Introduction to Astrochemistry by Divita Gupta

Описание: This talk is part of the Alumni Talk Series organised by The Astronomy Club at IISER-Mohali.

Title of the talk:
Exploring the Universe Beyond Astrophysics: Understanding Astrochemistry in Diverse Environments and How Arrhenius was proved (Partially) Wrong

About the speaker:
Divita Gupta is a Ph.D. student with Prof. Ian Sims at the Institute of Physics in Rennes, France working on an ERC Project CRESUCHIRP, where they aim to examine the products of low-temperature chemical reactions important in cold astrochemical environments. Divita completed her BS-MS in Chemistry from the Indian Institute of Science Education and Research Mohali, India, and did her Master’s thesis on the interaction of ethylene glycol and water using Matrix Isolation FT-Infrared Spectroscopy under Prof. K S Viswanathan.

Abstract:
Astrochemistry, also known as molecular astrophysics, is "the study of the formation, destruction, and excitation of molecules in astronomical environments and their influence on the structure, dynamics, and evolution of astronomical objects" as stated by the pioneer of this field, Alexander Dalgarno in 2008. The speaker will introduce this relatively young field of molecular science and discuss the journey of molecules through the Cosmos, from diffuse interstellar clouds to planetary systems.

The speaker will also briefly explain her work using Laval nozzles which have been used in rocket engines for a long time to propel and accelerate the combustion gases at hypersonic velocities. This design has been tweaked and applied successfully to study low-temperature chemistry as the gases through this nozzle can be cooled down to as low a temperature as 10 K. For a long time, it was thought that the reactions follow the Arrhenius rate law even at low temperatures, implying that the reaction rates will be too slow to proceed in the cold interstellar space. However, in the past decades, it has been shown that the reactions at low temperatures no longer follow Arrhenius Law and remain fast or become even faster!
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