Event based logging

We can configure binary_c to output information about certain events. See [Notebook for events based logging](https://binary_c.gitlab.io/binary_c-python/examples/notebook_event_based_logging.html)

In the following subsections we describe the content of each of these event output logs.

Binary star system SN event (SN_BINARY) section

SN_BINARY events are events that capture a supernova occuring in a binary system. The log contains information about the pre-supernova state of the system, the post-supernova state of the system, and the natal velocity kick.

SN_BINARY event output log contents

Parameter	Description
uuid	Unique token associated with the system.
probability	Probability of the star system.
event_number	Event number to keep track of chronological order of events of this system. Count starts at 0.
event_type	Event type.
zams_mass_1	ZAMS mass of initially primary star. Unit: [\(\mathrm{M_{\odot}}\)].
zams_mass_2	ZAMS mass of initially secondary star. Unit: [\(\mathrm{M_{\odot}}\)].
zams_orbital_period	ZAMS period of the inner two binary stars. Unit: [\(\mathrm{yr}\)].
zams_separation	ZAMS separation of the inner two binary stars. Unit: [\(\mathrm{R_{\odot}}\)].
zams_eccentricity	ZAMS eccentricity of the inner two binary stars.
time	Time at which the event is logged. Unit: [\(\mathrm{Myr}\)].
metallicity	Metallicity of the star system.
random_seed	Random seed of the star system.
SN_post_SN_mass	Post supernova mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_post_SN_stellar_type	Post supernova stellar type of the star that went supernova.
SN_type	Supernova type.
SN_fallback_fraction	Fallback of initial supernova ejecta mass that falls back onto the remnant. based on Fryer 2012.
SN_fallback_mass	Mass of initial supernova ejecta mass that falls back onto the remnant. based on Fryer 2012. Unit: [\(\mathrm{M_{\odot}}\)].
SN_post_SN_ecc	Post-supernova eccentricity of the system.
SN_post_SN_orbital_period	Post-supernova orbital period of the system. Unit: [\(\mathrm{yr}\)].
SN_post_SN_separation	Post-supernova separation of the system. Unit: [\(\mathrm{R_{\odot}}\)].
SN_pre_SN_mass	Pre-supernova mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_stellar_type	Pre-supernova stellar type of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_radius	Pre-supernova radius of the star that went supernova. Unit: [\(\mathrm{R_{\odot}}\)].
SN_pre_SN_core_mass	Pre-supernova core mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_CO_core_mass	Pre-supernova CO core mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_He_core_mass	Pre-supernova He core mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_fraction_omega_crit	Pre-supernova fraction of critical rotation rate of the star that went supernova.
SN_pre_SN_ecc	Pre-supernova eccentricity of the system.
SN_pre_SN_orbital_period	Pre-supernova orbital period of the system. Unit: [\(\mathrm{yr}\)].
SN_pre_SN_separation	Pre-supernova separation of the system. Unit: [\(\mathrm{R_{\odot}}\)].
SN_pre_SN_companion_mass	Pre-supernova mass of the companion of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_companion_radius	Pre-supernova radius of the companion of the star that went supernova. Unit: [\(\mathrm{R_{\odot}}\)].
SN_pre_SN_companion_stellar_type	Pre-supernova stellar type of the companion of the star that went supernova.
SN_starnum	Star number of the star that went supernova.
SN_counter	Pre-supernova stellar type of the companion of the star that went supernova.
SN_kick_v	Supernova natal kick velocity. Unit: [\(\mathrm{km\,s^{-1}}\)].
SN_kick_omega	Supernova omega angle.
SN_kick_phi	Supernova phi angle.

Single star system SN event (SN_SINGLE) section

SN_SINGLE events are events that capture a supernova occuring in a single system. The log contains information about the pre-supernova state of the system, the post-supernova state of the system, and the natal velocity kick.

