J/MNRAS/406/460 IR absorbance spectra of olivine (Pitman+, 2010)
Infrared laboratory absorbance spectra of olivine: using classical dispersion
analysis to extract peak parameters.
Pitman K.M., Dijkstra C., Hofmeister A.M., Speck A.K.
<Mon. Not. R. Astron. Soc., 406, 460-481 (2010)>
=2010MNRAS.406..460P 2010MNRAS.406..460P
ADC_Keywords: Interstellar medium ; Spectra, infrared
Keywords: dust, extinction - methods: laboratory - techniques: spectroscopic -
infrared: general
Abstract:
Laboratory measurements quantifying the effect of Fe substituting
for Mg in olivine are needed to distinguish compositional from
temperature, grain size and grain shape effects in observational data.
To address this need, we study room temperature absorption spectra of
a large suite of olivines evenly spaced across Mg and Fe compositions.
We apply the principle that classical dispersion theory may be used to
determine peak positions as well as peak widths, strengths and
possibly optical function (n(λ) and k(λ)) estimates from
absorption spectra of thin film samples of these olivines and two
additional isotropic and anisotropic minerals with varying hardness
and numbers of spectral bands. For olivine, we find that this method
provides good estimates of peak position and that accounting for
asymmetric peak shapes in this way increases the error on full width
at half-maximum and oscillator strengths. Values from classical
dispersion fits better match published n and k derived from
reflectivity of single crystals when the dust proxy is soft and the
thickness of the sample is independently constrained. Electronic data
and peak parameter trends for the laboratory olivine absorption
spectra and the viability of the extracted n and k are discussed
with regard to astronomy.
Description:
Experimental methods and characterization of the olivine samples
studied here were previously described by Hofmeister & Pitman (2007,
Phys. Chem. Mineral., 34, 319).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fo0nat.dat 24 2037 *Merged mid- and far-IR thin film absorbance spectra
of 0 per cent forsterite (natural sample)
fo0syn.dat 25 2091 *Merged mid- and far-IR thin film absorbance spectra
of 0 per cent forsterite (synthetic sample)
fo9nat.dat 26 2075 *Merged mid- and far-IR thin film absorbance spectra
of 9 per cent forsterite (natural sample)
fo14nat.dat 25 2212 *Merged mid- and far-IR thin film absorbance spectra
of 14 per cent forsterite (natural sample)
fo31nat.dat 24 2446 *Merged mid- and far-IR thin film absorbance spectra
of 31 per cent forsterite (natural sample)
fo41nat.dat 24 1985 *Merged mid- and far-IR thin film absorbance spectra
of 41 per cent forsterite (natural sample)
fo45nat.dat 24 1962 *Merged mid- and far-IR thin film absorbance spectra
of 45 per cent forsterite (natural sample)
fo50syn.dat 24 1669 *Merged mid- and far-IR thin film absorbance spectra
of 50 per cent forsterite (synthetic sample)
fo54nat.dat 24 2302 *Merged mid- and far-IR thin film absorbance spectra
of 54 per cent forsterite (natural sample)
fo63nat.dat 24 2386 *Merged mid- and far-IR thin film absorbance spectra
of 63 per cent forsterite (natural sample)
fo67syn.dat 24 1476 *Merged mid- and far-IR thin film absorbance spectra
of 67 per cent forsterite (synthetic sample)
fo68nat.dat 24 2711 *Merged mid- and far-IR thin film absorbance spectra
of 68 per cent forsterite (natural sample)
fo75syn.dat 25 1788 *Merged mid- and far-IR thin film absorbance spectra
of 75 per cent forsterite (synthetic sample)
fo80syn.dat 26 1649 *Merged mid- and far-IR thin film absorbance spectra
of 80 per cent forsterite (synthetic sample)
fo81met.dat 26 2306 *Merged mid- and far-IR thin film absorbance spectra
of 81 per cent forsterite (meteoritic sample)
fo91nat.dat 26 2483 *Merged mid- and far-IR thin film absorbance spectra
of 91 per cent forsterite (natural sample)
fo93nat.dat 25 2518 *Merged mid- and far-IR thin film absorbance spectra
of 93 per cent forsterite (natural sample)
fo100syn.dat 24 2751 *Merged mid- and far-IR thin film absorbance spectra
of 100 per cent forsterite (synthetic sample)
nbeta.dat 9 11 *Real indices of refraction (Bowen & Schairer 1935,
Am. J. Sci., 29, 197), by Fo composition
caonk.dat 32 4000 *Real and imaginary indices of refraction for CaO
saponnk.dat 32 4000 *Real and imaginary indices of refraction for saponite
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Note on fo0nat.dat: olivine Fo0Te5 (impurities: 3.20% MnO) [ref: FAYR713]
Source: Rockport, MA; Bowen, Schairer, & Posnjak (1933, Am. J. Sci., 26, 253)
diamond anvil cell thin film, temperature 18-19 degrees C (mid+far-IR)
Note on fo0syn.dat: Fo0 synthetic fayalite chunks [ref: FAYSY729]
Source: Finch, Clark, & Koop (1980, Am. Mineral., 65, 381); Hofmeister (1997,
Phys. Chem. Mineral., 24, 535)
Method: DAC thin film, T=18-19 degrees C (mid+far-IR)
Note on fo9nat.dat: Fo9Te2 (impurities: 1.58% MnO, 0.04% CaO) [ref: FO9KI713]
Source: Kiglapait Intrusion, Labrador; Morse (1996, J. Petrol., 37, 5, 1037)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 524cm-1)
Note on fo14nat.dat: Fo14Te2 (impurities: 1.33% MnO, 0.20% CaO) [ref: OLVKI720]
Source: Kiglapait Intrusion, Labrador; Morse (1996, J. Petrol., 37, 5, 1037)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 527cm-1)
Note on fo31nat.dat: Fo31Te1 (impurities: 0.77% MnO, 0.09% CaO) [ref: OLVKI719]
Source: Kiglapait Intrusion, Labrador; Morse (1996, J. Petrol., 37, 5, 1037)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 530cm-1)
Note on fo41nat.dat: Fo41 (impurities: 0.72% MnO, 0.06% CaO) [ref: OLSAF226]
Source: Rustenberg, Transvaal, S. Africa; Hofmeister & Pitman (2007, Phys.
