VI/142 Hydrogen emission and recombination coefficients - SS2 (Storey+, 2014)
Emission and recombination coefficients for hydrogen with kappa-distributed
electron energies.
Storey P.J., Sochi T.
<Mon. Not. R. Astron. Soc. 446, 1864 (2015)>
=2015MNRAS.446.1864S 2015MNRAS.446.1864S
=2014yCat.6142....0S 2014yCat.6142....0S
ADC_Keywords: Atomic physics
Keywords: hydrogen - atomic transitions - atomic spectroscopy -
emission coefficients - recombination coefficients -
total recombination coefficients - hydrogen two-photon emission -
hydrogen 2s state - planetary nebulae - nebular physics -
kappa electron energy distribution
Abstract:
This list provides an extensive data set for the emission and total
recombination coefficients of hydrogen and total recombination
coefficients to the 2s two-photon transitions with a kappa electron
energy distribution rather than the more traditional Maxwell-Boltzmann
distribution. The data are mainly relevant to thin and relatively cold
plasma found in planetary nebulae and HII regions. The data set is
complementary to previous data sets provided by Hummer and Storey [1]
and Storey and Hummer [2,3] under a Maxwell-Boltzmann distribution
assumption based on thermodynamic equilibrium. The data set is
structured as a function of electron number density, temperature and
kappa. An interactive fortran 77 and C++ data servers are also
provided as an accessory to probe the data and obtain
Lagrange-interpolated values in all three variables between the
explicitly given values.
Description:
The data set consists of two files: e1bk.d and t1bk.d. The first file
contains emission coefficients of hydrogen in units of erg.cm3/s
as a function of electron density (Ne), temperature (Te) and kappa.
The second file named 't1bk.d' contains the hydrogen total
recombination coefficients in Case B and the total recombination
coefficients to the 2s state of hydrogen in units of cm3/s as
a function of Ne, Te and kappa.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
e1bk.d 80 3852289 Emission coefficients of hydrogen
t1bk.d 80 1584 Hydrogen total recombination coefficients
intrat3D.cpp 152 644 C++ code
intrat3D.f 92 603 Fortran code
TestCase/* . 2 Examples
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See also:
VI/130 : High Accuracy Computed H2D+ Line List - ST1 (Sochi+, 2010)
VI/136 : Dielectronic Recombination Lines of C+ - SS1 (Sochi+, 2013)
VI/141 : Nebular [OIII] collision strengths - SSB (Storey+, 2014)
Description of file:
The structure of the first file, e1bk.d, is as follow:
(1) The first row contains (in the following order) the number of Ne
values (9) , the number of Te values (16) and the number of kappa
values (44) for which data are provided.
(2) The 9 values of Ne are specified by log10Ne = 2.0(0.5)6.0.
(3) The 16 values of Te are specified by
log10Te = 2.0(0.2)3.8, 3.9(0.1)4.4.
(4) The 44 values of kappa are specified by
log10kappa = 0.20(0.01)0.30, 0.35(0.05)1.0, 1.1(0.1)2.0,
2.2(0.2)3.0, 3.5, 4.0, 5.0, 6.0.
(5) The data therefore consist of 6336 blocks (=9x16x44).
(6) The first row of each block contains information about the block
which consists of the following:
Z log10Ne log10Te log10kappa B nmin nmax
where Z=1 is the atomic number of hydrogen, 'B' refers to Case B
and nmin and nmax are the minimum and maximum upper state
principal quantum numbers for which emission coefficients are
tabulated. Each block therefore contains 4850 [=(1/2)n(n-1)-1]
entries. These 4850 entries are arranged in 607 rows and hence the
total number of rows in each block is 608.
(7) Of the three variables, Ne Te and kappa, the fastest varying is
Ne followed by Te followed by kappa, and hence the ordinal number
of a block is given by:
OB=ON+(OT-1)9+(Oκ-1)144
where OB, ON, OT and Oκ are the ordinal numbers of
block, Ne value, Te value and kappa value respectively. For
example the ordinal number of the block for log10Ne=4 (ON=5),
log10Te=2.6 (OT=4) and log10kappa=0.27 (Oκ=8) is:
OB=5+(4-1)9+(8-1)144=1040
and hence it starts on row 631714 (=608(OB-1)+2) and ends on
row 632321 (=608 OB+1).
(8) The 4850 values of emission coefficients in each block are arranged
for transitions from upper levels nu to lower levels nl with
nu in descending order from nm, and nl in ascending order
from 1 to (nu-1), and hence the ordinal number for a transition
tr(nu,nl) is given by
Otr=nl+(1/2)(nm-nu)(nm+nu_-1)
Emission coefficients to n=1 are not calculated for Case B and hence
are set to zero.
As for the structure of the second file, t1bk.d, it contains 12672
entries arranged in 1584 rows. The first half (6336) of these entries
are the total recombination coefficients of hydrogen while the second
half are the total recombination coefficients to the 2s state. The
entries in each one of these two blocks correspond to the 6336 values
of physical conditions (i.e. various combinations of Ne, Te and
kappa) positioned according to the previously-explained order related
to the structure of the first file.
Full explanation of these data files and their structure is given in
the paper associated with this list (see above).
------------------------------------------------------------------------------
Interactive data servers:
These are fortran 77 and C++ codes which are provided as an accessory
to probe the data and obtain Lagrange-interpolated values in all three
variables (electron number density, temperature and kappa) between the
explicitly given values. These two codes provide identical
functionalities and hence they produce identical results. During the
execution of these programs, cues are given to guide the user and
obtain the required values. The user is advised to refer to the codes
where more explanatory comments are embedded within the codes. The
fortran 77 data server is compiled using gfortran, f77, and Intel
fortran compilers on Ubuntu 12.04 and Scientific Linux platforms,
while the C++ server is compiled using g++ compiler on Ubuntu 12.04
and Dev-C++ 5.7.1 and Microsoft Visual Studio 6.0 compilers on Windows
XP and Windows 8 64-bit versions. The numerical results of the servers
execution are written to a file titled "intrat3D.d". A test case
representing a sample input and output is provided in the associated
"TestCase" directory which includes the screenshot output and the
intrat3D.d file as obtained from running a simple test case.
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Acknowledgements:
P.J. Storey: University College London, pjs(at)star.ucl.ac.uk
Taha Sochi: University College London, t.sochi(at)ucl.ac.uk
References:
[1] Hummer D.G., Storey P.J. (1987MNRAS.224..801H 1987MNRAS.224..801H) Recombination-line
intensities for hydrogenic ions - I. Case B calculations for H I and He II.
[2] Storey P.J., Hummer D.G. (1988MNRAS.231.1139S 1988MNRAS.231.1139S) Recombination line
intensities for hydrogenic ions - II. Case B calculations for C VI, N VII
and O VIII.
[3] Storey P.J., Hummer D.G. (1995MNRAS.272...41S 1995MNRAS.272...41S, Cat. VI/64) Recombination
line intensities for hydrogenic ions - IV. Total recombination coefficients
and machine-readable tables for Z = 1 to 8.
(End) Taha Sochi [University College London], Patricia Vannier [CDS] 24-Oct-2014