J/A+A/542/A98 Hydrocarbon solids. optEC(s) model. II. (Jones, 2012)
Variations on a theme - the evolution of hydrocarbon solids:
III. Size-dependent properties - the optEC(s)(a) model.
Jones A.P.
<Astron. Astrophys. 542, A98 (2012)>
=2012A&A...542A..98J 2012A&A...542A..98J
ADC_Keywords: Interstellar medium; Models
Keywords: dust, extinction - ISM: general - ISM: molecules
Abstract:
The properties of hydrogenated amorphous carbon (a-C:H) dust evolve in
response to the local radiation field in the inter- stellar medium and
the evolution of these properties is particularly dependent upon the
particle size.
A model for finite-sized, low-temperature amorphous hydrocarbon
particles, based on the microphysical properties of random and
defected networks of carbon and hydrogen atoms, with surfaces
passivated by hydrogen atoms, has been developed.
The eRCN/DG and the optEC(s) models have been combined, adapted and
extended into a new optEC(s) (a) model that is used to calculate the
optical properties of hydrocarbon grain materials down into the
sub-nanometre size regime, where the particles contain only a few tens
of carbon atoms.
Description:
optEC(s) model Kramers-Kronig-derived real part of the complex index
of refraction, n, from the analytically-derived values of k for a-C:H
as a function of wavelength [micron], energy E [eV] and band gap Eg
[eV] particle radius = 0.33nm, 0.1nm, 1nm, 3nm, 10nm, 30nm and 100nm.
optEC(s) model analytically-derived fits to the imaginary part of the
complex index of refraction, k, for a-C:H as a function of wavelength
[micron], energy E [eV] and band gap Eg [eV] particle radius = 0.33nm,
0.5nm, 1nm, 3nm, 10nm, 30nm and 100nm.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
k0_33nm.dat 159 1000 k for particle radius = 0.33nm
k0_5nm.dat 159 1000 k for particle radius = 0.5nm
k1nm.dat 159 1000 k for particle radius = 1nm
k3nm.dat 159 1000 k for particle radius = 3nm
k10nm.dat 159 1000 k for particle radius = 10nm
k30nm.dat 159 1000 k for particle radius = 30nm
k100nm.dat 159 1000 k for particle radius = 100nm
n0_33nm.dat 159 1000 n for particle radius = 0.33nm
n0_5nm.dat 159 1000 n for particle radius = 0.5nm
n1nm.dat 159 1000 n for particle radius = 1nm
n3nm.dat 159 1000 n for particle radius = 3nm
n10nm.dat 159 1000 n for particle radius = 10nm
n30nm.dat 159 1000 n for particle radius = 30nm
n100nm.dat 159 1000 n for particle radius = 100nm
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See also:
J/A+A/540/A2 : Hydrocarbon solids. optEC(s) model (Jones, 2012)
Byte-by-byte Description of file: n*.dat
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Bytes Format Units Label Explanations
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1- 9 E9.4 um lambda Wavelength
11- 19 E9.4 eV E Energy equivalent to wavelength
21- 29 E9.4 --- n0 Real part of m(n,k) Eg = -0.1 eV (Eg-)
31- 39 E9.4 --- n1 Real part of m(n,k) Eg = 0.0 eV
41- 49 E9.4 --- n2 Real part of m(n,k) Eg = 0.1 eV
51- 59 E9.4 --- n3 Real part of m(n,k) Eg = 0.25 eV
61- 69 E9.4 --- n4 Real part of m(n,k) Eg = 0.5 eV
71- 79 E9.4 --- n5 Real part of m(n,k) Eg = 0.75 eV
81- 89 E9.4 --- n6 Real part of m(n,k) Eg = 1.0 eV
91- 99 E9.4 --- n7 Real part of m(n,k) Eg = 1.5 eV
101-109 E9.4 --- n8 Real part of m(n,k) Eg = 1.15 eV
111-119 E9.4 --- n9 Real part of m(n,k) Eg = 1.75 eV
121-129 E9.4 --- n10 Real part of m(n,k) Eg = 2.0 eV
131-139 E9.4 --- n11 Real part of m(n,k) Eg = 2.25 eV
141-149 E9.4 --- n12 Real part of m(n,k) Eg = 2.5 eV
151-159 E9.4 --- n13 Real part of m(n,k) Eg = 2.67 eV (Eg+)
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Byte-by-byte Description of file: k*.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 E9.4 um lambda Wavelength
11- 19 E9.4 eV E Energy equivalent to wavelength
21- 29 E9.4 --- k0 Imaginary part of m(n,k) Eg = -0.1 eV (Eg-)
31- 39 E9.4 --- k1 Imaginary part of m(n,k) Eg = 0.0 eV
41- 49 E9.4 --- k2 Imaginary part of m(n,k) Eg = 0.1 eV
51- 59 E9.4 --- k3 Imaginary part of m(n,k) Eg = 0.25 eV
61- 69 E9.4 --- k4 Imaginary part of m(n,k) Eg = 0.5 eV
71- 79 E9.4 --- k5 Imaginary part of m(n,k) Eg = 0.75 eV
81- 89 E9.4 --- k6 Imaginary part of m(n,k) Eg = 1.0 eV
91- 99 E9.4 --- k7 Imaginary part of m(n,k) Eg = 1.5 eV
101-109 E9.4 --- k8 Imaginary part of m(n,k) Eg = 1.15 eV
111-119 E9.4 --- k9 Imaginary part of m(n,k) Eg = 1.75 eV
121-129 E9.4 --- k10 Imaginary part of m(n,k) Eg = 2.0 eV
131-139 E9.4 --- k11 Imaginary part of m(n,k) Eg = 2.25 eV
141-149 E9.4 --- k12 Imaginary part of m(n,k) Eg = 2.5 eV
151-159 E9.4 --- k13 Imaginary part of m(n,k) Eg = 2.67 eV (Eg+)
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History:
* 15-Jun-2012: First version
* 15-Aug-2012: Corrected version, from author
Acknowledgements:
Anthony Jones, Anthony.Jones(at)ias.u-psud.fr
References:
Jones, Paper I, 2012A&A...540A...1J 2012A&A...540A...1J
Jones, Paper II, 2012A&A...540A...2J 2012A&A...540A...2J, Cat. J/A+A/540/A2
(End) Anthony Jones [IAS], Patricia Vannier [CDS] 16-Apr-2012