Program option list and default values

Any program options that are not specified take default values.

  • On the command line, program options that are not explicitly specified default to the COMPAS default value for the option (as specified in the COMPAS code - may be sampled from a distribution).

  • On a grid file line, program options that are not explicitly specified default to the value specified for that option on the command line. If the program option was not explicitly specified on the command line, it will default to the COMPAS default value for the option, as described above. That is, the value for any option not specified on a grid file line option falls back to the value specified on the command line, which falls back to the COMPAS default if it was not specified on the command line.

The full list of program options with brief explanations and their default values is shown below. We also include a listing of options (this time, by name only) grouped by category.

Alphabetical listing: jump to A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Category listing: jump to Initial conditions Stellar evolution and winds Mass transfer physics Supernovae Administrative

COMPAS information

--help [ -h ]
Prints COMPAS help.

--version [ -v ]
Prints COMPAS version string.

Alphabetical listing

--add-options-to-sysparms
Add columns for program options to SSE System Parameters/BSE System Parameters file (mode dependent).
Options: { ALWAYS, GRID, NEVER }
Default = GRID

ALWAYS

indicates that the program options should be added to the sysparms file

GRID

indicates that the program options should be added to the sysparms file only if

a GRID file is specified, or RANGEs or SETs are specified for options

NEVER

indicates that the program options should not be added to the sysparms file

--allow-non-stripped-ECSN
Allow ECSNe in effectively single progenitors.
Default = FALSE

--allow-rlof-at-birth
Allow binaries that have one or both stars in RLOF at birth to evolve as over-contact systems.
Default = TRUE

--allow-touching-at-birth
Allow binaries that are touching at birth to be included in the sampling.
Default = FALSE

--angular-momentum-conservation-during-circularisation
Conserve angular momentum when binary is circularised when entering a Mass Transfer episode.
Default = FALSE

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--black-hole-kicks
Black hole kicks relative to NS kicks (not relevant for MANDELMUELLER --remnant-mass-prescription).
Options: { FULL, REDUCED, ZERO, FALLBACK }
Default = FALLBACK
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --black-hole-kicks-mode in future.

--black-hole-kicks-mode
Black hole kicks relative to NS kicks (not relevant for MANDELMUELLER --remnant-mass-prescription).
Options: { FULL, REDUCED, ZERO, FALLBACK }
Default = FALLBACK

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--case-bb-stability-prescription
Prescription for the stability of case BB/BC mass transfer.
Options: { ALWAYS_STABLE, ALWAYS_STABLE_ONTO_NSBH, TREAT_AS_OTHER_MT, ALWAYS_UNSTABLE }
Case BB mass transfer is treated as always stable, always stable only for mass transfer onto neutron stars or black holes, with stability as determined for all other mass transfer, or always unstable, respectively
Default = ALWAYS_STABLE

--check-photon-tiring-limit
Check the photon tiring limit is not exceeded during mass loss.
Default = FALSE

--chemically-homogeneous-evolution
Chemically Homogeneous Evolution mode. See [Riley et al., 2021] for details of the implementation of Chemically Homogeneous Evolution in COMPAS
Options: { NONE, OPTIMISTIC, PESSIMISTIC }
Default = PESSIMISTIC
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --chemically-homogeneous-evolution-mode in future.

--chemically-homogeneous-evolution-mode
Chemically Homogeneous Evolution mode. See [Riley et al., 2021] for details of the implementation of Chemically Homogeneous Evolution in COMPAS
Options: { NONE, OPTIMISTIC, PESSIMISTIC }
Default = PESSIMISTIC

--circulariseBinaryDuringMassTransfer
Circularise binary when it enters a Mass Transfer episode.
Default = TRUE

--common-envelope-allow-immediate-RLOF-post-CE-survive
Allow binaries that experience Roche lobe overflow immediately at the end of the CE phase to survive.
Default = FALSE

--common-envelope-allow-main-sequence-survive
Allow main sequence accretors to survive common envelope evolution if other criteria point to survival.
Default = TRUE

--common-envelope-allow-radiative-envelope-survive
Allow binaries with an evolved component with a radiative envelope to survive the common envelope phase (they always survive in the --common-envelope-formalism TWO_STAGE option).
Default = FALSE

--common-envelope-alpha
Common Envelope efficiency alpha.
Default = 1.0

--common-envelope-alpha-thermal
Thermal energy contribution to the total envelope binding energy.
Defined such that \(\lambda = \alpha_{th} \times \lambda_{b} + (1.0 - \alpha_{th}) \times \lambda_{g}\).
Default = 1.0

--common-envelope-formalism
CE formalism prescription.
Options: { ENERGY, TWO_STAGE }
ENERGY is the standard alpha-lambda formalism; TWO_STAGE is the formalism of Hirai & Mandel (2022) -- the latter always allows radiative-envelope donors to survive CE, so --common-envelope-allow-radiative-envelope-survive option is ignored
Default = ENERGY

--common-envelope-lambda
Common Envelope lambda.
Only used when --common-envelope-lambda-prescription = LAMBDA_FIXED.
Default = 0.1

--common-envelope-lambda-multiplier
Multiplicative constant to be applied to the common envelope lambda parameter for any prescription.
Default = 1.0

--common-envelope-lambda-nanjing-enhanced
Continuous extrapolation beyond maximum radius range in Nanjing lambda's as implemented in StarTrack. Only used when --common-envelope-lambda-prescription = LAMBDA_NANJING.
Default = FALSE

--common-envelope-lambda-nanjing-interpolate-in-mass
Interpolate Nanjing lambda parameters across different mass models. Only used when --common-envelope-lambda-prescription = LAMBDA_NANJING.
Default = FALSE

--common-envelope-lambda-nanjing-interpolate-in-metallicity
Interpolate Nanjing lambda parameters across population I and population II metallicity models. Only used when --common-envelope-lambda-prescription = LAMBDA_NANJING.
Default = FALSE

--common-envelope-lambda-nanjing-use_rejuvenated-mass
Use rejuvenated or effective ZAMS mass instead of true birth mass when computing Nanjing lambda parameters. Only used when --common-envelope-lambda-prescription = LAMBDA_NANJING.
Default = FALSE

--common-envelope-lambda-prescription
CE lambda (envelope binding energy) prescription.
Options: { LAMBDA_FIXED, LAMBDA_LOVERIDGE, LAMBDA_NANJING, LAMBDA_KRUCKOW, LAMBDA_DEWI }
LAMBDA_FIXED is a constant; LAMBDA_LOVERIDGE is the prescription from Loveridge et al., 2011; LAMBDA_NANJING is from Xu & Li, 2010; LAMBDA_KRUCKOW is from Kruckow et al., 2016; and LAMBDA_DEWI is the fit from Appendix A in Claeys et al. 2014, based on Dewi & Tauris 2000
Default = LAMBDA_NANJING

--common-envelope-mass-accretion-constant
Value of mass accreted by NS/BH during common envelope evolution if assuming all NS/BH accrete same amount of mass.
Used when --common-envelope-mass-accretion-prescription = CONSTANT, ignored otherwise.
Default = 0.0

--common-envelope-mass-accretion-max
Maximum amount of mass accreted by NS/BHs during common envelope evolution (\(M_\odot\)).
Default = 0.1

--common-envelope-mass-accretion-min
Minimum amount of mass accreted by NS/BHs during common envelope evolution (\(M_\odot\)).
Default = 0.04

