'Physics' for many of us may not be a subject of interest.
It might not have incremented weightage in exams to the extent we expected it probably
would. Results were always unsatisfactory. Science was truly a 'rocket science'
and physics continued to be equally spooky. Why? Reasons possibly were the lack
of interest, and reluctance to elucidate its closeness to the nature that keeps
us all moving.
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| Meenakshi Narain |
On the other hand are those who found it interesting in Science,
‘Physics’ is exciting to them. Meenakshi Narain is one such name. She hailed
from Gorakhpur, Uttar Pradesh, India and completed her M.Sc. (in physics) from
IIT Kanpur in 1984. Meenakshi a PhD (in physics) from State University of New York,
Stony Brook is currently deputed as a Professor (physics department) in Brown
University of United States. Achievements are indeed admirable in academic
discipline of ‘physics’.
As scientific minds (usually) are, she must have been amazed
by the significant contribution that physics make in exploring this un-explored
universe. It was Albert Einstein who established the theory of ‘Modern Physics’
few decades ago, but today it is enriching our lives right from the basic home
appliances to super smart Computer systems. It had advanced beyond our
imagination to produce weaponry like nuclear bomb. And now, it claimed to have
discovered a sub-atomic particle ‘God Particle’ or Higgs Boson which is said to
be a major breakthrough in understanding of everything that surrounds us on
this universe. Thanks to Meenakshi Narain for playing an instrumental role in
this discovery which would now help physicists to observe the last ‘essential’
particle which is required by standard physics since long.
On 4th July 2012, Switzerland’s European Organization for
Nuclear Research (CERN) announced the discovery of a sub-atomic particle ‘Higgs
Boson’ or ‘God Particle’. The discovery is significant since it is a particle on
which the whole study of ‘Standard Model’ of physics stands. Having no evidence
found of its existence would mean tearing everything apart and going back to
the drawing board with completely new set theories.
‘Higgs boson’ is named after two great physicist Peter Higgs
and Satyendra Nath Bose (1894-1974). British physicist Peter Higgs had first
postulated the existence of such a particle in early 1960s. Higgs with other 6
authored ground breaking paper which is today known as Higgs Mechanism. Indian physicist
Satyendra Nath Bose is known for his excellent work in ‘quantum physics’ which
led the foundation for Bose-Einstein statistics in as early as 1920.
This discovery is made possible by ATLAS (A Toroidal LHC
Apparatus) and CMS (Compact Muon
Solenoid) experiments at Large Hadron Collider (LHC) - a ‘Big Bang’
particle accelerator. It is a gigantic device equipped with powerful monitoring
appliances and recreates conditions right after the birth of universe in a
fraction of billionth of a second. It is
26 kilometer long ring shaped pipeline constructed on Switzerland and France
border. It emanates the protons from two sides which travel at a very high
speed and collide to create a number of particles including Higgs boson. Scientist
at LHC had revealed in December the last year that they had caught the first
glimpse of Higgs boson. Since then they had sifted the large amount of data
generated by high energy collision.
Meenakshi Narain has led the group within the CMS experiment
at LHC, which is responsible for developing the algorithms to identify bottom
quarks from the signals that are collected by the detector and are used by the
entire collaboration. Identifying bottom quarks is important for the search of
the Higgs boson because a Higgs boson with a mass of 125 GeV is expected to
decay most of the time into bottom quarks. It is essential for the
characterization of the particle that we have discovered to measure whether and
how often it decays into bottom quarks. In addition together with her Brown
University team she has contributed to various aspects of detector related
projects and together with her graduate student, is involved in the analysis of
the Higgs Boson decays into a b-quark and anti-b-quark.
After the announcement at CERN, Peter Higgs who was himself
present on spot congratulated the team for this significant achievement. Wiping
tears from his eyes, he said: 'It's really an incredible thing that it's
happened in my lifetime.'
Professor John Womersley who is a Chief Executive of the
Science and Technology Facilities Council, said: ‘They have discovered a
particle consistent with the Higgs boson. Discovery is the important word. That
is confirmed. It's a momentous day for science.’
Joe Incandela who is a lab spokesman said: ‘this is indeed
a new particle, this is something that may in the end be one of the biggest
discoveries or observations of any new phenomena that we’ve had in our field in
the last 30 or 40 years,'.
A discovery usually gets authenticated by statistical standard of
proof. Among other ‘Five Sigma’ is considered as an ultimate confirmation of a
discovery. Two experiments ATLAS, CMS were conducted in this discovery of Higgs
boson.
