Description
No chiral molecule has been detected in the interstellar medium (ISM) so far. A good candidate for an interstellar detection is 2-aminopropionitrile (CH_3_CH(NH_2_)CN), a chiral and the simplest molecule with a C_3_H_6_N_2_ formula. The first member of this series, aminoacetonitrile (H_2_NCH_2_CN), was recently detected, demonstrating that at least one aminonitrile exist in the ISM. Experimental spectra of 2-aminopropionitrile have been recorded in the microwave and sub-mm energy range (8-80GHz, 150-660GHz). An unbiased spectral survey of the 80-116GHz atmospheric window performed with the IRAM 30m telescope is used to search for this molecule in the hot core Sgr B2(N). This survey is analysed in the local thermodynamical equilibrium (LTE) approximation. The emission of 2-aminopropionitrile is modeled simultaneously with the emission of all molecules known in Sgr B2(N), which allows to properly take into account line blending and avoid mis-assignments. Only 10 groups of transitions of 2-aminopropionitrile are not severely affected by line blending in the Sgr B2(N) spectrum. Six of them could be considered as tentatively detected but the LTE predictions of the four remaining groups are not (or only marginally) consistent with the observed spectrum. Therefore, only an upper limit of 1.7*10^16^cm^-2^ can be securely derived for the column density of 2-aminopropionitrile toward Sgr B2(N).
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