--common-envelope-mass-accretion-prescription
Assumption about whether NS/BHs can accrete mass during common envelope evolution.
ZERO is no accretion; CONSTANT means a fixed amount of accretion determined by --common-envelope-mass-accretion-constant; UNIFORM means a uniform random draw between --common-envelope-mass-accretion-min and --common-envelope-mass-accretion-max (Oslowski et al., 2011);, MACLEOD follows the prescription of MacLeod et al., 2015, and CHEVALIER follows the accretion assumptions in Chevalier et al. 1993 as in Model 2 from van Son et al. 2020
Options: { ZERO, CONSTANT, UNIFORM, MACLEOD, CHEVALIER }
Default = ZERO

--common-envelope-recombination-energy-density
Recombination energy density (erg g−1).
Default = \(1.5 \times 10^{13}\)

--common-envelope-slope-kruckow
Slope for the Kruckow lambda (see Kruckow et al. 2016 as implemented by Vigna-Gomez et al. 2018).
Default = −0.833333

--convective-envelope-temperature-threshold
Temperature [K] threshold, below which the envelopes of giants are convective. Only used for --envelope-state-prescription = FIXED_TEMPERATURE, ignored otherwise.
Default = 5370

--cool-wind-mass-loss-multiplier
Multiplicative constant for wind mass loss of cool stars, i.e. those with temperatures below the VINK_MASS_LOSS_MINIMUM_TEMP (default 12500K).
Only applicable when --mass-loss-prescription = VINK.
Default = 1.0

--create-YAML-file
Creates new YAML file. Argument is filename for new YAML file.
Default = None - name must be supplied if option is present.

--critical-mass-ratio-HG-degenerate-accretor
Critical mass ratio for MT from a HG star to a degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.21

--critical-mass-ratio-HG-non-degenerate-accretor
Critical mass ratio for MT from a HG star to a non-degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.25

--critical-mass-ratio-MS-high-mass-degenerate-accretor
Critical mass ratio for MT from a MS star to a degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.0

--critical-mass-ratio-MS-high-mass-non-degenerate-accretor
Critical mass ratio for MT from a MS star to a non-degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.625

--critical-mass-ratio-MS-low-mass-degenerate-accretor
Critical mass ratio for MT from a MS star to a degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 1.0

--critical-mass-ratio-MS-low-mass-non-degenerate-accretor
Critical mass ratio for MT from a MS star to a non-degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 1.44

--critical-mass-ratio-giant-degenerate-accretor
Critical mass ratio for MT from a giant star to a degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.87

--critical-mass-ratio-giant-non-degenerate-accretor
Critical mass ratio for MT from a giant star to a non-degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default shows -1, but this translates to a function of the core mass ratio, as described in Claeys+ 2014.

--critical-mass-ratio-helium-HG-degenerate-accretor
Critical mass ratio for MT from a helium HG star to a degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.21

--critical-mass-ratio-helium-HG-non-degenerate-accretor
Critical mass ratio for MT from a helium HG star to a non-degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.25

--critical-mass-ratio-helium-MS-degenerate-accretor
Critical mass ratio for MT from a helium MS star to a degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.0

--critical-mass-ratio-helium-MS-non-degenerate-accretor
Critical mass ratio for MT from a helium MS star to a non-degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.0

--critical-mass-ratio-helium-giant-degenerate-accretor
Critical mass ratio for MT from a helium giant star to a degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.87

--critical-mass-ratio-helium-giant-non-degenerate-accretor
Critical mass ratio for MT from a helium giant star to a non-degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 1.28

--critical-mass-ratio-prescription
Critical mass ratio stability prescription (if any).
Options: { NONE, ZERO, CLAEYS, GE20, GE20_IC, HURLEY_HJELLMING_WEBBINK }
NONE defaults to the zeta prescription for stability.
CLAEYS uses qCrit values from Claeys et al. 2014.
GE20 uses qCrit values from Ge et al. 2020 (adiabatic assumption).
GE20_IC uses qCrit values from Ge et al. 2020 (isentropic envelope assumption).
HURLEY_HJELLMING_WEBBINK uses qCrit values from Hurley et al. 2002 (Hjellming & Webbink 1987 for mass transfer from a giant primary).
Warning: if running with --critical-mass-ratio-prescription, zetas will not be computed, so should not be trusted in the outputs.
Default = NONE

--critical-mass-ratio-white-dwarf-degenerate-accretor
Critical mass ratio for MT from a white dwarf to a degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 1.6

--critical-mass-ratio-white-dwarf-non-degenerate-accretor
Critical mass ratio for MT from a white dwarf to a non-degenerate accretor.
0 is always stable, < 0 is disabled.
Only used for --critical-mass-ratio-prescription CLAEYS, ignored otherwise.
Default = 0.0

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--debug-classes
Developer-defined debug classes to enable (vector).
Default = All debug classes enabled (e.g. no filtering)

--debug-level
Determines which print statements are displayed for debugging.
Default = 0

--debug-to-file
Write debug statements to file.
Default = FALSE

--detailed-output
Print BSE detailed information to file.
Default = FALSE

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--eccentricity [ -e ]
Initial eccentricity for a binary star when evolving in BSE mode. Default = 0.0

--eccentricity-distribution
Initial eccentricity distribution.
Options: { ZERO, FLAT, GELLER+2013, THERMAL, DUQUENNOYMAYOR1991, SANA2012 }
ZERO always circular, FLAT is uniform on [--eccentricity-min,``--eccentricity-max``], THERMAL is p(e) proportional to e, and the other options refer to the distributions of Geller et al. 2013, Duqennoy & Mayor 1991, and Sana et al. 2012.
Default = ZERO

--eccentricity-max
Maximum eccentricity to generate.
Default = 1.0

--eccentricity-min
Minimum eccentricity to generate.
Default = 0.0

--eddington-accretion-factor
Multiplication factor for Eddington accretion for NS & BH (i.e. > 1 is super-eddington and 0 is no accretion).
Default = 1.0

--emit-gravitational-radiation
Emit gravitational radiation at each timestep of binary evolution according to Peters 1964.
Default = FALSE

--enable-warnings
Display warning messages to stdout.
Default = FALSE

--enable-rotationally-enhanced-mass-loss
Enable rotationally enhanced mass loss for rapidly rotating stars following Langer (1998) Default = FALSE

--enhance-CHE-lifetimes-luminosities
Enhance lifetimes and luminosities of CH stars using a fit to detailed models from Szecsi et al. (2015) Default = FALSE

--envelope-state-prescription
Prescription for determining whether the envelope of the star is convective or radiative.
Options: { LEGACY, HURLEY, FIXED_TEMPERATURE }
LEGACY refers to the model used in Stevenson et al., 2017
HURLEY refers to the model of Hurley, Pols, Tout, 2002
FIXED_TEMPERATURE assumes that a deep convective envelope developes only when the temperature drops below CONVECTIVE_BOUNDARY_TEMPERATURE (Klencki et al., 2020)
Default = LEGACY

--errors-to-file
Write error messages to file.
Default = FALSE

--expel-convective-envelope-above-luminosity-threshold
Expel convective envelope in a pulsation if the luminosity to mass ratio exceeds the threshold given by --luminosity-to-mass-threshold
Default = FALSE

--evolve-double-white-dwarfs
Continue evolving double white dwarf systems after their formation.
Default = FALSE

--evolve-main-sequence-mergers
Continue evolving the remnant after a main sequence merger.
Default = FALSE

--evolve-pulsars
Evolve pulsar properties of Neutron Stars.
Default = FALSE

--evolve-unbound-systems
Continue evolving stars even if the binary is disrupted.
Default = TRUE

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--fix-dimensionless-kick-magnitude
Fix dimensionless kick magnitude to this value.
Default = n/a (not used if option not present)

--fp-error-mode
Specifies the floating-point error handling mode.
Options: { OFF, ON, DEBUG }
Default = OFF
Refer to Handling COMPAS errors for a discussion of the option values.

