EDP Sciences logo
Subscriber Authentication Point
Search
Menu
Home All issues Volume 565 (May 2014) A&A, 565 (2014) A64 Full HTML
Free Access

Table 2

Gas physical conditions, column density, and fractional abundances of CO and molecular ions.

Species Cmp T kin n H2 N species X = Nspecies/NH2
(K) (cm-3) (cm-2)
COa g 1 210 ≥106 9 × 1015 10-4
g 2 60–80 ≥105 9 × 1016 10-4
g 3 20 ≥105 1 × 1017 10-4
HCO+ g 1 210b 106–107b 1–3 × 1012 1–3 × 10-8
g 2 60 105 6 × 1012 7 × 10-9
N2H+c g2/g3 20–70c – 0.4–8 × 1012 0.4–8 × 10-9
HOCO+ g2/g3 35 104 1 × 1012 1 × 10-9
SO+d g2/g3 25d – 7 × 1011 8 × 10-10
HCS+ g 2 80 8 × 105 6 × 1011 7 × 10-10
g 3 20e 105e 3 × 1011 3 × 10-10

Notes.

(a)

Lefloch et al. (2012). The fractional abundance of CO is assumed.

(b)

Tkin and nH2 in g1 are assumed to be as derived from CO.

(c)

NN2H+, XN2H+ estimated by Codella et al. (2013) assuming LTE at Tkin = 20−70 K and a source size of ~20 − 25′′ as inferred from CO.

(d)

Since no collisional coefficients are available, we apply an LTE analysis assuming that the emission originates in the extended outflow cavities (g2,g3). At difference with the other ions, the estimated temperature is thus an excitation temperature, Tex.

(e)

Tkin and nH2 in g3 are assumed to be as derived from CO. This assumption relies on the similarity of CO and HCS+ profiles at low velocities and on the results of the LVG analysis (see text).

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.