Minor-merger-driven growth of early-type galaxies over the last 8 billion years

S. Kaviraj, R. M. Crockett, J. Silk, R. S. Ellis, S. K. Yi, R. W. O'Connell, Rogier Windhorst, B. C. Whitmore

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

We summarise recent progress in understanding the star formation activity in early-type galaxies (ETGs), using recent studies that leverage photometry in the rest-frame ultraviolet (UV) wavelengths. While classically thought to be old, passively-evolving systems, recent UV studies have revealed widespread star formation in ETGs, with ∼20% of the stellar mass in today's ETGs forming at late epochs (z < 1). A strong correlation is found between the presence of morphological disturbances and blue UV colours, suggesting that the star formation is merger-driven. However, the major merger rate at late epochs is far too low to satisfy the number of disturbed ETGs, indicating that minor mergers drive the star formation in these galaxies over the latter half of cosmic time. Together with the recent literature which suggests that minor mergers may drive the size evolution of massive ETGs, these results highlight the significant role of minor mergers in driving the evolution of massive galaxies in the low and intermediate-redshift Universe.

Original languageEnglish (US)
Title of host publicationProceedings of the International Astronomical Union
Pages460-464
Number of pages5
Volume7
EditionS284
DOIs
StatePublished - Sep 2011

Publication series

NameProceedings of the International Astronomical Union
NumberS284
Volume7
ISSN (Print)17439213
ISSN (Electronic)17439221

Fingerprint

galaxies
star formation
time measurement
stellar mass
photometry
disturbances
universe
color
wavelengths

Keywords

  • cD
  • galaxies: elliptical and lenticular
  • galaxies: evolution
  • galaxies: formation
  • galaxies: high-redshift
  • galaxies: interactions
  • ultraviolet: galaxies

ASJC Scopus subject areas

  • Astronomy and Astrophysics

Cite this

Kaviraj, S., Crockett, R. M., Silk, J., Ellis, R. S., Yi, S. K., O'Connell, R. W., ... Whitmore, B. C. (2011). Minor-merger-driven growth of early-type galaxies over the last 8 billion years. In Proceedings of the International Astronomical Union (S284 ed., Vol. 7, pp. 460-464). (Proceedings of the International Astronomical Union; Vol. 7, No. S284). https://doi.org/10.1017/S1743921312009623

Minor-merger-driven growth of early-type galaxies over the last 8 billion years. / Kaviraj, S.; Crockett, R. M.; Silk, J.; Ellis, R. S.; Yi, S. K.; O'Connell, R. W.; Windhorst, Rogier; Whitmore, B. C.

Proceedings of the International Astronomical Union. Vol. 7 S284. ed. 2011. p. 460-464 (Proceedings of the International Astronomical Union; Vol. 7, No. S284).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Kaviraj, S, Crockett, RM, Silk, J, Ellis, RS, Yi, SK, O'Connell, RW, Windhorst, R & Whitmore, BC 2011, Minor-merger-driven growth of early-type galaxies over the last 8 billion years. in Proceedings of the International Astronomical Union. S284 edn, vol. 7, Proceedings of the International Astronomical Union, no. S284, vol. 7, pp. 460-464. https://doi.org/10.1017/S1743921312009623
Kaviraj S, Crockett RM, Silk J, Ellis RS, Yi SK, O'Connell RW et al. Minor-merger-driven growth of early-type galaxies over the last 8 billion years. In Proceedings of the International Astronomical Union. S284 ed. Vol. 7. 2011. p. 460-464. (Proceedings of the International Astronomical Union; S284). https://doi.org/10.1017/S1743921312009623
Kaviraj, S. ; Crockett, R. M. ; Silk, J. ; Ellis, R. S. ; Yi, S. K. ; O'Connell, R. W. ; Windhorst, Rogier ; Whitmore, B. C. / Minor-merger-driven growth of early-type galaxies over the last 8 billion years. Proceedings of the International Astronomical Union. Vol. 7 S284. ed. 2011. pp. 460-464 (Proceedings of the International Astronomical Union; S284).
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