defs.h

Documentation for the global host and device definitions used across GPUmonty .

Global Variables

Variables

struct of_geom *geom: Global host data that holds the metric components for the simulation grid \( g_{μν}, g^{μν},\ \rm{and}\ \sqrt{- g} \) .

gsl_integration_workspace *w: Global host reusable workspace for tracking sub-intervals and error estimates during adaptive numerical integration used by GSL.

double F[N_ESAMP + 1]: Global host data array of precomputed emissivity values binned by frequency.

double wgt[N_ESAMP + 1]: Global host data array containing precomputed superphotons weights binned by frequency.

unsigned long long N_scatt: Global host data counter to keep track of the number of scattered superphotons per scattering layer.

unsigned long long N_superph_recorded: Global host data that holds the number of superphotons recorded into the spectrum.

double Rin: Global host variable representing the physical inner boundary of the simulation grid, e.g, the starting point of the physical domain.

double Rout: Global host variable representing the physical outer boundary of the simulation grid. It defines the edge of the grid for the simulation.

double Rh: Global host variable representing the event horizon of the black hole in Kerr-Schild coordinates

double R0: Global host variable representing a shift in the logarithmic radial coordinate.

double hslope: Global host variable for the latitude slope for Modified Kerr-Schild (MKS) coordinates

double startx[NDIM]: Global host array defining the start coordinate of the simulation grid in each dimension in native coordinates.

double stopx[NDIM]: Global host array defining the stop coordinate of the simulation grid in each dimension in native coordinates.

double dx[NDIM]: Global host array defining the grid spacing in each dimension in native coordinates.

double gam: Global host variable for the gas adiabatic index \( \Gamma \).

double Thetae_unit: Global host variable for the electron temperature unit to translate from cgs to code units.

double max_tau_scatt: Global host variable for the maximum optical depth found so far, used generally to calculate the biasing factor.

double dMact: Global host variable calculating the total amount of mass falling into the black hole per unit time.

double Ladv: Global host variable for the advection luminosity in CGS units.

double bias_norm: Global host variable for the bias normalization factor.

double *p: Global host pointer for accessing plasma properties.

int N1: Global host variable for the number of grid cells in the radial direction.

int N2: Global host variable for the number of grid cells in the poloidal direction.

int N3: Global host variable for the number of grid cells in the azimuthal direction.

double L_unit: Global host variable for the length unit conversion factor. Scales code units to centimeters (cm).

double B_unit: Global host variable for the magnetic field unit conversion factor. Scales code units to Gauss (G).

double Ne_unit: Global host variable for the electron number density unit conversion factor. Scales code units to \( \rm{cm}^-3\).

double Rho_unit: Global host variable for the mass density unit conversion factor. Scales code units to \(\rm{g/cm}^3\).

double U_unit: Global host variable for the internal energy density unit conversion factor. Scales code units to \(\rm{erg/cm}^3\).

double M_unit: Global host variable for the mass unit conversion factor. Scales code units to grams (g).

double T_unit: Global host variable for the time unit conversion factor. Scales code units to seconds (s).

double table[NW + 1][NT + 1]: Global host array for the precomputed hot cross section lookup table. It stores values indexed by photon energy ( \(\rm{N}_{\omega}\)) and electron temperature ( \(\rm{N}_\rm{T}\)).

double dlw: Global host variable for the logarithmic step size in photon frequency ( \(\Delta \ln \omega\)). It determines the resolution of the frequency axis in hotcross section precomputed lookup table.

double dlT: Global host variable for the logarithmic step size in electron temperature ( \(\Delta \ln \Theta_\rm{e}\)). It determines the resolution of the temperature axis in hotcross section precomputed lookup table.

double lminw: Global host variable for the minimum logarithmic photon frequency ( \(\ln \omega_{min}\)). Defines the lower boundary of the frequency grid for cross-section calculations.

double lmint: Global host variable for the minimum logarithmic electron temperature ( \(\ln \Theta_{e,min}\)). Defines the lower boundary of the temperature grid for cross-section calculations.

double nint[NINT + 1]: Global host array for the superphoton density distribution function.

double K2[N_ESAMP + 1]: Global host array for the precomputed values of the modified Bessel function of the second kind ( \(K_2\)).

double dndlnu_max[NINT + 1]: Global host array for the maximum values of the differential photon number distribution ( \(\frac{dN}{d\ln \nu}\)). Used for normalization and sampling in the scattering process.

__device__ curandState my_curand_state[N_BLOCKS * N_THREADS]: Global device array of curandState structures for random number generation on the GPU. It’s sized to accommodate all threads across all blocks.

__device__ double d_table[NW + 1][NT + 1]: Global device array for the precomputed hot cross section lookup table. It stores values indexed by photon energy ( \(\rm{N}_{\omega}\)) and electron temperature ( \(\rm{N}_\rm{T}\)). It’s the same as the host array table but accessible on the GPU.

__device__ unsigned long long photon_count = 0: Global device variable counter to keep track of the total number of superphotons generated from the grid during the simulation.

__device__ unsigned long long d_N_superph_recorded: Global device variable to keep track of the number of superphotons recorded into the spectrum.

__device__ int d_Ns: Global device variable for the target input number of superphotons to be generated in the simulation. It’s the same as the host variable Ns but accessible on the GPU.

__device__ unsigned long long d_N_scatt: Global device variable counter to keep track of the total number of scatterings that have occurred during the simulation.

