%0 Journal Article %T Abundance of HOCO+ and CO2 in the outer layers of the L1544 prestellar core %+ Institut de recherche en astrophysique et planétologie (IRAP) %+ Institut de Planétologie et d'Astrophysique de Grenoble (IPAG) %A Vastel, C. %A Ceccarelli, C. %A Lefloch, B. %A Bachiller, R. %< avec comité de lecture %@ 0004-6361 %J Astronomy and Astrophysics - A&A %I EDP Sciences %V 591 %8 2016 %D 2016 %Z 1605.08318 %Z 2016A&A...591L...2V %R 10.1051/0004-6361/201628427 %K astrochemistry %K line: identification %K molecular data %K radiative transfer %Z Sciences of the Universe [physics] %Z Sciences of the Universe [physics]/Astrophysics [astro-ph]Journal articles %X The L1544 prestellar core has been observed as part of the ASAI IRAM Large Program at 3 mm. These observations led to the detection of many complex molecules. In this Letter, we report the detection of two lines, at 85.5 GHz (40,4-30,3) and 106.9 GHz (50,5-40,4), respectively, of the protonated carbon dioxide ion, HOCO+. We also report the tentative detection of the line at 100.4 GHz (50,5-40,4) of DOCO+. The non-LTE analysis of the detected lines shows that the HOCO+ emission originates in the external layer where non-thermal desorption of other species has previously been observed. Its abundance is (5 ± 2) × 10-11. Modelling of the chemistry involved in the formation and destruction of HOCO+ provides a gaseous CO2 abundance of 2 × 10-7 (with respect to H2) with an upper limit of 2 × 10-6. %G English %2 https://insu.hal.science/insu-03670227/document %2 https://insu.hal.science/insu-03670227/file/aa28427-16.pdf %L insu-03670227 %U https://insu.hal.science/insu-03670227 %~ IRD %~ INSU %~ METEO %~ UNIV-SAVOIE %~ UNIV-TLSE3 %~ UGA %~ CNRS %~ INPG %~ IRSTEA %~ CNES %~ OSUG %~ OMP %~ OMP-IRAP %~ IPAG %~ AGREENIUM %~ INRAE %~ UGA-COMUE %~ USMB-COMUE %~ UNIV-UT3 %~ UT3-INP %~ UT3-TOULOUSEINP %~ TEST3-HALCNRS