Detection of new methanol maser transitions associated with G358.93-0.03
  We report the detection of new 12.178, 12.229, 20.347, and 23.121 GHz
methanol masers in the massive star-forming region G358.93-0.03, which are
flaring on similarly short timescales (days) as the 6.668 GHz methanol masers
also associated with this source. The brightest 12.178 GHz channel increased by
a factor of over 700 in just 50 d. The masers found in the 12.229 and 20.347
GHz methanol transitions are the first ever reported and this is only the
fourth object to exhibit associated 23.121 GHz methanol masers. The 12.178 GHz
methanol maser emission appears to have a higher flux density than that of the
6.668 GHz emission, which is unusual. No associated near-infrared flare
counterpart was found, suggesting that the energy source of the flare is deeply
embedded.
