Left panel: a view of the CH₃OH maser features detected around W51–e2. Right panel: a zoom-in view of the boxed region of the left panel. The triangles symbols are the identified CH₃OH maser features scaled logarithmically according to their peak flux density (Table 1). The maser LSR radial velocity is indicated by color. A 6 Jy beam^-1 symbol is plotted for illustration in both panels. The linear polarization vectors, scaled logarithmically according to polarization fraction P_l, are overplotted. The two arrows indicate the direction of the bipolar outflow (PA ~ 150°; Keto & Klaassen 2008). The dashed line is the best linear fit of the CH₃OH maser features in the right panel (PA = 57°).