टाटा मूलभूत अनुसंधान संस्थान
Tata Institute of Fundamental Research

Homi Bhabha Road, Mumbai 400005, India

Home | Search | Sitemap | People Finder | Mail to Webmaster

Departments

The School of Natural Sciences at TIFR encompasses research in the areas of Biology, Chemistry and Physics. Below, you will find brief descriptions of the research directions pursued in each of these disciplines, as well as links to the Home Page of the relevant Department/Centre wherever this exists.

Department of Astronomy and Astrophysics

The Department of Astronomy and Astrophysics at Mumbai, which began in the late sixties as a section for High Altitude Studies, started with experiments in observing heavy cosmic primaries, cosmic electron spectra and hard X-rays from various sources and the cosmic X-ray background. It was mostly based on balloon borne payloads for which a facility was set up in Hyderabad to make and launch stratospheric balloons. This led to balloon based observations in X-ray and infrared astronomy. Soft X-ray astronomy payloads were also launched in sounding rockets from TERLS, Thumba and Sriharikota to study the X-ray sources, hot interstellar medium and soft X-ray cosmic background. These programs were later extended to satellite based instruments in X-ray and gamma ray wavelengths, and the group was renamed as Space Physics section and around the same time the theoretical astrophysics section was added. The department acquired its present name around 1997.

The department members carry out observations over a wide range of wave lengths in the electro-magnetic spectrum, from radio, infrared and optical wavelengths to ultra-violet, X-ray and gamma rays. The work in the department covers a wide range of astronomical objects, from the Sun and other stars to compact stellar objects like the neutron stars and black-holes as well as the interstellar medium, stellar clusters, galaxies, clusters of galaxies and the universe as a whole. The work ranges from observations, data analysis and modelling to building of new detectors and telescopes.

The theorists study a variety of topics in astrophysics, like accretion disks around black-holes and neutron stars, gravitational collapse in general relativity, gravitational lensing, cosmology, quantum gravity, neutron stars, pulsars, supernovae as well as more typical stars like the Sun. The work on helioseismology has provided accurate knowledge of structure and dynamics of the Sun and its temporal variations over the solar cycle. This should be a valuable input to the work on star formation and initial mass function. Thus, new data from instruments like ALMA, could be used to map the star formation history of galaxies at high redshifts. This will be put in the context of constraints on star-formation history currently being obtained from deep X-ray surveys with CHANDRA, with the aid of theoretical understanding of the X-ray evolution of galaxies developed here. Theoretical studies of compact binaries is a major effort, with current interest in the formation and evolution of X-ray binaries in globular clusters. Along with the observational work on supernova and supernova remnants these activities could possibly shed light on massive star formation in early universe, formation of black-holes and re-ionisation of the intergalactic medium. The gravitational lensing work has led to the prediction of the Einstein ring and optically faint hot galaxy clusters at high redshift. Naturally, a firm understanding of the end point of stellar evolution for massive stars will have far reaching implications to some fundamental questions in general relativity, like, the cosmic censorship conjecture. Equally it has relevance to the mechanism of energetic phenomena like gamma ray bursts. This work also provides a framework to develop theory for the challenging problem in quantum gravity, where observational signatures will be valuable. The cosmologists are working on understanding dark energy and structure formation, which are among the important problems in cosmology.

Infrared and X-ray astronomy are core areas in the department for observational studies. The infrared astronomy group has distinguished itself with its expertise in diffraction limited angular resolution and built the world's largest aperture far Infrared telescope for mapping in photometric bands and spectroscopic line. Apart from far infrared observations from balloon based telescope the members have also done ground based observations in near infrared and optical wavelengths and are now developing instruments for space based observations. These observations have been used to study star formation in our galaxy and other spiral galaxies, as well as structure and energetics of galactic star forming regions through high angular resolution far infrared spectroscopic and photometric mapping. The combined strengths of high angular resolution, use of longer wavebands beyond the limit of even stressed photoconductors (~ 200 micron, using bolometers), and robust image de-convolution schemes have created a niche and ensured quality science. This has been demonstrated in numerous studies of galactic star forming regions, leading to a better understanding of physical conditions and processes in their interstellar medium.

