Title : The Role of Layered Minerals in the Origin of Life Insights from Planetary Analogue Terrestrial Geomaterials​

Abstract

How did life begin? Researchers believe that certain minerals, especially clays, played a big role in this process. These minerals can hold onto organic molecules, help chemical reactions happen, and create safe spaces for early life to form. Since they exist on Earth and other planets, they also help us search for signs of life beyond our planet. These layered minerals, abundant in terrestrial and extraterrestrial environments, serve as key indicators of fluid-rock interactions and potential biosignature preservation. This talk will explore how clays can serve as one of the potential planetary analogue terrestrial geomaterials that can enhance our understanding of life’s emergence. By employing comprehensive biogeochemical fingerprinting, this research will characterize clay minerals in terrestrial settings, assessing their capacity to preserve biosignatures. By studying layered minerals on Earth and extending these findings to available extraterrestrial samples, we can unveil the largely unexplored role of clay minerals in the origin of life, which is essential for planning future astrobiological missions.

Title : A Monte Carlo Approach to Temperature and Spectral Energy Distribution in Protoplanetary Disks

Abstract

A protoplanetary disk is a rotating circumstellar disk of dense gas and dust surrounding a young star. Understanding the structure and composition of these disks is essential for understanding the processes involved in planet formation. Over the years, various models have been developed to describe the chemical and hydrodynamic processes occurring within these disks. Here, we introduce a Monte Carlo Radiative Transfer (MCRT) model to characterize the temperature distribution and spectral energy throughout the disk and its surrounding envelope. MCRT method provides an efficient means of achieving radiative equilibrium without iteration in systems with temperature-independent opacity sources. Additionally, the computational time required for this method is comparable to that of pure scattering models. The MCRT approach tracks individual photon packets, allowing for precise identification of energy absorption sites and subsequent adjustments to local cell temperatures. To enforce radiative equilibrium, each absorbed packet is instantly re-emitted, with its frequency selected to correct the cell’s thermal spectrum. These re-emitted packets can undergo scattering, absorption, and re-emission processes until they escape, enabling the system’s temperature and spectral energy distribution (SED) to reach equilibrium. We present the initial results of the simulations for both spherical symmetry models and 2D axisymmetric density structures, comparing the findings with standard benchmark tests.

Title : FIELD-ANGLE OPTIMIZED DESIGN FOR WIDE-FIELD IMAGING X-RAY TELESCOPES

Abstract

Wide field of view (FOV) imaging X-ray telescopes play a crucial role in addressing some of the most challenging and unresolved questions in modern astrophysics. For example, they are crucial for probing the early formation of supermassive black holes (SMBH), rigorously testing the hypothesis that nanoflares are the primary mechanism sustaining coronal temperatures above million Kelvin, and detecting the electromagnetic counterparts of gravitational wave events. However, existing optical designs for X-ray telescopes, such as the Wolter type-1 (W1) and Wolter-Schwarzschild (WS) configurations, offer high angular resolution only along the optical axis and are therefore limited to narrow FOVs (a few arcminutes), while the scientific cases mentioned above require high angular resolution across a much wider FOV (up to 60 arcminutes). In this talk, I will introduce a new optical design, the field-angle optimized (FO) design, specifically developed for wide FOV X-ray imaging telescopes. I will discuss the methodology behind this design, compare its performance with existing optical designs, and explore its feasibility for implementation in wide FOV solar X-ray telescopes.

Title : Time domain photometric study of peculiar Blazars

Abstract

Blazars often exhibit random, aperiodic, and stochastic behaviours in their flux across all observational electromagnetic (EM) bands over a wide range of timescales. However, the underlying causes are not yet fully understood regarding which flux variations on the intra-day/day timescales are most poorly comprehended. These variations are primarily related to accretion or jet physics, as jets are powered by accretion. In the talk, I will elucidate my findings that include the quasi-periodic oscillatory signatures and flare episodes detected in three individual Blazar candidates observed with Transiting Exoplanet Survey Satellite (TESS).

Title : Habitat Selection by Early Humans in the Indian Subcontinent

Abstract

The dispersal of our species out of Africa is believed to have occurred in multiple phases from the middle to late Pleistocene. Earliest fossil evidences for this migration of Homo sapiens is documented around 200-100 kya. These dispersals are influenced by the climate shifts, which shaped their habitats during migration. According to the Southern Dispersal Hypothesis, the dispersal of Homo sapiens from Africa into South Asia (130–75 kya) coincided with periods of favorable monsoon-driven green corridors, which influenced migration pathways and habitat selection. In this seminar, we will explore hominin habitat selection patterns by reconstructing woody cover along these dispersal routes using pedogenic carbonates as a vegetation proxy, providing insights into the environments they might have encountered and adapted.