Title: Observing the Orion-KL region with ALMA

 

Speaker: Dr. Laurent Pagani (The National Center for Scientific Research & Observatoire de Paris, France)

 

Time: 15:30pm 20th Oct. 2017 (Friday)

 

Vanue: R521, IoA, 2nd General Building 綜二館R521

 

Abstract:

Orion is the closest massive star forming region we can observe from the Earth. At a distance of ~400 pc (1200 light-years), it is hardly three times further away than the closest low mass star forming regions like Taurus, Rho Ophiuchi, etc. Despite its closeness, it harbours a highly structured core of 15’’ diameter only, which single dish radio-telescopes can hardly resolve. Inside the core the various structures have different properties and since they cannot be separated in surveys like the Herschel survey, it is difficult to interpret the thousands of molecular lines detected towards this object. While this structure has been long known from infrared observations, it is only recently that interferometers have been able to look at this source. In particular, the advent of ALMA is bringing the huge power of its thousands of baselines, large number of receivers and large bandwidth coverage to get a very crisp image with little noise and deformation of this source and separate all the components.

During this talk, I will present the radio emission of molecules, the principle of interferometers and their difference with ordinary radio telescopes, and some of the recent results we have obtained with ALMA towards this source which give a new picture of its history and dynamics.