Understanding the physical conditions of dark molecular clouds and star forming regions is an inverse problem subject to complicated chemistry that varies non-linearly with time and the physical environment. In this paper we apply a Bayesian approach based on a Markov Chain Monte Carlo (MCMC) method for solving the non-linear inverse problems encountered in astrochemical modelling. We use observations for ice and gas species in dark molecular clouds and a time dependent, gas grain chemical model to infer the values of the physical and chemical parameters that characterize quiescent regions of molecular clouds. We show evidence that in high dimensional problems, MCMC algorithms provide a more efficient and complete solution than more classical strategies. The results of our MCMC method enable us to derive statistical estimates and uncertainties for the physical parameters of interest as a result of the Bayesian treatment.
Mapping of interstellar ices with JWST in protostellar envelopes: Spatial variations of $^{13}$CO$_2$, $^{12}$CO$_2$, CO, OCN$^-$ and H$_2$O ice
Leiden University（莱顿大学）；Max-Planck-Institut für Extraterrestrische Physik（马克斯·普朗克地外物理研究所）；University of Hawai’i at Manoa（夏威夷大学马诺阿分校）；University of Cambridge（剑桥大学）；Center for Astrophysics, Harvard & Smithsonian（哈佛与史密森尼天体物理中心）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；INAF-Osservatorio Astronomico di Capodimonte（意大利国家天体物理研究所卡波迪蒙特天文台）；The University of Toledo（托莱多大学）
SPHEREx Wide-Field Infrared Spectral Mapping of Interstellar Ices and Polycyclic Aromatic Hydrocarbons
Department of Physics and Astronomy, Seoul National University（首尔大学物理与天文系）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；IPAC, California Institute of Technology（加州理工学院红外科学应用中心）；Korea Astronomy and Space Science Institute (KASI)（韩国天文学与空间科学研究院）
The hunt for formamide in interstellar ices: A toolkit of laboratory infrared spectra in astronomically relevant ice mixtures and comparisons to ISO, Spitzer, and JWST observations
Korea Astronomy and Space Science Institute (KASI)（韩国天文与空间科学研究所）；Johns Hopkins University（约翰斯·霍普金斯大学）；Johns Hopkins University, Applied Physics Laboratory（约翰斯·霍普金斯大学应用物理实验室）；Infrared Processing Analysis Center, California Institute of Technology（加州理工学院红外处理与分析中心）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；Seoul National University（首尔大学）
An Ice Age JWST inventory of dense molecular cloud ices
冰质颗粒地幔是挥发性元素的主要储存库，这些挥发性元素将黑暗星际云中的化学过程与行星的形成及其大气成分联系起来。最初的冰成分是在恒星形成之前，在分子云的寒冷、密集部分形成的。凭借JWST的灵敏度，现在可以对冰演化的这一关键阶段进行详细研究。在这里，我们展示了早期发布的科学计划“冰河时代”的第一个结果，揭示了这些致密云冰的丰富成分。弱冰，包括，$^{13}$ CO $_2$，OCN $^-$，$^{13}$ CO，OCS和COMs功能组，现在检测到沿两个星前视线。$^{12}$ CO $_2$冰剖面表明冰粒的适度增长。列密度的主要和次要的冰物种表明，冰之间的主要C，O，N，和S元素的散装预算的2%和19%。我们的研究结果表明，简单和复杂分子的形成可以在水冰丰富的环境中早期开始。
Functionalization of Benzene Ices by Atomic Oxygen
Harvard-Smithsonian Center for Astrophysics（哈佛-史密森天体物理中心）；Harvard University（哈佛大学）；University of Bern（伯尔尼大学）；The Hebrew University of Jerusalem（耶路撒冷希伯来大学）；UC Berkeley（加州大学伯克利分校）
