centre for astroparticle physics and space sciences – a national facility at bose institute
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Centre for Astroparticle Physics and Space Sciences – A National Facility at Bose Institute ( A project under IRHPA Scheme ) Sibaji Raha Bose Institute Kolkata. Acharya J.C. Bose (1858 – 1937). - PowerPoint PPT PresentationTRANSCRIPT
Centre for Astroparticle Physics and Space Sciences –
A National Facility at Bose Institute(A project under IRHPA Scheme)
Sibaji RahaBose Institute
Kolkata
Acharya J.C. Bose (1858 – 1937)Acharya J.C. Bose (1858 – 1937)
““India is drawn into the vortex of India is drawn into the vortex of international competition. She has to international competition. She has to
become efficient in every way – become efficient in every way – through spread of education, through spread of education,
through performance of civic duties and through performance of civic duties and responsibilities, through activities both responsibilities, through activities both industrial and commercial. Neglect of industrial and commercial. Neglect of these essentials of national duty will these essentials of national duty will
imperil her very existence.”imperil her very existence.” – Acharya J.C.Bose– Acharya J.C.Bose
Origin
1. In-house expertise : Need for consolidation
2. Darjeeling Campus : Location & Opportunities (a) Cosmic Ray (b) Atmospheric Chemistry (c) Radiometric studies
Four major programmes
1. Cosmic ray studies at high altitude
2. Changing airspace environment in Eastern Himalayas
3. Children’s science resource centre
4. Manpower development – training programmes
Cosmic Ray studies
Quark Symbol Spin Charge Baryon Number
Mass (GeV)
Up u 1/2 2/3 1/3 0.006
Down d 1/2 -1/3 1/3 0.010
Strange s 1/2 -1/3 1/3 0.150
Charm c 1/2 2/3 1/3 1.500
Bottom b 1/2 -1/3 1/3 5.100
Top t 1/2 2/3 1/3 175.0
Electrons – electric cherge - EM force – Photon
Quarks - Colour Charge - Strong force – Gluon
Quark – three colours - Red , Blue , Green
Gluons – eight - red + anti-blue and other combinations
Mesons – quark+antiquark – colour+anticolour – WHITE
Baryons – three quarks – red+blue+green - WHITE
H- matter P.T. Q – matterSQM Ground state of matterFirst idea : Bodmer (1971)Resurrected : Witten (1984)
Stable SQM : Conflict with experience ????
2-flavour energy > 3-flavourLowering due to extra Fermi well
Stable QM 3-flavour matterStable SQM significant amount s quarks
For nuclei high order of weak interaction to convert u & d to s
SQM & Strangelet Search : SQM :
1. Early universe quark-hadron phase transition Quark nugget MACHO 2. Compact stars (Core of Neutron Stars or Quark Stars)
Strangelets :
1. Heavy Ion Collision Short time Much smaller size A ~ 10-20 Stability Problem at high temperature 2. Cosmic Ray events : Collision of Strange stars or other strange objects Shower
Detection of strangelets
Propagation mechanism of strangelets
How far can it travel through atmosphere
How does it interact with atmosphere ?
Important observations
Stability of strange matter
Small positive charge massive s quark Z/A 1
Remarks :
Detection of strangelets : Passive detectors
Active detectors : Air shower studies in collaboration
Study ofChanging airspace environment
in Eastern Himalayas
Indo-Gangetic plane :
Agricultural as well as Industrial activity
Source of atmospheric pollutants
Vulnerable place from changing environment
Himalaya is subject to
(a) emissions from IGP regions
(b) pollutants transported from long distances
Himalaya : Unique place to monitor airspace
environment
Eastern Himalaya : wet with rich forest cover and lesser population
Western Himalaya : dry, scanty forest cover and high population
Monitoring stations :
Mostly in western Himalaya
North Bengal University, Siliguri
Darjeeling2500 meters
Kathmandu ICIMOD-UCSD Station
Sandakphu4200 meters
Pyramid Station
5034 meters
Eastern Himalaya Monitoring stations
Eastern Himalayas
Radio Environment
Chemical, Physical, and Radio Mapping of the region
Air Pollutant Dispersal 3-D Chemical Modeling
23.8 GHz (Water Vapour)31.4 GHz (Liquid Water)Distrometers (DSD)
Monitoring of trans-boundary pollutants
Physical Environment
3-D Trajectories
Met Data
Chemical Environment
H2O: mm wavesO3, CO, NOx, SO2: Trace
SpeciesAerosols: Scattering/
Absorbing
Emission Inventories
Workshops and summer schools on various
aspects of the :
cosmic ray physics
Instrumentation
Environmental science
Weather modeling studies
Numerical simulation
with hands-on training
Aimed at : Masters level and beginning doctoral
students
Active detectors : Air shower studies
• “Cosmic Rays” = subatomic particles
• Cosmic Rays= unknown origin ( Some clue – Image of supernova debris-Nature’04)
• Composed of various types of particle:
Primary Cosmic Rays
• Hydrogen nuclei (87%)
• Helium nuclei (12%) – “alpha particle”
• Nuclei from heavier elements
• High speed electrons – “beta particles”
Secondary Cosmic Rays
• Particles slam into gas atoms in upper atmosphere
• Fragments shower down and/or disintegrate:
• pions muons + neutrinos pion electron + positron + gamma rays
• Muon and neurtrinos make it to the surface of the earth
What are Cosmic Rays??
