,
S. Guilloteau 
,
A. Dutrey 
,
P. Planesas 
,
J. Martin-Pintado 
Centro Astronómico de Yebes,
Apartado 148, E-19080 Guadalajara, Spain
Institut de Radio Astronomie Millimétrique,
300 rue de la Piscine,
F-38406 Saint Martin d'Hères, France 
2.6 mm continuum, with
angular resolution of 
(
4 10
pc at the
distance of L 1448, 300 pc). In the mapped area,
there are two partially overlapping outflows emerging from two
different continuum sources (L 1448/IRS3 and L 1448-mm).
The continuum maps are used to study the nature of the two exciting sources. The strong mm peak around L 1448/IRS3 is coincident in position with the VLA cm source L 1448N(B), and it likely is the source driving the outflow in the northern region. L 1448-mm is at the origin of the main outflow. The spectral energy distributions confirm that both sources (L 1448-mm and IRS3) are among the youngest known protostellar candidates (``Class 0" sources)
New details on the structure of the L 1448-mm outflow are revealed by
the CO observations. Weak line emission at extremely-high velocities
is detected along the jet which is at the axis of the outflow. Such
emission is associated with the molecular bullets detected with
single-dish telescopes. The jet is inclined at PA 
, and its
actual jet speed is in excess of 200 km.s
.
Limb-brightened cavities are detected at low CO velocities. The
cavities have a biconical morphology, suggesting that a bipolar nebula
is forming. The formation of the cavity is well explained in the
frame of models for jet-driven bipolar outflows, where the jet
entrains ambient molecular material through the propagation of large
bow-shocks which are able to disturb the ambient gas at long
transverse distances from the jet axis. A comparison of the CO data
with H
images at 2.12 
m provides further support to this
scenario.
The blue shifted lobe of the L 1448-mm outflow exhibits a continuous
bending that can be explained as a result of direct collision of the
two outflows in L 1448.