Lefloch, BertrandBertrandLeflochVastel, C.C.VastelViti, S.S.VitiJimenez-Serra, I.I.Jimenez-SerraCODELLA, CLAUDIOCLAUDIOCODELLAPODIO, LINDALINDAPODIOCeccarelli, C.C.CeccarelliMendoza, E.E.MendozaLepine, J. R. D.J. R. D.LepineBachiller, R.R.Bachiller2020-09-112020-09-1120160035-8711http://hdl.handle.net/20.500.12386/27339As part of the Large Program Astrochemical Surveys At IRAM, we have used the IRAM 30 m telescope to lead a systematic search for the emission of rotational transitions of P-bearing species between 80 and 350 GHz towards L1157-B1, a shock position in the solar-type star-forming region L1157. We report the detection of several transitions of PN and, for the first time, of pre-biotic molecule PO. None of these species are detected towards the driving protostar of the outflow L1157-mm. Analysis of the line profiles shows that PN arises from the outflow cavity, where SiO, a strong shock tracer, is produced. Radiative transfer analysis yields an abundance of 2.5 × 10<SUP>-9</SUP> and 0.9 × 10<SUP>-9</SUP> for PO and PN, respectively. These results imply a strong depletion (≈100) of phosphorus in the quiescent cloud gas. Shock modelling shows that atomic N plays a major role in the chemistry of PO and PN. The relative abundance of PO and PN brings constraints both on the duration of the pre-shock phase, which has to be ∼10<SUP>6</SUP> yr, and on the shock parameters. The maximum temperature in the shock has to be larger than 4000 K, which implies a shock velocity of 40 km s<SUP>-1</SUP>.STAMPAenArticle10.1093/mnras/stw19182-s2.0-84994514562000385231600035https://academic.oup.com/mnras/article/462/4/3937/25898972016MNRAS.462.3937LFIS/05 - ASTRONOMIA E ASTROFISICA