf"
        },
        {
          "GPSstart": 1368449024,
          "detector": "H1",
          "sampling_rate": 4096,
          "duration": 4096,
          "format": "hdf5",
          "url": "https://gwosc.org/archive/data/O4a_4KHZ_R1/1368391680/H-H1_GWOSC_O4a_4KHZ_R1-1368449024-4096.hdf5"
        },
        {
          "GPSstart": 1368449024,
          "detector": "L1",
          "sampling_rate": 16384,
          "duration": 4096,
          "format": "gwf",
          "url": "https://gwosc.org/archive/data/O4a_16KHZ_R1/1368391680/L-L1_GWOSC_O4a_16KHZ_R1-1368449024-4096.gwf"
        },
        {
          "GPSstart": 1368449024,
          "detector": "L1",
          "sampling_rate": 16384,
          "duration": 4096,
          "format": "hdf5",
          "url": "https://gwosc.org/archive/data/O4a_16KHZ_R1/1368391680/L-L1_GWOSC_O4a_16KHZ_R1-1368449024-4096.hdf5"
        },
        {
          "GPSstart": 1368449024,
          "detector": "L1",
          "sampling_rate": 4096,
          "duration": 4096,
          "format": "gwf",
          "url": "https://gwosc.org/archive/data/O4a_4KHZ_R1/1368391680/L-L1_GWOSC_O4a_4KHZ_R1-1368449024-4096.gwf"
        },
        {
          "GPSstart": 1368449024,
          "detector": "L1",
          "sampling_rate": 4096,
          "duration": 4096,
          "format": "hdf5",
          "url": "https://gwosc.org/archive/data/O4a_4KHZ_R1/1368391680/L-L1_GWOSC_O4a_4KHZ_R1-1368449024-4096.hdf5"
        }
      ],
      "parameters": {
        "GWTC-4.0_gstlal_GW230518_125908": {
          "waveform_family": "na",
          "data_url": "",
          "date_added": "2025-08-26",
          "is_preferred": false,
          "pipeline_type": "search",
          "links": {},
          "far": 1e-05,
          "far_lower": null,
          "far_upper": null,
          "far_unit": "1/yr",
          "far_meta": "na",
          "network_matched_filter_snr": 13.7,
          "network_matched_filter_snr_lower": null,
          "network_matched_filter_snr_upper": null,
          "network_matched_filter_snr_unit": "",
          "network_matched_filter_snr_meta": "na",
          "p_astro": 0.99,
          "p_astro_lower": null,
          "p_astro_upper": null,
          "p_astro_unit": "",
          "p_astro_meta": "na"
        },
        "GWTC-4.0_GW230518_125908_C00:IMRPhenomNSBH:LowSpin_CC1_PE": {
          "waveform_family": "C00:IMRPhenomNSBH:LowSpin",
          "data_url": "https://zenodo.org/api/records/16053484/files/IGWN-GWTC4p0-0f954158d_720-GW230518_125908-combined_PEDataRelease.hdf5/content",
          "date_added": "2025-08-26",
          "is_preferred": false,
          "pipeline_type": "pe",
          "links": {
            "na": "https://doi.org/10.5281/zenodo.16053483"
          },
          "chirp_mass_source": 2.79,
          "chirp_mass_source_lower": -0.06,
          "chirp_mass_source_upper": 0.06,
          "chirp_mass_source_unit": "M_sun",
          "chirp_mass_source_meta": "na",
          "chi_eff": -0.01,
          "chi_eff_lower": -0.18,
          "chi_eff_upper": 0.11,
          "chi_eff_unit": "",
          "chi_eff_meta": "na",
          "final_mass_source": 9.4,
          "final_mass_source_lower": -1.3,
          "final_mass_source_upper": 1.2,
          "final_mass_source_unit": "M_sun",
          "final_mass_source_meta": "na",
          "luminosity_distance": 250.0,
          "luminosity_distance_lower": -110.0,
          "luminosity_distance_upper": 120.0,
          "luminosity_distance_unit": "Mpc",
          "luminosity_distance_meta": "na",
          "mass_1_source": 8.1,
          "mass_1_source_lower": -1.6,
          "mass_1_source_upper": 1.3,
          "mass_1_source_unit": "M_sun",
          "mass_1_source_meta": "na",
          "mass_2_source": 1.44,
          "mass_2_source_lower": -0.15,
          "mass_2_source_upper": 0.26,
          "mass_2_source_unit": "M_sun",
