EVN imaging of methanol masers towards massive protostars Anna Bartkiewicz Marian Szymczak Huib Jan...

EVN imaging of methanol masers towards massive protostars

Anna Bartkiewicz Marian Szymczak

Huib Jan van Langevelde

8th EVN Symposium Torun 2006

The ring G23.657-00.127:

Ellipse: e=0.38133 mas x 123 masi.e.1400 AUx 1300 AUat 10.5 kpcor700 AUx 630 AUat 5.1 kpc

A disc at i=67 deg?Vlsr=Vrot * cos i * cos A

A(deg)

VLBA observations on November 2005:

12.2 GHz

6.7 GHz?

IRAS2MASSMSX

540 Kand 80 K(Walsh et al. 1999)

Arc-like sources: G24.541+00.312 & G23.707-00.198

370(560) AU

370(750) AU

Model by Moscadelli, Cesaroni & Rioja, 2000

Complex distribution:

Conclusions:

• new structures of 6.7 GHz methanol masers were detected at maps with milliarcsecond resolution (esp. ring),

• the arc-like masers were explained well by the bipolar outflow model,

• complex structures arose likely through propagation of a few shock fronts driven by protostars.

Future work:• further investigation of the ring G23.657-00.127 including

proper motion studies and measurements of the parallax,

• high resolution studies of radio continuum and infraredcounterparts.