The X-ray astronomers have conducted timing and spectral studies of black holes and neutron star binaries, cataclysmic variables, nuclei of active galaxies and quasars and X-ray spectroscopy of stellar coronae and energetic phenomena on the Sun, as well as study of hot interstellar medium and supernova remnants. The study of neutron stars provides a unique opportunity to study superdense (5-10 times the nuclear density) cold matter. X-ray astronomy has made rapid strides using X-ray telescopes in soft X-rays (< 10 keV), while the astrophysics of hard X-rays from cosmic objects has not seen similar advance. This is mainly because of high background and the low flux in high energies from cosmic sources. Instruments are being developed to meet these challenges. Hard X-ray imaging by multi-layer coating and development of new generation hard X-ray detectors are a few of the areas where substantial research is being carried out. Some novel concepts in hard X-ray imaging and spectroscopy like Fresnel Zone Plate imaging, near-room temperature solid state detector technology, CMOS detector for hard X-rays etc., are incorporated in the RT-2 experiment onboard the Coronas-Photon satellite (an Indo-Russian collaborative experiment for solar flare studies in hard X-rays and gamma-rays), scheduled to be launched in December 2008.

Members of the department are actively involved in designing and building instruments for the first Indian multi-wavelength astronomy satellite, ASTROSAT, which will probe, among other things, the physics of black holes, which are among the most exotic predictions of Einstein's general theory of relativity. The instruments being developed in the department include the Large Area Xenon Proportional Counter (LAXPC) for timing and spectral studies in X-rays, as well as a Soft X-ray Telescope (SXT) for imaging studies and a new generation of X-ray detector in the Cadmium-Zinc-Telluride coded mask Imager (CZTI). While some members are involved in the development of Ultra-violet Imaging Telescope (UVIT) on ASTROSAT in collaboration with other institutes in India and abroad. One of the principle aim of ASTROSAT is to perform simultaneous multi-wavelength monitoring of intensity variations in a broad range of cosmic sources.

The department also runs the National Balloon Facility at Hyderabad, which has become a major centre for scientific ballooning. Regular balloon flights are conducted to make observations in Infrared and X-ray wavelengths, which are not accessible from ground. The balloon facility has also exported balloons to various agencies worldwide.

List of Research Activities:

  1. Theoretical Astrophysics:
    • Solar Physics, Helioseismology
    • Spin Evolution of Neutron Stars, Accretion-powered Pulsars
    • Relativistic Astrophysics around Black Holes
    • Neutrino-induced Nucleosynthesis
    • Supernovae, Nuclear Astrophysics
    • Gravitational Lensing, Large scale structure and Cosmology
    • General Relativity, Quantum gravity, Gravitational collapse
  2. Infrared and Optical Astronomy:
    • Study of star formation in our Galaxy and other spiral galaxies
    • Structure and energetics of Galactic star forming regions
    • Radiative transfer in interstellar clouds
    • Infrared studies of circumstellar shells
    • Young stellar objects and AGB stars
    • Physics and Chemistry of Photon Dominated Regions
    • Study of the Galactic structure
  3. X-ray and Gamma ray Astronomy:
    • X-ray Spectroscopy of Stellar Coronae
    • Galactic Black Hole Candidates
    • Cataclysmic variables
    • Nuclei of Active Galaxies and Quasars
    • Study of Hot Interstellar Medium and Supernova Remnants
    • Binary X-ray Pulsars
    • Rotation Powered Pulsars and Magnetars
    • Neutron Stars in Accreting Binary Systems

More details about the department can be found in its home page .

Department of Biological Sciences

It is clear that the next few decades will see exciting new discoveries in the field of the biological sciences. Basic research in Biology has already made a huge impact on medicine, agriculture and the environmental sciences, and this is bound to increase in the years to come.

TIFR conducts research in modern biology at The Department of Biological Sciences, TIFR-Mumbai . Model organisms for research have been chosen keeping in mind the advantage that each system offers for the question being studied. Hence some biologists focus their attention on single celled organisms- bacteria, yeasts, unicellular plants and the malarial parasite. These studies provide information on the molecules and processes occurring within individual cells. Others researchers focus on more evolved organisms such as Drosophila , Mouse and Zebrafish as model systems to understand development and behaviour in more complex systems.

Biologists at TIFR are addressing a spectrum of questions ranging from the function of single genes/proteins to behaviour of complex organisms. Some broad areas of research are listed below.

List of Research Activities:

Further information is available at the Department homepage .

National Center for Biological Sciences (NCBS-Bangalore) is an independent research institute under TIFR.