__device__ double d_thetae_unit: Global device variable for the electron temperature unit to translate from cgs to code units. It’s the same as the host variable Thetae_unit but accessible on the GPU.

__device__ double d_startx[NDIM]: Global device array defining the start coordinate of the simulation grid in each dimension in native coordinates. It’s the same as the host array startx but accessible on the GPU.

__device__ double d_dx[NDIM]: Global device array defining the grid spacing in each dimension in native coordinates. It’s the same as the host array dx but accessible on the GPU.

__device__ double d_wgt[N_ESAMP + 1]: Global device array containing precomputed superphotons weights binned by frequency. It’s the same as the host array wgt but accessible on the GPU.

__device__ double d_F[N_ESAMP + 1]: Global device array of precomputed emissivity values binned by frequency. It’s the same as the host array F but accessible on the GPU.

__device__ double d_K2[N_ESAMP + 1]: Global device array for the precomputed modified Bessel function values binned by frequency. It’s the same as the host array K2 but accessible on the GPU.

__device__ double d_bias_norm: Global device variable for the bias normalization factor. It’s the same as the host variable bias_norm but accessible on the GPU.

__device__ double d_stopx[NDIM]: Global device array defining the stop coordinate of the simulation grid in each dimension in native coordinates. It’s the same as the host array stopx but accessible on the GPU.

__device__ double d_Rh: Global device variable representing the event horizon of the black hole in Kerr-Schild coordinates. It’s the same as the host variable Rh but accessible on the GPU.

__device__ double d_max_tau_scatt: Global device variable for the maximum optical depth found so far, used generally to calculate the biasing factor. It’s the same as the host variable max_tau_scatt but accessible on the GPU.

__device__ unsigned long long scattering_counter = 0: Global device variable counter to keep track of the number of scattered superphotons in the current scattering layer.

Note

This is different than d_N_scatt which counts the total number of scattering events in the simulation.

__device__ unsigned long long d_num_scat_phs[MAX_LAYER_SCA]: Global device array to keep track of the number of scattered superphotons per scattering layer.

Note

This is scattering_counter because scattered photons are stored layer by layer.

__device__ unsigned long long tracking_counter = 0: Global device variable counter to keep track of the number of photons being tracked in the current scattering batch. Used to dynamically allocate threads for photon tracking.

__device__ double d_nint[NINT + 1]: Global device array for the superphoton density distribution function. It mirrors the host array nint but is accessible on the GPU.

__device__ double d_dndlnu_max[NINT + 1]: Global device array for the maximum values of the differential photon number distribution ( \(\frac{dN}{d\ln \nu}\)). It mirrors the host array dndlnu_max but is accessible on the GPU.

__device__ double d_hslope = 0: Global device variable for the latitude slope for Modified Kerr-Schild (MKS) coordinates It mirrors the host variable hslope but is accessible on the GPU.

__device__ double d_R0 = 0: Global device variable representing a shift in the logarithmic radial coordinate. It mirrors the host variable Rin but is accessible on the GPU.

__device__ unsigned long long tracking_counter_sampling = 0: Global device variable counter to keep track of the number of photons being sampled in the current tracking batch. Used to dynamically allocate threads for photon sampling.

__device__ int d_N1: Global device variable for the number of grid cells in the radial direction. It mirrors the host variable N1 but is accessible on the GPU.

__device__ int d_N2: Global device variable for the number of grid cells in the poloidal direction. It mirrors the host variable N2 but is accessible on the GPU.

__device__ int d_N3: Global device variable for the number of grid cells in the azimuthal direction. It mirrors the host variable N3 but is accessible on the GPU.

__device__ double d_trat_small: Global device variable for the ion-to-electron temperature ratio in the low-beta limit ( \(R_{low}\)). This defines the temperature ratio in highly magnetized regions (where \(\beta \ll \beta_{\rm crit}\)).

__device__ double d_trat_large: Global device variable for the ion-to-electron temperature ratio in the high-beta limit ( \(R_{high}\)). This defines the temperature ratio in weakly magnetized regions (where \(\beta \gg \beta_{\rm crit}\)).

__device__ double d_beta_crit: Global device variable for the critical plasma beta value ( \(\beta_{\rm crit}\)) that delineates the transition between low-beta and high-beta temperature ratios.

__device__ double d_thetae_max: Global device variable for the maximum allowed dimensionless electron temperature ( \(\Theta_{e, max}\)). This sets an upper limit on the electron temperature to prevent unphysical values during the simulation.

__device__ double d_tp_over_te: Global device variable for the ion-to-electron temperature ratio ( \(T_p/T_e\)).

__device__ int d_scattering: Global device variable that controls whether scattering is enabled (1) or disabled (0) in the simulation.

__device__ double d_MBH: Global device variable for the black hole mass in grams (g).

__device__ double d_L_unit: Global device variable for the length unit conversion factor. Scales code units to centimeters (cm).

__device__ double d_B_unit: Global device variable for the magnetic field unit conversion factor. Scales code units to Gauss (G).

__device__ double d_Ne_unit: Global device variable for the electron number density unit conversion factor. Scales code units to \( \rm{cm}^-3\).

double bhspin: Global host variable for the black hole spin parameter ( \(a_*\)).

__device__ double d_bhspin: Global device variable for the black hole spin parameter ( \(a_*\)). It’s the same as the host variable bhspin but accessible on the GPU.

Params params = {0}: Global host variable to hold simulation parameters parsed by the parameter file.

struct of_geom: #include <decs.h>

struct of_spectrum: #include <decs.h>

struct params_t: #include <decs.h>