--fryer-supernova-engine
Supernova engine type if using the remnant mass prescription from [Fryer et al., 2012].
Options: { DELAYED, RAPID }
Default = DELAYED

--fryer-22-fmix
Parameter describing the mixing growth time when using the 'FRYER2022' remnant mass distribution [Fryer et al., 2022].
Default = 0.5, which is closest to the 'DELAYED' remnant mass prescription from [Fryer et al., 2012].
A value of 4.0 is closest to the 'RAPID' remnant mass prescription from [Fryer et al., 2012].
If the FALLBACK option is used for the kicks, then the proto core masses will be determined by the fryer-supernova-engine option.

--fryer-22-mcrit
Critical CO core mass for black hole formation when using the 'FRYER2022' remnant mass distribution [Fryer et al., 2022].
Default = 5.75

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--grid
Grid filename. (See Grid files)
Default = ’’ (None)

--grid-lines-to-process
The number of grid file lines to be processed.
Default = Process to EOF

--grid-start-line
The first line of the grid file to be processed.
Default = 0

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--hdf5-buffer-size
The HDF5 IO buffer size for writing to HDF5 logfiles (number of HDF5 chunks).
Default = 1

--hdf5-chunk-size
The HDF5 dataset chunk size to be used when creating HDF5 logfiles (number of logfile entries).
Default = 100000

--help [ -h ]
Prints COMPAS help (-h is short form, --help includes more information).

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--include-WD-binaries-as-DCO
When enabled, changes the definition of "Double Compact Object" from a binary comprised of any two of {Neutron Star, Black Hole}
to a binary star comprised of any two of {Helium White Dwarf, Carbon-Oxygen White Dwarf, Oxygen-Neon White Dwarf, Neutron Star, Black Hole}.
Default = FALSE

--initial-mass
Initial mass for a single star when evolving in SSE mode (\(M_\odot\)).
Default = Sampled from IMF

--initial-mass-1
Initial mass for the primary star when evolving in BSE mode (\(M_\odot\)).
Default = Sampled from IMF

--initial-mass-2
Initial mass for the secondary star when evolving in BSE mode (\(M_\odot\)).
Default = Sampled from IMF

--initial-mass-function [ -i ]
Initial mass function.
Options: { SALPETER, POWERLAW, UNIFORM, KROUPA }
SALPETER and KROUPA use the IMFs of Salpeter 1955 and Kroupa 2001
POWERLAW samples from a single power law with slope --initial-mass-power
UNIFORM samples uniformly between --initial-mass-min and --initial-mass-min
Default = KROUPA

--initial-mass-max
Maximum mass to generate using given IMF (\(M_\odot\)).
Default = 150.0

--initial-mass-min
Minimum mass to generate using given IMF (\(M_\odot\)).
Default = 5.0

--initial-mass-power
Single power law power to generate primary mass using POWERLAW IMF.
Default = 0.0

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--kick-direction
Natal kick direction distribution.
Options: { ISOTROPIC, INPLANE, PERPENDICULAR, POWERLAW, WEDGE, POLES }
Kick angles are defined relative to the spin axis.
INPLANE and PERPENDICULAR are strictly in the equatorial plane or in polar directions.
WEDGE and POLES are preferentially but exactly in the equatorial plane or in polar directions with 1 degree scales, respectively.
POWERLAW quantifies the preference for polar vs planar kicks with the --kick-direction-power parameter.
Default = ISOTROPIC
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --kick-direction-distribution in future.

--kick-direction-distribution
Natal kick direction distribution.
Options: { ISOTROPIC, INPLANE, PERPENDICULAR, POWERLAW, WEDGE, POLES }
Kick angles are defined relative to the spin axis.
INPLANE and PERPENDICULAR are strictly in the equatorial plane or in polar directions.
WEDGE and POLES are preferentially but exactly in the equatorial plane or in polar directions with 1 degree scales, respectively.
POWERLAW quantifies the preference for polar vs planar kicks with the --kick-direction-power parameter.
Default = ISOTROPIC

--kick-direction-power
Power for power law kick direction distribution, where 0.0 = isotropic, +ve = polar, -ve = in plane.
Default = 0.0 (isotropic)

--kick-magnitude
Value to be used as the (drawn) kick magnitude for a single star when evolving in SSE mode, should the star undergo a supernova event (\(km s^{−1}\)).
If a value for option --kick-magnitude-random is specified, it will be used in preference to --kick-magnitude.
Default = 0.0

--kick-magnitude-1
Value to be used as the (drawn) kick magnitude for the primary star of a binary system when evolving in BSE mode, should the star undergo a supernova event (\(km s^{−1}\)).
If a value for option --kick-magnitude-random-1 is specified, it will be used in preference to --kick-magnitude-1.
Default = 0.0

--kick-magnitude-2
Value to be used as the (drawn) kick magnitude for the secondary star of a binary system when evolving in BSE mode, should the star undergo a supernova event (\(km s^{−1}\)).
If a value for option --kick-magnitude-random-2 is specified, it will be used in preference to --kick-magnitude-2.
Default = 0.0

--kick-magnitude-distribution
Natal kick magnitude distribution.
Options: { ZERO, FIXED, FLAT, MAXWELLIAN, BRAYELDRIDGE, MULLER2016, MULLER2016MAXWELLIAN, MULLERMANDEL }
ZERO assigns kick magnitudes of 0.0.
FIXED always sets the magnitude to a fixed value based on supernova type.
FLAT and MAXWELLIAN draw kicks from uniform or Maxwellian (e.g., Hobbs et al., 2005) distributions, respectively.
BRAYELDRIDGE and MULLERMANDEL use momentum-preserving kicks from Bray & Eldrigde 2018 and Mandel & Mueller 2020, respectively.
MULLER2016 and MULLER2016MAXWELLIAN use kicks from Mueller 2016 as implemented in Vigna-Gomez et al., 2018
(reduced by a factor of sqrt(3) in the latter case).
Note that this is independent from --remnant-mass-prescription to provide flexibility; however, the MULLERMANDEL
kick prescription is intended to be consistently used with the MULLERMANDEL remnant mass prescription,
as well as with the MALTSEV2024 remnant mass prescription.
Default = MULLERMANDEL

--kick-magnitude-max
Maximum drawn kick magnitude (\(km s^{−1}\)).
Must be > 0 if using --kick-magnitude-distribution = FLAT.
Default = −1.0

--kick-magnitude-random
CDF value to be used to draw the kick magnitude for a single star when evolving in SSE mode, should the star undergo a supernova event and should the chosen distribution sample from a cumulative distribution function.
Must be a floating-point number in the range \([0.0, 1.0)\).
The specified value for this option will be used in preference to any specified value for --kick-magnitude.
Default = Random number drawn uniformly from \([0.0, 1.0)\)

