A Masing Event in NGC6334I: Contemporaneous Flaring of Hydroxyl,
  Methanol and Water Masers
  As a product of the maser monitoring program with the 26m telescope of the
Hartebeesthoek Radio Astronomy Observatory (HartRAO), we present an
unprecedented, contemporaneous flaring event of 10 maser transitions in
hydroxyl, methanol, and water that began in 2015 January in the massive
star-forming region NGC6334I in the velocity range -10 to -2 km/s. The 6.7 GHz
methanol and 22.2 GHz water masers began flaring within 22 days of each other,
while the 12.2 GHz methanol and 1665 MHz hydroxyl masers flared 80 and 113 days
later respectively. The 1665 MHz, 6.7 GHz, and 22.2 GHz masers have all
remained in their flared state for nearly 3 years. The brightest flaring
components increased by factors of 66, 21, 26, and 20 in the 12.2 and 6.7 GHz
methanol, 1665 MHz hydroxyl and 22.2 GHz water maser transitions respectively;
some weaker components increased by up to a factor of 145. We also report new
maser emission in the 1720, 6031, and 6035 MHz OH lines and the 23.1 GHz
methanol line, along with the detection of only the fifth 4660 MHz OH maser. We
note the correlation of this event with the extraordinary (sub)millimeter
continuum outburst from the massive protostellar system NGC6334I-MM1 and
discuss the implications of the observed time lags between different maser
velocity components on the nature of the outburst. Finally, we identify two
earlier epoch maser flaring events likely associated with this object, which
suggest a recurring accretive phenomenon that generates powerful radiative
outbursts.
