2008A&A...485....5Z


Query : 2008A&A...485....5Z

2008A&A...485....5Z - Astronomy and Astrophysics, volume 485, 5-20 (2008/7-1)

Where are the stars of the bar of NGC 1530 forming?

ZURITA A. and PEREZ I.

Abstract (from CDS):

NGC 1530 has one of the strongest bars ever observed and recent star formation sites are distributed across its bar. Our aim is to study the photometric properties of the bar and its HII regions, to elucidate the conditions under which HII regions form and their spatial relation to the principal dynamical features of the bar. We obtained BVRKs and Hα photometry of the HII regions of the bar in NGC 1530. Broad-band integrated colours and Hα equivalent widths were carefully measured and analysed as a function of position with respect to the main dust-lanes of the bar. We measured differences in the Hα equivalent widths of the HII regions that are located in the trailing and leading sides of the bar dust-lane. The possible factors that could produce this difference, such as [NII] contamination, Lyman-continuum-photon dust-extinction, escape of ionizing radiation, metallicity, IMF and age, were carefully analysed. Age differences were confirmed to be the most plausible explanation. This implies that HII regions that are located further away from the bar dust-lane in its leading side, downstream from the main bar dust-lane, are older than the rest by ∼1.5-2.5Myr. In addition, a clear spatial correlation has been found between: location of HII regions, dust spurs on the trailing side of the bar dust-lane, and the loci of maximum velocity gradients parallel to the bar major axis (possibly tracing gas flow towards the main bar dust-lane).These results support the hypothesis that massive stars are forming on the trailing side of the bar dust-lane, and age as they cross the bar, on a timescale that is compatible with the bar dynamics timescale.

Abstract Copyright:

Journal keyword(s): galaxies: structure - galaxies: individual: NGC 1530 - galaxies: ISM - galaxies: spiral - ISM: HII regions - galaxies: kinematics and dynamics

Simbad objects: 18

goto Full paper

goto View the references in ADS

Number of rows : 18
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2024
#notes
1 NGC 1530 AG? 04 23 27.102 +75 17 44.05   13.40       ~ 278 1
2 [RBZ2005] NGC 1530 16 HII ~ ~   21.0 20.5 19.8   ~ 1 0
3 [RBZ2005] NGC 1530 1 HII ~ ~   18.4 18.3 17.7   ~ 1 0
4 [RBZ2005] NGC 1530 94 HII ~ ~   23.2 23.3 22.8   ~ 1 0
5 [RBZ2005] NGC 1530 57 HII ~ ~   22.0 21.5 21.2   ~ 1 0
6 [RBZ2005] NGC 1530 86 HII ~ ~   23.6 23.6 22.6   ~ 1 0
7 [RBZ2005] NGC 1530 28 HII ~ ~   22.2 21.3 20.3   ~ 1 0
8 [RBZ2005] NGC 1530 9 HII ~ ~   20.2 19.9 19.1   ~ 1 0
9 [RBZ2005] NGC 1530 13 HII ~ ~   20.2 19.9 19.1   ~ 1 0
10 [RBZ2005] NGC 1530 51 HII ~ ~   22.1 21.4 20.9   ~ 1 0
11 [RBZ2005] NGC 1530 54 HII ~ ~   20.7 20.3 19.9   ~ 1 0
12 [RBZ2005] NGC 1530 21 HII ~ ~   21.1 20.4 19.8   ~ 1 0
13 [RBZ2005] NGC 1530 87 HII ~ ~   21.5 21.1 20.6   ~ 1 0
14 [RBZ2005] NGC 1530 36 HII ~ ~   19.8 19.7 19.4   ~ 1 0
15 [RBZ2005] NGC 1530 38 HII ~ ~       21.9   ~ 1 0
16 [RBZ2005] NGC 1530 92 HII ~ ~   23.0 22.5 22.8   ~ 3 0
17 [RBZ2005] NGC 1530 37 HII ~ ~   23 21.3 20.5   ~ 1 0
18 [RBZ2005] NGC 1530 12 HII ~ ~   20.2 19.5 18.9   ~ 1 0

To bookmark this query, right click on this link: simbad:objects in 2008A&A...485....5Z and select 'bookmark this link' or equivalent in the popup menu