Department of Chemical Sciences

The department offers challenging opportunities for research in modern areas of physical chemistry as well as inter-disciplinary research between physics, chemistry and biology. The research activities of the department at present are focused on understanding interactions between small molecules at the most fundamental level on one hand and investigating the structure, function and dynamics of macromolecules such as proteins, nucleic acids etc. on the other. These investigations are directed towards understanding biological function at molecular level and towards design and development of novel molecular materials with desired characteristics and properties.

The department has set up sophisticated facilities such as: National Facility for High field NMR consisting of 500 and 600 MHz NMR spectrometers; Steady-state and time-resolved pico and femto second fluorescence spectrometers, ESR, CD and stopped-flow spectrometer, MALDI-TOF etc. The department is continually upgrading its facilities to keep abreast of developments in research facilities. In addition, there are home-built sophisticated experimental facilities for carrying out supersonic jet spectroscopy, multi-photon microscopy, Fluorescence correlation spectroscopy (FCS), time-domain ESR, and T-jump spectrometer. The department also has well-equipped chemical and biological laboratories for synthetic and protein-engineering research.

The department has been continually initiating and developing new and emerging areas of research in chemical sciences in addition to strengthening the current activities. The members of the department collaborate extensively with other departments of the Institute and also with other organizations at the national and international level.

The spectrum of current research activities is given below.

Current Research Activities:

More details about the department can be found in its home page .

Department of Condensed Matter Physics and Materials Science

In our daily life we often encounter matter in the form of crystals, amorphous solids such as glass and liquids of various kinds. Their investigation is at the heart of Condensed matter Physics and Materials Science - the study of properties of matter in relation to external factors like temperature, pressure, magnetic fields and size. Matter can transform from one state to another under suitable conditions. For instance, at very low temperatures, matter may become "superfluid", which means that it can flow without any resistance to its motion, or it may be "superconducting", in which case it can carry current with absolutely no resistance.

Such properties of matter are exciting both because they offer a window to the fundamental laws of nature, and because they are useful in developing advanced technologies which can change the way we live. Scientists at the Institute have been successful in identifying a new class of superconductors called borocarbides, and have studied the nature of exotic magnetism and superconductivity. They have been able to shed light on the interactions that led to the different types of magnetism in metallic alloys and oxides. Novel optoelectronic devices based on semiconductors have been designed and laser techniques have been used to fabricate high quality superconducting thin films which can carry currents more than million amperes at low temperatures.

List of Research Activities:

More details about the department can be found in its home page .

Department of High Energy Physics

The Nature's most fundamental questions can be posed as: (a) What is matter? (b) Where does it come from? (c) How does it stick together into complicated objects like stars, planets and human beings? The goal of Particle Physics is simply to learn what matter is made up of at the deepest level and what fundamental interactions they experience. The objects of study are both elementary particle, the inner space and the Universe, the outer space.

Fundamental research at the highest energy with the smallest particles is possible by accelerating, crashing particles into each other and then recording what happens. Starting from experiments with cosmic rays and radioactivity, today's particle accelerators allow physicists to explore particle collisions in a more controlled fashion which recreate the conditions prevailing at the start of the universe. The quest for pure knowledge drives the technology forward and state-of-the-art techniques are essential in all sectors of HEP experiments which are unlike in any other branch of science, designed and operated by hundreds of scientists, the detectors often are as big as multi-storied buildings, running for several years which demand international collaboration in every sense. A good number of scientists in the department are mainly involved in various stages of front ranking experiments at various global centres: L3 and CMS at CERN, D0 at Fermilab and BELLE at KEK. They participate actively in designing and fabricating part of the detectors, collecting and analyzing data, developing overall software for the experiment and preparing for future experiments. Revealing the mystery of nature as it keeps unfolding into deeper level with the progress of our understanding is like the task of a detective.

Many exciting problems of High Energy Physics can be experimentally addressed without recourse to the large particle accelerators. The field of Non-Accelerator Particle Physics, which has had a rich history at TIFR, continues to be vigorously pursued through a variety of experimental programmes today. Cosmic Rays and Gamma Rays of extremely high energies (~ 1021 eV) constantly bathe the Earth, and provide us our only direct knowledge of particle interactions at these energies. These are studies at dedicated experimental facilities like GRAPES experiment at Udhagamandalam (Ooty), PACT experiment at Pachmarhi and high altitude HAGAR experiment at Hanle (Ladakh). Paradoxically, the study of low energy phenomena in delicately designed experiments (such as in a search for weak fundamental forces, or for probing the discrete symmetries of nature) also yields profound insights into High Energy Physics, and such work too is pursued at the Institute.

