BUILD INDUSTRIAL PAKISTAN: NEED TO EDUCATE THE YOUTH OF PAKISTAN

Understanding the formation of Universe to resolve the Energy Crisis.

Cosmologists are agreed that the universe began with a big bang. Evidence comes from the fact that the universe is still expanding today, with clusters of galaxies flying apart from each other at immense speeds. If the universe is expanding, it had to be smaller in the past.

According to the most recent measurements and observations , the time the Big Bang occurred and the age of the Universe, is calculated as approximately 13.7 billion years.

Brief about Big Bang, nucleosynthesis, and the modern search of formation of Structure of matter.

Ø In the beginning there was nothing and then Big Bang occurred. In first seconds the temperature was billions of degrees. The Cosmic soup expanded very fast and then rouhghly three minutes after Big Bang, started cooling to form photons, bosons,gluons, gravtions ,energy radiation discussed below.

Ø Temperatures further dropped and the forces devided. Up, down, top, charmed and strange quarks together with glue balls and chain to form protons and neutrons, mesons and leptons, baryons and bosons

http://www.youtube.com/watch?v=OdTTwtVcYjU

Now on Earth, Big Bang experiments are carried out in the Laboratory Particle Accelerators and experimenters have managed to recreate the extra ordinarily hot, dense medium on Earth.

http://www.youtube.com/watch?feature=endscreen&v=vwnigNSVGVw&NR=1

Ø Gravity started to form hydrogen and helium gas, coalesce to form the giant clouds that became first galaxies and stars.

http://www.youtube.com/watch?v=80eMTnnLjhs&feature=related

High density and hot temperature of early Big Bang could produce light elements Hydrogen, Isotope Deuterium, Helium, small amount of Isotope tritium, Lithium, via fusion.

Ø After next half hour, Universe cooled and expanded to point where fusion of heavier elements was impossible. Additional Heavier Elements originate in interiors of very first stars relatively late in Universe's history.

Related videos:

VIDEO-1

http://www.youtube.com/watch?v=HVxBdMxgVX0&feature=related

VIDEO-II

http://www.youtube.com/watch?NR=1&feature=endscreen&v=WGWlT8SqXLM

NUCLEUS INSTABILITY:

The nucleus of an atom contains protons and neutrons held together by the strong nuclear force. However, when there are too many or too few neutrons in the nucleus, it becomes unstable. Beta decay occurs when the ratio of neutrons to protons is too great, or too small. Neutrons can emit an electron and become a proton to stabilize this ratio. Protons can also emit a positron and become a neutron. This results in the original atom becoming a different element because the number of protons change.

Observations from the above plot:

All the stable nuclei lie within a definite area called the Zone of stability.

i) For low atomic numbers most stable nuclei have a neutron/proton ratio which is very close to 1. As the atomic number increases, the zone of stability corresponds to a gradually increasing neutron/proton ratio. In the case of the heaviest stable isotope, for instance, the neutron/proton ratio is 1.518. If an unstable isotope lies to the left of the zone of stability in Fig., it is neutron rich and decays by β emission. If it lies to the right of the zone, it is proton rich and decays by positron emission or electron capture.

ii) Another factor affecting the stability of a nucleus is whether the number of protons and neutrons is even or odd. Among the 354 known stable isotopes, 157 (almost half) have an even number of protons and an even number of neutrons. Only five have an odd number of both kinds of nucleons. In the universe as a whole (with the exception of hydrogen) we find that the even-numbered elements are almost always much more abundant than the odd-numbered elements close to them in the periodic table.

iii) Finally there is a particular stability associated with nuclei in which either the number of protons or the number of neutrons is equal to one of the so-called "magic" numbers 2, 8, 20, 28, 50, 82, and 126. Of particular stability, and also of high abundance in the universe, are nuclei in which both the-number of protons and the number of neutrons correspond to magic numbers.

Nuclear energy:

Nuclear energy is released by three exothermic processes:

i. Radioactive decay, is the spontaneous disintegration of atomic nuclei by emitting either alpha particles, Beta particles, gamma rays, (or all of them)

ii. Fusion, two atomic nuclei fuse together to form a heavier nucleus

iii. Fission, the breaking of a heavy nucleus into two (or more rarely three) lighter nuclei.

Radioactive decay

All radioactive elements (unstable) began to decay as soon as they had been created in supernova or stellar nucleosynthesis in early high temperatures and pressure conditions.

Understanding of Radiations and Radioactive Decay:

The four most common modes of radioactive decay are: alpha decay, beta decay, inverse beta decay (considered as both positron emission and electron capture), and isomeric transition. nuclei).

