J/A+A/606/A50ivo://CDS.VizieR/J/A+A/606/A50doi:10.26093/cds/vizier.36060050CDSDemyk K.Meny C.Leroux H.Depecker C.Brubach J.-B.Roy P.,Nayral C.Ojo W.-S.Delpech F.2017-10-10T14:48:56Z2017-10-09T09:23:28ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frinfrared-astronomyspectroscopyinterstellar-mediumTo model the cold dust emission observed in the diffuse interstellar medium, in dense molecular clouds or in cold clumps that could eventually form new stars, it is mandatory to know the physical and spectroscopic properties of this dust and to understand its emission. This work is a continuation of previous studies aiming at providing astronomers with spectroscopic data of realistic cosmic dust analogues for the interpretation of observations. The aim of the present work is to extend the range of studied analogues to iron-rich silicate dust analogues. Ferromagnesium amorphous silicate dust analogues were produced by a sol-gel method with a mean composition close to Mg_1-x_Fe_x_SiO_3_ with x=0.1, 0.2, 0.3, 0.4. Part of each sample was annealed at 500{deg}C for two hours in a reducing atmosphere to modify the oxidation state of iron. We have measured the mass absorption coefficient (MAC) of these eight ferromagnesium amorphous silicate dust analogues in the spectral domain 30-1000um for grain temperature in the range 10-300K and at room temperature in the 5-40um range. The MAC of ferromagnesium samples behaves in the same way as the MAC of pure Mg-rich amorphous silicate samples. In the 30-300K range, the MAC increases with increasing grain temperature whereas in the range 10-30K, we do not see any change of the MAC. The MAC cannot be described by a single power law in {lambda}^-{beta}^. The MAC of the samples does not show any clear trend with the iron content. However the annealing process has, on average, an effect on the MAC that we explain by the evolution of the structure of the samples induced by the processing. The MAC of all the samples is much higher than the MAC calculated by dust models. The complex behavior of the MAC of amorphous silicates with wavelength and temperature is observed whatever the exact silicate composition (Mg vs. Fe amount). It is a universal characteristic of amorphous materials, and therefore of amorphous cosmic silicates, that should be taken into account in astronomical modeling. The enhanced MAC of the measured samples compared to the MAC calculated for cosmic dust model implies that dust masses are overestimated by the models.2017A&A...606A..50Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/606/A50CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/606/A50https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/606/A50http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/606/A50https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/606/A50https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/606/A50http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/606/A50GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/A+A/606/A50/e10-10kMAC E10 10K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10-30kMAC E10 30K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10-200kMAC E10 200K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10-300kMAC E10 300K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10r10kMAC E10R 10K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10r100kMAC E10R 100K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10r30kMAC E10R 30K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10r200kMAC E10R 200K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10r300kMAC E10R 300K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20-30kMAC E20 30K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20r30kMAC E20R 30K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20r100kMAC E20R 100K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20r200kMAC E20R 200K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20r300kMAC E20R 300K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30-30kMAC E30 30K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30-100kMAC E30 100K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron dominant)MACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleJ/A+A/606/A50/e30-10kMAC E30 10K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30-200kMAC E30 200K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40-100kMAC E40 100K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40-200kMAC E40 200K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40-300kMAC E40 300K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40r30kMAC E40R 30K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e10-100kMAC E10 100K (amorphous composition Mg_0.9_Fe_0.1_SiO3, 10% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20-10kMAC E20 10K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20-100kMAC E20 100K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20-200kMAC E20 200K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20-300kMAC E20 300K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e20r10kMAC E20R 10K (amorphous composition Mg_0.8_Fe_0.2_SiO3, 20% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30-300kMAC E30 300K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30r30kMAC E30R 30K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30r10kMAC E30R 10K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30r100kMAC E30R 100K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30r200kMAC E30R 200K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron reduced)WavenumberWavenumbercm**-1em.wavenumberdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e30r300kMAC E30R 300K (amorphous composition Mg_0.7_Fe_0.3_SiO3, 30% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40-10kMAC E40 10K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40-30kMAC E40 30K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron dominant)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40r10kMAC E40R 10K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40r100kMAC E40R 100K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40r200kMAC E40R 200K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdoubleJ/A+A/606/A50/e40r300kMAC E40R 300K (amorphous composition Mg_0.6_Fe_0.4_SiO3, 40% iron, ferric iron reduced)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWavenumberWavenumbercm**-1em.wavenumberdoubleMACMass absorption coefficientcm**2.g**-1phys.absorption.coeffdouble