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Formic acid (HCOOH) has been extensively detected in space environments, including interstellar medium (gas and grains), comets and meteorites. Such environments are often subjected to the action of ionizing agents, which may cause changes in the molecular structure, thus leading to formation of new species. Formic acid is a possible precursor of pre-biotic species, such as Glycine (NH2CH2COOH). This work investigates experimentally the physicochemical effects resulting from interaction of heavy and energetic cosmic ray analogues (46MeV 58Ni11+) in H2O:HCOOH (1:1) ice, at 15 K, in ultrahigh vacuum regime, using Fourier transform infrared spectrometry in the mid-infrared region (4000-600 cm-1 or 2.5-12.5 microns). After the bombardment, the sample was slowly heated to room temperature. The results show the dissociation cross-section for the formic acid of 2.4x10^-13 cm2, and half-life due to galactic cosmic rays of 8x10^7 yr. The IR spectra show intense formation of CO and CO2, and small production of more complex species at high fluences.
Sulfur is an abundant element in the cosmos and it is thus an important contributor to astrochemistry in the interstellar medium and in the Solar System. Astronomical observations of the gas and of the solid phases in the dense interstellar/circumste
Enceladus, a small icy moon of Saturn, is one of the most remarkable bodies in the solar system. This moon is a geologically active object, and despite the lower temperatures on most of its surface, the geothermally heated south polar region presents
In this work, we studied the stability of the glycine molecule in the crystalline zwitterion form, known as {alpha}-glycine ($^{+}$NH$_{3}$CH$_{2}$COO$^{-}$) under action of heavy cosmic ray analogs. The experiments were conducted in a high vacuum ch
Deeply inside dense molecular clouds and protostellar disks, the interstellar ices are protected from stellar energetic UV photons. However, X-rays and energetic cosmic rays can penetrate inside these regions triggering chemical reactions, molecular
HCN is a molecule central to interstellar chemistry, since it is the simplest molecule containing a carbon-nitrogen bond and its solid state chemistry is rich. The aim of this work was to study the NH3 + HCN -> NH4+CN- thermal reaction in interstella