Chem. Mineral., 34, 319)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 539cm-1)
Note on fo45nat.dat: Fo45 (impurities: 0.68% MnO, 0.81% CaO) [ref: OLVCM730]
Source: Camas Mor Muck, Scotland; Yoder & Sahama (1957, Am. Mineral., 42, 475)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 545cm-1)
Note on fo50syn.dat: Fo50 synthetic hortonolite [ref: HORTF230]
Source: B. Fegley/R. Burns; Burns & Huggins (1972, Am. Mineral., 57, 967)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 538cm-1)
Note on fo54nat.dat: olivine Fo54 (impurities: 0.53% MnO) [ref: OLVFN730]
Source: Susimaki, Finland; Yoder & Sahama (1957, Am. Mineral., 42, 475)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 618cm-1)
Note on fo63nat.dat: Fo63 (impurities: 0.22% MnO, 0.02% CaO) [ref: OLVSK716]
Source: Skaergaard, E. Greenland; Yoder & Sahama (1957, Am. Mineral., 42, 475)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 560cm-1)
Note on fo67syn.dat: Fo67 synthetic olivine powder [ref: FO67722]
Source: R.M. Hazen (1977, Am. Mineral., 62, 286)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 787-830cm-1)
Note on fo68nat.dat: Fo68 (impurities: 0.11% MnO, 0.26% CaO) [ref: OLBUG716]
Source: Bufumbira, Uganda; Yoder & Sahama (1957, Am. Mineral., 42, 475)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 570cm-1)
Note on fo75syn.dat: Fo75 synthetic olivine powder [ref: FO75722]
Source: R.M. Hazen (1977, Am. Mineral., 62, 286)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 629-703cm-1)
Note on fo80syn.dat: Fo80 synthetic olivine powder [ref: FO80722]
Source: R.M. Hazen (1977, Am. Mineral., 62, 286)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 638cm-1)
Note on fo81met.dat: meteoritic Fo81 (impurities: 1.26% CaO) [ref: OLASM716]
Source: Alice Springs Meteorite; Yoder & Sahama (1957, Am. Mineral., 42, 475)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 632cm-1)
Note on fo91nat.dat: Fo91 (impurities: 0.12% MnO, 0.07% CaO, 0.39% NiO)
[ref: OLVSC722]
Source: Ward's Scientific -- San Carlos, AZ
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 632cm-1)
Note on fo93nat.dat: Fo93 (impurities: 0.074% MnO, 0.30% NiO) [ref: FORBG716]
Source: Balsam Gap, Jackson, NC; Hofmeister et al. (1989, Am. Mineral.,74, 281)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 600.4cm-1)
Note on fo100syn.dat: Fo100 synthetic forsterite [ref: KOFOR722]
Source: C. Koike; Koike, Shibai, & Tuchiyama (1993, MNRAS, 264, 654)
Method: DAC thin film, T=18-19 degC (mid+far-IR merged at 605cm-1)
Note on nbeta.dat: Value of n from Bowen & Schairer (1935, Am. J. Sci., 29, 197)
used to fit absorbance spectra via classical dispersion.
Note on caonk.dat, saponnk.dat: n and k values backed out from classical
dispersion fits.
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See also:
J/MNRAS/371/1744 : Identification of nitride dust (Pitman+, 2006)
Byte-by-byte Description of file: fo*
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Bytes Format Units Label Explanations
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1- 9 F9.4 cm-1 Freq [85/1420] Wavenumber (1)
16- 26 F11.8 [-] logAbs Absorbance (common log) (2)
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Note (1): Wavenumber (cm-1) = 10000 / wavelength (microns)
Note (2): Baseline-corrected absorbances are directly from the spectrometer
(i.e., in common logs). Multiply absorbance in tables by ln(10) to
compare to astronomical data.
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Byte-by-byte Description of file: nbeta.dat
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Bytes Format Units Label Explanations
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1- 3 I3 % Fo Forsterite composition (per cent Mg content)
5- 9 F5.3 --- n Real index of refraction
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Byte-by-byte Description of file: caonk.dat saponnk.dat
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Bytes Format Units Label Explanations
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1- 4 I4 cm-1 Freq [1,4000] Wavenumber
6- 16 F11.5 um Lambda Wavelength
18- 24 F7.5 --- n Real index of refraction
27- 32 F6.4 --- k Imaginary index of refraction
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History:
From electronic version of the journal
(End) Karly Pitman [JPL], Patricia Vannier [CDS] 23-Dec-2010