--kick-magnitude-random-1
CDF value to be used to draw the kick magnitude for the primary star of a binary system when evolving in BSE mode, should the star undergo a supernova event and should the chosen distribution sample from a cumulative distribution function.
Must be a floating-point number in the range \([0.0, 1.0)\).
The specified value for this option will be used in preference to any specified value for --kick-magnitude-1.
Default = Random number drawn uniformly from \([0.0, 1.0)\)

--kick-magnitude-random-2
CDF value to be used to draw the kick magnitude for the secondary star of a binary system when evolving in BSE mode, should the star undergo a supernova event and should the chosen distribution sample from a cumulative distribution function.
Must be a floating-point number in the range \([0.0, 1.0)\).
The specified value for this option will be used in preference to any specified value for --kick-magnitude-2.
Default = Random number drawn uniformly from \([0.0, 1.0)\)

--kick-magnitude-sigma-CCSN-BH
Sigma for chosen kick magnitude distribution for black holes (\(km s^{−1}\)).
Ignored if not needed for the chosen kick magnitude distribution.
Default = 265.0

--kick-magnitude-sigma-CCSN-NS
Sigma for chosen kick magnitude distribution for neutron stars (\(km s^{−1}\)).
Ignored if not needed for the chosen kick magnitude distribution.
Default = 265.0

--kick-magnitude-sigma-ECSN
Sigma for chosen kick magnitude distribution for ECSN (\(km s^{−1}\)).
Ignored if not needed for the chosen kick magnitude distribution.
Default = 30.0

--kick-magnitude-sigma-USSN
Sigma for chosen kick magnitude distribution for USSN (\(km s^{−1}\)).
Ignored if not needed for the chosen kick magnitude distribution.
Default = 30.0

--kick-mean-anomaly-1
The mean anomaly at the instant of the supernova for the primary star of a binary system when evolving in BSE mode, should it undergo a supernova event.
Must be a floating-point number in the range \([0.0, 2\pi)\).
Default = Random number drawn uniformly from \([0.0, 2\pi)\)

--kick-mean-anomaly-2
The mean anomaly at the instant of the supernova for the secondary star of a binary system when evolving in BSE mode, should it undergo a supernova event.
Must be a floating-point number in the range \([0.0, 2\pi)\).
Default = Random number drawn uniformly from \([0.0, 2\pi)\)

--kick-phi-1
The angle between ’x’ and ’y’, both in the orbital plane of the supernova vector, for the primary star of a binary system when evolving in BSE mode, should it undergo a supernova event (radians).
Default = Drawn according to specified --kick-direction distribution

--kick-phi-2
The angle between ’x’ and ’y’, both in the orbital plane of the supernova vector, for the secondary star of a binary system when evolving in BSE mode, should it undergo a supernova event (radians).
Default = Drawn according to specified --kick-direction distribution

--kick-scaling-factor
Arbitrary factor used to scale kicks.
Default = 1.0

--kick-theta-1
The angle between the orbital plane and the ’z’ axis of the supernova vector for the primary star of a binary system when evolving in BSE mode, should it undergo a supernova event (radians).
Default = Drawn according to specified --kick-direction distribution

--kick-theta-2
The angle between the orbital plane and the ’z’ axis of the supernova vector for the secondary star of a binary system when evolving in BSE mode, should it undergo a supernova event (radians).
Default = Drawn according to specified --kick-direction distribution

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--LBV-mass-loss-prescription
Luminous blue variable mass loss prescription.
Options: { NONE, ZERO, HURLEY, HURLEY_ADD, BELCZYNSKI }
NONE : No LBV winds
ZERO : No LBV winds
HURLEY : Hurley, Pols, Tout (2000)
HURLEY_ADD : HURLEY in addition to other winds
BELCZYNSKI : Belzcynski et al. 2010
Default = HURLEY_ADD
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

--log-classes
Logging classes to be enabled (vector).
Default = All debug classes enabled (e.g. no filtering)

--logfile-common-envelopes
Filename for Common Envelopes logfile (BSE mode).
Default = ’BSE_Common_Envelopes’

--logfile-common-envelopes-record-types
Enabled record types for Common Envelopes logfile (BSE mode).
Default = -1 (all record types)

--logfile-definitions
Filename for logfile record definitions file.
Default = ’’ (None)

--logfile-detailed-output
Filename for the Detailed Output logfile.
Default = ’SSE_Detailed_Output’ for SSE mode; ’BSE_Detailed_Output’ for BSE mode

--logfile-detailed-output-record-types
Enabled record types for the Detailed Output logfile.
Default = -1 (all record types)

--logfile-double-compact-objects
Filename for the Double Compact Objects logfile (BSE mode).
Default = ’BSE_Double_Compact_Objects’

--logfile-double-compact-objects-record-types
Enabled record types for the Double Compact Objects logfile (BSE mode).
Default = -1 (all record types)

--logfile-name-prefix
Prefix for logfile names.
Default = ’’ (None)

--logfile-pulsar-evolution
Filename for the Pulsar Evolution logfile (BSE mode).
Default = ’BSE_Pulsar_Evolution’

--logfile-pulsar-evolution-record-types
Enabled record types for the Pulsar Evolution logfile (BSE mode).
Default = -1 (all record types)

--logfile-rlof-parameters
Filename for the RLOF Printing logfile (BSE mode).
Default = ’BSE_RLOF’

--logfile-rlof-parameters-record-types
Enabled record types for the RLOF Printing logfile (BSE mode).
Default = -1 (all record types)

--logfile-supernovae
Filename for the Supernovae logfile.
Default = ’SSE_Supernovae’ for SSE mode; ’BSE_Supernovae’ for BSE mode

--logfile-supernovae-record-types
Enabled record types for the Supernovae logfile.
Default = -1 (all record types)

--logfile-switch-log
Filename for the Switch Log logfile.
Default = ’SSE_Switch_Log’ for SSE mode; ’BSE_Switch_Log’ for BSE mode

--logfile-system-parameters
Filename for the System Parameters logfile (BSE mode).
Default = ’SSE_System_Parameters’ for SSE mode; ’BSE_System_Parameters’ for BSE mode

--logfile-system-parameters-record-types
Enabled record types for the System Parameters logfile (BSE mode).
Default = -1 (all record types)

--logfile-type
The type of logfile to be produced by COMPAS. Options are: HDF5, CSV, TSV, TXT.
Default = ’HDF5’

--log-level
Determines which print statements are included in the logfile.
Default = 0

--luminous-blue-variable-multiplier
Multiplicative constant for LBV mass loss. (Use 10 for Mennekens & Vanbeveren (2014)).
Note that wind mass loss will also be multiplied by the --overall-wind-mass-loss-multiplier.
Default = 1.5

--luminous-blue-variable-prescription
Luminous blue variable mass loss prescription.
Options: { NONE, ZERO, HURLEY, HURLEY_ADD, BELCZYNSKI }
NONE : No LBV winds
ZERO : No LBV winds
HURLEY : Hurley, Pols, Tout (2000) LBV winds only for LBV stars
HURLEY_ADD : HURLEY in addition to other winds
BELCZYNSKI : Belzcynski et al. 2010
Default = HURLEY_ADD
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --LBV-mass-loss-prescription in future.
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