The step-by-step process by which radioactive elements emit alpha, Beta and gamma radiations, change into other elements and finally reach stability is called a decay series.

The time involved in radioactive decay is known as half-life (the length of time it takes for one-half of a given number of atoms of one element to decay into another element). The half lives of the isotopes formed in a decay chain may be measured in seconds, minutes, days, years, or millennia which help us in estimation of geological age of rocks.

Thorium-232, Uranium-238, and Uranium-235 have existed since the formation of the earth.

The plutonium isotopes( Pu-244 and Pu-239) have also been found in trace amounts on earth(almost all plutonium-239 and other heavier elements) thought to be consumed to form lower elements/isotopes in the early period of big bang when the temperature of the universe began to drop but still was very high for fast decomposition.

Three main decay chains (or families) are observed in nature on Earth, commonly called the radium (Uranium) series, the thorium series, and the actinium series and ending in three different, stable isotopes of Lead (206,208,207).

Mentioned below is the graph of binding energy which plots the binding energy per nucleon against atomic mass. This curve has its main peak at iron and then slowly decreases again and also a narrow isolated peak at helium, which as noted is very stable.

The heaviest nuclei in nature, uranium 235U & 238U, are unstable, but having a lifetime of 4.5 billion years for 235U, close to the age of the Earth and longer for 238U, they are still relatively abundant; they (and other nuclei heavier than iron) may have formed in a supernova explosion , preceding the formation of the solar system. The most common isotope of thorium, 232Th, also undergoes α particle emission, and its half-life (time over which half a number of atoms decays) is even longer, by several times. In each of these, radioactive decay produces daughter isotopes which are also unstable, starting a chain of decays which ends in some stable isotope of lead.

Binding Energy per nucleon plotted as a function of atomic mass number.

Observations from Average binding energy plot.

(i) Binding energy per nucleon increases from 1.1 to 8.0 MeV from mass number 2 to 20.

(ii) Binding energy per nucleon increses from 8 to 8.6 MeV from mass number 20 to 40.

(iii) Binding energy per nucleon remains 8.6 – 8.7 MeV from mass number 40 to 90. Iron (56) has the maximum value of 8.7 MeV per nucleon.

(iv) The value of binding energy per nucleon decreases from 8.6 to 7.5 MeV from mass number 90 to 240.

(v) Points for helium, carbon, oxygen lie quite high in the graph showing that these nuclei are highly stable.

(vi) A notable exception to this general trend is the helium-4 nucleus, whose binding energy is higher than that of lithium, the next heaviest element. The Pauli exclusion principle provides an explanation for this exceptional behavior—it says that because protons and neutrons are fermions, they cannot exist in exactly the same state. Each proton or neutron energy state in a nucleus can accommodate both a spin up particle and a spin down particle. Helium-4 has an anomalously large binding energy because its nucleus consists of two protons and two neutrons; so all four of its nucleons can be in the ground state.

(vii) At the peak of binding energy, nickel-62 is the most tightly bound nucleus (per nucleon), followed by iron-58 and iron-56.

Nuclear Reactions are regulated by the Nuclear Binding Energy.

Protons and neutrons are held together by the strong force, which only acts over very small distances as discussed above but is able to overcome the electrostatic repulsion between protons. The strength of the bonding is measured by the binding energy per nucleon where “nucleon” is a collective name for neutrons and protons. But the total mass of the nucleus is less than the sum of the mass of the individual neutrons and protons that formed it.

The difference in mass is equivalent to the energy released in forming the nucleus of an atom and known as the mass defect per nucleon.

Example of Helium Nucleus :

The mass of a proton is 1.00728 atomic mass units (u), while neutrons weigh 1.00866 u.

The alpha particle (helium nucleus) has less mass than the sum of the masses of the individual particles that make it up.

When the four nucleons combine, the extra mass is transformed into the energy that holds them together in the nucleus of the atom. The mass can be directly converted to energy, the binding energy of the nucleus as per Einstein's equation.

It is also the energy required to break (unbind) a nucleus into separate protons and neutrons.

The attractive nuclear force (strong nuclear force), which binds protons and neutrons equally to each other, has a limited range due to a rapid exponential decrease in this force with distance as shown in figure below and also discussed above.

The general decrease in binding energy beyond iron is due to the fact that, as a nucleus gets bigger, the ability of the strong force to counteract the electrostatic repulsion between protons becomes weaker.

For both the smaller and more massive nuclides, the stability is less. This leads to some interesting reactions.

