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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
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:

       FileName      Lrecl  Records   Explanations

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


See also:
    J/A+A/540/A2 : Hydrocarbon solids. optEC(s) model (Jones, 2012)


Byte-by-byte Description of file: n*.dat

   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  ---     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+)


Byte-by-byte Description of file: k*.dat

   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+)


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
    Jones, Paper II, 2012A&A...540A...2J, Cat. J/A+A/540/A2
(End)          Anthony Jones [IAS], Patricia Vannier [CDS]    16-Apr-2012