Abstract
I discuss observations of magnitude residuals from the B-band Tully-Fisher relationship, B - V color, chemical abundance gradients, and asymmetries in the H I and stellar disks of nearby spiral galaxies within the context of a model in which small satellites or H I clouds are accreted onto the outer disks of spiral galaxies. Correlations between the various observables support the hypothesis that accretion dilutes the gas-phase abundances in the outer disk, steepens the abundance gradient across the disk, increases the star formation rate, and creates asymmetries in the outer disk. By estimating the duration of steep abundance gradients, elevated rates of star formation, or outer disk asymmetries, we can place constraints on the rate of accretion events. The data suggest that accretion events at the current time are common.
| Original language | English (US) |
|---|---|
| Journal | Astrophysical Journal |
| Volume | 448 |
| Issue number | 1 PART 2 |
| State | Published - Jul 20 1995 |
| Externally published | Yes |
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Keywords
- Galaxies: abundances
- Galaxies: evolution
- Galaxies: interactions
ASJC Scopus subject areas
- Space and Planetary Science
Cite this
Evidence for recent accretion in nearby galaxies. / Zaritsky, Dennis F.
In: Astrophysical Journal, Vol. 448, No. 1 PART 2, 20.07.1995.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Evidence for recent accretion in nearby galaxies
AU - Zaritsky, Dennis F
PY - 1995/7/20
Y1 - 1995/7/20
N2 - I discuss observations of magnitude residuals from the B-band Tully-Fisher relationship, B - V color, chemical abundance gradients, and asymmetries in the H I and stellar disks of nearby spiral galaxies within the context of a model in which small satellites or H I clouds are accreted onto the outer disks of spiral galaxies. Correlations between the various observables support the hypothesis that accretion dilutes the gas-phase abundances in the outer disk, steepens the abundance gradient across the disk, increases the star formation rate, and creates asymmetries in the outer disk. By estimating the duration of steep abundance gradients, elevated rates of star formation, or outer disk asymmetries, we can place constraints on the rate of accretion events. The data suggest that accretion events at the current time are common.
AB - I discuss observations of magnitude residuals from the B-band Tully-Fisher relationship, B - V color, chemical abundance gradients, and asymmetries in the H I and stellar disks of nearby spiral galaxies within the context of a model in which small satellites or H I clouds are accreted onto the outer disks of spiral galaxies. Correlations between the various observables support the hypothesis that accretion dilutes the gas-phase abundances in the outer disk, steepens the abundance gradient across the disk, increases the star formation rate, and creates asymmetries in the outer disk. By estimating the duration of steep abundance gradients, elevated rates of star formation, or outer disk asymmetries, we can place constraints on the rate of accretion events. The data suggest that accretion events at the current time are common.
KW - Galaxies: abundances
KW - Galaxies: evolution
KW - Galaxies: interactions
UR - http://www.scopus.com/inward/record.url?scp=11944255000&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=11944255000&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:11944255000
VL - 448
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 1 PART 2
ER -