Centennial Honors College
Western Illinois University
Undergraduate Research Day 2014
Poster Presentation
Time Delay Between Molecular Maser Flares of
Methanol and Hydroxyl
Daniel M Halbe
Faculty Mentor: Esteban D. Araya
Physics
In 2012, Al-Marzouk and collaborators reported the detection of a hydroxyl (OH) maser
toward the massive star forming region IRAS 18566+0408. This source is the only
region where periodic flares of formaldehyde and methanol masers have been seen.
The data reported by Al-Marzouk et al. (2012) suggest a three month delay between the
methanol and formaldehyde maser flares with respect to OH flares. Here we report
follow-up observations with the Arecibo Telescope to confirm the occurrence of OH
flares and the delay with respect to methanol flares. We detected a new flare event and
confirmed the delay between the flare peaks. The delays could be caused by the 3-D
distribution of the masers with respect to the source that triggers the variability.