2003A&A...407..159G


Query : 2003A&A...407..159G

2003A&A...407..159G - Astronomy and Astrophysics, volume 407, 159-176 (2003/8-3)

ISM properties in low-metallicity environments. II. The dust spectral energy distribution of NGC 1569.

GALLIANO F., MADDEN S.C., JONES A.P., WILSON C.D., BERNARD J.-P. and LE PEINTRE F.

Abstract (from CDS):

We present new 450 and 850µm SCUBA data of the dwarf galaxy NGC 1569. We construct the mid-infrared to millimeter SED of NGC 1569, using ISOCAM, ISOPHOT, IRAS, KAO, SCUBA and MAMBO data, and model the SED in order to explore the nature of the dust in low metallicity environments. The detailed modeling is performed in a self-consistent way, synthesizing the global ISRF of the galaxy using an evolutionary synthesis model with further constraints provided by the observed MIR ionic lines and a photoionisation model. Our results show that the dust properties are different in this low metallicity galaxy compared to other more metal rich galaxies. The results indicate a paucity of PAHs probably due to the destructive effects of the ISRF penetrating a clumpy environment and a size-segregation of grains where the emission is dominated by small grains of size ∼3nm, consistent with the idea of shocks having a dramatic effect on the dust properties in NGC 1569. A significant millimetre excess is present in the dust SED which can be explained by the presence of ubiquitous very cold dust (T=5-7K). This dust component accounts for 40 to 70% of the total dust mass in the galaxy (1.6-3.4x105M) and could be distributed in small clumps (size ≃ a few pc) throughout the galaxy. We find a gas-to-dust mass ratio of 740-1600, larger than that of the Galaxy and a dust-to-metals ratio of 1/4 to 1/7. We generate an extinction curve for NGC 1569, consistent with the modeled dust size distribution. This extinction curve has relatively steep FUV rise and smaller 2175Å bump, resembling the observed extinction curve of some regions in the Large Magellanic Cloud.

Abstract Copyright:

Journal keyword(s): ISM: dust, extinction - galaxies: dwarf - galaxies: starburst - infrared: galaxies - submillimeter

Simbad objects: 4

goto Full paper

goto View the references in ADS

Number of rows : 4
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
#notes
1 NAME SMC G 00 52 38.0 -72 48 01   2.79 2.2     ~ 10600 1
2 SBSG 0335-052 bCG 03 37 44.04 -05 02 38.5     16.65     ~ 456 1
3 NGC 1569 IG 04 30 49.186 +64 50 52.52 11.72 11.86 11.03     ~ 1212 3
4 NAME LMC G 05 23 34.6 -69 45 22     0.4     ~ 16636 1

To bookmark this query, right click on this link: simbad:objects in 2003A&A...407..159G and select 'bookmark this link' or equivalent in the popup menu


2023.03.27-03:06:27

© Université de Strasbourg/CNRS

    • Contact