SCIENCE TRIBUNE Thursday, August 31, 2000, Chandigarh, India

The sun is behaving like a lamb
by Dinesh Pal Singh
CIENTISTS all over the world were much afraid of sun in the first week of March. They had declared that strong eruption from sun’s corona would release highly energetic of (MeV range) charged particles towards the earth and this release of energy might cause disasters on earth on March 2-3. 

Fourth state of matter
HYSICISTS at CERN in Geneva claim that they have finally produced a fourth state of matter — the quark gluon plasma (QGP).



The sun is behaving like a lamb
by Dinesh Pal Singh

SCIENTISTS all over the world were much afraid of sun in the first week of March. They had declared that strong eruption from sun’s corona would release highly energetic of (MeV range) charged particles towards the earth and this release of energy might cause disasters on earth on March 2-3. The gravity of their fear can be understood from the fact that such an energy release is equivalent to millions of 100 megaton H-bombs exploded simultaneously. People were cautioned against moving in the open sun mainly between 11 am and 1.30 pm as scientists were expecting, during this time interval, coming of very intense x-rays and UV radiations over-exposure of which may cause skin cancer. The scientists were fearing that almost 500 satellites orbitting the earth will be destroyed by such coronal eruptions because of which worldwide telecom devices might be defected/badly affected. But like the millennium bug, this event, too, proved a nonstarter. The disastrous solar radiations could reach up to only 25 Ro (Ro is earth radius of 6372 km) above earth without affecting earth’s environment and its magnetic field. According to analysts of the National Community and Environment Management Institute, Washington, this solar cycle had perhaps fewer than expected activities and that physicists had exaggerated the temperature enhancement in the sun.

The views of the Director, Centre for Space Environment — a branch of American Association for Advancement of Science, were that the sun was hoped to behave like a lion but it is behaving as a lamb.

The sun appears as a visible disc when seen through a telescope and its photograph taken in white light depicts many a dark spots on this disc. These spots are called sun spots. They are actually relatively cool areas on the photosphere (inner region of the sun surrounding central core) and act as foci for solar active regions. The number of spots varies with time. This change in sunspot numbers is a periodic and regular process. One period takes almost 11 years and is called a solar cycle. Suppose today this number is “N” then this number will go on increasing to reach a maximum and then will start to decrease and after 11 years, the number will again become “N”. So one “sun spot maximum” and one “sun spot minimum make one solar cycle. Sun spots are formed when matter of sun’s interior comes out. During sun spot maximum some regions in the sun appear brighter than usual. Solar flares is the name given to such regions. The flares are frequently emerging hot gases (under very high pressure) from photosphere and burst into space like burning explosive substance. During this time, the solar wind (hot gas of 105 K temperature) consisting mainly of protons and electrons (of many MeV) travelling outward from the sun at supersonic speeds of 500 km/s, exerts a pressure on earth’s magnetic field. To save earth from the intense impact of these dangerous particles, nature has made some arrangement. A bow-shock is formed at about 12 Ro away from earth. This is made at a region where kinetic pressure of solar wind is balanced by the pressure of the earth’s magnetic field. Thus effect of energetic particles is highly minimised. Even then some of these particles enter earth’s space through sides of the bow-shock (polar cap/cusp region, see figure) and follow open field lines directly to the ionosphere. Dr H.I. West and Dr A.L. Vampola after analysing data recorded aboard OGO5 and OV1 satellites during a (solar flare event” found that even these pilferingly entering particles have energy of 1.53 MeV (electrons)/80 MeV (protons) and give rise to auroras, x-rays and electromagnetic radiations.

The changes in geomagnetic field due to particles from solar storms/flares are called magnetic storms. The strength of a magnetic storm is measured in terms of earth’s horizontal magnetic field (H). When H is less than 250 gamma it is moderate storm and whenever H is more than 400 gamma, it is called severe magnetic storm. Though solar (flare) storms, sun spot numbers, solar particles’ impact on earth and magnetic storms are all co-related, maximum sun spot number does not mean maximum danger. In March, 1989, power transmission lines of Quebec, Canada were badly destroyed by solar wind rediations and public of that city had to live in total darkness for many days. The days on which maximum sun spots occurred were 14th (181) and 16th (187 spots) of March, 1989. But February had more sun spots than March — 216 on 12th, 219 on 13th. And you will be surprised to note that every day between June 13 and 16, 1989, had individually more than 250 sun spots. Nevertheless, March, 89, was a highly disturbed month as it had maximum number of magnetic storms in it; it remained disturbed for 20 days, and had two severe storms out of eight total storms that occurred.


