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 :