Cooling Radii

Class providing models of the cooling radius (in Mpc) for gas in the hot halo surrounding a galaxy, defined as the radius within which gas can radiate its thermal energy within a specified cooling time. Gas inside the cooling radius is expected to have cooled and infallen onto the galaxy, driving star formation. The growth rate of the cooling radius determines the rate at which new gas becomes available to cool, and together with the freefall radius sets which cooling regime (rapid cooling vs.quasi-static) applies to a given halo.

Default implementation: coolingRadiusSimple

Methods

radius → double precision

Returns the cooling radius for gas in the hot atmosphere surrounding the galaxy in node in units of Mpc.

  • type(treeNode), intent(inout), target :: node

radiusGrowthRate → double precision

Returns the rate of increase of the cooling radius for gas in the hot atmosphere surrounding the galaxy in node in units of Mpc/Gyr.

  • type(treeNode), intent(inout) :: node

coolingRadiusBetaProfile

A cooling radius class for \(\beta\)-profile halos. Computes the cooling radius by assuming that the hot gas density profile is a \(\beta\)-profile (\(\rho(r) \propto [r^2+r_\mathrm{c}^2]^{-1}\)), and that the cooling rate scales as density squared, \(\dot{E}\propto \rho^2\), such that the cooling time scales as inverse density, \(t_\mathrm{cool} \propto \rho^{-1}\). Consequently, the cooling radius is given by

\[r_\mathrm{cool} = r_\mathrm{virial} \left( \left[ {t_\mathrm{avail} \over t_0} - 1 \right] \left[ {t_\mathrm{virial} \over t_0} - 1 \right]^{-1} \right)^{1/2},\]

where \(t_0\), and \(t_\mathrm{virial}\) are the cooling times at zero radius and the virial radius respectively.

Methods

  • initialize — (Re)initialize the parameters of the \(\beta\)-profile mass distribution.

Parameters

  • [beta] (default 2.0d0/3.0d0) — The value of \(\beta\) in \(\beta\)-profile hot halo cold mode mass distributions.

  • [beta] (default 2.0d0/3.0d0) — The value of \(\beta\) in \(\beta\)-profile hot halo mass distributions.

  • [beta] (default 2.0d0/3.0d0) — The value \(\beta\) in a \(\beta\)-model mass distribution.

  • [densityNormalization] (default 0.0d0) — The density normalization of a \(\beta\)-model mass distribution.

  • [mass] (default 0.0d0) — The mass of a \(\beta\)-model mass distribution.

  • [outerRadius] (default 0.0d0) — The outer radius of a \(\beta\)-model mass distribution.

  • [coreRadius] (default 0.0d0) — The core radius of a \(\beta\)-model mass distribution.

  • [dimensionless] (default .false.) — If true then the \(\beta\)-model mass distribution is considered to be in dimensionless units.

  • [truncateAtOuterRadius] (default .false.) — If true then the \(\beta\)-model mass distribution is truncated beyond the outer radius.

  • [componentType] (default var_str('unknown')) — The component type that this mass distribution represents.

  • [massType] (default var_str('unknown')) — The mass type that this mass distribution represents.

coolingRadiusIsothermal

A cooling radius class that computes the cooling radius by assuming an isothermal density profile, and a cooling rate proportional to density squared. This implies a cooling time:

\[t_\mathrm{cool} \equiv {E\over\dot{E}} \propto \rho(r)^{-1}.\]

The cooling radius is then derived using

\[\rho(r_\mathrm{cool}) \propto t_\mathrm{available}^{-1}\]

which implies

\[r_\mathrm{cool} = r_\mathrm{virial} \left( { t_\mathrm{available} \over t_\mathrm{cool,virial}} \right)^{1/2},\]

where \(t_\mathrm{cool,virial}\) is the cooling time at the virial radius.

Methods

  • calculationReset — Reset memoized calculations.

coolingRadiusSimple

A cooling radius class that computes the cooling radius by seeking the radius at which the time available for cooling (see coolingTimeAvailable) equals the cooling time (see coolingTime). The growth rate is determined consistently based on the slope of the density profile, the density dependence of the cooling function and the rate at which the time available for cooling is increasing. This method assumes that the cooling time is a monotonic function of radius.

(Default implementation)

Methods

  • calculationReset — Reset memoized calculations.

