Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Far infrared CO and H$_2$O emission in intermediate-mass protostars   Intermediate-mass young stellar objects (YSOs) provide a link to understand
how feedback from shocks and UV radiation scales from low to high-mass star
forming regions. Aims: Our aim is to analyze excitation of CO and H$_2$O in
deeply-embedded intermediate-mass YSOs and compare with low-mass and high-mass
YSOs. Methods: Herschel/PACS spectral maps are analyzed for 6 YSOs with
bolometric luminosities of $L_\mathrm{bol}\sim10^2 - 10^3$ $L_\odot$. The maps
cover spatial scales of $\sim 10^4$ AU in several CO and H$_2$O lines located
in the $\sim55-210$ $\mu$m range. Results: Rotational diagrams of CO show two
temperature components at $T_\mathrm{rot}\sim320$ K and
$T_\mathrm{rot}\sim700-800$ K, comparable to low- and high-mass protostars
probed at similar spatial scales. The diagrams for H$_2$O show a single
component at $T_\mathrm{rot}\sim130$ K, as seen in low-mass protostars, and
about $100$ K lower than in high-mass protostars. Since the uncertainties in
$T_\mathrm{rot}$ are of the same order as the difference between the
intermediate and high-mass protostars, we cannot conclude whether the change in
rotational temperature occurs at a specific luminosity, or whether the change
is more gradual from low- to high-mass YSOs. Conclusions: Molecular excitation
in intermediate-mass protostars is comparable to the central $10^{3}$ AU of
low-mass protostars and consistent within the uncertainties with the high-mass
protostars probed at $3\cdot10^{3}$ AU scales, suggesting similar shock
conditions in all those sources.

1
The categories of this paper are: cs
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg