Between the stars (Lecture - 10) by G Srinivasan
Time: 10:00 AM Venue: Ramanujan Lecture Hall / Madhava Lecture Hall, ICTS Campus, Bangalore This summer course aims to give a broad perspective on gravity, astrophysics and cosmology and is suitable for advanced undergraduates and graduate students in physics and astronomy. Professor G Srinivasan is a specialist in Condensed matter Physics and Astrophysics and is an excellent teacher. After acquiring his PhD from the University of Chicago in 1970, he had a distinguished career as a scientist and teacher at the IBM Research Laboratory, Chalmers University of Technology, University of Cambridge, and Raman Research Institute. He has done pioneering work in condensed matter physics and astrophysics, and is the author of the best selling popular science books “What Are The Stars?” and “Can Stars Find Peace?”. Topics: L1 : Einstein's Theory of Relativity L 2 : Principles of Radiative Transfer L 3 : What are the stars? L 4 : The solar neutrino puzzle. L 5 : White Dwarfs as Quantum stars. L 6 : Neutron Stars. L 7 : Pulsars L 8 : Black Holes I L 9 : Black Holes II L 10 : Between the stars. L 11 : Supernovae L 12 : Contemporary Cosmology I L 13 : Contemporary Cosmology II URL: https://www.icts.res.in/courses/summe... Table of Contents (powered by https://videoken.com) 0:00:00 A journey through the Universe 0:00:08 Between the stars (Lecture-10) 0:02:08 The Interstellar Medium 0:05:24 As we journey through the interstellar space, we will encounter spectacular gaseous nebulae and remnants of supernovae. 0:05:52 Pillars of dust in the Eagle Nebula 0:06:23 Cassiopeia A, the expanding supernova remnant 0:06:34 X-ray image of the remnant of TYCHO's supernova 1572 0:07:03 In addition to these discrete objects, there is also widespread atomic hydrogen. 0:26:09 Discovery of interstellar hydrogen 0:32:09 The "Doppler shifted frequencies" will be different for the three clouds 0:36:44 Modelling the distribution of neutral hydrogen in the Galaxy 0:37:09 Random motion of clouds superimposed on their systematic motion around the center of the Galaxy. 0:37:47 The distribution of the neutral hydrogen gas in the Milky Way. 0:40:06 Neutral hydrogen gas is heavily concentrated on the plane of the Galaxy. The thickness of the atomic gas is approximate 700 light years. 0:42:35 Raisin pudding model of the Interstellar Medium 0:51:22 Interstellar Medium - Molecular Gas 0:51:31 Molecular Spectra 0:53:17 Rotational spectrum: A rotating will radiate only if it has a permanent electric dipole moment. 0:56:51 Spectral region of rotational transitions 0:58:54 Vibrational levels 1:00:04 In quantum mechanics, energy levels of simple harmonic oscillation are quantized, and equally spaced. 1:02:46 Molecules in interstellar space 1:12:59 Giant Molecular Clouds 1:18:31 All or nothing 1:20:17 How are giant molecular clouds formed? 1:22:10 A molecular cloud. Because they contain a lot of dust particles, they are opaque light. 1:22:46 A small section of a molecular cloud 1:22:54 M 51 - Whirlpool Galaxy. Right is the visible image. The Dark lanes trace the distribution of Dust 1:24:13 Distribution of molecular clouds is shown in BLUE 1:25:08 Molecular clouds are birth places of stars 1:30:01 A star cluster in the Rosette Nebula. The wavelength of the recombination radiation will tell us about the composition of the gas 1:34:19 Visible radiation is mostly from massive stars. Remember luminosity is proportional to the cube of the mass! 1:35:25 Far infrared image of the Andromeda galaxy. The IR traces the dust as well as star formation. 1:40:54 Q&A
