INFRA-ICE: An ultra-high vacuum experimental station for laboratory astrochemistry

Abstract

Laboratory astrochemistry aims at simulating in the laboratory some of the chemical and physical processes that operate in different regions of the Universe. Amongst the diverse astrochemical problems that can be addressed in the laboratory, the evolution of cosmic dust grains in the different regions of the interstellar medium (ISM) and its role in the formation of new chemical species through catalytic processes present significant interest. In particular, in the dark clouds of the ISM dust grains are coated by icy mantles and it is thought that the ice-dust interaction plays a crucial role in the development of the chemical complexity observed in space. Here, we present a new ultra-high vacuum experimental station devoted to simulate the complex conditions of the coldest regions of the ISM. The INFRA-ICE machine can be operated as a standing alone setup or incorporated in a larger experimental station called Stardust, which is dedicated to simulate the formation of cosmic dust in evolved stars. As such, INFRA-ICE expands the capabilities of Stardust allowing the simulation of the complete journey of cosmic dust in space, from its formation in asymptotic giant branch stars (AGBs) to its processing and interaction with icy mantles in molecular clouds. To demonstrate some of the capabilities of INFRA-ICE, we present selected results on the UV photochemistry of undecane (C 11 H 24) at 14 K. Aliphatics are part of the carbonaceous cosmic dust and, recently, aliphatics and short n-alkanes have been detected in-situ in the comet 67P/Churyumov-Gerasimenko.

Photocleavage of Aliphatic C–C Bonds in the Interstellar Medium

“…All the experiments have been carried out in the INFRA-ICE module (Santoro et al 2020b) of the Stardust machine (Santoro et al 2020a;Martínez et al 2020;Accolla et al 2021;Sobrado et al 2023) in ultrahigh vacuum (UHV) conditions (base pressure at room temperature: 3 × 10 −10 mbar).…”

“…At the selected working conditions, the photon flux integrated over the whole spectral range is 6.2 × 10 14 ph s −1 cm −2 (Santoro et al 2020b). Total UV fluences of ca.…”

60 Karbonlu Fullerenlerin Astrokimyasal İncelemesi

“…Fulleren gözlemlerinin elde edildiği yoğunlaşma sıcaklığı koşullarının yetersizliği, bu konularda çalışan bilim insanlarını fullerenin kozmik ortamdaki sentez mekanizmasını anlamak için çeşitli senaryolar üretmeye yönlendirmektedir. Evrimleşmiş yıldız ortamdaki gaz fazı kimyasını taklit etmek için laboratuvarda özel Stardust (yıldız tozu) makinesini kullanarak deneyler yapılmıştır (Santoro ve diğ. 2020).…”