We present results of a comprehensive multi-frequency study of the radio galaxy B3 J2330+3927 .
The 1 \aas@@fstack { \prime \prime } 9 wide radio source , consisting of 3 components , is bracketed by 2 objects in our Keck K - band image .
Optical and near-IR Keck spectroscopy of these two objects yield z = 3.087 \pm 0.004 .
The brightest ( K = 18.8 ) object has a standard type II AGN spectrum , and is the most likely location of the AGN , which implies a one-sided jet radio morphology . Deep 113 GHz observations with the IRAM Plateau de Bure Interferometer reveal CO J = 4 - 3 emission , which peaks at the position of the AGN .
The CO line is offset by 500 { km s ^ { -1 } } from the systemic redshift of the AGN , but corresponds very closely to the velocity shift of an associated H I absorber seen in Ly \alpha .
This strongly suggests that both originate from the same gas reservoir surrounding the AGN host galaxy .
Simultaneous 230 GHz interferometer observations find a \sim 3 \times lower integrated flux density when compared to single dish 250 GHz observations with MAMBO at the IRAM 30m telescope .
This can be interpreted as spatially resolved thermal dust emission at scales of 0 \aas@@fstack { \prime \prime } 5 to 6″ . Finally , we present a \tau < 1.3 % limit to the H I 21 cm absorption against the radio source , which represents the seventh non-detection out of 8 z > 2 radio galaxies observed to date with the WSRT . We present mass estimates for the atomic , neutral , and ionized hydrogen , and for the dust , ranging from M ( { H \textsc { I } } ) = 2 \times 10 ^ { 7 } M _ { \odot } derived from the associated H I absorber in Ly \alpha up to M ( { H } _ { 2 } ) = 7 \times 10 ^ { 10 } M _ { \odot } derived from the CO emission .
This indicates that the host galaxy is surrounded by a massive reservoir of gas and dust .
The K - band companion objects may be concentrations within this reservoir , which will eventually merge with the central galaxy hosting the AGN .