scholarly journals The spectral energy distributions of the entire Herschel Reference Survey

2011 ◽  
Vol 7 (S284) ◽  
pp. 283-285
Author(s):  
Laure Ciesla ◽  

AbstractWe present the spectral energy distributions (SED) of the 323 galaxies of the Herschel Reference Survey. In order to provide templates for nearby galaxies calibrated on physical parameters, we computed mean SEDs per bin of morphological types and stellar masses. They will be very useful to study more distant galaxies and their evolution with redshift. This preliminary work aims to study how the most commonly used libraries (Chary & Elbaz 2001, Dale & Helou 2002 and Draine & Li 2007) reproduce the far-infrared emission of galaxies. First results show that they reproduce well the far-infrared part of mean SEDs. For single galaxies the Draine & Li (2007) models seem to reproduce very well the far-infrared emission, as does the Dale & Helou (2002).

2000 ◽  
Vol 175 ◽  
pp. 484-487 ◽  
Author(s):  
A.S. Miroshnichenko ◽  
K.S. Bjorkman

AbstractA sample of Be stars with large far-infrared excesses detected by IRAS is selected and their high-resolution IRAS images are examined. The far-infrared emission from most of them is marginally extended and is associated with the optical sources. Modeling of the stars’ spectral energy distributions allows us to rule out the infrared cirrus nature of the excesses. We suggest that the excesses are more likely due to circumstellar dust, possibly formed early in the evolution of the star.


2011 ◽  
Vol 7 (S284) ◽  
pp. 224-227
Author(s):  
M. Lacy ◽  
A. Sajina ◽  
A. O. Petric ◽  
S. E. Ridgway ◽  
D. M. Nielsen ◽  
...  

AbstractWe present preliminary results on fitting of SEDs to 142 z < 1 quasars selected in the mid-infrared. Our quasar selection finds objects ranging in extinction from highly obscured, type-2 quasars, through more lightly reddened type-1 quasars and normal type-1s. We find a weak tendency for the objects with the highest far-infrared emission to be obscured quasars, but no bulk systematic offset between the far-infrared properties of dusty and normal quasars as might be expected in the most naive evolutionary schemes. The hosts of the type-2 quasars have stellar masses comparable to those of radio galaxies at similar redshifts. Many of the type-1s, and possibly a one of the type-2s require a very hot dust component in addition to the normal torus emission.


2003 ◽  
Vol 590 (1) ◽  
pp. 128-148 ◽  
Author(s):  
Joanna K. Kuraszkiewicz ◽  
Belinda J. Wilkes ◽  
Eric ◽  
J. Hooper ◽  
Kim K. McLeod ◽  
...  

2019 ◽  
Vol 15 (S352) ◽  
pp. 246-247
Author(s):  
George H. Rieke ◽  
Maria Emilia De Rossi ◽  
Irene Shivaei ◽  
Volker Bromm ◽  
Jianwei Lyu

AbstractThe first massive galaxies (z ∼ 6) have (1) very high energy density due to their small diameters and extreme luminosities in young stars and (2) interstellar dust relatively deficient in carbon compared with silicates. Both of these attributes should raise their interstellar dust temperatures compared with lower redshift galaxies. Not only is this temperature trend observed, but the high-z spectral energy distributions (SEDs) are very broad due to very warm dust. As a result total infrared luminosities – and star formation rates – at the highest redshifts estimated by fitting blackbodies to submm- and mm-wave observations can be low by a factor of ∼2.


2010 ◽  
Vol 725 (1) ◽  
pp. 742-749 ◽  
Author(s):  
Adam Muzzin ◽  
Pieter van Dokkum ◽  
Mariska Kriek ◽  
Ivo Labbé ◽  
Iara Cury ◽  
...  

2000 ◽  
Vol 44 (4) ◽  
pp. 246-254 ◽  
Author(s):  
I. N. Glushneva ◽  
V. I. Shenavrin ◽  
I. A. Roshchina

Author(s):  
Yurika Yamada ◽  
Makoto Uemura ◽  
Ryosuke Itoh ◽  
Yasushi Fukazawa ◽  
Masanori Ohno ◽  
...  

Abstract We report on the variations of the physical parameters of the jet observed in the blazar Mrk 421, and discuss the origin of X-ray flares in the jet, based on analysis of several spectral energy distributions (SEDs). The SEDs are modeled using the one-zone synchrotron self-Compton model, its parameters determined using a Markov chain Monte Carlo method. The lack of data at TeV energies means many of the parameters cannot be uniquely determined and are correlated. These are studied in detail. We find that the optimal solution can be uniquely determined only when we apply a constraint to one of four parameters: the magnetic field (B), the Doppler factor, the size of the emitting region, and the normalization factor of the electron energy distribution. We used 31 sets of SEDs from 2009 to 2014 with optical–UV data observed with UVOT/Swift and the Kanata telescope, X-ray data with XRT/Swift, and γ-ray data with the Fermi Large Area Telescope. The result of our SED analysis suggests that, in the X-ray faint state, the emission occurs in a relatively small area (∼1016 cm) with a relatively strong magnetic field (B ∼ 10−1 G). The X-ray bright state shows a tendency opposite to that of the faint state, that is, a large emitting area (∼1018 cm), probably downstream of the jet, and a weak magnetic field (B ∼ 10−3 G). The high X-ray flux was due to an increase in the maximum energy of electrons. On the other hand, the presence of two kinds of emitting areas implies that the one-zone model is unsuitable for reproducing at least part of the observed SEDs.


2016 ◽  
Vol 818 (1) ◽  
pp. 62 ◽  
Author(s):  
Mohammadtaher Safarzadeh ◽  
Christopher C. Hayward ◽  
Henry C. Ferguson ◽  
Rachel S. Somerville

2011 ◽  
Vol 7 (S284) ◽  
pp. 279-282
Author(s):  
David L Clements ◽  

AbstractThe Herschel Space Observatory and the Planck satellite are providing radical improvements to our knowledge of the spectral energy distributions of galaxies in the far-IR and submm. We here present the results of the first combination of Herschel and Planck fluxes of local galaxies from the Herschel Reference Sample (HRS) survey, covering galaxies at distances between 15 and 25 Mpc. This combination provides information on SEDs in eight bands from 60μm, using IRAS, to 1.4mm using Planck. We apply a similar fitting procedure to this data as applied to the Planck ERCSC-detected nearby galaxies and confirm the result that dust significantly colder than 20K is common in local galaxies. It is early days for this kind of study, but it is clear that the new generation of satellites are already adding considerably to our knowledge of the far-IR/submm properties of galaxies.


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