--luminosity-to-mass-threshold
Threshold \(\log_{10}(Luminosity/Mass)\) (in solar units) above which, if the option expel-convective-envelope-above-luminosity-threshold is set to TRUE, pulsations eject the convective envelope
Default = 4.2

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--mass-change-fraction
Approximate desired fractional change in stellar mass on phase when setting SSE and BSE timesteps (applied before --timestep--multiplier).
Recommended value is 0.005.
A value of 0.0 means that this choice is ignored, and timestep estimates will be calculated by COMPAS.
Default = 0.0

--mass-loss-prescription
Mass loss prescription.
Options: { ZERO, NONE, HURLEY, BELCZYNSKI2010, MERRITT2024 }
ZERO/NONE : No wind mass loss
HURLEY : Mass loss according to Hurley (2000)
BELCZYNSKI2010: Mass loss as per Belczynski (2010), and the default prior to 2023
MERRITT2024 : Flexible mass loss with phase specific options: (OB, RSG, WR, VMS)
Default = MERRITT2024
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

--mass-ratio [ -q ]
Mass ratio \(\frac{m2}{m1}\) used to determine secondary mass if not specified via --initial-mass-2.
Default: value is sampled if option not specified.

--mass-ratio-distribution
Initial mass ratio distribution for \(q = \frac{m2}{m1}\).
Options: { FLAT, DUQUENNOYMAYOR1991, SANA2012 }
FLAT is uniform in the mass ratio between --mass-ratio-min and --mass-ratio-max.
Other prescriptions follow Duquennoy & Mayor 1991 and Sana et al. 2012
Default = FLAT

--mass-ratio-max
Maximum mass ratio \(\frac{m2}{m1}\) to generate.
Default = 1.0

--mass-ratio-min
Minimum mass ratio \(\frac{m2}{m1}\) to generate.
Default = 0.01

--mass-transfer
Enable mass transfer.
Default = TRUE
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --use-mass-transfer in future.

--mass-transfer-accretion-efficiency-prescription
Mass transfer accretion efficiency prescription.
Options: { THERMAL, FIXED }
Default = THERMAL

--mass-transfer-angular-momentum-loss-prescription
Mass Transfer Angular Momentum Loss prescription.
Options: { JEANS, ISOTROPIC, CIRCUMBINARY, MACLEOD_LINEAR, ARBITRARY }
Default = ISOTROPIC

--mass-transfer-fa
Mass Transfer fraction accreted.
Used when --mass-transfer-accretion-efficiency-prescription = FIXED_FRACTION.
Default = 0.5

--mass-transfer-jloss
Specific angular momentum with which the non-accreted system leaves the system.
Used when --mass-transfer-angular-momentum-loss-prescription = ARBITRARY, ignored otherwise.
Default = 1.0

--mass-transfer-jloss-macleod-linear-fraction-degen
Specific angular momentum interpolation fraction for degenerate accretors, linear between 0 and 1 corresponding to the accretor and L2 point.
Used when --mass-transfer-angular-momentum-loss-prescription = MACLEOD_LINEAR, ignored otherwise.
Default = 0.5

--mass-transfer-jloss-macleod-linear-fraction-non-degen
Specific angular momentum interpolation fraction for non-degenerate accretors, linear between 0 and 1 corresponding to the accretor and L2 point.
Used when --mass-transfer-angular-momentum-loss-prescription = MACLEOD_LINEAR, ignored otherwise.
Default = 0.5

--mass-transfer-rejuvenation-prescription
Mass Transfer Rejuvenation prescription.
Options: { HURLEY, STARTRACK }
HURLEY uses the Hurley, Pols, Tout (2000) model.
STARTRACK uses the model from Belczynski et al. 2008
Default = STARTRACK

--mass-transfer-thermal-limit-accretor
Mass Transfer Thermal Accretion limit multiplier.
Options: { CFACTOR, ROCHELOBE }
Default = CFACTOR
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --mass-transfer-thermal-limit-accretor-multiplier in future.

--mass-transfer-thermal-limit-accretor-multiplier
Mass Transfer Thermal Accretion limit multiplier.
Options: { CFACTOR, ROCHELOBE }
Default = CFACTOR

--mass-transfer-thermal-limit-C
Mass Transfer Thermal rate factor for the accretor.
Default = 10.0

--maximum-evolution-time
Maximum time to evolve binaries (Myr). Evolution of the binary will stop if this number is reached.
Default = 13700.0

--maximum-mass-donor-nandez-ivanova
Maximum donor mass allowed for the revised common envelope formalism of Nandez & Ivanova (\(M_\odot\)).
Default = 2.0

--maximum-neutron-star-mass
Maximum mass of a neutron star (\(M_\odot\)).
Default = 2.5

--maximum-number-timestep-iterations
Maximum number of timesteps to evolve binary. Evolution of the binary will stop if this number is reached.
Default = 99999

--mcbur1
Minimum core mass at base of AGB to avoid fully degenerate CO core formation (\(M_\odot\)).
e.g. 1.6 in [Hurley et al., 2000] presciption; 1.83 in [Fryer et al., 2012] and Belczynski et al. (2008) models.
Default = 1.6

--metallicity [ -z ]
Metallicity.
The value specified for metallicity is applied to both stars for BSE mode.
Default = 0.0142

--metallicity-distribution
Metallicity distribution.
Options: { ZSOLAR, LOGUNIFORM }
ZSOLAR uses ZSOL_ASPLUND for all initial metallicities.
LOGUNIFORM draws the metallicity uniformly in the log between --metallicity-min and --metallicity-max
Default = ZSOLAR

--metallicity-max
Maximum metallicity to generate.
Default = 0.03

--metallicity-min
Minimum metallicity to generate.
Default = 0.0001

--minimum-secondary-mass
Minimum mass of secondary to generate (\(M_\odot\)).
Defaults to 0.1 if --initial-mass-2 is specified, otherwise value of --initial-mass-min.

--mode
The mode of evolution.
Options: { SSE, BSE }
Default = BSE

--muller-mandel-kick-multiplier-BH
Scaling prefactor for BH kicks when using the MULLERMANDEL kick magnitude distribution
Default = 200.0

--muller-mandel-kick-multiplier-NS
Scaling prefactor for NS kicks when using the MULLERMANDEL kick magnitude distribution
Default = 520.0

--muller-mandel-sigma-kick
Scatter width for NS and BH kicks when using the MULLERMANDEL kick magnitude distribution
Default = 0.3

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--natal-kick-for-PPISN TRUE indicates PPISN remnants will receive natal kicks via the same prescription as CCSN remnants.
FALSE indicates PPISN remnants will receive no natal kicks.
Default = TRUE

--neutrino-mass-loss-BH-formation
Assumption about neutrino mass loss during BH formation (works with FRYER2012 or FRYER2022 --remnant-mass-prescription, but not MANDELMUELLER).
Options: { FIXED_FRACTION, FIXED_MASS }
Default = FIXED_MASS

--neutrino-mass-loss-BH-formation-value
Amount of mass lost in neutrinos during BH formation (either as fraction or in solar masses, depending on the value of --neutrino-mass-loss-bh-formation).
Default = 0.1

--neutron-star-equation-of-state
Neutron star equation of state.
Options: { SSE, ARP3 }
Default = SSE

--notes
Annotation strings (vector).
Default = ""

