Intense C III] lambda lambda 1907,1909 emission from a strong Lyman continuum emitting galaxy
- We have obtained the first complete ultraviolet (UV) spectrum of a strong Lyman continuum (LyC) emitter at low redshift - the compact, low-metallicity, star-forming galaxy J1154+2443 - with a Lyman continuum escape fraction of 46% discovered recently. The Space Telescope Imaging Spectrograph spectrum shows strong Ly alpha and C III] lambda 1909 emission, as well as O III] lambda 1666. Our observations show that strong LyC emitters can have UV emission lines with a high equivalent width (e.g. EW(C III]) = 11.7 +/- 2.9 angstrom rest-frame), although their equivalent widths should be reduced due to the loss of ionizing photons. The intrinsic ionizing photon production efficiency of J1154+2443 is high, log(xi(0)(ion)) = 25.56 erg(-1) Hz, comparable to that of other recently discovered z similar to 0.3-0.4 LyC emitters. Combining our measurements and earlier determinations from the literature, we find a trend of increasing xi(0)(ion) with increasing C III] lambda 1909 equivalent width, which can be understood by a combination of decreasingWe have obtained the first complete ultraviolet (UV) spectrum of a strong Lyman continuum (LyC) emitter at low redshift - the compact, low-metallicity, star-forming galaxy J1154+2443 - with a Lyman continuum escape fraction of 46% discovered recently. The Space Telescope Imaging Spectrograph spectrum shows strong Ly alpha and C III] lambda 1909 emission, as well as O III] lambda 1666. Our observations show that strong LyC emitters can have UV emission lines with a high equivalent width (e.g. EW(C III]) = 11.7 +/- 2.9 angstrom rest-frame), although their equivalent widths should be reduced due to the loss of ionizing photons. The intrinsic ionizing photon production efficiency of J1154+2443 is high, log(xi(0)(ion)) = 25.56 erg(-1) Hz, comparable to that of other recently discovered z similar to 0.3-0.4 LyC emitters. Combining our measurements and earlier determinations from the literature, we find a trend of increasing xi(0)(ion) with increasing C III] lambda 1909 equivalent width, which can be understood by a combination of decreasing stellar population age and metallicity. Simple ionization and density-bounded photoionization models can explain the main observational features including the UV spectrum of J1154+2443.…
| Author details: | Daniel SchaererORCiD, Yuri I. IzotovORCiD, K. Nakajima, Gabor WorseckORCiD, J. Chisholm, A. Verhamme, T. X. Thuan, S. de Barros |
|---|---|
| DOI: | https://doi.org/10.1051/0004-6361/201833823 |
| ISSN: | 1432-0746 |
| Title of parent work (English): | Astronomy and astrophysics : an international weekly journal |
| Publisher: | EDP Sciences |
| Place of publishing: | Les Ulis |
| Publication type: | Article |
| Language: | English |
| Year of first publication: | 2018 |
| Publication year: | 2018 |
| Release date: | 2021/10/12 |
| Tag: | dark ages, reionization, first stars; galaxies: high-redshift; galaxies: starburst; ultraviolet: galaxies |
| Volume: | 616 |
| Number of pages: | 5 |
| Funding institution: | National Academy of Sciences of Ukraine [0116U003191]; Program of Fundamental Research of the Department of Physics and Astronomy [0117U000240]; JSPSMinistry of Education, Culture, Sports, Science and Technology, Japan (MEXT)Japan Society for the Promotion of Science; TRIPLE [ERC-stg-757258]; [HST-GO-15433.002-A] |
| Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
| DDC classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
| Peer review: | Referiert |
| Publishing method: | Open Access / Bronze Open-Access |