SN_SINGLE event output log contents

Parameter	Description
uuid	Unique token associated with the system.
probability	Probability of the star system.
event_number	Event number to keep track of chronological order of events of this system. Count starts at 0.
event_type	Event type.
zams_mass_1	ZAMS mass of initially primary star. Unit: [\(\mathrm{M_{\odot}}\)].
time	Time at which the event is logged. Unit: [\(\mathrm{Myr}\)].
metallicity	Metallicity of the star system.
random_seed	Random seed of the star system.
SN_post_SN_mass	Post supernova mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_post_SN_stellar_type	Post supernova stellar type of the star that went supernova.
SN_type	Supernova type.
SN_fallback_fraction	Fallback of initial supernova ejecta mass that falls back onto the remnant. based on Fryer 2012.
SN_fallback_mass	Mass of initial supernova ejecta mass that falls back onto the remnant. based on Fryer 2012. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_mass	Pre-supernova mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_stellar_type	Pre-supernova stellar type of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_radius	Pre-supernova radius of the star that went supernova. Unit: [\(\mathrm{R_{\odot}}\)].
SN_pre_SN_core_mass	Pre-supernova core mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_CO_core_mass	Pre-supernova CO core mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_He_core_mass	Pre-supernova He core mass of the star that went supernova. Unit: [\(\mathrm{M_{\odot}}\)].
SN_pre_SN_fraction_omega_crit	Pre-supernova fraction of critical rotation rate of the star that went supernova.
SN_starnum	Star number of the star that went supernova.
SN_counter	Pre-supernova stellar type of the companion of the star that went supernova.
SN_kick_v	Supernova natal kick velocity. Unit: [\(\mathrm{km\,s^{-1}}\)].
SN_kick_omega	Supernova omega angle.
SN_kick_phi	Supernova phi angle.

RLOF event (RLOF) section

RLOF events are events that capture RLOF episode in a binary system. The log contains information about the pre-RLOF state of the system, the post-RLOF state of the system, and some cumulative properties recorded during the RLOF.

RLOF event output log contents

Parameter	Description
uuid	Unique token associated with the system.
probability	Probability of the star system.
event_number	Event number to keep track of chronological order of events of this system. Count starts at 0.
event_type	Event type.
zams_mass_1	ZAMS mass of initially primary star. Unit: [\(\mathrm{M_{\odot}}\)].
zams_mass_2	ZAMS mass of initially secondary star. Unit: [\(\mathrm{M_{\odot}}\)].
zams_orbital_period	ZAMS period of the inner two binary stars. Unit: [\(\mathrm{yr}\)].
zams_separation	ZAMS separation of the inner two binary stars. Unit: [\(\mathrm{R_{\odot}}\)].
zams_eccentricity	ZAMS eccentricity of the inner two binary stars.
time	Time at which the event is logged. Unit: [\(\mathrm{Myr}\)].
metallicity	Metallicity of the star system.
random_seed	Random seed of the star system.
RLOF_initial_mass_accretor	Mass of the initial accretor star at the onset of RLOF. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_initial_mass_donor	Mass of the initial donor star at the onset of RLOF. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_initial_radius_accretor	Radius of the initial accretor star at the onset of RLOF. Unit: [\(\mathrm{R_{\odot}}\)].
RLOF_initial_radius_donor	Radius of the initial donor star at the onset of RLOF. Unit: [\(\mathrm{R_{\odot}}\)].
RLOF_initial_separation	Separation of the binary system at the onset of RLOF. Unit: [\(\mathrm{R_{\odot}}\)].
RLOF_initial_orbital_period	Orbital period of the binary system at the onset of RLOF. Unit: [\(\mathrm{yr}\)].
RLOF_initial_stellar_type_accretor	Stellar type of the initial accretor star at the onset of RLOF.
RLOF_initial_stellar_type_donor	Stellar type of the initial donor star at the onset of RLOF.
RLOF_initial_orbital_angular_momentum	Orbital angular momentum of the binary system at the onset of RLOF. Unit: [\(\mathrm{m}\)].
RLOF_initial_stability	Initial stability of the RLOF.
RLOF_initial_starnum_accretor	Star number of the initial accretor star at the onset of RLOF.
RLOF_initial_starnum_donor	Star number of the initial donor star at the onset of RLOF.
RLOF_initial_time	Time at the onset of RLOF. Unit: [\(\mathrm{yr}\)].
RLOF_initial_disk	Boolean of whether the mass transfer is through an accretion disk at the onset of RLOF.
RLOF_final_mass_accretor	Mass of the final accretor star at the end of RLOF. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_final_mass_donor	Mass of the final donor star at the end of RLOF. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_final_radius_accretor	Radius of the final accretor star at the end of RLOF. Unit: [\(\mathrm{R_{\odot}}\)].
RLOF_final_radius_donor	Radius of the final donor star at the end of RLOF. Unit: [\(\mathrm{R_{\odot}}\)].
RLOF_final_separation	Separation of the binary system at the end of RLOF. Unit: [\(\mathrm{R_{\odot}}\)].
RLOF_final_orbital_period	Orbital period of the binary system at the end of RLOF. Unit: [\(\mathrm{yr}\)].
RLOF_final_stellar_type_accretor	Stellar type of the final accretor star at the end of RLOF.
RLOF_final_stellar_type_donor	Stellar type of the final donor star at the end of RLOF.
RLOF_final_orbital_angular_momentum	Orbital angular momentum of the binary system at the end of RLOF. Unit: [\(\mathrm{m}\)].
RLOF_final_stability	Final stability of the RLOF.
RLOF_final_starnum_accretor	Star number of the final accretor star at the end of RLOF.
RLOF_final_starnum_donor	Star number of the final donor star at the end of RLOF.
RLOF_final_time	Time at the end of RLOF. Unit: [\(\mathrm{yr}\)].
RLOF_final_disk	Boolean of whether the mass transfer is through an accretion disk at the end of RLOF.
RLOF_total_mass_lost	Total mass lost from the system during the RLOF episode. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_total_mass_accreted	Total mass accreted onto the accretor during the RLOF episode. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_total_mass_transferred	Total mass transferred by the donor during the RLOF episode. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_total_mass_lost_from_accretor	Total mass lost from the accretor during the RLOF episode. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_total_mass_lost_from_common_envelope	Total mass lost from the system through common envelope ejection. Unit: [\(\mathrm{M_{\odot}}\)].
RLOF_total_time_spent_masstransfer	Duration of the RLOF episode. Unit: [\(\mathrm{yr}\)].
RLOF_episode_number	RLOF episode number.

