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Description
Gas plays a major role in the dynamical evolution of young stellar objects (YSOs). Its interaction with the dust is the key to our understanding planet formation later on in the protoplanetary disc stage. Studying the gas content is therefore a crucial step towards understanding YSO and planet formation. Such a study can be made through spectroscopic observations of emission lines in the far-infrared, where some of the most important gas coolants emit, such as the [OI] ^3^P_1_-^3^P_2_ transition at 63.18 microns. We provide a compilation of observations of far-IR lines in 362 young stellar objects covering all evolutionary stages, from Class 0 to Class III with debris discs. In the present paper we focus on [OI] and o-H_2_O emission at 63 microns. We have retrieved all the available Herschel-PACS spectroscopic observations at 63 microns that used the dominant observing mode, the chop-nod technique. We provide measurements of line fluxes for the [OI] ^3^P_1_-^3^P_2_ and o-H_2_O 8_08_-7_17_ transitions at 63 microns computed using different methods. Taking advantage of the PACS IFU, we check for spatially extended emission and further study the presence of multiple dynamical components in line emission. The final compilation consists of line and continuum fluxes at 63 microns for a total of 362 young stellar objects (YSOs). We detected [OI] line emission at 63 microns in 194 sources out of 362, and line absorption in another five sources. o-H_2_O was detected in 42 sources. We find evidence of extended [OI] emission in 77 sources, and detect 3sigma residual emission in 71 of them. The number of sources showing extended emission decays from Class 0 to Class II. We also looked for different components contributing to the line emission, and found evidence for multiple components in 30 sources. We explored correlations between line emission and continuum emission and find a clear correlation between WISE fluxes from 4.6 to 22 microns and [OI] line emission. We conclude that the observed emission is typically a combination of disc/envelope and jet emission.
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