--notes-hdrs
Annotations header strings (vector).
Default = No annotations

--number-of-systems [ -n ]
The number of systems to simulate.
Single stars for SSE mode; binary stars for BSE mode.
This option is ignored if either of the following is true:

  • the user specified a grid file

  • the user specified a range or set for any options - this implies a grid

In both cases the number of objects evolved will be the number specified by the grid.
Default = 10

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--OB-mass-loss
Main sequence mass loss prescription.
Options: { NONE, ZERO, VINK2001, VINK2021, BJORKLUND2022, KRTICKA2018 }
NONE/ZERO turns off mass loss for main sequence stars.|br| Default = VINK2021
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --OB-mass-loss-prescription in future.
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

--OB-mass-loss-prescription
Main sequence mass loss prescription.
Options: { NONE, ZERO, VINK2001, VINK2021, BJORKLUND2022, KRTICKA2018 }
NONE/ZERO turns off mass loss for main sequence stars.|br| Default = VINK2021
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

--orbital-period
Initial orbital period for a binary star when evolving in BSE mode (days).
Used only if the semi-major axis is not specified via --semi-major-axis.
Default: value is sampled if option not specified.

--orbital-period-distribution
Initial orbital period distribution.
Options: { FLATINLOG }
Default = FLATINLOG

--orbital-period-max
Maximum period to generate (days).
Default = 1000.0

--orbital-period-min
Minimum period to generate (days).
Default = 1.1

--output-container [ -c ]
Container (directory) name for output files.
Default = ’COMPAS_Output’

--output-path [ -o ]
Path to which output is saved (i.e. directory in which the output container is created).
Default = Current working directory (CWD)

--overall-wind-mass-loss-multiplier
Multiplicative constant for overall wind mass loss.
Note that this multiplication factor is applied after the luminous-blue-variable-multiplier, the wolf-rayet-multiplier, and the cool-wind-mass-loss-multiplier.
Default = 1.0

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--pair-instability-supernovae
Enable pair instability supernovae (PISN).
Default = TRUE

--PISN-lower-limit
Minimum core mass for PISN (\(M_\odot\)).
Default = 60.0

--PISN-upper-limit
Maximum core mass for PISN (\(M_\odot\)).
Default = 135.0

--population-data-printing
Print details of population.
Default = FALSE

--PPI-CO-Core-Shift-Hendriks
Shift in CO core mass for PPI (in Msol) for the Hendriks+23 PPI prescription Default = 0.0

--PPI-lower-limit
Minimum core mass for PPI (\(M_\odot\)).
Default = 35.0

--PPI-upper-limit
Maximum core mass for PPI (\(M_\odot\)).
Default = 60.0

--print-bool-as-string
Print boolean properties as ’TRUE’ or ’FALSE’.
Default = FALSE

--pulsar-birth-magnetic-field-distribution
Pulsar birth magnetic field distribution.
Options: { ZERO, FLATINLOG, UNIFORM, LOGNORMAL }
Default = ZERO

--pulsar-birth-magnetic-field-distribution-max
Maximum (\(log_{10}\)) pulsar birth magnetic field.
Default = 13.0

--pulsar-birth-magnetic-field-distribution-min
Minimum (\(log_{10}\)) pulsar birth magnetic field.
Default = 11.0

--pulsar-birth-spin-period-distribution
Pulsar birth spin period distribution.
Options: { ZERO, UNIFORM, NORMAL }
Default = ZERO

--pulsar-birth-spin-period-distribution-max
Maximum pulsar birth spin period (ms).
Default = 100.0

--pulsar-birth-spin-period-distribution-min
Minimum pulsar birth spin period (ms).
Default = 10.0

--pulsar-magnetic-field-decay-massscale
Mass scale on which magnetic field decays during accretion (\(M_\odot\)).
Default = 0.025

--pulsar-magnetic-field-decay-timescale
Timescale on which magnetic field decays (Myr).
Default = 1000.0

--pulsar-minimum-magnetic-field
\(log_{10}\) of the minimum pulsar magnetic field (Gauss).
Default = 8.0

--pulsational-pair-instability
Enable mass loss due to pulsational-pair-instability (PPI).
Default = TRUE

--pulsational-pair-instability-prescription
Pulsational pair instability prescription.
Options: { HENDRIKS, COMPAS, STARTRACK, MARCHANT, FARMER }
HENDRIKS implements the prescription from Hendriks et al. 2023
COMPAS, STARTRACK and MARCHANT follow Woosley 2017, Belczynski et al. 2016, and Marchant et al. 2018, all as implemented in Stevenson et al. 2019.
FARMER follows Farmer et al. 2019
Default = MARCHANT

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--quiet
Suppress printing to stdout.
Default = FALSE

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--radial-change-fraction
Approximate desired fractional change in stellar radius on phase when setting SSE and BSE timesteps (applied before --timestep--multiplier).
Recommended value is 0.005.
A value of 0.0 means that this choice is ignored and timestep estimates will be calculated by COMPAS.
Default = 0

--random-seed
Value to use as the seed for the random number generator.
Default = 0

--remnant-mass-prescription
Remnant mass prescription.
Options: { HURLEY2000, BELCZYNSKI2002, FRYER2012, FRYER2022, MULLER2016, MULLERMANDEL, SCHNEIDER2020, SCHNEIDER2020ALT, MALTSEV2024 }
Default = MULLERMANDEL

--retain-core-mass-during-caseA-mass-transfer
If TRUE, preserve a larger donor core mass following case A mass transfer.
The core is set equal to the expected core mass of a newly formed HG star with mass equal to that of the donor, scaled by the fraction of the donor's MS lifetime at mass transfer.
Default = TRUE

--revised-energy-formalism-nandez-ivanova
Enable revised energy formalism of Nandez & Ivanova.
Default = FALSE

--rlof-printing
Print RLOF events to logfile.
Default = TRUE

--rocket-kick-magnitude-1
Magnitude of post-SN pulsar rocket kick for the primary, in km/s.
Default = 0.0

--rocket-kick-magnitude-2
Magnitude of post-SN pulsar rocket kick for the secondary, in km/s.
Default = 0.0

--rocket-kick-phi-1
The in-plane angle \([0.0, 2pi)\) of the rocket kick velocity that primary neutron star receives following the supernova.
Default = 0.0

--rocket-kick-phi-2
The in-plane angle \([0.0, 2pi)\) of the rocket kick velocity that secondary neutron star receives following the supernova.
Default = 0.0

--rocket-kick-theta-1
The polar angle [0, pi] of the rocket kick velocity that primary neutron star receives following the supernova. 0 is aligned with orbital AM.
Default = 0.0

--rocket-kick-theta-2
The polar angle \([0, pi]`\) of the rocket kick velocity that secondary neutron star receives following the supernova. 0 is aligned with orbital AM.
Default = 0.0

--rotational-frequency
Initial rotational frequency of the star for SSE (Hz).
Default = 0.0 (--rotational-velocity-distribution used if --rotational-frequency not specified)

--rotational-frequency-1
Initial rotational frequency of the primary star for BSE (Hz).
Default = 0.0 (--rotational-velocity-distribution used if --rotational-frequency-1 not specified)

--rotational-frequency-2
Initial rotational frequency of the secondary star for BSE (Hz).
Default = 0.0 (--rotational-velocity-distribution used if --rotational-frequency-2 not specified)

