UV/Optical Detections of Candidate Tidal Disruption Events by GALEX and CFHTLS

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UV/Optical Detections of Candidate Tidal Disruption Events by GALEX and CFHTLS. Gezari et al. 2007. TexPoint fonts used in EMF. Read the TexPoint manual before you delete this box.:. SMBH Mass Function. How are SMBH masses derived? OIII kinematics – M- σ * - PowerPoint PPT Presentation

Transcript of UV/Optical Detections of Candidate Tidal Disruption Events by GALEX and CFHTLS

GEZARI ET AL. 2007

UV/Optical Detections of Candidate Tidal Disruption

Events by GALEX and CFHTLS

SMBH Mass Function

How are SMBH masses derived? OIII kinematics – M-σ*

Relations with bulge mass / luminosity – M-L*

Reverberation mapping Only good for nearby (or bright) stuff Only good if active

Outstanding questions How do they coevolve with their hosts? How does mass scale with redshift?

Tidal Disruption

Magorrian & Tremaine predict 103-105 yrs between

events For too large a mass, RT < RS

Can use tD to constrain MBH

Aquire tD from power-law decay in consumption rate

(n=5/3)

Previous Candidates

NGC 4552 has a “mini-AGN” In 1995 experienced UV flare L ~ 1039 ergs/s

ROSAT (1990-91) detected several soft X-ray flares L ~ 1042 – 1044 ergs/s No previous AGN activities in hosts Derived rate of 10-5 yr-1 per galaxy

Agrees with Magorrian & Tremaine rate

Searching for New Candidates

GALEX DIS Optical counterparts in CFHTLS 80 deg2 coverage (0.02 sr)

Rule out hard X-ray emitters (AGNs) Must rule out type II SNe Fit to power law decay (n=5/3, monotonic) Find tD => MBH

Ruled Out UV Outbursts

Ruled Out Type II SNe

Candidate D1-9

BC03 fits early-type galaxy at z=0.326

Candidate D1-9

Candidate D3-13

Candidate D3-13

Black Hole Masses

Spectral Energy Densities

Things I Did Not Cover

The full energy argument getting to MBH Expected detection rates