          "mass_2_source_meta": "na",
          "redshift": 0.06,
          "redshift_lower": -0.02,
          "redshift_upper": 0.02,
          "redshift_unit": "",
          "redshift_meta": "na",
          "total_mass_source": 9.6,
          "total_mass_source_lower": -1.3,
          "total_mass_source_upper": 1.2,
          "total_mass_source_unit": "M_sun",
          "total_mass_source_meta": "na"
        },
        "GWTC-4.0_GW230518_125908_C00:IMRPhenomNSBH:LowSpin_RW1_PE": {
          "waveform_family": "C00:IMRPhenomNSBH:LowSpin",
          "data_url": "https://zenodo.org/api/records/17014085/files/IGWN-GWTC4p0-1a206db3d_721-GW230518_125908-combined_PEDataRelease.hdf5/content",
          "date_added": "2025-10-28",
          "is_preferred": false,
          "pipeline_type": "pe",
          "links": {
            "Reweighted PE Data Products in Zenodo": "https://doi.org/10.5281/zenodo.17014085"
          },
          "chirp_mass_source": 2.79,
          "chirp_mass_source_lower": -0.06,
          "chirp_mass_source_upper": 0.06,
          "chirp_mass_source_unit": "M_sun",
          "chirp_mass_source_meta": "na",
          "chi_eff": -0.01,
          "chi_eff_lower": -0.17,
          "chi_eff_upper": 0.11,
          "chi_eff_unit": "",
          "chi_eff_meta": "na",
          "final_mass_source": 9.4,
          "final_mass_source_lower": -1.3,
          "final_mass_source_upper": 1.2,
          "final_mass_source_unit": "M_sun",
          "final_mass_source_meta": "na",
          "luminosity_distance": 250.0,
          "luminosity_distance_lower": -110.0,
          "luminosity_distance_upper": 120.0,
          "luminosity_distance_unit": "Mpc",
          "luminosity_distance_meta": "na",
          "mass_1_source": 8.1,
          "mass_1_source_lower": -1.6,
          "mass_1_source_upper": 1.3,
          "mass_1_source_unit": "M_sun",
          "mass_1_source_meta": "na",
          "mass_2_source": 1.44,
          "mass_2_source_lower": -0.15,
          "mass_2_source_upper": 0.26,
          "mass_2_source_unit": "M_sun",
          "mass_2_source_meta": "na",
          "redshift": 0.05,
          "redshift_lower": -0.02,
          "redshift_upper": 0.02,
          "redshift_unit": "",
          "redshift_meta": "na",
          "total_mass_source": 9.6,
          "total_mass_source_lower": -1.3,
          "total_mass_source_upper": 1.2,
          "total_mass_source_unit": "M_sun",
          "total_mass_source_meta": "na"
        },
        "GWTC-4.0_GW230518_125908_C00:IMRPhenomPv2-NRTidalv2:LowSpin_RW2_PE": {
          "waveform_family": "C00:IMRPhenomPv2-NRTidalv2:LowSpin",
          "data_url": "https://zenodo.org/api/records/17014085/files/IGWN-GWTC4p0-1a206db3d_721-GW230518_125908-combined_PEDataRelease.hdf5/content",
          "date_added": "2025-10-28",
          "is_preferred": false,
          "pipeline_type": "pe",
          "links": {
            "Reweighted PE Data Products in Zenodo": "https://doi.org/10.5281/zenodo.17014085"
          },
          "chirp_mass_source": 2.79,
          "chirp_mass_source_lower": -0.06,
          "chirp_mass_source_upper": 0.06,
          "chirp_mass_source_unit": "M_sun",
          "chirp_mass_source_meta": "na",
          "chi_eff": -0.02,
          "chi_eff_lower": -0.39,
          "chi_eff_upper": 0.11,
          "chi_eff_unit": "",
          "chi_eff_meta": "na",
          "luminosity_distance": 254.0,
          "luminosity_distance_lower": -96.0,
          "luminosity_distance_upper": 116.0,
          "luminosity_distance_unit": "Mpc",
          "luminosity_distance_meta": "na",
          "mass_1_source": 8.0,
          "mass_1_source_lower": -3.1,
          "mass_1_source_upper": 1.2,
          "mass_1_source_unit": "M_sun",
          "mass_1_source_meta": "na",
          "mass_2_source": 1.46,
          "mass_2_source_lower": -0.15,
          "mass_2_source_upper": 0.69,