--rotational-velocity-distribution
Initial rotational velocity distribution.
Options: { ZERO, HURLEY, VLTFLAMES }
ZERO sets all initial rotational velocities to 0.0.
HURLEY and VLTFLAMES sample initial rotational velocities from the Hurley, Pols, Tout (2000) and Ramirez-Agudelo et al. (2013,2015), respectively
Default = ZERO

--RSG-mass-loss
Red supergiant mass loss prescription.
Options: { NONE, ZERO, VINKSABHAHIT2023, BEASOR2020, DECIN2023, YANG2023, KEE2021, NJ90 }
NONE/ZERO turns off mass loss for giant stars (stellar types CHeB, FGB, EAGB, TPAGB) below the RSG_MAXIMUM_TEMP.
Default = DECIN2023
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --RSG-mass-loss-prescription in future.
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

--RSG-mass-loss-prescription
Red supergiant mass loss prescription.
Options: { NONE, ZERO, VINKSABHAHIT2023, BEASOR2020, DECIN2023, YANG2023, KEE2021, NJ90 }
NONE/ZERO turns off mass loss for giant stars (stellar types CHeB, FGB, EAGB, TPAGB) below the RSG_MAXIMUM_TEMP.
Default = DECIN2023
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

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--scale-CHE-mass-loss-with-surface-helium-abundance
Scale mass loss for chemically homogeneously evolving (CHE) stars with the surface helium abundance. Transition from OB to WR mass loss towards the end of the main sequence. Default = False

--scale-terminal-wind-velocity-with-metallicity-power
Scale terminal wind velocity with metallicity to this power Default = 0.0

--semi-major-axis
Initial semi-major axis for a binary star when evolving in BSE mode (AU).
Default = 0.1

--semi-major-axis-distribution [ -a ]
Initial semi-major axis distribution.
Options: { FLATINLOG, DUQUENNOYMAYOR1991, SANA2012 }
Default = FLATINLOG

--semi-major-axis-max
Maximum semi-major axis to generate (AU).
Default = 1000.0

--semi-major-axis-min
Minimum semi-major axis to generate (AU).
Default = 0.01

--stellar-zeta-prescription
Prescription for convective donor radial response zeta.
Options: { SOBERMAN, HURLEY, ARBITRARY }
The prescription only applies to stars with convective envelopes.
Stars with radiative envelopes take the values from --zeta-main-sequence or --zeta-radiative-giant-star.
SOBERMAN uses zeta from Soberman, Phinney, and van den Heuvel (1997).
HURLEY uses zeta from Hurley, Pols, Tout (2002).
ARBITRARY uses fixed value set in --zeta-adiabatic-arbitrary.
Default = SOBERMAN

--store-input-files
Enables copying of any specified grid file and/or logfile-definitios file to the COMPAS output container.
Default = TRUE

--switch-log
Enables printing of the Switch Log logfile.
Default = FALSE

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--tides-prescription
Prescription for tidal evolution of the binary.
Options: { NONE, PERFECT, KAPIL2024 }
NONE disables tidal interactions.
PERFECT evolves the binary assuming instantaneous synchronization and circularization.
KAPIL2024 uses the prescription from Kapil+ (2024). When using this prescription, set --chemically-homogeneous-evolution-mode NONE to avoid conflicts with stellar spins.
Default = NONE

--timestep-filename
User-defined timesteps filename. (See Timestep files)
Default = ’’ (None)

--timestep-multiplier
Multiplicative factor for timestep duration.
Default = 1.0

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--use-mass-loss
Enable mass loss through winds.
Default = TRUE Note that setting this option to FALSE can have unexpected consequences, e.g., TPAGB stars that are prevented from losing mass cannot become white dwarfs, so will become massless remnants. This is a useful option for testing, but this setting is not recommended for production. It is better to use specific wind prescription controls, such as:
--cool-wind-mass-loss-multiplier
--LBV-mass-loss-prescription
--luminous-blue-variable-multiplier
--mass-loss-prescription
--overall-wind-mass-loss-multiplier
--wolf-rayet-multiplier

--use-mass-transfer
Enable mass transfer.
Default = TRUE

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--version [ -v ]
Prints COMPAS version string.

--VMS-mass-loss
Very massive main sequence mass loss prescription.
Options: { NONE, ZERO, VINK2011, SABHAHIT2023, BESTENLEHNER2020 }
Applied above the VMS_MASS_THRESHOLD (\(100 M_\odot\)) by default.
NONE/ZERO turns off VMS mass loss.
Default = SABHAHIT2023
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --VMS-mass-loss-prescription in future.
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

--VMS-mass-loss-prescription
Very massive main sequence mass loss prescription.
Options: { NONE, ZERO, VINK2011, SABHAHIT2023, BESTENLEHNER2020 }
Applied above the VMS_MASS_THRESHOLD (\(100 M_\odot\)) by default.
NONE/ZERO turns off VMS mass loss.
Default = SABHAHIT2023
DEPRECATION NOTICE: the value of NONE for this option has been deprecated and will soon be removed. Please use ZERO in future.

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--wolf-rayet-multiplier
Multiplicative constant for Wolf Rayet winds. Note that wind mass loss will also be multiplied by the overall-wind-mass-loss-multiplier.
Default = 1.0

--WR-mass-loss
Wolf-Rayet mass loss prescription.
Options: { BELCZYNSKI2010, SANDERVINK2023, SHENAR2019 }
Default = SANDERVINK2023
DEPRECATION NOTICE: this option has been deprecated and will soon be removed. Please use --WR-mass-loss-prescription in future.

--WR-mass-loss-prescription
Wolf-Rayet mass loss prescription.
Options: { BELCZYNSKI2010, SANDERVINK2023, SHENAR2019 }
Default = SANDERVINK2023

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--YAML-template
Template filename for creation of YAML file (see also --create-YAML-file).
Default = "" (No template file)

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--zeta-adiabatic-arbitrary
Value of logarithmic derivative of radius with respect to mass, \(\zeta\) adiabatic.
Default = \(1.0 \times 10^4\)

--zeta-main-sequence
Value of logarithmic derivative of radius with respect to mass, \(\zeta\) on the main sequence.
Default = 2.0

--zeta-radiative-giant-star
Value of logarithmic derivative of radius with respect to mass, \(\zeta\) for radiative-envelope giant-like stars (including Hertzsprung Gap (HG) stars).
Default = 6.5

Category listing

Go to the top of this page for the full alphabetical list of options with explanations and default values

Initial conditions

--initial-mass-function, --initial-mass, --initial-mass-1, --initial-mass-2, --initial-mass-min, --initial-mass-max, --initial-mass-power

--mass-ratio-distribution, --mass-ratio, --mass-ratio-min, --mass-ratio-max, --minimum-secondary-mass

--eccentricity-distribution, --eccentricity, --eccentricity-min, --eccentricity-max

--metallicity-distribution, --metallicity, --metallicity-min, --metallicity-max

--orbital-period-distribution, --orbital-period, --orbital-period-min, --orbital-period-max, --semi-major-axis-distribution, --semi-major-axis, --semi-major-axis-min, --semi-major-axis-max, --allow-rlof-at-birth, --allow-touching-at-birth

--rotational-velocity-distribution, --rotational-frequency, --rotational-frequency-1, --rotational-frequency-2

