1. 1 Black Hole Masses from Reverberation Mapping Bradley M. Peterson The Ohio State University Collaborators: M. Bentz, S. Collin, K. Dasyra, K. Denney, L. Ferrarese, K. Horne, S. Kaspi, T. Kawaguchi, C. Kuehn, D. Maoz, K. Metzroth, T. Minezaki, H. Netzer, C.A. Onken, R.W. Pogge, S.G. Sergeev, L. Tacconi, M. Vestergaard, A. Wandel, Y. Yoshii

2. 2 Key Points The line-width measure used for reverberation-based masses should be the line dispersion  line rather than FWHM. New observations are leading to improved results, better identification of systematics.

3. 3 Reverberation Mapping Results Reverberation lags have been measured for 36 AGNs, mostly for one or more Balmer lines, but in some cases for multiple lines. AGNs with lags for multiple lines show that highest ionization emission lines respond most rapidly  ionization stratification.

4. Evidence for a Virialized BLR Gravity is important –Broad-lines show virial relationship between size of line- emitting region and line width, r    2 –Yields measurement of black-hole mass M = f (c  cent  2 /G)  H   Other Lines based on Peterson & Wandel (1999)

5. 5 Determine scale factor f that matches AGNs to the quiescent-galaxy M BH -  *. relationship Current best estimate: f = 5.5 ± 1.8 Scaling factor is empirically determined This removes bias from the ensemble –Equal numbers of masses are overestimated and underestimated Calibration of the Reverberation Mass Scale Tremaine slope Ferrarese slope based on Onken et al. (2004) M = f (c  cent  2 /G)

6. 6 Physical Interpretation of f The Onken value is an average over the projection factors. Example: thin ring Aside: since unification requires 0  i  i max, simple disks without a polar component are formally ruled out.

7. 7 Characterizing Line Widths FWHM:  Trivial to measure  Less sensitive to blending and extended wings Line dispersion  line :  Well defined  Less sensitive to narrow-line components  More accurate for low-contrast lines 2.452.833.462.35 Some trivial profiles:

8. 8 Reverberation-mapped AGNs show broad range of FWHM/  line. Mass calibration is sensitive to which line-width measure is used! –Even worse, there is a bias with respect to AGN type (as reflected in the profiles) NLS1 + I Zw 1-type NGC 5548 H  Extreme examples

10. NGC 3227 NGC 3516 NGC 4051

11. I Zw 1 type NLS1

12. I Zw 1 type NLS1 NGC 5548

13. 13 Subset of the above for which host-galaxy luminosity can be removed accurately.

14. 14 Pop A Pop B similar to Sulentic et al. Pop 1 Pop 2 Collin et al. From Collin et al. (2006) Mean spectra RMS spectra

15. 15 Pop 1 Pop 2 Pop A Pop B similar to Sulentic et al. Collin et al. From Collin et al. (2006) Mean spectra RMS spectra f = 5.7  1.5 f = 5.4  2.7 f = 6.2  3.5 f = 4.7  1.1  line -based calibration

16. 16 Pop 1 Pop 2 Pop A Pop B similar to Sulentic et al. Collin et al. From Collin et al. (2006) Mean spectra RMS spectra f = 0.9  0.3 f = 2.2  1.2 FWHM-based f = 2.5  1.5 f = 0.8  0.2

17. 17 Line Width Measures Conclusion:  line is probably a less biased indicator of the mass than FWHM. Use of FWHM will lead us to underestimate the masses of NLS1s, I Zw 1-type objects, and narrower-line objects in general. –Can be corrected for empirically, however (see Collin, Kawaguchi, Peterson, & Vestergaard 2006).

18. 18 HST ACS images are used to decompose light into nuclear and starlight components. Effect is to flatten radius-luminosity relationship. Starlight components are stronger than previously supposed. Bentz et al. (2006)

19. Other New Developments New reverberation program on bright well- known Seyfert galaxies –Improve time sampling interval over original programs by as much as an order of magnitude in some cases. –Ultimate goal: a velocity- delay map for at least one line in one AGN. –Secondary goal: improve black hole mass measurements. Denney et al., in preparation Bentz et al., in preparation

20. 20 NGC 4151 Reanalyzed two UV monitoring data sets from IUE archive. UV and optical give consistent mass, 5  10 7 M  C IV (upper limit) Other UV lines New H  result Metzroth, Onken, & Peterson (2006) Bentz et al., in preparation

21. 21 NGC 4151 Moreover, the reverberation-based mass is consistent with the (highly uncertain) stellar dynamical mass based on long-slit spectra of the Ca II triplet. Onken, Valluri, et al., in preparation M rev

22. AGNs: Ca II triplet AGNs: CO bandhead (Dasyra & Tacconi) Quiescent: (Tremaine et al. 2002) The AGN M BH –  * Relationship

23. Onken calibration 

24. 24 Could Inclination Play a Role? Assume line width  V  (a 2 + sin 2 i ) 1/2 V kep Then f  M  / VP  1 / (a 2 + sin 2 i ) 1/2 M  / VP cannot be used to deduce inclination for individual sources because NGC 5548 shows that VP values can span a factor ~3. Collin et al. (2006)

25. 25 Could Inclination Play a Role? However, we can compare the OBSERVED cumulative distribution of M  / VP with that predicted by this simple model for various values of a. Reasonable agreement with simple model if only Population 1/A is used. –Implication is that at least some AGNs have narrow lines because of low inclination. Collin et al. (2006)

26. 26 Summary As the database on reverberation mapped AGNs improves, identification of systematic biases becomes easier. –Evidence that inclination plays a role. Reverberation-masses are less biased with respect to profile by using  line as the line-width measure. –FWHM /  line is sensitive to Eddington rate and inclination.

27. 27 What Do Line Widths Say About Masses?

28. 28 Brad’s gripe du jour: For fixed Eddington rate, more massive sources have larger line widths: –NLS1 criterion of FWHM < 2000 km s -1 omits higher-luminosity objects from class (“I Zw 1–type” objects, including, for example, 3C 273)