2001A&A...372..899B


C.D.S. - SIMBAD4 rel 1.7 - 2020.10.24CEST18:27:31

2001A&A...372..899B - Astronomy and Astrophysics, volume 372, 899-912 (2001/6-4)

Chemically active outflow L 1157.

BACHILLER R., PEREZ GUTIERREZ M., KUMAR M.S.N. and TAFALLA M.

Abstract (from CDS):

We present millimeter-wave maps of the L 1157 bipolar outflow in several molecular emission lines. The CO emission traces the bulk of the outflowing gas in the red and blue shifted lobes displaying a remarkable S-shaped symmetry indicating the presence of a precessing jet. We determine the physical characteristics of the CO flow and show evidence for 3 or 4 independent episodes of mass ejection from the source. Molecules such as C3H2, N2H+ and DCO+ are seen to be abundant only in the quiescent medium, and result to be the best tracers of the high-density core surrounding the driving source of the outflow. Other molecules (SiO, CH3OH, H2CO, HCN, CN, SO, SO2) are abundant in the outflow lobes, but exhibit strong emission gradients. Multiline observations of some species indicate that these gradients are not simply due to excitation effects, but are caused by an actual stratification in the chemical composition of the shocked molecular gas. Shock tracers such as SiO, CH3OH, and sulphur-bearing molecules result to be the most promising candidates as potential chemical clocks to study the evolution of outflows. The characteristics of the L 1157 outflow, when compared to those of other outflows from Class0 sources, indicate that L 1157 is the prototype of a category of bipolar outflows around Class0 protostars which we denominate ``chemically active outflows''.

Abstract Copyright:

Journal keyword(s): stars: formation - interstellar medium: individual objects: L 1157 - interstellar medium: jets and outflows - interstellar medium: molecules

Simbad objects: 12

goto Full paper

goto View the reference in ADS

Number of rows : 12

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 2MASS J03291177+3126095 Y*O 03 29 11.7727409461 +31 26 09.333798840           ~ 23 0
2 HH 243 HH 05 32 27.83 +12 53 14.6   17.0       ~ 116 0
3 HH 34 HH 05 35 31.30 -06 28 43.0     16     ~ 469 2
4 [TB95] R2 red 20 38 55 +68 05.0           ~ 10 0
5 [TB95] R0 red 20 39 00 +68 03.3           ~ 14 0
6 [TB95] R1 red 20 39 00 +68 04.5           ~ 13 0
7 HH 375 Y*O 20 39 06.2 +68 02 15           ~ 161 0
8 LDN 1157 DNe 20 39 06.4 +68 02 13           ~ 493 0
9 [DE95] LDN 1157 B2 out 20 39 09.3 +68 00 44           ~ 61 0
10 [DE95] LDN 1157 B1 out 20 39 11 +68 01.3           ~ 188 0
11 [TB95] B0 blu 20 39 11 +68 01.7           ~ 21 0
12 V* PV Cep Or* 20 45 53.9537161790 +67 57 38.678052612   19.27 17.46 15.98 14.60 A5 254 3

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2001A&A...372..899B and select 'bookmark this link' or equivalent in the popup menu


2020.10.24-18:27:31

© Université de Strasbourg/CNRS

    • Contact