  32 GHz observations with the Effelsberg 100-m telescope revealed a highly
polarized Galactic Centre filament: G0.087-0.087, running parallel to the
well-known Arc structure. It has a similar flat spectrum, but it is an order of
magnitude weaker. G0.087-0.087 is about 2.5' or 6.2 pc long and located at the
western boundary of the expanding molecular cloud G0.11-0.11. This unusual
cloud is also visible in X-rays and known to interact on its eastern periphery
with the Arc. Acceleration of highly relativistic particles at the surface of
G0.11-0.11 seems necessary to explain the properties of both structures. The
new filament supports previous findings on the existence of a strong poloidal
magnetic field throughout the Galactic Centre region.

Astrophysics