Galaxy Zoo Talk

just a note from SIMBAD

  • Wisi_EU by Wisi_EU

    Red spirals are a very small fraction of all spirals at low masses, but are a significant fraction of the spiral population at large stellar masses showing that massive galaxies are red independent of morphology. We confirm that as expected, red spirals have older stellar populations and less recent star formation than the main spiral population. While the presence of spiral arms suggests that a major star formation could not have ceased a long ago (not more than a few Gyr), we show that these are also not recent post-starburst objects (having had no significant star formation in the last Gyr), so star formation must have ceased gradually. Intriguingly, red spirals are roughly four times as likely than the normal spiral population to host optically identified Seyfert/low-ionization nuclear emission region (LINER; at a given stellar mass and even accounting for low-luminosity lines hidden by star formation), with most of the difference coming from the objects with LINER-like emission. We also find a curiously large optical bar fraction in the red spirals, suggesting that the cessation of star formation and bar instabilities in spirals are strongly correlated.

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  • ChrisMolloy by ChrisMolloy in response to Wisi_EU's comment.

    Are red spirals found across all redshifts?

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  • Wisi_EU by Wisi_EU

    Hi Chris, yes... we find red (rather massive) galaxies at all distances. Those which are further are called DRGs (for Distant Red Galaxies ^^). Most of the time they present a typical ('descending rightwards') graphical pattern and they are also tagged in DR light spectra, but let's be careful not to generalize. there's an interesting article about patterns in SDSS here http://arxiv.org/pdf/1312.4477.pdf if you have time to read 😉
    LLAP

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  • ChrisMolloy by ChrisMolloy in response to Wisi_EU's comment.

    Thanks.

    Just downloaded the article and will read.

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