June-2018 Seminar

Title : TBA

Date : 28-06-2018
Time : 16:00:00
Speaker : Mr. Bhavesh Chauhan
Senior Research Fellow
Area : Theoretical Physics
Venue : Room No. 469

Abstract

TBA

Title : Topic- Color Superconductivity for Magnetized three flavour quark matter

Date : 21-06-2018
Time : 16:00:00
Speaker : Mr. Aman Abhishek
Post Doctorate Fellow
Area : Theoretical Physics
Venue : Room No. 469

Abstract

At high enough density the quark matter becomes deconfined and the fermi surface is unstable to cooper pair formation. Such a phenomenon is known as Color superconductivity. There are various phases of color superconductivity which can be modified in the presence of external background magnetic field. Such a phase may be present in the interior of neutron stars. In the present work we study the color superconductivity in three flavor quark matter in the presence of magnetic field within the framework of Nambu-Jona Lasinio model. I will also discuss the effect of charge neutrality on color superconductivity.

Title : Decoding cosmic fingerprints: constraining the generation and evolution of primordial fluctuations

Date : 14-06-2018
Time : 16:00:00
Speaker : Dhiraj kumar hazra
Area : Theoretical Physics
Venue : Room No. 469

Abstract

It is the origin and evolution of quantum fluctuations that eventually lead to the formation of the Large Scale Structure (LSS) in the Universe. The primordial perturbations emerge through the radiation and thereafter the matter dominated epochs and finally to today's dark energy dominated epoch, leaving their distinct fingerprints in the photons that we observe. Photons from the Cosmic Microwave Background (CMB), quasars, galaxies and clusters, supernovae, stars etc. can be analyzed to trace these fingerprints. In this talk, I will mainly discuss decoding three different fingerprints originating from three different epochs in the timeline of the Universe, namely, CMB from the last scattering surface, Lyman-alpha observations from reionization and post-reionization eras and the galaxies observed in the LSS. Since signals from different cosmological processes are convolved in our observations, effective joint analyses are required to converge towards the most probable model of the Universe. I will outline the standard model and few extensions beyond that agree remarkably with the present data. I will also discuss model independent reconstruction methods that can lead to possible scenarios of the Universe directly from the data. I will conclude with forecasts from the upcoming and proposed cosmological missions.

Date : 12-06-2018
Time : 16:00:00
Speaker : Dr. Ikshu Gautam
Post Docterol Fellow
Area : Geosciences Division
Venue : Ground Floor Lecture Hall

Abstract

The Hadean Eon, representing the first five hundred million years of Earth’s history, was one of the most eventful periods when the planet got differentiated to various chemical layers based on density. One of these major events was the segregation of core and mantle from bulk Earth. Direct evidence for subsequent differentiation of the earliest differentiation of mantle is difficult to find, as the preserved Hadean rock record is scanty. However, information about these events can be obtained with the help of extinct radioactivity, in particular from 146Sm-142Nd systematics (Half-life of 103 Ma). Surprisingly, such evidence is not only restricted to the oldest rocks but also found in some infant rocks. In this talk I will discuss recent findings which provide a new perspective on the preservation of such evidence through geologic time. Some similar efforts by us in this direction will also be discussed.

Title : Water-rock interaction on Mars: In-situ and microscopic observations

Date : 08-06-2018
Time : 16:00:00
Speaker : Dr. Amit Basu Sarbadhikari
Area : Planetary Sciences Division
Venue : Room no 113, Thaltej Campus

Date : 05-06-2018
Time : 16:00:00
Speaker : Dr. Rouf Ahmad Shah
Post Doctoral Fellow
Area : Geosciences Division
Venue : Ground Floor Lecture Hall

Abstract

Karst aquifers contribute substantially to freshwater and thermal water supplies in many region of the world. Kashmir Valley, one of the largest karst region on the Indian Subcontinent and the Himalaya, provides significant karst geomorphic imprint due to wide distribution of carbonate rocks. Karstified carbonate rocks has a high hydraulic conductivity ~1000m d-1, thereby, represents a major hydrogeological unit and a regionally important groundwater reservoir. Dissolution of carbonate rocks, (development of exokarstic and endokarstic features), abundant water resources in the form of large cold and warm springs, and subsequent development of floating gardens designed at spring outlets, has led to label the karst areas in the region as State Geoparks, which features the region a popular holiday destination, a backbone to regional economy. Past phreatic morphology and present relict nature suggest that the landscape evolution has changed the hydrologic conditions from phreatic to vadose, and thereby, modified the processes of speleogenesis and the characteristics of the caves. The uplift and erosion in Pilo-Plestocene is dynamic cause which governed the processes of karst development, likewise, climatic oscillations in the same period changed the solutional rates, and dominance of either chemical or mechanical. Although the spring flow is dominantly controlled by the melting of snow and/or glaciers, rain events produce sharp spikes in spring hydrographs, primarily responsible for the undulating/seasonal trend in the δ2H and δ18O of the karst springs. Furthermore, the study provides new insights in understanding the dominant factors affecting the isotopic composition of the precipitation, snowpack, glacier melt, streams and springs. δ18O/ or δ2H of precipitation, snowpacks, glacier melt and karst springs show wide variation both in space and time, and are strongly influenced by the basin relief and meteorology. Similar temporal trends of isotopic signals in streams and karst springs reflect the rapid flow transfer due to karstification of the carbonate aquifers. Tracer breakthrough curves (TBC), retrieved for different springs suggest short travel time (2 to 7 d) and rapid conduit flow, which has practical consequences like, deterioration of water quality and variation in magnitude of groundwater flux in the region.

Title : TBA

Date : 04-06-2018
Time : 14:30:00
Speaker : Mr. Arun Kumar Pandey
Post Doctorate Fellow
Area : Theoretical Physics
Venue : Room No. 469

Abstract

TBA

Title : Determination of Martian Atmospheric Heating Rates

Date : 01-06-2018
Time : 16:00:00
Speaker : Mr. Masoom Jethwa
Area : Planetary Sciences Division
Venue : Room no 113, Thaltej Campus