Future Plan
Solar Terrestrial weather and cosmic rays
Climate and Sun relationship
* First suggested by William Herschel 1801 : variation in solar irradiance ► climate change on earth variation of British wheat prices with sunspot numbers (sunspot ► a region on the sun’s surface, marked by lower
temperature )
* Little ice age : 1645 – 1715 Maunder Sunspot minimum
* Correlation between solar cycle variations and tropical sea-surface temperature
* Direct Link ► 1979-1990 cycle irradiance variation ~ 0.1% too small for direct effect
● Indirect Link Likely
● Solar radiation input in the lower atmosphere and cloudiness
Effect of Cloud :
a) cooling by reflecting solar radiation
b) warm the climate by trapping radiation
emitted from earth’s surface
● Cosmic ray particle : carriers of variability to the lower atmosphere
● Variation of cosmic ray on solar phenomena
An Example : Observation during solar eclipse of October 24, 1995
● Total solar eclipse :
period of totality 1 min 7sec.
● variation of γ rays in the
range 0.3 – 3 MeV
● Cosmic ray component :
Figure
Results
● Other effects
1. Cosmic ray intensity sunspot cycle 11 year cycle 2. Forbush Decrease : sudden decrease in cosmic ray in
intensity followed by gradual recovery during several days – weeks
Interplanetary shocks passing through earth’s orbit produce an effective barrier
shock occurs following solar coronal mass ejection
Mass ejection may occur in the absence of solar flare
Cosmic ray – climate
Cosmic ray – sunspot cycle – global cloud cover
11 year cycle
Cosmic ray – climate contd. ….Absolute % variation of global cloud cover observed by
Satellites and relative % variation of cosmic ray flux
Cosmic ray – climate contd. ….
Observation of 30% fall in rainfall on the initial day of the Forbush decrease
3. Forbush decrease – decrease of cloudiness
time scale days
Convection (also called "free convection" or "buoyant lifting"):
Topographic (also called "orographic lifting" or "forced lifting"):
Frontal lifting:
Blue: Cold air Red: Hot air
Blue: Cold air ; Red: Hot air
A cloud is composed of millions of little droplets of water (or ice crytals when temperature is very low) suspended in the air.
Hence a cloud can form when water vapor becomes liquid, i.e. when the humid air is cooled and condenses on tiny particles.
Cosmic Ray – Cloud formation
1. Enhanced aerosol nucleation and growth into cloud condensation nuclei
Cosmic Ray-Cloud Contd. ….
2. Enhanced CCN activation by charge attachment
▪ Aerosol activation rapid growth of an aerosol into large droplet
▪ Aerosol charging by cosmic ionization
Decrease the supersaturation Increase in droplet number
Cloud microphysics
Cosmic Ray-Cloud Contd. ….
3. Ions and radicals may promote the formation of
condensable vapours or enhance the condensation of vapours already present.
Cosmic Ray-Cloud Contd. ….
4. Creation of ice nuclei
Cosmic Ray-Cloud Contd. ….
5. Effect of cosmic ray on stratospheric clouds
and ozone depletion
(Previous processes occur in the troposphere)
Cosmic Ray – Cloud connection
Experiments and observations Cloud cover observation : satellite and ground based observations
Cosmic ray flux measurement
CERN : link between cosmic ray and cloud CERN Proton synchrotron
Adjustable cosmic ray source
CLOUD Project
Based on cloud chamber that is designed to duplicate the conditions
prevailing in the atmosphere.
GRAPES III Experiment
(Gamma Ray Astronomy at PeV(1015eV) Energies III)Ooty, Tamil Nadu
288 scintillation detector – to detect ray component of cosmic ray
3700 Proportional counters – to detect muon component
Large area muon detector – can be used for observation
on muons
produced by lower energy protons
affected by solar phenomena e.g. solar flares & coronal mass ejection
Useful for space weather forecasting
Our Goal
To understand the physics of
Solar activity (SF & CME)
Cosmic ray flux (FD)
Cloud formation
COMMITTEE FOR DAE-DST VISION FOR DRAWING UP A ROADMAP FOR HIGH ENERGY AND NUCLEAR PHYSICS
RESEARCH.
3 major areas : Particle Physics, Nuclear Physics &Astroparticle Physics.
Major recommendations:In all three fields, particle physics, nuclear physics and astro-particle
physics, • Indian groups are continuing to do commendable work and are
internationally well recognized. • In all these fields there are a sufficient number of exciting future
programs in which Indian groups can participate, both in the domestic scene as well as within the International context.
• The topmost priority in all fields would be to continue and complete the ongoing projects, which are already funded, successfully.
Astro-particle physics: • currently ongoing programmes are:
– GRAPES (TIFR) at Ooty: an ongoing TIFR experiment to determine primary composition of UHE (Ultra High Energy) cosmic ray flux over the energy range 30 TeV – 30,000 PeV. Goals are to provide insight into acceleration mechanisms of cosmic rays as well as to study particle interactions in the very forward fragmentation region. There is also a plan to install mini-GRAPES arrays at several universities in the country. Cosmic Ray studies (CORAL) using the TPC of the ALICE detector at CERN complements the studies with GRAPES.
• An already funded program (by DAE till 2012) is the Cherenkov array MACE at the Himalayan Gamma Ray Observatory (HiGRO of BARC-TIFR-IIA) near Hanle, with a very high resolution imaging camera, during 2007-12, next to the Himalayan Chandra Optical Telescope. Later expansion is planned for setting up a total of 16 element array by around 2018.
• Search for Strangelets in Cosmic Rays. A large array of solid state detectors is being installed at Sandakphu at 4200 metres altitude. This project is already funded by DST during the 2005-10 period. The group plans to expand the array during 2010-16.
• Future programs to be supported (in order of priority):
– Expansion of GRAPES
– Expansion of the MACE telescope array at HiGRO by 2018
– Expansion of Passive detector array, if needed
Thank You
Solar Structure
The number of sunspots reaches a maximum about every 11 years, successive Maxima have spots with reversed magnetic polarity. Thus the whole cycle is 22 years long.
Sunspot cycle :