Large binocular telescope observations of new six compact star-forming galaxies with [Ne v ] λ3426 Å emission
| العنوان: | Large binocular telescope observations of new six compact star-forming galaxies with [Ne |
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| المؤلفون: | Trinh X. Thuan, Yuri I. Izotov, Natalia G. Guseva |
| المصدر: | Monthly Notices of the Royal Astronomical Society. 508:2556-2574 |
| بيانات النشر: | Oxford University Press (OUP), 2021. |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | Physics, Active galactic nucleus, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Photoionization, Astrophysics, Compact star, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Spectral line, Galaxy, Stars, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Radiative transfer, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Line (formation) |
| الوصف: | We report the discovery of [NeV]3426 emission, in addition to HeII4686 emission, in six compact star-forming galaxies. These observations considerably increase the sample of eight such galaxies discovered earlier by our group. For four of the new galaxies, the optical observations are supplemented by near-infrared spectra. All galaxies, but one, have HII regions that are dense, with electron number densities of ~300-700 cm-3. They are all characterised by high Hbeta equivalent widths EW(Hbeta)~190-520A and high O32=[OIII]5007/[OII]3727 ratios of 10-30, indicating young starburst ages and the presence of high ionization radiation. All are low-metallicity objects with 12+logO/H=7.46-7.88. The spectra of all galaxies show a low-intensity broad component of the Halpha line and five out of six objects show Wolf-Rayet features. Comparison with photoionization models shows that pure stellar ionization radiation from massive stars is not hard enough to produce such strong [NeV] and HeII emission in our galaxies. The [NeV]3426/HeII4686 flux ratio of ~1.2 in J1222+3602 is consistent with some contribution of active galactic nucleus ionizing radiation. However, in the remaining five galaxies, this ratio is considerably lower 20 pages, 7 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society |
| تدمد: | 1365-2966 0035-8711 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::1946d52f65ddbcfb861cd404e0d8f450Test https://doi.org/10.1093/mnras/stab2798Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....1946d52f65ddbcfb861cd404e0d8f450 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 13652966 00358711 |
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