sln-slab.1 (4422B)
1 .\" Copyright (C) 2022, 2026 |Méso|Star> (contact@meso-star.com) 2 .\" Copyright (C) 2026 Université de Lorraine 3 .\" Copyright (C) 2022 Centre National de la Recherche Scientifique 4 .\" Copyright (C) 2022 Université Paul Sabatier 5 .\" 6 .\" This program is free software: you can redistribute it and/or modify 7 .\" it under the terms of the GNU General Public License as published by 8 .\" the Free Software Foundation, either version 3 of the License, or 9 .\" (at your option) any later version. 10 .\" 11 .\" This program is distributed in the hope that it will be useful, 12 .\" but WITHOUT ANY WARRANTY; without even the implied warranty of 13 .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 .\" GNU General Public License for more details. 15 .\" 16 .\" You should have received a copy of the GNU General Public License 17 .\" along with this program. If not, see <http://www.gnu.org/licenses/>. 18 .Dd March 16, 2026 19 .Dt SLN-SLAB 1 20 .Os 21 .\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" 22 .Sh NAME 23 .Nm sln-slab 24 .Nd computations of radiative transfer in a 1D homogeneous slab 25 .\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" 26 .Sh SYNOPSIS 27 .Nm 28 .Op Fl hsv 29 .Op Fl n Ar nrealisations 30 .Op Fl T Ar thickness 31 .Op Fl t Ar threads 32 .Fl S Ar nu_min , Ns Ar nu_max 33 .Fl a Ar accel_struct 34 .Fl m Ar molparams 35 .Fl l Ar lines 36 .\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" 37 .Sh DESCRIPTION 38 .Nm 39 calculates the transmittance in a one-dimensional homogeneous slab of 40 arbitrary thickness using a Monte Carlo algorithm that samples the 41 spectral lines that make up the gas mixture. 42 This computation is accelerated by sampling the lines based on the 43 magnitude of their contribution to the mixture’s spectrum, so that few 44 Monte Carlo runs are required to estimate the transmissivity with a high 45 degree of confidence. 46 The core of the proposal rests on this sampling strategy, made possible 47 by constructing an acceleration structure from the set of lines in the 48 mixture. 49 A structure built using the 50 .Xr sln-build 1 51 utility and provided as input to the program. 52 .Pp 53 More than just a numerical simulation tool, 54 .Nm 55 is primarily designed to validate the aforementioned acceleration 56 structure in relation to its intended use, namely radiative transfer 57 calculations. 58 Thus, not only could an error be returned in the event of a problem with 59 the structure or its use, but the computed value can also contribute to 60 this validation through its comparison with the result of a calculation 61 of the same quantity performed by another radiative transfer code. 62 .Pp 63 The options are as follows: 64 .Bl -tag -width Ds 65 .\"""""""""""""""""""""""""""""""""" 66 .It Fl a Ar accel_struct 67 An acceleration structure corresponding to the input 68 .Ar lines , 69 used to accelerate their sampling based on their importance. 70 This structure is generated by the 71 .Xr sln-build 1 72 tool. 73 .\"""""""""""""""""""""""""""""""""" 74 .It Fl h 75 Display short help and exit. 76 .It Fl l Ar lines 77 List of lines from which the tree was built. 78 This list is in binary format as generated by the 79 .Xr shtr 1 80 binary, or in plain text HITRAN format, depending on whether the 81 .Fl s 82 option is set or not, respectively. 83 .\"""""""""""""""""""""""""""""""""" 84 .It Fl m Ar molparams 85 Isotopologue metadata in HITRAN format. 86 .\"""""""""""""""""""""""""""""""""" 87 .It Fl n Ar nrealisations 88 Number of Monte Carlo realisations. 89 By default the number of realisations is 10000. 90 .\"""""""""""""""""""""""""""""""""" 91 .It Fl S Ar nu_min , Ns Ar nu_max 92 The spectral range, in cm^-1, over which the computations are performed. 93 .\"""""""""""""""""""""""""""""""""" 94 .It Fl s 95 Specifies that input lines are formatted according to the binary format 96 as written by the 97 .Xr shtr 1 98 utility, and not according to the HITRAN format. 99 This format is more compact, allowing for faster loading of line data. 100 .\"""""""""""""""""""""""""""""""""" 101 .It Fl T Ar thickness 102 Slab thickness. 103 The default value is 1. 104 .\"""""""""""""""""""""""""""""""""" 105 .It Fl t Ar threads 106 Advice on the number of threads to use. 107 By default, 108 .Nm 109 uses many threads as processor cores. 110 .\"""""""""""""""""""""""""""""""""" 111 .It Fl v 112 Make 113 .Nm 114 verbose. 115 Multiple 116 .Fl v 117 options increase the verbosity. 118 The maximum is 3. 119 .El 120 .\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" 121 .Sh EXIT STATUS 122 .Ex -std 123 .\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" 124 .Sh SEE ALSO 125 .Xr sln-build 1