The most tightly bound isotopes are ⁶²Ni, ⁵⁸Fe, and ⁵⁶Fe, which have binding energies of 8,8 MeV per nucleon. Elements heavier than these isotopes can yield energy by nuclear fission; lighter isotopes can yield energy by fusion.

In fusion and fission nuclear reactions, nuclear energy produces thermal energy, which is given off as heat.

Fusion Reaction:

Fusion is the production of heavier elements by the fusing of lighter elements.

Tremendous Nuclear energy inside hydrogen nuclei is released, when hydrogen nuclei fuse to form a helium nucleus. The sun and other stars use the fusion to generate radiant and thermal energy.

Here on Earth, future fusion plants will imitate the Sun, fusing deuterium and tritium atoms at temperatures over 100 million degrees K, releasing energy for a variety of uses, including electricity. Such a condition where the thermal energy of nuclei is high enough to fuse despite their repulsion is called thermonuclear. The fuel for this fusion is found in water, and can therefore provide energy for the world for billions of years. Progress in fusion research indicates fusion to be a practical energy source sometime in the 21st century (Ref: Experiment at RIKEN–RAL Muon Facility Japan & UK, mentioned below).

Fission Reaction:

Nuclear energy is released during atomic fission, when uranium nuclei are split. Fission's heat is used to generate electric power in hundreds of locations worldwide.

Atoms of the same element with a different number of neutrons are called isotopes. The isotope of uranium that is needed for nuclear fission, and therefore, nuclear energy, is Uranium-235.

This isotope is unique because it can undergo induced fission, which means its nucleus can be forced to split. This happens when a thermal neutron runs into the nucleus of U-235, which absorbs the neutron, becomes unstable, and breaks into two nuclei of

lighter elements. In the process, two or three neutrons are also released, which further collide with other U-235 atoms, causing a huge chain reaction. The amount of energy released is incredible- a pound of highly enriched uranium has about the same energy as a million gallons of gasoline.

Both fission and fusion nuclear reactions release energy by converting some of the nuclear mass into gamma-rays, this is the famous formulation by Einstein E=mc²asdiscussed above.

PRESENTLY TWO IMPORTANT EXPERIMENTS ARE IN PROGRESS BASED ON PARTICLE PHYSICS.

i) Experimenting with Neutrino.

ii) Experimenting Muon Catalyzed fusion for energy production.

i) Experimenting with NeutrinoS:

In a recent report of June 27, 2011, Fermi Lab US Discovers Clues to Why the Big Bang Produced More Matter than Antimatter.

Scientists of the MINOS experiment at the Department of Energy’s Fermi National Accelerator Laboratory US have announced the results from a search for a rare phenomenon, the transformation of muon neutrinos into electron neutrinos. The result is consistent with and significantly constrains a measurement reported 10 days ago by the Japanese T2K experiment, which could have implications for understanding of the role that neutrinos may have played in the evolution of the universe. If muon neutrinos transform into electron neutrinos, neutrinos could be the reason that the big bang produced more matter than antimatter, leading to the universe as it exists today.

The Daya Bay Reactor Neutrino Experiment China:

Source: Daya Bay Reactor Neutrino Experiment
Content: Press Release
Date Issued: 8 March 2012

From its beginnings in 2006, the Daya Bay Reactor Neutrino Experiment has established new scientific milestones as the first equal partnership between the U.S. and China in a major physics project.

Initial U.S. participation was guided by James Siegrist, then Associate Laboratory Director for General Sciences and Director of the Physics Division at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab).

Discovery of a New Kind of Neutrino Transformation.

The Daya Bay Reactor Neutrino Experiment, a multinational collaboration operating in the south of China, today reported the first results of its search that neutrinos can appear to vanish as they travel?

. The Guangdong Daya Bay Nuclear Power Station, where neutrinos are born.

Traveling at close to the speed of light, the three basic neutrino "flavors" - electron, muon, and tau neutrinos, as well as their corresponding antineutrinos - mix together and oscillate (transform), but this activity is extremely difficult to detect. From Dec. 24, 2011, until Feb. 17, 2012, scientists in the Daya Bay collaboration observed tens of thousands of interactions of electron antineutrinos, caught by six massive detectors buried in the mountains adjacent to the powerful nuclear reactors of the China Guangdong Nuclear Power Group. These reactors, at Daya Bay and nearby Ling Ao, produce millions of quadrillions of elusive electron antineutrinos every second.

