163 lines
7 KiB
Text
163 lines
7 KiB
Text
######################
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# GENERAL PARAMETERS #
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######################
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# Plummer softening parameter (can be even 0)
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eps = 1E-4
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# End time of the calculation
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t_end = 0.25
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# Interval of snapshot files output
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dt_disk = 0.125
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# Interval for the energy control output (contr.dat)
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dt_contr = 0.125
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# Interval for SMBH output (bh.dat, bh_neighbors.dat, and bh_inf.dat)
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dt_bh = 0.125
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# Parameter for timestep determination
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eta = 0.01
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# Name of the input file; use "data.con" in most cases [default: data.con]
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#input_file_name = data.con
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# Number of devices (GRAPEs or GPUs per node) [default: 0]
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# By default, each MPI process will attempt to bind to one device. To change this behaviour, set the value to the number of available devices in the system. For example, if from some reason you want to run multiple MPI processes on a machine with a single device, set the value to 1 and use the mpirun utility (or whatever is used in your job scheduler) to launch as many processes as you like.
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#devices_per_node = 1
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##########
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# OUTPUT #
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##########
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# Whether to use HDF5 format for snapshot and restart; regular ASCII snapshorts are saved if false [default: false]
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#output_hdf5 = true
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# If using HDF5 output, use double precision or not [default: true]
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# Consider setting to false to save disk space. Restart file is always saved in double precision.
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#output_hdf5_double_precision = true
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# If using ASCII output, the number of digits after the decimal point [default: 10]
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# Restart file is saved with 16 digits after the decimal point.
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#output_ascii_precision = 6
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# Extra output: optionally save potential, acceleration and jerk in snapshot files [default: 0]
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# This is a number between 0 and 7 that encodes the output options in the following way:
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# [value] = [save jerk]*4 + [save acceleration]*2 + [save potential]
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# Example: choose 5 if it is needed to save the jerk and the potential, but not the acceleration for some reason.
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# Currently implemented in HDF5 output only.
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#output_extra_mode = 7
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# Whether to output a warning on the screen when the minimum time step is encountered. [default: false]
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#dt_min_warning = false
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####################
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# EXTERNAL GRAVITY #
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####################
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# Remember that external gravity models are applied at the same coordinate system as the particles. If the idea is to simulate a globular cluster orbiting in an external field, be sure to set the initial conditions appropriately (applying a shift to the coordinates and velocities).
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# Whether the parameters for the external gravitational field given below are in physical units or Hénon units. If true, the system used is {kiloparsec, solar mass, kilometre per second} [default: false]
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#ext_units_physical = true
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# If Physical units were selected, specify the simulation's unit mass (is solar masses) and unit lenght (in parsec; not kiloparsec)
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# TODO: add the option to normalize using other units.
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#unit_mass = 4E5 # MSun
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#unit_length = 15 # pc
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# The bulge is a Plummer potential with the following total mass and radius.
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#ext_m_bulge = 5E9 # MSun
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#ext_b_bulge = 1.9 # kpc
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# The disk is a Miyamoto-Nagai potential with the following total mass, scale length, and scale height
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#ext_m_disk = 6.8E10 # MSun
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#ext_a_disk = 3.00 # kpc
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#ext_b_disk = 0.28 # kpc
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# This halo option is yet another Plummer potential with the following total mass and radius.
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#ext_m_halo_plummer = 8E11 # MSun
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#ext_b_halo_plummer = 245 # kpc
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# This halo option is a logarithmic potential with the following velocity and radius parameters.
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#ext_log_halo_v = 240 # km/s
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#ext_log_halo_r = 1 # kpc
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# This is a spherical Dehnen model.
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#ext_dehnen_m = 1E11 # MSun
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#ext_dehnen_r = 2 # kpc
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#ext_dehnen_gamma = 0.5
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###################################
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# LIVE SUPERMASSIVE BLACK HOLE(S) #
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###################################
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# There is special treatment for particles representing supermassive black holes (SMBHs): they are integrated at every time step, they can have custom softening in SMBH-SMBH interactions, and post Newtonian terms can be added to the gravity.
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# The number of SMBH particles. Can be 0 (no SMBH), 1, or 2. [default: 0]
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#live_smbh_count = 2
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# Custom softening length for SMBH-SMBH interactions (can also be zero). If non-negative, the custom softening is applied. [default: -1]
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#live_smbh_custom_eps = 0
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# Output additional diagnostics about live SMBHs. [default: false]
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#live_smbh_output = true
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# Output additional diagnostics about the SMBH's (or SMBHs') nearest neighbours (number could be set as shown below). [default: false]
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#live_smbh_neighbor_output = true
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# Number of nearest neighbours to the SMBH (or SMBHs) to include in output. [default: 10]
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#live_smbh_neighbor_number = 10
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##################################
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# BINARY SUPERMASSIVE BLACK HOLE #
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##################################
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# The following parameters can be set when live_smbh_count is 2.
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# Output additional diagnostics about the sphere of influence (size could be set as shown below). [default: false]
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#binary_smbh_influence_sphere_output = true
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# The influence sphere is centred at the binary SMBH's centre of mass, and its radius is the semi-major axis of the binary times the factor below. [default: 10]
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#binary_smbh_influence_radius_factor = 20
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# Add post Newtonian terms to SMBH-SMBH gravity. [default: false]
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#binary_smbh_pn = true
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# A mask array (zeros and ones) determining whether or not to use specific post-Newtonian terms.
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# The elements represent {0, 1, 2, 2.5, 3, 3.5, spin} [default: {1,1,1,1,1,1,1}]
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#pn_usage = {1, 1, 1, 1, 0, 0, 0}
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# The speed of light in N-body units [default: 500]
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#pn_c = 477.12
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####################################
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# Negative powers of two #
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####################################
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# -1 1/2 0.5 #
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# -2 1/4 0.25 #
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# -3 1/8 0.125 #
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# -4 1/16 0.0625 #
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# -5 1/32 0.03125 #
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# -6 1/64 0.015625 #
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# -7 1/128 0.0078125 #
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# -8 1/256 0.00390625 #
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# -9 1/512 0.001953125 #
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# -10 1/1024 0.0009765625 #
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# -11 1/2048 0.00048828125 #
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# -12 1/4096 0.000244140625 #
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# -13 1/8192 0.0001220703125 #
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# -14 1/16384 0.00006103515625 #
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# -15 1/32768 0.000030517578125 #
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# -16 1/65536 0.0000152587890625 #
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####################################
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