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SUMMARY:Variability of methanol maser in the massive star formation region
 s
DTSTART;VALUE=DATE-TIME:20110714T150000Z
DTEND;VALUE=DATE-TIME:20110714T170000Z
DTSTAMP;VALUE=DATE-TIME:20260715T045328Z
UID:indico-contribution-5109@events.saip.org.za
DESCRIPTION:Speakers: jabulani Paul maswanganye (Wits University/HartRAO)\
 nStar formation constitutes one of the basic problems of astrophysics due 
 to the fact that stars are fundamental objects of astronomy. Shu et al. (1
 987) reviews the theory of low mass star formation from the molecular clou
 d via accretion disk-outflow. The formation of high mass stars is still no
 t well understood. They may also be formed through accretion disk plus out
 flow (Shu et al. 1987) or by collision-coalescence  which was proposed by 
 Wolfire \\& Cassinelli (1987) and Bonnell  et al. (1998)\, but most observ
 ations support the accretion disk-outflow model.\nThe brightest methanol m
 asers occur at 6668 MHz and 12178 MHz and  are found in the star forming r
 egions  containing very young massive protostars even before the formation
  of  an ultracompact HII region (Longmore et al. 2007). These masers serve
  as useful tools to study these regions.\nThe poster will be on the analys
 is of the time series of 6668 MHz and 12178 MHz methanol maser emission li
 nes in some of the sources which were showing periodic variations in monit
 oring before the 26 meter Hartebeesthoek Radio Astronomy Observatory (Hart
 RAO) Telescope bearing failure in 2008. After the telescope was repaired i
 n 2010\, the programme to monitor these sources was restarted. These two m
 ethanol emission lines are radiatively pumped which implies that their var
 iability could be due to the decrease or increase in the seed photons at t
 he radio frequency\, or the infrared radiation field that pumps the masers
 . Since there has been a two year gap in the monitoring program of these s
 ources\, we want to establish whether the periodic variations continue. Su
 ch periodic behaviour  has not been seen in  other maser species in star f
 orming regions\, so it can provide new insights into what is happening in 
 these regions.\n\nhttps://events.saip.org.za/event/7/contributions/5109/
LOCATION: Asteria
URL:https://events.saip.org.za/event/7/contributions/5109/
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