Fourth state of matter

PHYSICISTS at CERN in Geneva claim that they have finally produced a fourth state of matter — the quark gluon plasma (QGP).

The first state of matter is what we see around us — ships, trees, cabbages and presidents (kings are scarce these days!). When this matter is put into a furnace and heated sufficiently, it breaks up into a second state of matter, some of the 92 elements, the latter so called because the scientists of that time thought that these were the ultimate elements of nature.

About a hundred years ago, Lord Rutherford and his colleagues at the Cavendish Laboratory in Cambridge found that these elements were not really elementary but were made up of the nucleons (protons and neutrons) and electrons. This is the third state of matter.

Their discoveries opened the floodgates on nuclear research, spurred by the enormous applications of such research in war. Bigger and bigger accelerators were built and in the course of time, there was convincing evidence that the so-called elementary particles, the hadrons (protons, neutrons and mesons) themselves were composite particles and were built up of quarks glued together by gluons, a fourth state of matter.

The glue is apparently so strong that quarks do not exist by themselves. Only hadrons made of certain stable combinations of quarks can be detected in the laboratory.

It had already been observed that at a temperature of a few million degrees, matter dissolved into a plasma of hadrons. Such a plasma exists deep inside the sun and other stars.

Astrophysicists believe such a plasma was created minutes after the Big Bang, the tremendous explosion that created our universe. What sequence of events culminated in this plasma became the next intriguing question. A study of the various stages of evolution between the Big Bang and the hadron plasma would tell us of the first seconds of the birth of the universe. It is now almost certain that the primeval energy of the Big Bang quickly converted into a plasma of quarks and gluons that then coagulated into hadrons.

The efforts of several groups of physicists from around the world have been towards producing this early fourth state of matter. To produce a quark-gluon plasma is not an easy task, but once produced in the laboratory,a detailed investigation of the properties and behaviour of the quarks and gluons within it can be made. One big difference between the laboratory-made plasma and the original one is that the latter was enormous where the constituents were well mixed in a thermodynamic soup with negligible surface effects.

A few years ago, two physicists from Mumbai showed that quarks could be liberated, albeit temporarily when a proton and an anti-proton suffered a head-on collision at very energies. During this collision all the energy is compressed into a small volume and the temperature inside it shoots up enough to release the quarks from their confinement within the hadrons.

If instead of protons, heavy nuclei, for instance lead with 208 nucleons, were to collide head on with anti-lead nuclei, the fireball would be much larger and one might find that the quarks and gluons thermalised as in the original quark-gluon plasma. Since anti-lead will not be available for a long time. Collision of lead nuclei speeding along opposite directions was examined at the large CERN accelerator.

Most of the collisions that occurred were sideswipes and the rare head-on collisions had to be sieved out of the data. Head-on or central collisons are marked by the large number of fragments that emerge at right angles to the beam direction, in much the same way that the head-on collision of two vehicles scatter glass and metal on the road. Such criteria have been used to filter out interesting events from the vast amount of data that is collected during the experiment.

Theoreticians suggest that the best signals come from an observation of charmed particles (particles that contain charmed, or c-quarks) from central collisions.

One of the signals that uniquely indicate that a quark gluon plasma is formed is the excess production of charm particles. The latest results find evidence that this production is abnormally increased in properly selected events.

In a hot brew of quarks and gluons, energy is continually converted to particles and anti-particles. Quarks and anti-quarks are produced and annihilated. So, when c-quarks and anti-c-quarks are created, they sometimes combine to form a J-psi meson (some call it J and others call it psi). Inside a mob of hadrons, they escape from the collision, but if a plasma were formed, there is a possibility that these quarks get re-absorbed into the soup.

So physicists look for J-psi mesons with low momentum along the beam directon and if there is a suppression of the numbers, that is an indication of the presence of a quark-gluon plasma.

