Understanding the Blue-Sequence E/S0 Population: Fading Remnants and Future Spirals

Details Understanding the Blue-Sequence E/S0 Population: Fading Remnants and Future Spirals Understanding the Blue-Sequence E/S0 Population: Fading Remnants and Future Spirals

May 2006

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006sptz.prop30406k&link_type=abstract

Spitzer Proposal ID #30406

Computer Science

Scientific paper

Recent work has identified an intriguing population of field S0 and disky E galaxies that reside on the "blue sequence" in color-stellar mass parameter space --- i.e., the locus of spiral galaxies. While some must be young merger remnants destined to fade onto the red sequence, many appear to be settled products of long-ago mergers that have since rebuilt disks, as indicated by an unusually high frequency of extended counterrotating stellar disks and polar rings. Many also show signs of recent central star formation fueled by gas inflow, which may reflect disky "pseudobulge" growth involving bars and/or satellite interactions. Such galaxies could represent a long-sought missing link in the hierarchical picture of galaxy formation: disk regrowth in post-merger systems, potentially transforming E/S0s back into spirals. To examine possible disk and bulge growth in this population, we propose a MIPS 24-micron + IRAC 4-band imaging survey of 18 blue-sequence E/S0s and 13 red-sequence E/S0s, with the red-sequence systems serving as a control sample and enabling a search for dust-reddened examples of the same evolutionary processes seen in the blue-sequence systems. First, we will use stellar population analysis and dynamical/structural characteristics to identify disk-building systems, fading merger remnants, and disky or classical bulges. Second, we will measure the quantity and spatial distribution of current and recent star formation in both disks and bulges, to test whether (a) the two components grow in a time-coordinated way, (b) the amount of star formation is sufficient to transform galaxy morphology, and (c) the disk-building systems will grow to obey the scaling relations between disk/bulge radius, mass, and velocity dispersion observed for spirals. Spitzer is essential for this program because starbursts and dust clearly compromise optical/near-IR analyses of stellar populations and star formation in blue-sequence E/S0s and possible red-sequence analogues.

Affiliated with

Also associated with

No associations

Rating

Understanding the Blue-Sequence E/S0 Population: Fading Remnants and Future Spirals does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Understanding the Blue-Sequence E/S0 Population: Fading Remnants and Future Spirals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Understanding the Blue-Sequence E/S0 Population: Fading Remnants and Future Spirals will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-934061