Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Radiation processes in the Seyfert galaxy NGC 4151
Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, Avdelningen för matematik och naturvetenskap.
2012 (engelsk)Inngår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 547Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Aims. The main aim of this work was to investigate if the radiative process photoexcitation by accidental resonance (PAR) is producing Fe II lines in the UV region of NGC 4151. At the same time I searched for collisionally excited Fe II emission. While doing so, the broad line region (BLR), intermediate line region (ILR) and narrow line region (NLR) contributions to the Mg II resonance doublet were also investigated. Methods. The focus was on the 2000 to 3000 Å wavelength region, in which decay from both the collisionally and PAR excited Fe II levels would form emission lines. I examined three archived Space Telescope Imaging Spectrograph (STIS) spectra of NGC 4151. Theoretical spectra based on calculated ranges for possible fluxes of the collisionally excited lines and pumping rates through the Fe II channels were then fitted to the observed spectra Results. I show that the UV region is influenced by PAR and that the Fe II fluorescence lines are clearly needed to explain the spectrum between 2000 to 3000 Å. The best fit of the theoretical spectra to the STIS spectra was obtained by assuming a similar radiation power of Fe+ ions and Mg+ ions. Conclusions. The PAR is active in the BLR of NGC 4151 and the total power of the Fe II fluorescence is a significant fraction of the total emission in the 2000 to 3000 wavelength region. Therefore it is important to incorporate this in models of NGC 4151 and possibly also in models of other active galactic nuclei. There are also many collisionally excited Fe II lines that are blended by each other and are therefore not individually observable in the NGC 4151 spectra.

sted, utgiver, år, opplag, sider
Springer , 2012. Vol. 547
Emneord [en]
atomic processes, line formation, active galaxies, NGC4151
HSV kategori
Identifikatorer
URN: urn:nbn:se:bth-7033DOI: 10.1051/0004-6361/201220248Lokal ID: oai:bth.se:forskinfo53D10264F1A51731C1257AF5003D12D0OAI: oai:DiVA.org:bth-7033DiVA, id: diva2:834608
Tilgjengelig fra: 2013-01-17 Laget: 2013-01-16 Sist oppdatert: 2017-12-04bibliografisk kontrollert

Open Access i DiVA

fulltekst(240 kB)594 nedlastinger
Filinformasjon
Fil FULLTEXT01.pdfFilstørrelse 240 kBChecksum SHA-512
efe8b551317e84b04d032eba97b7d594601867f2f525b805ad4c68a58bc90ef8532c7d76675d5fde5b9a6aefb6dfb780e226dcd8e7d343977bb3c604137e5470
Type fulltextMimetype application/pdf

Andre lenker

Forlagets fulltekst

Personposter BETA

Eriksson, Mattias

Søk i DiVA

Av forfatter/redaktør
Eriksson, Mattias
Av organisasjonen
I samme tidsskrift
Astronomy and Astrophysics

Søk utenfor DiVA

GoogleGoogle Scholar
Totalt: 594 nedlastinger
Antall nedlastinger er summen av alle nedlastinger av alle fulltekster. Det kan for eksempel være tidligere versjoner som er ikke lenger tilgjengelige

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 314 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf