We present high-resolution VLA observations of the molecular gas in the host galaxy of the highest redshift quasar currently known , SDSS J1148+5251 ( z=6.42 ) .
Our VLA data of the CO ( 3–2 ) emission have a maximum resolution of 0.17 ^ { \prime \prime } \times 0.13 ^ { \prime \prime } ( \leq 1 kpc ) , and enable us to resolve the molecular gas emission both spatially and in velocity .
The molecular gas in J1148+5251 is extended to a radius of 2.5 kpc , and the central region shows 2 peaks , separated by 0.3 ^ { \prime \prime } ( 1.7 kpc ) .
These peaks account for about half of the total emission , while the remainder is more extended .
Each of these unresolved peaks contains a molecular gas mass of \sim 5 \times 10 ^ { 9 } M _ { \odot } ( similar to the total mass found in nearby ULIRGS ) and has an intrinsic brightness temperature of \sim 35 K ( averaged over the 1 kpc-sized beam ) , comparable to what is found in nearby starburst centers .
Assuming that the molecular gas is gravitationally bound , we estimate a dynamical mass of \sim 4.5 \times 10 ^ { 10 } M _ { \odot } within a radius of 2.5 kpc ( \sim 5.5 \times 10 ^ { 10 } M _ { \odot } if corrected for a derived inclination of i \sim 65 ^ { \circ } ) .
This dynamical mass estimate leaves little room for matter other than the detected molecular gas , and in particular the data are inconsistent with a \sim 10 ^ { 12 } M _ { \sun } stellar bulge which would be predicted based on the M _ { BH } - \sigma _ { bulge } relation .
This finding may indicate that black holes form prior to the assembly of the stellar bulges and that the dark matter halos are less massive than predicted based on the black hole/bulge mass relationship .