DCO formation event (DCO_formation) section

DCO formation events are events capture the formation of a double compact object. If both stars are of stellar type between HeWD and BH the system logs the first step of that formation. The log contains information about the system upon DCO formation, the step before the DCO formation and the relevant GW times.

DCO_formation event output log contents

Parameter	Description
uuid	Unique token associated with the system.
probability	Probability of the star system.
event_number	Event number to keep track of chronological order of events of this system. Count starts at 0.
event_type	Event type.
zams_mass_1	ZAMS mass of initially primary star. Unit: [\(\mathrm{M_{\odot}}\)].
zams_mass_2	ZAMS mass of initially secondary star. Unit: [\(\mathrm{M_{\odot}}\)].
zams_orbital_period	ZAMS period of the inner two binary stars. Unit: [\(\mathrm{yr}\)].
zams_separation	ZAMS separation of the inner two binary stars. Unit: [\(\mathrm{R_{\odot}}\)].
zams_eccentricity	ZAMS eccentricity of the inner two binary stars.
time	Time at which the event is logged. Unit: [\(\mathrm{Myr}\)].
metallicity	Metallicity of the star system.
random_seed	Random seed of the star system.
DCO_stellar_type_1	Stellar type of the initially most massive star.
DCO_stellar_type_2	Stellar type of the initially second-most massive star.
DCO_mass_1	Mass of the initially most massive star. Unit: [\(\mathrm{M_{\odot}}\)].
DCO_mass_2	Mass of the initially second-most massive star. Unit: [\(\mathrm{yr}\)].
DCO_separation	Separation of the binary system. Unit: [\(\mathrm{R_{\odot}}\)].
DCO_eccentricity	Eccentricity of the binary system.
DCO_period	Period of the binary system. Unit: [\(\mathrm{yr}\)].
DCO_previous_separation	Separation of the binary system in the previous timestep. Unit: [\(\mathrm{R_{\odot}}\)].
DCO_previous_eccentricity	Eccentricity of the binary system in the previous timestep.
DCO_previous_period	Period of the binary system in the previous timestep. Unit: [\(\mathrm{yr}\)].
DCO_formation_time_in_years	Time from birth until the formation of the DCO. Unit: [\(\mathrm{yr}\)].
DCO_inspiral_time_in_years	Gravitational wave inspiral time of the DCO. Unit: [\(\mathrm{yr}\)].
DCO_merger_time_in_years	Total time from birth to merging of the DCO. Unit: [\(\mathrm{yr}\)].
DCO_total_rlof_episodes	Total number of RLOF episodes preceding the formation of the DCO.
DCO_stable_rlof_episodes	Total number of stable RLOF episodes preceding the formation of the DCO.
DCO_unstable_rlof_episodes	Total number of unstable RLOF episodes preceding the formation of the DCO.