We present HST STIS observations of the galaxy NGC 4382 ( M85 ) and axisymmetric models of the galaxy to determine mass-to-light ratio ( \Upsilon _ { V } ) and central black hole mass ( M _ { \mathrm { BH } } ) .
We find \Upsilon _ { V } = 3.74 \pm 0.1 { { M } } _ { \scriptscriptstyle \odot } / { { L } } _ { % \scriptscriptstyle \odot } and M _ { \mathrm { BH } } = 1.3 ^ { +5.2 } _ { -1.2 } \times 10 ^ { 7 } { { M } } _ { \scriptscriptstyle \odot } at an assumed distance of 17.9 Mpc , consistent with no black hole .
The upper limit , M _ { \mathrm { BH } } < 9.6 \times 10 ^ { 7 } { { M } } _ { \scriptscriptstyle \odot } ( 2 \sigma ) or M _ { \mathrm { BH } } < 1.4 \times 10 ^ { 8 } ( 3 \sigma ) is consistent with the current M – \sigma relation , which predicts M _ { \mathrm { BH } } = 8.8 \times 10 ^ { 7 } { { M } } _ { \scriptscriptstyle \odot } at \sigma _ { e } = 182 ~ { } \mathrm { km~ { } s ^ { -1 } } , but low for the current M – L relation , which predicts M _ { \mathrm { BH } } = 7.8 \times 10 ^ { 8 } { { M } } _ { \scriptscriptstyle \odot } at L _ { V } = 8.9 \times 10 ^ { 10 } { L } _ { { \scriptscriptstyle \odot } ,V } . HST images show the nucleus to be double , suggesting the presence of a nuclear eccentric stellar disk , in analogy to the Tremaine disk in M31 .
This conclusion is supported by the HST velocity dispersion profile .
Despite the presence of this non-axisymmetric feature and evidence of a recent merger , we conclude that the reliability of our black hole mass determination is not hindered .
The inferred low black hole mass may explain the lack of nuclear activity . \pdfstringdef \BKM @ title Abstract