          "mass_2_source_unit": "M_sun",
          "mass_2_source_meta": "na",
          "redshift": 0.06,
          "redshift_lower": -0.02,
          "redshift_upper": 0.02,
          "redshift_unit": "",
          "redshift_meta": "na",
          "total_mass_source": 9.5,
          "total_mass_source_lower": -2.4,
          "total_mass_source_upper": 1.1,
          "total_mass_source_unit": "M_sun",
          "total_mass_source_meta": "na"
        },
        "GWTC-4.0_GW230518_125908_C00:IMRPhenomXPHM-SpinTaylor_RW3_PE": {
          "waveform_family": "C00:IMRPhenomXPHM-SpinTaylor",
          "data_url": "https://zenodo.org/api/records/17014085/files/IGWN-GWTC4p0-1a206db3d_721-GW230518_125908-combined_PEDataRelease.hdf5/content",
          "date_added": "2025-10-28",
          "is_preferred": true,
          "pipeline_type": "pe",
          "links": {
            "Reweighted PE Data Products in Zenodo": "https://doi.org/10.5281/zenodo.17014085"
          },
          "chirp_mass_source": 2.8,
          "chirp_mass_source_lower": -0.06,
          "chirp_mass_source_upper": 0.06,
          "chirp_mass_source_unit": "M_sun",
          "chirp_mass_source_meta": "na",
          "chi_eff": -0.01,
          "chi_eff_lower": -0.11,
          "chi_eff_upper": 0.09,
          "chi_eff_unit": "",
          "chi_eff_meta": "na",
          "luminosity_distance": 236.0,
          "luminosity_distance_lower": -96.0,
          "luminosity_distance_upper": 108.0,
          "luminosity_distance_unit": "Mpc",
          "luminosity_distance_meta": "na",
          "mass_1_source": 8.17,
          "mass_1_source_lower": -0.92,
          "mass_1_source_upper": 0.84,
          "mass_1_source_unit": "M_sun",
          "mass_1_source_meta": "na",
          "mass_2_source": 1.45,
          "mass_2_source_lower": -0.1,
          "mass_2_source_upper": 0.13,
          "mass_2_source_unit": "M_sun",
          "mass_2_source_meta": "na",
          "redshift": 0.05,
          "redshift_lower": -0.02,
          "redshift_upper": 0.02,
          "redshift_unit": "",
          "redshift_meta": "na",
          "total_mass_source": 9.61,
          "total_mass_source_lower": -0.79,
          "total_mass_source_upper": 0.76,
          "total_mass_source_unit": "M_sun",
          "total_mass_source_meta": "na"
        },
        "GWTC-4.0_GW230518_125908_C00:SEOBNRv4_ROM_NRTidalv2_NSBH:LowSpin_CC4_PE": {
          "waveform_family": "C00:SEOBNRv4_ROM_NRTidalv2_NSBH:LowSpin",
          "data_url": "https://zenodo.org/api/records/16053484/files/IGWN-GWTC4p0-0f954158d_720-GW230518_125908-combined_PEDataRelease.hdf5/content",
          "date_added": "2025-08-26",
          "is_preferred": false,
          "pipeline_type": "pe",
          "links": {
            "na": "https://doi.org/10.5281/zenodo.16053483"
          },
          "chirp_mass_source": 2.8,
          "chirp_mass_source_lower": -0.06,
          "chirp_mass_source_upper": 0.06,
          "chirp_mass_source_unit": "M_sun",
          "chirp_mass_source_meta": "na",
          "chi_eff": -0.03,
          "chi_eff_lower": -0.24,
          "chi_eff_upper": 0.14,
          "chi_eff_unit": "",
          "chi_eff_meta": "na",
          "final_mass_source": 9.2,
          "final_mass_source_lower": -1.6,
          "final_mass_source_upper": 1.5,
          "final_mass_source_unit": "M_sun",
          "final_mass_source_meta": "na",
          "luminosity_distance": 240.0,
          "luminosity_distance_lower": -100.0,
          "luminosity_distance_upper": 120.0,
          "luminosity_distance_unit": "Mpc",
          "luminosity_distance_meta": "na",
          "mass_1_source": 7.9,
          "mass_1_source_lower": -2.0,
          "mass_1_source_upper": 1.6,
          "mass_1_source_unit": "M_sun",
          "mass_1_source_meta": "na",
          "mass_2_source": 1.48,
          "mass_2_source_lower": -0.19,
