J/ApJ/789/76 UV and IR properties for galaxies (Mao+, 2014)
Characterizing ultraviolet and infrared observational properties for galaxies.
II. Features of attenuation law.
Mao Y.-W., Kong X., Lin L.
<Astrophys. J., 789, 76 (2014)>
=2014ApJ...789...76M 2014ApJ...789...76M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Interstellar medium ; Photometry, infrared;
Photometry, ultraviolet
Keywords: dust, extinction - galaxies: ISM - galaxies: spiral -
infrared: galaxies - ultraviolet: galaxies
Abstract:
Variations in the attenuation law have a significant impact on
observed spectral energy distributions for galaxies. As one important
observational property for galaxies at ultraviolet and infrared
wavelength bands, the correlation between infrared-to-ultraviolet
luminosity ratio and ultraviolet color index (or ultraviolet spectral
slope), i.e., the IRX-UV relation (or IRX-β relation), offered a
widely used formula for correcting dust attenuation in galaxies, but
the usability appears to be in doubt now because of considerable
dispersion in this relation found by many studies. In this paper, on
the basis of spectral synthesis modeling and spatially resolved
measurements of four nearby spiral galaxies, we provide an
interpretation of the deviation in the IRX-UV relation with variations
in the attenuation law. From both theoretical and observational
viewpoints, two components in the attenuation curve, the linear
background and the 2175 Å bump, are suggested to be the parameters
in addition to the stellar population age (addressed in the first
paper of this series) in the IRX-UV function; different features in
the attenuation curve are diagnosed for the galaxies in our sample.
Nevertheless, it is often difficult to ascertain the attenuation law
for galaxies in actual observations. Possible reasons for preventing
the successful detection of the parameters in the attenuation curve
are also discussed in this paper, including the degeneracy of the
linear background and the 2175 Å bump in observational channels,
the requirement for young and dust-rich systems to study, and the
difficulty in accurate estimates of dust attenuations at different
wavelength bands.
Description:
Broadband FUV and NUV imaging data were obtained from GALEX
observations and downloaded from the Multimission Archive at Space
Telescope Science Institute (MAST) Web site (http://galex.stsci.edu/);
8um (dust-only) and 24um images were observed by the Spitzer Space
Telescope (Spitzer) and retrieved from the SINGS data distribution
service (http://irsa.ipac.caltech.edu/data/SPITZER/SINGS/). Hα
narrowband imaging data are also employed in this work. The Hα
narrowband image for NGC 3031 was observed by the 60/90 cm Schmidt
telescope at Xing-Long station of the National Astronomical
Observatories of China with the filter of transmission profile
FWHM∼120Å.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 119 400 Aperture Photometry of the UV Clusters
table4.dat 119 343 Aperture Photometry of the IR Clusters
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See also:
J/AJ/121/3048 : Multicolor photometry in NGC 1512 and NGC 5248 (Maoz+, 2001)
J/ApJS/143/377 : UV-to-FIR magnitudes for 83 starburst galaxies (Wu+, 2002)
J/ApJ/586/794 : Multiwavelength luminosities of galaxies (Bell, 2003)
J/ApJS/173/185 : GALEX ultraviolet atlas of nearby galaxies (Gil de Paz+, 2007)
J/ApJ/757/52 : UV and IR observations for SINGS galaxies. I. (Mao+, 2012)
J/ApJS/199/22 : UV to far-IR photometry of galaxies
(Hernandez-Fernandez+, 2012)
J/ApJ/783/135 : UV to IR fluxes of 221 early-type galaxies (Amblard+, 2014)
J/A+A/581/A33 : Nearby radio galaxies FUV to MIR properties (De Ruiter+, 2015)
J/AJ/150/31 : Photometry and redshifts of galaxies in the UDF
(Rafelski+, 2015)
Byte-by-byte Description of file: table3.dat table4.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- ID Identifier (1)
16- 22 F7.3 deg RAdeg Aperture Right Ascension (J2000)
24- 29 F6.3 deg DEdeg Aperture Declination (J2000)
31- 38 E8.2 10-7W LFUV GALEX/FUV band luminosity; erg/s (2)
40- 47 E8.2 10-7W e_LFUV Uncertainty in LFUV
49- 56 E8.2 10-7W LNUV GALEX/NUV band luminosity; erg/s (2)
58- 65 E8.2 10-7W e_LNUV Uncertainty in LNUV
67- 74 E8.2 10-7W LHa The Hα luminosity; erg/s (3)
76- 83 E8.2 10-7W e_LHa Uncertainty in LHa
85- 92 E8.2 10-7W L8 Spitzer/IRAC 8 micron band dust luminosity;
erg/s (3)
94-101 E8.2 10-7W e_L8 Uncertainty in L8
103-110 E8.2 10-7W L24 Spitzer/MIPS 24 micron band luminosity;
erg/s (3)
112-119 E8.2 10-7W e_L24 Uncertainty in L24
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Note (1): The aperture radius is 8.5'' for NGC 3031 and 6.8'' for NGC 4536,
NGC 5194, and NGC 7331.
Note (2): Luminosity measured after local background subtraction and corrected
for Galactic foreground extinction and aperture effects.
Note (3): Luminosity measured after local background subtraction and corrected
for aperture effects.
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History:
From electronic version of the journal
References:
Mao et al., Paper I, 2012ApJ...757...52M 2012ApJ...757...52M, Cat. J/ApJ/757/52
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 06-Mar-2017