Direct estimates of nitrogen abundance for Seyfert 2 nuclei
Fuente:
arXiv
Salvato in:
| Autori principali: | , , , , , , , , , , , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2024
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866911884768182272 |
|---|---|
| author | Dors, O. L. Cardaci, M. V. Hägele, G. F. Valerdi, M. Ilha, G. S. Oliveira, C. B. Riffel, R. A. Flury, S. R. Arellano-Córdova, K. Z. Storchi-Bergmann, T. Riffel, R. Almeida, G. C. Morais, I. N. |
| author_facet | Dors, O. L. Cardaci, M. V. Hägele, G. F. Valerdi, M. Ilha, G. S. Oliveira, C. B. Riffel, R. A. Flury, S. R. Arellano-Córdova, K. Z. Storchi-Bergmann, T. Riffel, R. Almeida, G. C. Morais, I. N. |
| contents | We derive the nitrogen and oxygen abundances in the Narrow Line Regions (NLRs) of a sample of 38 local ($z \: < \: 0.4$) Seyfert~2 nuclei. For that, we consider narrow optical emission line intensities and direct estimates of the electron temperatures ($T_{\rm e}$-method). We find nitrogen abundances in the range $7.6 \: < \: \rm 12+log(N/H) \: < \: 8.6$ (mean value $8.06\pm0.22$) or $\rm 0.4 \: < \: (N/N_{\odot}) \: < 4.7$, in the metallicity regime $8.3 \: < \: \rm 12+log(O/H) \: < \: 9.0$. Our results indicate that the dispersion in N/H abundance for a fixed O/H value in AGNs is in agreement with that for disc \ion{H}{ii} regions with similar metallicity. We show that Seyfert~2 nuclei follow a similar (N/O)-(O/H) relation to the one followed by star-forming objects. Finally, we find that active galaxies called as 'nitrogen-loud' observed at very high redshift ($z \: > \: 5$) show N/O values in consonance with those derived for local NLRs. This result indicates that the main star-formation event is completed in the early evolution stages of active galaxies. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2405_13906 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Direct estimates of nitrogen abundance for Seyfert 2 nuclei Dors, O. L. Cardaci, M. V. Hägele, G. F. Valerdi, M. Ilha, G. S. Oliveira, C. B. Riffel, R. A. Flury, S. R. Arellano-Córdova, K. Z. Storchi-Bergmann, T. Riffel, R. Almeida, G. C. Morais, I. N. Astrophysics of Galaxies We derive the nitrogen and oxygen abundances in the Narrow Line Regions (NLRs) of a sample of 38 local ($z \: < \: 0.4$) Seyfert~2 nuclei. For that, we consider narrow optical emission line intensities and direct estimates of the electron temperatures ($T_{\rm e}$-method). We find nitrogen abundances in the range $7.6 \: < \: \rm 12+log(N/H) \: < \: 8.6$ (mean value $8.06\pm0.22$) or $\rm 0.4 \: < \: (N/N_{\odot}) \: < 4.7$, in the metallicity regime $8.3 \: < \: \rm 12+log(O/H) \: < \: 9.0$. Our results indicate that the dispersion in N/H abundance for a fixed O/H value in AGNs is in agreement with that for disc \ion{H}{ii} regions with similar metallicity. We show that Seyfert~2 nuclei follow a similar (N/O)-(O/H) relation to the one followed by star-forming objects. Finally, we find that active galaxies called as 'nitrogen-loud' observed at very high redshift ($z \: > \: 5$) show N/O values in consonance with those derived for local NLRs. This result indicates that the main star-formation event is completed in the early evolution stages of active galaxies. |
| title | Direct estimates of nitrogen abundance for Seyfert 2 nuclei |
| topic | Astrophysics of Galaxies |
| url | https://arxiv.org/abs/2405.13906 |