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Stellar evolution and winds

--use-mass-loss, --check-photon-tiring-limit, --cool-wind-mass-loss-multiplier, --luminous-blue-variable-prescription, --LBV-mass-loss-prescription --luminous-blue-variable-multiplier, --mass-loss-prescription, --overall-wind-mass-loss-multiplier, --wolf-rayet-multiplier, --expel-convective-envelope-above-luminosity-threshold, --luminosity-to-mass-threshold, --OB-mass-loss, --OB-mass-loss-prescription, --RSG-mass-loss, --RSG-mass-loss-prescription, --VMS-mass-loss, --vms-mass-loss-prescription, --WR-mass-loss, --WR-mass-loss-prescription

--chemically-homogeneous-evolution, --chemically-homogeneous-evolution-mode

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Mass transfer physics

--case-bb-stability-prescription, --convective-envelope-temperature-threshold, --critical-mass-ratio-prescription, --critical-mass-ratio-HG-degenerate-accretor, --critical-mass-ratio-HG-non-degenerate-accretor, --critical-mass-ratio-MS-high-mass-degenerate-accretor, --critical-mass-ratio-MS-high-mass-non-degenerate-accretor, --critical-mass-ratio-MS-low-mass-degenerate-accretor, --critical-mass-ratio-MS-low-mass-non-degenerate-accretor, --critical-mass-ratio-giant-degenerate-accretor, --critical-mass-ratio-giant-non-degenerate-accretor, --critical-mass-ratio-helium-HG-degenerate-accretor, --critical-mass-ratio-helium-HG-non-degenerate-accretor, --critical-mass-ratio-helium-MS-degenerate-accretor, --critical-mass-ratio-helium-MS-non-degenerate-accretor, --critical-mass-ratio-helium-giant-degenerate-accretor, --critical-mass-ratio-helium-giant-non-degenerate-accretor, --critical-mass-ratio-white-dwarf-degenerate-accretor, --critical-mass-ratio-white-dwarf-non-degenerate-accretor, --eddington-accretion-factor, --mass-transfer, --use-mass-transfer, --mass-transfer-accretion-efficiency-prescription, --mass-transfer-angular-momentum-loss-prescription, --mass-transfer-fa, --mass-transfer-jloss, --mass-transfer-jloss-macleod-linear-fraction-degen, --mass-transfer-jloss-macleod-linear-fraction-non-degen, --mass-transfer-rejuvenation-prescription, --mass-transfer-thermal-limit-accretor, --mass-transfer-thermal-limit-accretor-multiplier, --mass-transfer-thermal-limit-C, --retain-core-mass-during-caseA-mass-transfer, --stellar-zeta-prescription, --zeta-adiabatic-arbitrary, --zeta-main-sequence, --zeta-radiative-giant-star

--circulariseBinaryDuringMassTransfer, --angular-momentum-conservation-during-circularisation, --tides-prescription

--envelope-state-prescription, --common-envelope-alpha, --common-envelope-alpha-thermal, --common-envelope-formalism, --common-envelope-lambda-prescription, --common-envelope-lambda, --common-envelope-slope-kruckow, --common-envelope-lambda-multiplier, --common-envelope-lambda-nanjing-enhanced, --common-envelope-lambda-nanjing-interpolate-in-mass, --common-envelope-lambda-nanjing-interpolate-in-metallicity, --common-envelope-lambda-nanjing-use_rejuvenated-mass, --common-envelope-allow-main-sequence-survive, --common-envelope-allow-radiative-envelope-survive, --common-envelope-allow-immediate-RLOF-post-CE-survive, --common-envelope-mass-accretion-prescription, --common-envelope-mass-accretion-constant, --common-envelope-mass-accretion-min, --common-envelope-mass-accretion-max, --common-envelope-recombination-energy-density, --maximum-mass-donor-nandez-ivanova, --revised-energy-formalism-nandez-ivanova

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Supernovae

--remnant-mass-prescription, --fryer-supernova-engine, --fryer-22-fmix, --fryer-22-mcrit, --maximum-neutron-star-mass, --mcbur1, --allow-non-stripped-ECSN, --neutrino-mass-loss-BH-formation, --neutrino-mass-loss-BH-formation-value, --neutron-star-equation-of-state, --pair-instability-supernovae, --PISN-lower-limit, --PISN-upper-limit, --PPI-CO-Core-Shift-Hendriks, --PPI-lower-limit, --PPI-upper-limit, --pulsational-pair-instability, --pulsational-pair-instability-prescription

--pulsar-birth-magnetic-field-distribution, --pulsar-birth-magnetic-field-distribution-min, --pulsar-birth-magnetic-field-distribution-max, --pulsar-birth-spin-period-distribution, --pulsar-birth-spin-period-distribution-min, --pulsar-birth-spin-period-distribution-max, --pulsar-magnetic-field-decay-massscale, --pulsar-magnetic-field-decay-timescale, --pulsar-minimum-magnetic-field

--kick-magnitude-distribution, --kick-magnitude-sigma-CCSN-BH, --kick-magnitude-sigma-CCSN-NS, --kick-magnitude-sigma-ECSN, --kick-magnitude-sigma-USSN, --black-hole-kicks, --black-hole-kicks-mode, --fix-dimensionless-kick-magnitude, --kick-magnitude, --kick-magnitude-1, --kick-magnitude-2, --kick-magnitude-min, --kick-magnitude-max, --kick-magnitude-random, --kick-magnitude-random-1, --kick-magnitude-random-2, --kick-scaling-factor, -muller-mandel-kick-multiplier-BH, --muller-mandel-kick-multiplier-NS, --muller-mandel-sigma-kick

--kick-direction, --kick-direction-distribution, --kick-direction-power, --kick-mean-anomaly-1, --kick-mean-anomaly-2, --kick-phi-1, --kick-phi-2, --kick-theta-1, --kick-theta-2

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Administrative

--mode, --number-of-systems, --emit-gravitational-radiation, --evolve-double-white-dwarfs, --evolve-main-sequence-mergers, --evolve-pulsars, --evolve-unbound-systems, --include-WD-binaries-as-DCO, --mass-change-fraction, --maximum-evolution-time, --maximum-number-timestep-iterations, --radial-change-fraction, --random-seed, --timestep-multiplier, --timestep-filename

--fp-error-mode

--grid, --grid-start-line, --grid-lines-to-process

--add-options-to-sysparms, --debug-classes, --debug-level, --debug-to-file, --detailed-output, --detailed-output, --enable-warnings, --errors-to-file, --help, --notes, --notes-hdrs, --population-data-printing, --print-bool-as-string, --quiet, --version

--log-classes, --logfile-definitions, --logfile-name-prefix, --logfile-type, --log-level, --logfile-common-envelopes, --logfile-common-envelopes-record-types, --logfile-detailed-output, --logfile-detailed-output-record-types, --logfile-double-compact-objects, --logfile-double-compact-objects-record-types, --logfile-pulsar-evolution, --logfile-pulsar-evolution-record-type, --logfile-rlof-parameters, --logfile-rlof-parameters-record-types, --logfile-supernovae, --logfile-supernovae-record-types, --logfile-switch-log, --logfile-system-parameters, --logfile-system-parameters-record-types, --output-container, --output-path, --rlof-printing, --store-input-files, --switch-log, --hdf5-buffer-size, --hdf5-chunk-size

--create-YAML-file, YAML-template

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