          "mass_2_source_upper": 0.38,
          "mass_2_source_unit": "M_sun",
          "mass_2_source_meta": "na",
          "redshift": 0.05,
          "redshift_lower": -0.02,
          "redshift_upper": 0.02,
          "redshift_unit": "",
          "redshift_meta": "na",
          "total_mass_source": 9.4,
          "total_mass_source_lower": -1.6,
          "total_mass_source_upper": 1.4,
          "total_mass_source_unit": "M_sun",
          "total_mass_source_meta": "na"
        },
        "GWTC-4.0_GW230518_125908_C00:SEOBNRv4_ROM_NRTidalv2_NSBH:LowSpin_RW4_PE": {
          "waveform_family": "C00:SEOBNRv4_ROM_NRTidalv2_NSBH:LowSpin",
          "data_url": "https://zenodo.org/api/records/17014085/files/IGWN-GWTC4p0-1a206db3d_721-GW230518_125908-combined_PEDataRelease.hdf5/content",
          "date_added": "2025-10-28",
          "is_preferred": false,
          "pipeline_type": "pe",
          "links": {
            "Reweighted PE Data Products in Zenodo": "https://doi.org/10.5281/zenodo.17014085"
          },
          "chirp_mass_source": 2.8,
          "chirp_mass_source_lower": -0.06,
          "chirp_mass_source_upper": 0.06,
          "chirp_mass_source_unit": "M_sun",
          "chirp_mass_source_meta": "na",
          "chi_eff": -0.03,
          "chi_eff_lower": -0.24,
          "chi_eff_upper": 0.15,
          "chi_eff_unit": "",
          "chi_eff_meta": "na",
          "final_mass_source": 9.2,
          "final_mass_source_lower": -1.7,
          "final_mass_source_upper": 1.5,
          "final_mass_source_unit": "M_sun",
          "final_mass_source_meta": "na",
          "luminosity_distance": 240.0,
          "luminosity_distance_lower": -100.0,
          "luminosity_distance_upper": 120.0,
          "luminosity_distance_unit": "Mpc",
          "luminosity_distance_meta": "na",
          "mass_1_source": 7.9,
          "mass_1_source_lower": -2.0,
          "mass_1_source_upper": 1.6,
          "mass_1_source_unit": "M_sun",
          "mass_1_source_meta": "na",
          "mass_2_source": 1.48,
          "mass_2_source_lower": -0.19,
          "mass_2_source_upper": 0.38,
          "mass_2_source_unit": "M_sun",
          "mass_2_source_meta": "na",
          "redshift": 0.05,
          "redshift_lower": -0.02,
          "redshift_upper": 0.02,
          "redshift_unit": "",
          "redshift_meta": "na",
          "total_mass_source": 9.4,
          "total_mass_source_lower": -1.6,
          "total_mass_source_upper": 1.5,
          "total_mass_source_unit": "M_sun",
          "total_mass_source_meta": "na"
        },
        "GWTC-4.0_GW230518_125908_NRTidalv2:LowSpin_CC2_PE": {
          "waveform_family": "NRTidalv2:LowSpin",
          "data_url": "https://zenodo.org/api/records/16053484/files/IGWN-GWTC4p0-0f954158d_720-GW230518_125908-combined_PEDataRelease.hdf5/content",
          "date_added": "2025-08-26",
          "is_preferred": false,
          "pipeline_type": "pe",
          "links": {
            "na": "https://doi.org/10.5281/zenodo.16053483"
          },
          "chirp_mass_source": 2.79,
          "chirp_mass_source_lower": -0.06,
          "chirp_mass_source_upper": 0.06,
          "chirp_mass_source_unit": "M_sun",
          "chirp_mass_source_meta": "na",
          "chi_eff": -0.02,
          "chi_eff_lower": -0.39,
          "chi_eff_upper": 0.11,
          "chi_eff_unit": "",
          "chi_eff_meta": "na",
          "luminosity_distance": 254.0,
          "luminosity_distance_lower": -95.0,
          "luminosity_distance_upper": 118.0,
          "luminosity_distance_unit": "Mpc",
          "luminosity_distance_meta": "na",
          "mass_1_source": 8.0,
          "mass_1_source_lower": -3.1,
          "mass_1_source_upper": 1.2,
          "mass_1_source_unit": "M_sun",
          "mass_1_source_meta": "na",
          "mass_2_source": 1.46,
          "mass_2_source_lower": -0.15,