List of Research Activities

More details about the department can be found in its home page .

Department of Nuclear and Atomic Physics

Most of the matter in the universe exists only in the gaseous state, and often in an ionized form. Laboratory studies with many ionized species are being pursued in the Institute to understand the processes which occur in astrophysical and plasma environments.

Lasers and heavy ion beams from an accelerator are being increasingly used in this connection. At the heart of the atom sits the nucleus. The study of nuclear structure and nuclear reactions was earlier carried out with light particle beams. A heavy-ion accelerator known as the ``Pelletron'', installed here a decade ago, has extended the studies in nuclear physics. Heavy ion beams from this accelerator, colliding with nuclei in the target, result in fusion reactions in which exotic nuclei are created. This provides the setting to investigate nuclear matter at high excitation energies and angular momenta. A superconducting linear accelerator is being developed to boost the energies of particles available from the Pelletron.

Research in atomic, molecular and optical sciences has been given a major thrust in the last few years. The interaction of high energy (MeV), highly charged ion beams are used as a probe to investigate the mechanisms of atomic collisions under weak and strong perturbations in collisions with molecules, clusters and solids: collective plasma excitations, nano-scale electron-interference, two-center post collision effect and higher order processes. Investigations using newly installed highly charged ions from ECR source can be used to probe interdisciplinary fields at low energies (keV). In addition, collision techniques that have been pursued for a long time are now being aided by lasers. The latter are used to prepare the collision targets in specific energy states to study state-selective collisions. Ultrashort (femtosecond) lasers producing very high peak powers are being used to explosively ionize matter and study its behaviour at these extreme, "implosive" excitation conditions. Nonlinear optical properties of emerging and novel materials are being studied to understand how material structure influences its optical response. The general aim of this entire work is to understand structural changes in atoms and molecules in a dynamic fashion under gentle as well as extreme external influences.

On a different note, several mesoscopic phenomena that have been the center of a physicist's curiosity are now attacked using optical waves. For example, the transition of a conductor to an insulator via Anderson localization is studied using light in a disordered medium. Nanostructured materials are used to create optical media with configurational disorder or order. The latter case leads to photonic crystals, which are believed to be templates for all-optical communication devices.

List of Research Activities:

  1. Nuclear Physics and Condensed matter studies using nuclear techniques:
    • Nuclear structure and spectroscopy of high spin states in exotic nuclei
    • Giant dipole resonance in nuclei
    • Transfer reactions and incomplete fusion
    • Nuclear physics near the Coulomb barrier
    • In-beam hyperfine interaction studies in novel materials.
  2. Atomic, Molecular and Optical Sciences:
    • Ion-atom and ion-molecule collisions
    • Interaction of electrons, ions and neutrals with laser excited molecules
    • Interaction of matter in intense laser fields
    • Non-linear optics
    • Biophysics
    • Quantum Computing and Optical Communications
    • Coherent control
    • Physics of clusters
    • Accelerator based atomic physics.

More details about the department can be found in its home page .

Department of Theoretical Physics

It is essential in any research institute to have a group doing theoretical work, for the purpose of analyzing existing experiments, suggesting what experimenters should look for in the future, and predicting new results. Theoreticians also work to formulate a consistent mathematical picture of the fundamental laws of nature.

At the Institute some theoreticians study experimental results from the major particle accelerators and investigate theoretical models of the elementary particles and their interactions. Scientists have also been working on the properties of nucleons and the quarks within them, and the confining interactions among quarks.

New theories like "String Theory" which aim to unify all the basic interactions including the gravitational force, and exotic phenomena like the quantum behaviour of black holes, are being investigated. Even the foundations of quantum mechanics, now accepted as one of the centrepieces of physics, are under scrutiny to learn whether they can be modified to produce an improved theory.

Theorists working in condensed matter and statistical physics are investigating novel collective behaviour in a variety of systems with very many interacting constituents, examples of which range all the way from sandpiles to superconductors. Many important results have been obtained at TIFR in all of the above areas.

List of Research Activities:

More details about the department can be found in its home page .

Copyright : TIFR ; Author : Chaudhari Nitin ; Created on 2005-01-01 ; Last modified on 2010-04-15.