the b1 shock in the l1157 outflow as seen at high spatial resolution m. benedettini, s. viti, c....

The B1 shock in the L1157 outflow as seen at high spatial

resolutionM. 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

Benedettini et al. 2006

3 mm data

Plateau de Bure 2 mm data

Codella et al. 2009

Multi-velocity components along some clumps

Compact (3”-6”) high velocity clumps

B0e-HV2 v= -16 km/s

B1a-HVv= -12 km/s B1b-HV

v= -4 km/s

B0e-HV1 v= -6 km/s

Comparison between PdB spectrum (blue) and IRAM-30m spectrum (black)

CS (2-1) CS (3-2)

Flux filtering at all velocity No filtering for v<6 km/s

Largest sensible structure 14 ” HV clumps do not suffer flux filtering

LVG modeling of CS (2-1) and (3-2) of HV clumps

Constraint of the gas density!

5x103 ≤n(H2)≤ 5x105 cm3

T= 55 -132 K from Codella et al. 2009

Chemical modelChemical code (UCL_CHEM, Viti et al. 2004)

+

parametric C-type shock (Jimenez-Serra 2008)

Pre-shock density >104 cm3

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”

Possible direction of the jetB0e-

HV2B0e-HV2

B0e-HV1

B0e-HV1

CS (3-2) first moment

Outflow cavity

Outflow cavity

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)