Neutrinos, the wispy particles that flooded the universe in the earliest moments after the big bang, are continually produced in the hearts of stars and other nuclear reactions. Untouched by electromagnetism, they respond only to the weak nuclear force and even weaker gravity, passing mostly unhindered through everything from planets to people. The challenge of capturing these elusive particles inspired the Daya Bay collaboration in the design and precise placement of its detectors.

Each antineutrino detector at Daya Bay is lined with photomultiplier tubes to catch the faint trace of antineutrino reactions in the scintillator fluids that fill the detectors. (Photo Roy Kaltschmidt, Lawrence Berkeley National Laboratory)

The plentiful data revealed for the first time the strong signal of the effect that the scientists were searching for, a so‑called “mixing angle” named theta one-three (written θ₁₃), which the researchers measured with unmatched precision. Theta one-three, the last mixing angle to be precisely measured, expresses how electron neutrinos and their antineutrino counterparts mix and change into the other flavors. The Daya Bay collaboration’s first results indicate that sin²2 θ₁₃ is equal to 0.092( plus or minus)0.017.

This is a new type of neutrino oscillation, and it is surprisingly large,” says Yifang Wang of China’s Institute of High Energy Physics (IHEP), co-spokesperson and Chinese project manager of the Daya Bay experiment. “Our precise measurement will complete the understanding of the neutrino oscillation and pave the way for the future understanding of matter-antimatter asymmetry in the universe.”

ii) EXPERIMENTING Muon Catalyzed fusion for energy production:

Muon research at the RIKEN–RAL Muon Facility Japan & UK could lead to commercially viable fusion technology for clean energy generation.

The Rutherford-Appletion Laboratory UK (left) and the RIKEN-RAL Moun Facility Japan (right).

In the Sun's core, hydrogen nuclei move violently due to the extreme temperature, and the ultra high density resulting from the Sun's massive gravity causes the hydrogen nuclei to be forced together to within one ten-trillionth of a centimeter, inducing a chain of nuclear fusions.

Director of the RIKEN-RAL Muon Facility. Teiichiro Matsuzaki and scientists at the facility have been conducting unique experiments as part of fundamental research into the use of muons to develop industrially viable nuclear fusion technology.

To achieve nuclear fusion on Earth, Deuterium (d) and tritium (t) nuclei are used as the fuel in place of hydrogen, as these nuclei are more readily induced into nuclear fusion and the reaction releases greater energy. Whereas a hydrogen nucleus consists of just one proton, a deuterium nucleus consists of one proton and one neutron, and a tritium nucleus consists of one proton and two neutrons.

Muon-based nuclear fusion is conducted using negative muons. A mixed gas of deuterium and tritium is cooled to temperatures below around −250°C, causing the gas to form a liquid or solid. The injection of a beam of muons (µ) into the medium then generates muonic tritium atoms (tµ), which are similar to hydrogen atoms. As muons are 207 times heavier than electrons, the muon orbits the nucleus at a distance much shorter than that for electrons. Thus, tµ atoms are extremely small, and because the tµ atoms have no charge, they collide with deuterium atoms without being affected by repulsive electrical force. This process produces muonic deuterium–tritium molecules (dtµ), which are also similar to hydrogen atoms, and which have a nucleus consisting of a muon, a deuterium nucleus and a tritium nucleus. Similar to the tµ atom, the dtµ molecule is extremely small, which allows the deuterium and tritium nuclei to come into very close proximity, thus inducing d–t nuclear fusion as shown in the above figure.

Until 5–10 years ago, muon-catalyzed nuclear fusion experiments were conducted in muon facilities in the United States, Switzerland and Russia, and all achieved an energy balance of about 40%. These countries withdrew from these studies because of the decommissioning of muon facilities or a lack of experts who could deal with tritium, a radioactive material.

Director of RIKEN –RAL Teiichiro Matsuzaki says, RIKEN-RAL Muon Facility, now the only research institute in the world that continues to perform fundamental experiments on muon-catalyzed nuclear fusion, to achieve scientific break-even conditions in an effort to put nuclear fusion into practical use for energy production.

Suggestions:

Ø Need to join the research work being carried out on energy projects in friendly countries to get acquainted with the new technologies coming up for energy production.

Ø Need to upgrade our Universities to international standards and provide research facilities with proper funding.

Ø Need to boost the private sector as a driving force to invest in clean and renewable energy technologies in Pakistan.

BUILD INDUSTRIAL PAKISTAN

Friday, April 13, 2012

NEED TO EDUCATE THE YOUTH OF PAKISTAN

Discovery of a New Kind of Neutrino Transformation.

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