Table 10: Chemical diagnostics for YSO evolution.
NGC 7129 - FIRS 2 LkH $\alpha$ 234

SiO/C³⁴S $\sim$ 2 $\sim$ 0.1

CN/N₂H⁺ $\sim$ 1 $\sim$ 6

HCN/N₂H⁺ $\sim$ 0.4 $\sim$ 2

DCO⁺/HCO⁺ $\sim$ 0.008 $\sim$ 0.002

D₂CO/DCO⁺ $\sim$ 1 $\sim$ 10

**Table 10:** Chemical diagnostics for YSO evolution.
	NGC 7129 - FIRS 2	LkH $\alpha$ 234
SiO/C³⁴S	$\sim$ 2	$\sim$ 0.1
CN/N₂H⁺	$\sim$ 1	$\sim$ 6
HCN/N₂H⁺	$\sim$ 0.4	$\sim$ 2
DCO⁺/HCO⁺	$\sim$ 0.008	$\sim$ 0.002
D₂CO/DCO⁺	$\sim$ 1	$\sim$ 10

Source LaTeX | All tables | In the text

	1 Introduction
	2 Target selection and observational strategy
	3 Observations
	4 Analysis
	5 Results
	6 Deuterated compounds
	7 Discussion
	8 Summary and conclusions: Chemical clocks in intermediate-mass YSOs
	References
	Online Material