The molecular species hydrogen peroxide, HOOH, is likely to be a key ingredient in the oxygen and water chemistry in the interstellar medium. Our aim with this investigation is to determine how abundant HOOH is in the cloud core {\rho} Oph A. By observing several transitions of HOOH in the (sub)millimeter regime we seek to identify the molecule and also to determine the excitation conditions through a multilevel excitation analysis. We have detected three spectral lines toward the SM1 position of {\rho} Oph A at velocity-corrected frequencies that coincide very closely with those measured from laboratory spectroscopy of HOOH. A fourth line was detected at the 4{\sigma} level. We also found through mapping observations that the HOOH emission extends (about 0.05 pc) over the densest part of the {\rho} Oph A cloud core. We derive an abundance of HOOH relative to that of H_2 in the SM1 core of about 1\times10^(-10). To our knowledge, this is the first reported detection of HOOH in the interstellar medium.
@article{arxiv.1105.5799,
title = {Detection of interstellar hydrogen peroxide},
author = {P. Bergman and B. Parise and R. Liseau and B. Larsson and H. Olofsson and K. M. Menten and R. Güsten},
journal= {arXiv preprint arXiv:1105.5799},
year = {2011}
}
Comments
5 pages, 4 figures, accepted for publication in Astronomy & Astrophysics, new version corrects a typo in Table 1 (and consequently in Fig 4)