A large number of the species observed in the gas phase of the interstellar medium (ISM) are thought to be formed on or in the ices coating interstellar dust grains and subsequently released through either photo- or thermal desorption processes. Infrared (IR) spectroscopy and mass spectrometry (MS) are the dominant techniques for studying laboratory analogs of these ices and their desorption properties. However, high-resolution submm/microwave spectroscopy is the method-of-choice for the remote sensing of trace complex species in the gas phase of the ISM. Coupling of these two techniques in the same experimental system could not only be a means to understand the desorption process but would also provide a means to detect trace species released from ices - with a sensitivity and an ability to uniquely identify such species that are unparalleled by IR or MS methods. Moreover, submm spectra of species released in laboratory analogs would provide a more straightforward comparison to observed gas-phase interstellar spectra. In order to fully understand the chemistry that leads from molecules within an ice to those in the gases of the ISM, we have built an experimental system to study the chemistry above the surfaces of laboratory ice samples during heating and/or photoprocessing. The experimental setup employs submm spectroscopy, the same technique used for remote observations of complex organics towards the ISM, in order to detect trace species that are sublimated by the interstellar ice analogs. We will describe the details of this experiment and present some preliminary results acquired for simple ice systems involving H<sub>2</sub>O, CH<sub>3</sub>OH, and/or CO. Implications of this new technique, such as the study of the interface between interstellar gas and ice, will be discussed.

Submillimeter spectroscopy of sublimated interstellar ice analogs: A new technique for laboratory astrochemistry

256th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.