1. Talking About Spectrum Hou Saiyu 04/01/2014 Note: Four digital numbers referring to wavelength in unit of angstrom here

2. outline Introduction Properties Important spectrum in astronomy AGN spectrum

3. outline Introduction Properties Important spectrum in astronomy AGN spectrum

4. http://casswww.ucsd.edu/archive/public/tutorial/Stars.html

5. http://www2.keck.hawaii.edu/inst/hires/

6. outline Introduction Properties Important spectrum in astronomy AGN spectrum

7. Forbidden Lines Dipole radiation, selection rules Meta stable state Collision de-excitation Energy level life time Critical density Transition probabilities ~ 1 in 10 9

8. Forbidden Line Examples http://www.astr.ua.edu/keel/galaxies/emission.html Highest vacuum on earth <1000 atoms/cm3

9. Semi Forbidden Line eg. CIII]1909, NIII]1750, OIII]1663,NIV]1486 Electric dipole transition, but ΔS ≠0 CaI] λ6573 3 P 1  1 S 0 Transition probabilities ~1 in 10 6

10. Broadening Thermal Doppler Broadening Collision Broadening Rotational Broadening Δ λ/λ = v/c Natural Broadening Turbulent Broadening Zeeman Splitting … www.astronomy.gatech.edu/Courses/Phys3021/Lectures/pdf/Line_Broadening.pdf

11. Thermal Broadening http://astronomy.swin.edu.au/cosmos/t/thermal+doppler+broadening

12. Rotational Broadening http://astronomy.nju.edu.cn/~lixd/GA/AT4/AT404/HTML/AT40404.htm

13. Double Horned Line Profile Broad, asymmetric line profile with a sharp cutoff at high E

15. Broadening Estimate: For hydrogen atoms in the Solar photosphere (T=5770K), Hα656.3nm broadening 0.04nm The concept of Equivalent Width (EW) and Full width at half maxium （ FWHM ） http://www.mssl.ucl.ac.uk/www_astro/agn/agn_rixos.html

16. Searching For Exoplanets

17. Reverberation Mapping GM = f R BLR (ΔV) 2 ΔV measured from Doppler broadening of the gaseous emission lines Measuring Black Hole Mass http://ned.ipac.caltech.edu/level5/Sept09/Gaskell/Gaskell3.html

18. Narrow  low velocity Forbidden  low material density

19. outline Introduction Properties Important spectrum in astronomy AGN spectrum

20. Lyman α Forest http://www.astr.ua.edu/keel/agn/forest.html

21. Mg II absorption line Useful in finding galaxies with a background quasar http://astronomy.nmsu.edu/cwc/Research/MgIIreview/mgii-over.html

22. H 21 cm Line the birth of spectral-line radio astronomy Mapping the rotation curve of the Galaxy probe the "dark ages" from recombination to reionization SETI: searching for extraterrestrial civilizations http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/h21.html

23. [OIII] line strongest narrow line in AGNs at optical band high abundance of doubly charged oxygen ions isolated from other optical spectrum Useful in studying NLR [OIII] 5006.843/4958.911 intensity ratio [OIII] 5006.843/4958.911 intensity ratio

24. outline Introduction Properties Important spectrum in astronomy AGN spectrum

25. AGN Spectrum http://www.astro.caltech.edu/~george/ay127/Ay127_AGN.pdf

26. http://www.mpifr-bonn.mpg.de/1462499/padovani_lec1.pdf

27. http://www.astro.caltech.edu/~george/ay127/Ay127_AGN.pdf

28. Radio Galaxy/Seyfert 2 Quasar/Seyfert 1 Blazar http://en.wikipedia.org/wiki/Blazar

30. NLR: Keplerian orbital speeds of the clouds much smaller => lines are narrow http://abyss.uoregon.edu/~js/ast123/lectures/lec12.html Broad permitted lines Narrow Forbidden Lines Bright continuum from central engine Narrow permitted/forbidden Lines No bright continuum from the obscured central engine, except infrared and X-ray Spatially resolvable

31. Seyfert 1 & Seyfert 2 Osterbrock, D. Astrophysics of Gaseous Nebulae and Active Galactic Nuclei FWHMs ~5000km/s FWHMs ~500km/s Type 1.2, 1.5, 1.8 and 1.9 Seyfert galaxies, due to H spectrum

32. Spectrum of a typical quasar Lyα 1216 http://loke.as.arizona.edu/~ckulesa/camp/spectroscopy_examples.html Quasar=quasi-stellar radio source

33. Peterson, B.M. An Introduction to Active Galactic Nuclei

34. Why ν F ν ~ ν plot Power law spectrum F ν ~ ν -α In case α=1, ν F ν ~ ν diagram: horizontal In case α=0, ν F ν ~ ν diagram: proportional Quasar α=0~1 Convenient

35. BL Lac & OVVs

36. Hβ O[III] http://www.astr.ua.edu/keel/agn/spectra.html Featureless non-thermal continuum

37. SDSS Quasar Survey

39. Diagnostic Line Ratios R. Cid Fernandes et al. 2010

40. http://www.astro.caltech.edu/~george/ay127/Ay127_AGN.pdf

41. Variability of AGN in various spectral domains http://www.astr.ua.edu/keel/agn/vary.html Seyfert I

42. Thanks