Gas-Rich Galaxy Pair Unveiled in the Lensed Quasar 0957+561
P. Planesas,
1*
J. Martín-Pintado,
1
R. Neri,
2
L. Colina
3
Molecular gas in the host galaxy of the lensed quasar 0957+561 (QSO
0957+561) at the redshift of 1.41 has been detected in the carbon
monoxide (CO) line. This detection shows the extended nature of the
molecular gas distribution in the host galaxy and the pronounced
lensing effects due to the differentially magnified CO luminosity at
different velocities. The estimated mass of molecular gas is about
4 × 109 solar masses, a molecular gas mass typical of
a spiral galaxy like the Milky Way. A second, weaker component of CO is
interpreted as arising from a close companion galaxy that is rich in
molecular gas and has remained undetected so far. Its estimated
molecular gas mass is 1.4 × 109 solar masses, and its
velocity relative to the main galaxy is 660 kilometers per second. The
ability to probe the molecular gas distribution and kinematics of
galaxies associated with high-redshift lensed quasars can be used to
improve the determination of the Hubble constant
H0.
1 Observatorio Astronómico Nacional (IGN),
Apartado 1143, E-28800 Alcalá de Henares, Spain.
2 Institut de Radio Astronomie Millimétrique, F-38460
Saint Martin d'Hères, France.
3 Instituto de
Física de Cantabria (CSIC-UC), Facultad de Ciencias, E-39005
Santander, Spain.
*
To whom correspondence should be addressed. E-mail: planesas{at}oan.es
