2014A&A...570A..79P


C.D.S. - SIMBAD4 rel 1.7 - 2019.11.12CET15:38:40

2014A&A...570A..79P - Astronomy and Astrophysics, volume 570A, 79-79 (2014/10-1)

The difference in age of the two counter-rotating stellar disks of the spiral galaxy NGC 4138.

PIZZELLA A., MORELLI L., CORSINI E.M., DALLA BONTA E., COCCATO L. and SANJANA G.

Abstract (from CDS):

Galaxies accrete material from the environment through acquisitions and mergers. These processes contribute to the galaxy assembly and leave their fingerprints on the galactic morphology, internal kinematics of gas and stars, and stellar populations. The Sa spiral NGC 4138 is known to host two counter-rotating stellar disks, with the ionized gas co-rotating with one of them. We measured the kinematics and properties of the two counter-rotating stellar populations to constrain their formation scenario. A spectroscopic decomposition of the observed major-axis spectrum was performed to disentangle the relative contribution of the two counter-rotating stellar and one ionized-gas components. The line-strength indices of the two counter-rotating stellar components were measured and modeled with single stellar population models that account for the α/Fe overabundance. The counter-rotating stellar population is younger, marginally more metal poor, and more α-enhanced than the main stellar component. The younger stellar component is also associated with a star-forming ring. The different properties of the counter-rotating stellar components of NGC 4138 rule out the idea that they formed because of bar dissolution. Our findings support the results of numerical simulations in which the counter-rotating component assembled from gas accreted on retrograde orbits from the environment or from the retrograde merging with a gas-rich dwarf galaxy.

Abstract Copyright:

Journal keyword(s): galaxies: abundances - galaxies: spiral - galaxies: kinematics and dynamics - galaxies: formation - galaxies: stellar content - galaxies: individual: NGC 4138

Simbad objects: 7

goto Full paper

goto View the reference in ADS

Number of rows : 7

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 NGC 3593 GiG 11 14 36.9733686308 +12 49 05.505076217   11.8       ~ 323 2
2 NGC 4138 Sy1 12 09 29.788 +43 41 07.14 12.46 12.29 11.32 10.82   ~ 338 1
3 NGC 4550 GiP 12 35 30.612 +12 13 15.44 12.97 12.56 11.68     ~ 497 1
4 NGC 5179 LIN 13 29 30.890 +11 44 45.16   14.9       ~ 41 0
5 NGC 5713 GiP 14 40 11.528 -00 17 21.16 11.88 11.84 11.20     ~ 337 2
6 NGC 5719 GiP 14 40 56.393 -00 19 05.49   13.10   12.061   ~ 143 1
7 * 42 Peg PM* 22 41 27.7207176 +10 49 52.907917 3.10 3.33 3.41 3.43 3.50 B8V 281 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2014A&A...570A..79P and select 'bookmark this link' or equivalent in the popup menu


2019.11.12-15:38:40

© Université de Strasbourg/CNRS

    • Contact