Access to Astronomical Catalogues

← Click to display the menu
J/A+A/517/A60       Absorption coefficient of polystyrene    (Kannuchova+, 2010)

Space weathering of asteroidal surfaces. Influence on the UV-Vis spectra. Kannuchova Z., Baratta G.A., Garozzo M., Strazzulla G. <Astron. Astrophys. 517, A60 (2010)> =2010A&A...517A..60K
ADC_Keywords: Atomic physics ; Minor planets Keywords: minor planets, asteroids: general - methods: laboratory - techniques: spectroscopic Abstract: The surfaces of airless bodies in the Solar System are continuously altered by the bombardment of micrometeoroids and irradiation by solar wind, flares, and cosmic particles. Major effects of this process - space weathering - are darkening and "reddening" of the spectra of surface materials, as well as a "degrading" of absorption features. We studied the changes induced by energetic ion irradiation in the ultraviolet-visual-near-infrared (UV-Vis-NIR) (0.2-0.98um) reflectance spectra of targets selected to mimic the surfaces of airless bodies in the inner Solar System. Our chosen targets are olivine pellets, pure or covered by an organic polymer (polystyrene), which is transparent before irradiation. Polystyrene is used as a template for organic matter of low volatility that can be present on asteroidal surfaces. Moreover we measured the changes induced by ion irradiation in the absorption coefficient of the polymer. The purpose was to have a tool to better compare laboratory with observed spectra and distinguish between planetary objects with pure silicate surfaces and those whose surface is covered by organic matter exposed to cosmic ion bombardment. Description: The samples were irradiated in vacuum, at room temperature, with 200keV protons or 200-400keV argon ions. Before, during, and after irradiation diffuse reflectance spectra were acquired. Polystyrene films were also deposited on quartz substrates and irradiated while transmittance spectra were recorded. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file absar.dat 93 925 *Absorption coefficient of polystyrene in the wavelength range 250-980nm after irradiation with 400keV Ar++ absh.dat 80 960 *Absorption coefficient of polystyrene in the wavelength range 250-980nm after irradiation with 200keV H+
Note on absar.dat and absh.dat: dose is the total energy absorbed.
See also: http://web.ct.astro.it/weblab/dbindex.html : Experimental Astrophysics Laboratory Home Page Byte-by-byte Description of file: absar.dat
Bytes Format Units Label Explanations
1- 6 F6.2 nm lambda [250,980]?=- Wavelength 8- 21 E14.10 cm-1 Abs.coef1 ?=- Absorption coefficient for fluence=6.3x1012ions/cm2, dose=1.5eV/16u 23- 36 E14.10 cm-1 Abs.coef2 ?=- Absorption coefficient for fluence=3.8x1013ions/cm2, dose=9.1eV/16u 38- 51 E14.10 cm-1 Abs.coef3 ?=- Absorption coefficient for fluence=7.5x1013ions/cm2, dose=18.3eV/16u 53- 65 E13.10 cm-1 Abs.coef4 ?=- Absorption coefficient for fluence=1.5x1014ions/cm2, dose=36.5eV/16u 67- 79 E13.10 cm-1 Abs.coef5 ?=- Absorption coefficient for fluence=6.0x1014ions/cm2, dose=146eV/16u 81- 93 E13.10 cm-1 Abs.coef6 ?=- Absorption coefficient for fluence=5.2x1015ions/cm2, dose=1274.8eV/16u
Byte-by-byte Description of file: absh.dat
Bytes Format Units Label Explanations
1- 6 F6.2 nm lambda [250,980]Wavelength 8- 21 E14.10 cm-1 Abs.coef1 ?=- Absorption coefficient for fluence=2.5x1014ions/cm2, dose=6.6eV/16u 23- 36 E14.10 cm-1 Abs.coef2 ?=- Absorption coefficient for fluence=2.0x1015ions/cm2, dose=52.7eV/16u 38- 51 E14.10 cm-1 Abs.coef3 ?=- Absorption coefficient for fluence=4.0x1015ions/cm2, dose=105.5eV/16u 53- 66 E14.10 cm-1 Abs.coef4 ?=- Absorption coefficient for fluence=8.0x1015ions/cm2, dose=211.0eV/16u 68- 80 E13.10 cm-1 Abs.coef5 ?=- Absorption coefficient for fluence=1.6x1016ions/cm2, dose=422.0eV/16u
History: Copied at http://web.ct.astro.it/weblab/dbindex.html
(End) Patricia Vannier [CDS] 09-Aug-2010
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

catalogue service

© UDS/CNRS

Contact