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A Heartless Globular in Virgo?. Gaseous Nebulae Fall 2008 Gregory Shields. Stephen Zepf+ 2008 arXiv:0805.2952 “Very Broad [O III] …Globular Cluster RZ 2100 and Implications for … Black Hole X-ray Source”. SUMMARY Dynamical arguments involving high speed [O III] emission
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A Heartless Globular in Virgo? Gaseous Nebulae Fall 2008 Gregory Shields
Stephen Zepf+ 2008 arXiv:0805.2952 “Very Broad [O III] …Globular Cluster RZ 2100 and Implications for … Black Hole X-ray Source” SUMMARY Dynamical arguments involving high speed [O III] emission rule out presence of black hole consistent with universal M-L relation.
[O III] Analysis FWHM 2000 km/s L = 1037.1 erg/s Min. Volume = 1048.8 cm-3 [O/H]-1 Min. radius = 10^16.1 cm [O/H]^-1/3 Max. orb. vel. = (10 km/s) M-31/2 [O/H]1/6 Can’t be orbital motion ==> Must be outflow
Dynamical Argument -- Outflow requires near Eddington limit -- LX = 1039.6 erg/s ==> MBH ~ 10 Msun -- Mcluster = 106.3 Msun M-M* ==> MBH ~ 900 Msun M-sigma ==> Mbh ~ 5000 Msun -- IMBH would have ejected stellar mass BH, so can’t be there. -- Other globulars claimed to obey M-sigma (Gebhardt, et al.)