We present Karl G. Jansky Very Large Array ( VLA ) observations of the CO ( 2 - 1 ) line emission towards three far-infrared luminous quasars at z \sim 6 : SDSS J231038.88 + 185519.7 and SDSS J012958.51 - 003539.7 with \sim 0 \farcs 6 resolution and SDSS J205406.42 - 000514.8 with \sim 2 \farcs 1 resolution .
All three sources are detected in the CO ( 2 - 1 ) line emission – one source is marginally resolved , and the other two appear as point sources .
Measurements of the CO ( 2 - 1 ) line emission allow us to calculate the molecular gas mass even without a CO excitation model .
The inferred molecular gas masses are ( 0.8 - 4.3 ) \times 10 ^ { 10 } M _ { \odot } .
The widths and redshifts derived from the CO ( 2 - 1 ) line are consistent with previous CO ( 6 - 5 ) and [ C ii ] measurements .
We also report continuum measurements using the Herschel for SDSS J231038.88 + 185519.7 and SDSS J012958.51 - 003539.7 , and for SDSS J231038.88+185519.7 , data obtained at \sim 140 and \sim 300 GHz using the Atacama Large Millimeter/submillimeter Array ( ALMA ) .
In the case of SDSS J231038.88+185519.7 , we present a detailed analysis of the spectral energy distribution and derive the dust temperature ( \sim 40 K ) , the dust mass ( \sim 10 ^ { 9 } M _ { \odot } ) , the far-infrared luminosity ( 8 - 1000 \mu m ; \sim 10 ^ { 13 } L _ { \odot } ) and the star formation rate ( 2400 - 2700 M _ { \odot } yr ^ { -1 } ) .
Finally , an analysis of the photo-dissociation regions associated with the three high redshift quasars indicates that the interstellar medium in these sources has similar properties to local starburst galaxies .