Spatially resolved CIII]λ1909 emission in Haro 11

Genoveva Micheva, Göran Östlin, Jens Melinder, Matthew Hayes, M. S. Oey, Akio K. Inoue, Ikuru Iwata, Angela Adamo, Lutz Wisotzki, Kimihiko Nakajima

Research output: Contribution to journalArticlepeer-review


The CIII]1909 (hereafter, CIII]) line is the strongest ultraviolet emission line after Lyα and is therefore of interest to high redshift studies of star-forming (SF) galaxies near the epoch of reionization. It is thought that CIII] emission is strongest in galaxies with subsolar metallicity and low mass, however, spectral observations of numerous such galaxies at high and low redshift produce inconclusive or even contradictory results. We present the first ever CIII] imaging, obtained with HST/STIS for the low-redshift SF galaxy Haro 11. Cluster parameters like stellar mass, dust fraction and dust attenuation, and ionization parameter, obtained through spectral energy distribution fitting, show no correlation with the CIII] equivalent width (EW), which may be due to a combination of the limitation of the models and the age-homogeneity of the cluster population. Comparing the ratio of CIII] emission line flux from individual clusters to that of Hα, [OIII], and [OII] we find that the clusters with the highest EW(CIII]) can be reconciled only with Cloudy models with an extremely high C/O ratio of ≥ 1.4(C/O)☉ for an ionizing population of single stars, binary stars, or a mixture of binary stars and active galactic nuclei. Given the point-like nature of strong CIII], the integrated total strength of EW(CIII]) becomes dependent on the morphology of the galaxy, which would explain the large scatter in EW(CIII]) strengths, observed in galaxies with otherwise similar SF properties, and of similarly low metallicity and stellar mass.

Original languageEnglish
JournalUnknown Journal
Publication statusPublished - 2020 Oct 9


  • Haro 11
  • Interstellar medium
  • Photoionization
  • Starburst galaxies
  • Ultraviolet astronomy

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Spatially resolved CIII]λ1909 emission in Haro 11'. Together they form a unique fingerprint.

Cite this