TY - JOUR
T1 - A GLOBAL STAR-FORMING EPISODE in M31 2-4 GYR AGO
AU - Williams, Benjamin F.
AU - Dalcanton, Julianne J.
AU - Dolphin, Andrew E.
AU - Weisz, Daniel R.
AU - Lewis, Alexia R.
AU - Lang, Dustin
AU - Bell, Eric F.
AU - Boyer, Martha
AU - Fouesneau, Morgan
AU - Gilbert, Karoline M.
AU - Monachesi, Antonela
AU - Skillman, Evan
N1 - Publisher Copyright:
© 2015. The American Astronomical Society. All rights reserved.
PY - 2015/6/10
Y1 - 2015/6/10
N2 - We have identified a major global enhancement of star formation in the inner M31 disk that occurred between 2-4 Gyr ago, producing ∼60% of the stellar mass formed in the past 5 Gyr. The presence of this episode in the inner disk was discovered by modeling the optical resolved star color-magnitude diagrams of low extinction regions in the main disk of M31 (3 < R < 20 kpc) as part of the Panchromatic Hubble Andromeda Treasury. This measurement confirms and extends recent measurements of a widespread star formation enhancement of similar age in the outer disk, suggesting that this burst was both massive and global. Following the galaxy-wide burst, the star formation rate of M31 has significantly declined. We briefly discuss possible causes for these features of the M31 evolutionary history, including interactions with M32, M33, and/or a merger.
AB - We have identified a major global enhancement of star formation in the inner M31 disk that occurred between 2-4 Gyr ago, producing ∼60% of the stellar mass formed in the past 5 Gyr. The presence of this episode in the inner disk was discovered by modeling the optical resolved star color-magnitude diagrams of low extinction regions in the main disk of M31 (3 < R < 20 kpc) as part of the Panchromatic Hubble Andromeda Treasury. This measurement confirms and extends recent measurements of a widespread star formation enhancement of similar age in the outer disk, suggesting that this burst was both massive and global. Following the galaxy-wide burst, the star formation rate of M31 has significantly declined. We briefly discuss possible causes for these features of the M31 evolutionary history, including interactions with M32, M33, and/or a merger.
KW - galaxies: evolution
KW - galaxies: individual (M31)
KW - galaxies: interactions
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U2 - 10.1088/0004-637X/806/1/48
DO - 10.1088/0004-637X/806/1/48
M3 - Article
AN - SCOPUS:84935014269
SN - 0004-637X
VL - 806
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
M1 - 48
ER -