Parameters

  • [efficiencyWind] (default 2.2157d-3) — The coupling efficiency of the black hole accretion-driven wind, defined as the fraction of the accreted rest-mass energy that is deposited as kinetic or thermal energy into the surrounding gas via AGN-driven outflows.

  • [redshiftReionization] (default 9.97d0) — The redshift of reionization below which baryonic accretion onto halos is suppressed due to the ionizing background heating the intergalactic medium and preventing gas from accreting onto low-mass halos.

  • [opticalDepthReionization] — The optical depth to electron scattering below which baryonic accretion is suppressed.

  • [velocitySuppressionReionization] (default 35.0d0) — The velocity scale below which baryonic accretion is suppressed.

  • [accretionNegativeAllowed] (default .true.) — Specifies whether negative accretion (mass loss) is allowed in the simple halo accretion model.

  • [accretionNewGrowthOnly] (default .false.) — Specifies whether accretion from the IGM is allowed only when a halo is growing past its previous greatest mass.

  • [acceptedStateCount] (default 100) — The number of states to use in acceptance rate statistics.

  • [timeStepRelative] (default 0.1d0) — The maximum allowed relative change in time for a single step in the evolution of a node.

  • [timeStepAbsolute] (default 1.0d0) — The maximum allowed absolute change in time (in Gyr) for a single step in the evolution of a node.

  • [timeStepMinimum] (default 1.0d-6) — The smallest timestep to use in profiling ODE solver steps.

  • [timeStepMaximum] (default 1.0d+1) — The largest timestep to use in profiling ODE solver steps.

  • [timeStepPointsPerDecade] (default 3) — The number of bins per decade of timestep to use when profiling ODE solver steps.

  • [wavelength] (default 1.0d4) — The wavelength of the photon packet (in AA).

  • [wavelengthMinimum] (default 0.5d4) — The minimum wavelength of the photon packet (in AA).

  • [wavelengthMaximum] (default 2.0d4) — The maximum wavelength of the photon packet (in AA).

  • [luminosity] (default 1.0d0) — The luminosity of the photon packet (in \(L_\odot\)).

  • [massRatioMajorMerger] (default 0.25d0) — The mass ratio above which mergers are considered to be “major”.

  • [destinationGasMinorMerger] (default var_str('spheroid')) — The component to which satellite galaxy gas moves to as a result of a minor merger.

  • [destinationStarsMinorMerger] (default var_str('spheroid')) — The component to which satellite galaxy stars move to as a result of a minor merger.

  • [degreesOfFreedom] (default 3.0d0) — Number of degrees of freedom to assume when computing the energy density of cooling gas in the “simple” cooling time class.

  • [timeScale] (default 1.0d0) — The timescale (in Gyr) for cooling in the simple cooling rate model.

  • [reionizationRedshift] (default 9.97d0) — The redshift of reionization in the simple IGM state model.

  • [reionizationTemperature] (default 1.0d4) — The post-reionization temperature (in units of Kelvin) in the simple IGM state model.

  • [preReionizationTemperature] (default 10.0d0) — The pre-reionization temperature (in units of Kelvin) in the simple IGM state model.

  • [useFormationHalo] (default .false.) — Specifies whether or not the “formation halo” should be used when solving for the radii of galaxies.

  • [solveForInactiveProperties] (default .true.) — If true, galactic structure is solved for during evaluation of inactive property integrals. Otherwise, structure is not solved for during this phase—this should only be used if the inactive property integrands do not depend on galactic structure.

  • [rateFractionalMaximum] (default 10.0d0) — The maximum fractional mass loss rate per dynamical time in the simple model of mass loss due to tidal stripping.

  • [beta] (default 1.0d0) — The scaling factor which multiplies the tidal mass loss rate.

  • [OmegaMatter] (default 0.3153d0) — The density of matter in the Universe in units of the critical density.

  • [OmegaBaryon] (default 0.04930d0) — The density of baryons in the Universe in units of the critical density.

  • [OmegaDarkEnergy] (default 0.6847d0) — The density of dark energy in the Universe in units of the critical density.

  • [temperatureCMB] (default 2.72548d0) — The present day temperature of the CMB in units of Kelvin.

  • [HubbleConstant] (default 67.36d0) — The present day value of the Hubble parameter in units of km/s/Mpc.