          "mass_2_source_upper": 0.69,
          "mass_2_source_unit": "M_sun",
          "mass_2_source_meta": "na",
          "redshift": 0.06,
          "redshift_lower": -0.02,
          "redshift_upper": 0.02,
          "redshift_unit": "",
          "redshift_meta": "na",
          "total_mass_source": 9.4,
          "total_mass_source_lower": -2.4,
          "total_mass_source_upper": 1.1,
          "total_mass_source_unit": "M_sun",
          "total_mass_source_meta": "na"
        },
        "GWTC-4.0_GW230518_125908_SpinTaylor_CC3_PE": {
          "waveform_family": "SpinTaylor",
          "data_url": "https://zenodo.org/api/records/16053484/files/IGWN-GWTC4p0-0f954158d_720-GW230518_125908-combined_PEDataRelease.hdf5/content",
          "date_added": "2025-08-26",
          "is_preferred": false,
          "pipeline_type": "pe",
          "links": {
            "na": "https://doi.org/10.5281/zenodo.16053483"
          },
          "chirp_mass_source": 2.8,
          "chirp_mass_source_lower": -0.06,
          "chirp_mass_source_upper": 0.06,
          "chirp_mass_source_unit": "M_sun",
          "chirp_mass_source_meta": "na",
          "chi_eff": -0.01,
          "chi_eff_lower": -0.11,
          "chi_eff_upper": 0.09,
          "chi_eff_unit": "",
          "chi_eff_meta": "na",
          "luminosity_distance": 237.0,
          "luminosity_distance_lower": -98.0,
          "luminosity_distance_upper": 108.0,
          "luminosity_distance_unit": "Mpc",
          "luminosity_distance_meta": "na",
          "mass_1_source": 8.18,
          "mass_1_source_lower": -0.94,
          "mass_1_source_upper": 0.83,
          "mass_1_source_unit": "M_sun",
          "mass_1_source_meta": "na",
          "mass_2_source": 1.45,
          "mass_2_source_lower": -0.11,
          "mass_2_source_upper": 0.14,
          "mass_2_source_unit": "M_sun",
          "mass_2_source_meta": "na",
          "redshift": 0.05,
          "redshift_lower": -0.02,
          "redshift_upper": 0.02,
          "redshift_unit": "",
          "redshift_meta": "na",
          "total_mass_source": 9.62,
          "total_mass_source_lower": -0.81,
          "total_mass_source_upper": 0.74,
          "total_mass_source_unit": "M_sun",
          "total_mass_source_meta": "na"
        },
        "GWTC-4.0_MBTA_GW230518_125908": {
          "waveform_family": "na",
          "data_url": "",
          "date_added": "2025-08-26",
          "is_preferred": false,
          "pipeline_type": "search",
          "links": {},
          "far": 1e-05,
          "far_lower": null,
          "far_upper": null,
          "far_unit": "1/yr",
          "far_meta": "na",
          "network_matched_filter_snr": 14.1,
          "network_matched_filter_snr_lower": null,
          "network_matched_filter_snr_upper": null,
          "network_matched_filter_snr_unit": "",
          "network_matched_filter_snr_meta": "na",
          "p_astro": 0.99,
          "p_astro_lower": null,
          "p_astro_upper": null,
          "p_astro_unit": "",
          "p_astro_meta": "na"
        },
        "GWTC-4.0_pycbc_GW230518_125908": {
          "waveform_family": "na",
          "data_url": "",
          "date_added": "2025-08-26",
          "is_preferred": false,
          "pipeline_type": "search",
          "links": {},
          "far": 0.0007099999999999999,
          "far_lower": null,
          "far_upper": null,
          "far_unit": "1/yr",
          "far_meta": "na",
          "network_matched_filter_snr": 13.6,
          "network_matched_filter_snr_lower": null,
          "network_matched_filter_snr_upper": null,
          "network_matched_filter_snr_unit": "",
          "network_matched_filter_snr_meta": "na",
          "p_astro": 0.99,
          "p_astro_lower": null,
          "p_astro_upper": null,
          "p_astro_unit": "",
          "p_astro_meta": "na"
        }
      }
    }
  }
}