Fabiola Gianotti, experiment spokesperson of ATLAS said: ‘We observe in
our data clear signs of a new particle, at the level of 5 sigma, in the mass
region around 126 GeV, but a little more time is needed to prepare these
results for publication.’
Joe Incandela, experiment spokesperson of CMS said: ‘The results are
preliminary but the 5 sigma signal at around 125 GeV we’re seeing is dramatic.
This is indeed a new particle. We know it must be a boson and it’s the heaviest
boson ever found’.
‘The implications are very significant and it is precisely for this
reason that we must be extremely diligent in all of our studies and
cross-checks.’
‘It’s hard not to get excited by these results,’ said CERN Research
Director Sergio Bertolucci. ‘We stated last year that in 2012 we would either
find a new Higgs-like particle or exclude the existence of the Standard Model
Higgs. With all the necessary caution, it looks to me that we are at a
branching point.’
More about ‘Higgs boson’ –
The Higgs boson, a subatomic particle was predicted by our theory of
the fundamental interactions, called the standard model. This theory starts by
postulating some fundamental symmetry principles and one can show
mathematically that these principles can only hold if there are certain
interactions between particles, in particular the electromagnetic interaction
and the weak and strong nuclear force. But the theory works only if all the
particles involved in these are massless. Experimentally we know that this is
not true. The photon which is the particle that transmits the electromagnetic
force is massless but the W and Z bosons which transmit the weak force are very
massive, 80-90 times the mass of the proton. In the early 1960’s three groups
of theorists, Englert and Brout in Belgium, Higgs in UK, and Guralnik, Hagen,
and Kibble in the US came up with a scheme that solved the problem. They
introduced another particle into the theory that would interact with all
massive particles and through this interaction these particles would receive
their masses. We have confirmed most predictions of the standard model in
experiments, except the prediction that there should be a Higgs boson. It is
still an open question whether this is the correct explanation.
The Higgs boson cannot be seen directly. It is expected to decay
instantly after it was produced. The
CMS detector is specifically designed to detect the signatures of the
Higgs boson decays. One of the decays is to two photons. The CMS detector has a
calorimeter with an excellent energy resolution which enables it to measure the
energy of these photons extremely precisely. This enables the CMS detector to
separate the Higgs decays from the background processes that also produce
photons and to measure the mass of the Higgs boson with great precision.
More about Meenakshi Narain –
Prof. Meenakshi Narain received her PhD in physics from the State
University of New York at Stony Brook. She joined the Brown faculty in 2007
having previously taught at Boston University. She enjoys helping students and
is continually exploring new ways of teaching physics to both graduate and
undergraduate students.
Prof. Meenakshi Narain's research interests are in experimental high
energy physics and her ultimate goal is to illuminate the character of physics
at the TeV energy scale. Meenakshi Narain has been involved with the CMS
experiment at the Large Hadron Collider at CERN (Geneva, Switzerland) and the
DØ experiment at Fermilab (Batavia, IL). She was instrumental in the discovery of
the top quark in 1995, which is the heaviest fundamental particle and heavy as
an Osmium atom, and has since investigated its properties. She continues her
quest at the LHC to find the Higgs Boson and is excited about the vast new
energy frontier that may enable us to make discoveries which revolutionize our
understanding of the universe.
Within CMS she is co-leading the group to identify b-quark jets, which
are expected from the decays of particles, such as the Higgs Boson and the top
quarks. She and her team are working on searching for the Higgs Boson in data
collected by the CMS experiment since 2010. The Higgs Boson is the particle
which is responsible for masses of the most fundamental particles, the quarks
and leptons. She also is very much interested in analyzing the data to uncover
a signal for a neutral heavy gauge boson, which is anticipated by models for
physics beyond the Standard Model such as SUSY, extra dimensions, Little Higgs
and Technicolor. She is also co-leading a working group at Fermilab's LHC
Physics Center that is investigating physics processes which include charged
leptons, hadronic jets and missing energy in their final state. This is a
topology where new physics can appear with a bang.
Narain is a Fellow of the American Physical Society. She has been a
Wilson Fellow at Fermilab and has received a Professional Opportunities for
Women in Research and Education grant, Major Research Infrastructure grants,
and the CAREER Award from the National Science Foundation. She is also a recipient
of the Outstanding Junior Investigator Award from the US Department of Energy.
She is a co-author on about 400 peer-reviewed journals, and has given numerous
public lectures and invited conference presentations.
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