Skip to main content
SpringerLink
Log in

Diagnostics for the structure of AGNs’ broad line regions with reverberation mapping data: confirmation of the two-component broad line region model

  • Research Papers
  • Published:
Science China Physics, Mechanics and Astronomy Aims and scope Submit manuscript

Abstract

We re-examine the ten Reverberation Mapping (RM) sources with public data based on the two-component model of the Broad Line Region (BLR). In fitting their broad Hβ Mlines, six of them only need one Gaussian component, one of them has a double-peak profile, one has an irregular profile, and only two of them need two components, i.e., a Very Broad Gaussian Component (VBGC) and an Inter-Mediate Gaussian Component (IMGC). The Gaussian components are assumed to come from two distinct regions in the two-component model; they are the Very Broad Line Region (VBLR) and the Inter-Mediate Line region (IMLR). The two sources with a two-component profile are Mrk 509 and NGC 4051. The time lags of the two components of both sources satisfy t IMLR/t VBLR=V 2 VBLR/V 2 IMLR, where t IMLR and t VBLR are the lags of the two components while V IMLR and V VBLR represent the mean gas velocities of the two regions, supporting the two-component model of the BLR of Active Galactic Nuclei (AGNs). The fact that most of these ten sources only have the VBGC confirms the assumption that RM mainly measures the radius of the VBLR; consequently, the radius obtained from the R-L relationship mainly represents the radius of VBLR. Moreover, NGC 4051, with a lag of about 5 days in the one component model, is an outlier on the R-L relationship as shown in Kaspi et al. (2005); however this problem disappears in our two-component model with lags of about 2 and 6 days for the VBGC and IMGC, respectively.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. White R J, Peterson B M. Comments on cross-correlation methodology in variability studies of Active Galactic Nuclei. Publ Astron Soc Pac, 1994, 106: 879–889

    Article  ADS  Google Scholar 

  2. Hu C, Wang J M, Ho L C, et al. Hβ profiles in quasars: evidence for an intermediate-line region. Astrophys J, 2008, 683: L115–L118

    Article  ADS  Google Scholar 

  3. Sulentic J W, Marziani P, Zwitter T, et al. The Demise of the classical broad-line region in the luminous quasar PG 1416-129. Astrophys J, 2000, 545: L15–L18

    Article  ADS  Google Scholar 

  4. Zhu L, Zhang S-N, Tang S-M. Evidence for an intermediate line region in AGN’s inner torus and its evolution from narrow to broad line Seyfert I galaxies. Astrophys J, 2009, 700: 1173–1189

    Article  ADS  Google Scholar 

  5. Kaspi S, Maoz D, Netzer H, et al. The relationship between luminosity and broad line region size in Active Galactic Nuclei. Astrophys J, 2005, 629: 61–71

    Article  ADS  Google Scholar 

  6. Véron-Cetty M-P, Joly M, Véron P. The unusual emission line spectrum of IZw 1. Astron Astrophys, 2004, 417: 515–525

    Article  ADS  Google Scholar 

  7. Carone T E, Peterson B M, Bechtold J, et al. Optical continuum and emission-line variability of the Seyfert 1 galaxy Markarian 509. Astrophys J, 1996, 471: 737–747

    Article  ADS  Google Scholar 

  8. Peterson B M, Wanders I, Horne K, et al. On uncertainties in cross-correlation lags and the reality of wavelength-dependent continuum lags in Active Galactic Nuclei. PASP, 1998, 110: 660–670

    Article  ADS  Google Scholar 

  9. Peterson B M, McHardy I M, Wilkes B J, et al. X-ray and optical variability in NGC 4051 and the nature of narrow line seyfert 1 galaxies. Astrophys J, 2000, 542: 161–174

    Article  ADS  Google Scholar 

  10. Peterson B M, Ferrarese L, Gilbert K M, et al. Central masses and broad-line region sizes of Active Galactic Nuclei. II. A homogeneous analysis of a large reverberation mapping database. Astrophys J, 2004, 613: 682–699

    Article  ADS  Google Scholar 

  11. Denney K D, Watson L C, Peterson B M, et al. A revised broad line region radius and black hole mass for the narrow line seyfert 1 NGC 4051. arXiv: 0904.0251

Download references

Author information

Authors and Affiliations

  1. Department of Physics and Tsinghua Center for Astrophysics, Tsinghua University, Beijing, 100084, China

    Ling Zhu

  2. Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China

    ShuangNan Zhang

Authors
  1. Ling Zhu
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. ShuangNan Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to ShuangNan Zhang.

Additional information

Support by the Directional Research Project of the Chinese Academy of Sciences (Grant No. KJCX2-YW-T03), the National Natural Science Foundation of China (Grant Nos. 10821061, 10733010, 10725313) and the National Basic Research Program of China (Grant No. 2009CB824800).

Rights and permissions

Reprints and permissions

About this article

Cite this article

Zhu, L., Zhang, S. Diagnostics for the structure of AGNs’ broad line regions with reverberation mapping data: confirmation of the two-component broad line region model. Sci. China Phys. Mech. Astron. 53 (Suppl 1), 196–201 (2010). https://doi.org/10.1007/s11433-010-0057-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11433-010-0057-6

Keywords

Search

Navigation