There are indications of such suppression in the recent CERN results. However these results have yet to be confirmed with much greater statistics and new measurements have to be made at higher intensities and energies. — PTI

New products & discoveries

Award-winning Machine

THE innovative style and technology behind this V5-10 computer numerical control (CNC) machining centre have earned it the British Design Council Award.

Widely used for the production of precision engineering components, the machine is made up of separate units to allow higher quality control, faster building times and minimum maintenance.

Designed for ease of operation and added flexibility for the customer, the V5-10’s advanced microprocessor-based computer electronics gives fast accurate curving of intricate components and easy, more rapid change from one cutting action to another.

The machine’s 30-station automatic toolchanger has a single arm mechanism which moves tools from the magazine to the machine spindle in one 270 degree movement. This provides a wide variety of programmed actions such as milling, drilling, boring and tapping.

The coolant is pumped in and it helps to clear the cutting surface. Compact microprocessor electronics built into the main column eliminates the need for a separate free-standing electronics cabinet, saving considerably in floor space.

Low-cost fertiliser substitute

SCIENTISTS have developed a low cost and effective substitute for an well known fertiliser, diammonium phosphate (DAP) by using high grade rock phosphate directly as fertiliser with farmyard manure.

The newly developed low grade product was successfully tested as direct application fertiliser, scientists of the Phosphate Research and Development Centre (PRDC) and Department of Botany at the MLS University in Udaipur, said.

Its utility had been proved on the basis of experimentation and the yield responses obtained during pot culture studies on wheat and gram showed that desirable results could be achieved by direct use of high grade rock phosphate concentrated with farm yard manure.

The joint research supported by the Rajasthan State Mine and Minerals Limited (RSMML) further showed when applied with farm yard manure it is as effective as DAP in natural and alkaline soils.

On the basis of these tests RSMML has introduced this low-cost fertiliser in the market, which is being tested in six different agro-climatic zones to ensure its effectiveness in acidic soil.


Science Quiz
by J.P.Garg

1. For which major contribution is the German mathematician and astronomer Johannes Kepler well-known? Name also the book which he wrote in 1609 in which he hypothesised travel to the moon, hindrances between the earth and the moon, problems of space travel, etc.

2. REMSAT is a project of the 15-nation European Space Agency which involves the use of space technology to control forest fires. What is the full name of this project?

3. This deadly but rare disease is often confused with falciparum malaria and dengue and is suspected to be caused by closeness to pet birds and animals like street dogs. It causes fever for weeks, enlargement of liver, fluid in lungs, severe abdominal pain and pneumonia. Can you name this disease which took more than two dozen lives in Mumbai recently and hit Delhi also?

4. The smallest machine of the world designed recently by the US and British scientists jointly is a “biological machine” of size of the order of one millionth part of that of the tip of a needle. What does this machine comprise?

5. This branch of science deals with the communication and control systems in animals, organisations and machines. It uses analogies between processes in the brain and nervous system and those in computers and other electronic systems. What is this study called which combines aspects of mathematics, computer technology information theory and psychology?

6. “Lye” is a strongly alkaline solution which is used in the hydrolysis of oils and fats. Originally it referred to potassium carbonate (potash) but now this term applies to a different chemical. Which is this chemical?

7. This plant contains an oil called eugenol which has antibactorial, antifungal and antimalarial properties. Its leaves also contain ascorbic acid, carotene, calcium, phosphorus and some oxalates. Its intake is useful in cold, cough, fever and some other ailments. Which is this plant that is in full bloom these days?

8. Suppose at some place we install a solar distillation plant, a solar home lighting and a street lighting system, a solar photovoltaic water pump, a solar TV set, a solar geyser, a solar lantern, etc. What name will you give to such a place?

9. Within a single water molecule, hydrogen and oxygen are held together by strong covalent bonds. What type of bonds exist between neighbouring water molecules in ice?

10. India has performed exceedingly well in the International Olympiads held recently in Physics, Chemistry and Biology, with 12 out of 13 participants winning medals and the 13th securing an honourable position. The basic tests for finally entering into these Olympiads are the National Standard Examinations in these three subjects. Which all - India organisation conducts all these three standard examinations on behalf of government of India?

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