  A new methanol maser line 6(-1)-5(0)E at 133 GHz was detected with the 12-m
Kitt Peak radio telescope using remote observation mode from Moscow. Moderately
strong, narrow maser lines were found in DR21(OH), DR21-W, OMC-2, M8E, NGC2264,
L379, W33-Met. The masers have similar spectral features in other transitions
of methanol-E at 36 and 84 GHz, and in transitions of methanol-A at 44 and 95
GHz. All these are Class I transitions, and the new masers also belong to Class
I. In two other methanol transitions near 133 GHz, 5(-2)-6(-1)E and
6(2)-7(1)A+, only thermal emission was detected in some sources. Several other
sources with wider lines in the transition 6(-1)-5(0)E also may be masers,
since they do not show any emission at the two other methanol transitons near
133 GHz. These are NGC2071, S231, S255, GGD27, also known as Class I masers.
The ratio of intensities and line widths of the 133 GHz masers and 44 GHz
masers is consistent with the saturated maser model, in which the line
rebroadening with respect to unsaturated masers is suppressed by cross
relaxation due to elastic collisions.
