1. The B1 shock in the L1157 outflow as seen at high spatial resolution M. Benedettini, S. Viti, C. Codella, F. Gueth, A. Gomez-Ruiz, R. Bachiller, M. Beltran, G. Busquet, C. Ceccarelli, B. Lefloch Accepted by MNRAS Herscehl, CHESS meeting Roma, 11-13 September 2013

2. Benedettini et al. 2006 3 mm data Plateau de Bure 2 mm data Codella et al. 2009

3. Multi-velocity components along some clumps

4. Compact (3”-6”) high velocity clumps B0e-HV2 v= -16 km/s B1a-HV v= -12 km/s B1b-HV v= -4 km/s B0e-HV1 v= -6 km/s

5. Comparison between PdB spectrum (blue) and IRAM-30m spectrum (black) CS (2-1)CS (3-2) Flux filtering at all velocityNo filtering for v<6 km/s Largest sensible structure 14 ” HV clumps do not suffer flux filtering

6. LVG modeling of CS (2-1) and (3-2) of HV clumps Constraint of the gas density! 5x10 3 ≤n(H 2 )≤ 5x10 5 cm 3 T= 55 -132 K from Codella et al. 2009

7. Chemical model Chemical code (UCL_CHEM, Viti et al. 2004) + parametric C-type shock (Jimenez-Serra 2008)  Pre-shock density >10 4 cm 3  30 % of CO depleted in grain during the core formation  Maximum shock temperature ~ 4000 K that implies shock velocity 40 km/s Used by Viti et al 2011 for modelling H2O and NH3 5”

8. Possible direction of the jet B0e- HV2 B0e- HV1 CS (3-2) first moment Outf low cavi ty On the origin of the HV clumps external clumps pushed by the expanding outflow cavity? clumps produced by the shock? the jet? VLA proposal to detect the radio jet (Busquet et al)