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Description
We present 'BYTe' a comprehensive 'hot' line list of ro-vibrational transitions of ammonia, ^14^NH_3_, in its ground electronic state. It comprises 1,138,323,351 transitions with frequencies up to 12,000cm^-1^, constructed from 1,373,897 energy levels below 18,000cm^-1^ having J values less than 37. The line list is sufficiently accurate and complete for high resolution spectroscopy and atmospheric modelling of astrophysical objects, including brown dwarfs and exoplanets at temperatures up to 1,500K. The data are in two parts. The first, nh3_0-41.dat contains a list of 4,167,360 rovibrational states, ordered by J (max= 41), symmetry block and energy (in cm^-1^). Only one third of the states (1,373,897) are within the parameters used for generating transitions (see above), but all the states are required for computing temperature-dependent partition functions. Each state is labelled with: seven normal mode vibrational quantum numbers; three rotational quantum numbers and the total symmetry quantum number, Gamma. In addition there are six local mode vibrational numbers and a local mode vibrational symmetry quantum numbers, which we include because the basis set used in our calculations is expressed in terms of these local mode quantum numbers. Each rovibrational state has a unique number, which is the number of the row in which it appears in the file. This number is the means by which the state is related to the second part of the data system, the transitions files. Because of their size, the transitions are listed in 120 separate files, each containing all the transitions in a 100cm^-1^ frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the lowest frequency in the range; thus the a-00500.dat file contains all the transitions in the frequency range 500-600cm^-1^. The transition files contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. The energy file and the transitions files are zipped, and need to be extracted before use. There is a Fortran 90 programme, sp_byte.f90 which may be used to generate synthetic spectra (see sp_byte.txt for details). Using this, it is possible to generate absorption or emission spectra in either 'stick' form or else convoluted with a gaussian with the half-width at half maximum being specified by the user, or with a the temperature-dependent doppler half-width. Three sample input files for use with sp_byte.f90 are supplied: "stick300.in", "gauss300.in", and "sp08900.in" (generates a spectrum for 8900-9000cm^-1^).
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