Saturday, November 16, 2019

The Strong Nuclear Force | Essay

The Strong Nuclear Force | Essay Youssef El Laithy One of the most extraordinary simplifications in physics is the fact that only four distinct forces are responsible for all the known spectacles that go on in the universe. These four basic forces are the electromagnetic force, the gravitational force, the weak nuclear force and the strong nuclear force. Since the weak and the strong force act over an extremely short range, (less than the size of a nucleus), we do not experience them directly. Even though we don’t directly experience these forces they are vital to our existence. These forces determine whether the nuclei of certain elements will be stable or will deteriorate, and they are the basis of the energy release in many nuclear reactions. The forces determine not only the stability of the nuclei, but also the abundance of elements in nature. The properties of the nucleus of an atom are determined by the number of electrons the atom has. The number of electrons in an atom, therefore, determines the chemistry of the atom. The gravitational force is responsible for holding together the universe at large, the atmosphere, water, and us; humans, to the planet. The electromagnetic force governs the atomic level phenomena, binding electrons their atoms, and atoms to other atoms in order to form molecules and compounds. The weak nuclear force is responsible for certain types of nuclear reactions. The fourth and last force, the strong nuclear force is responsible for holding the nucleus together. The Strong Force is also one of the four fundamental forces of nature, experienced by particles called quarks and sub particles made up of quarks. It is theforce that causes the interaction responsible for binding and holding protons and neutrons together in the atomic nucleus of a given element. The strong force is the strongest of among all the other forces forces, being approximately 100 times as strong as the electromagneticforce. It has the extremely short range to which it has an effect. A range of approximately 10^-15 m, less than the size of the atomic nucleus. The strong force is carried by particles called gluons; that is, when particles interact through the strong force, they do so by exchanging gluons. The protons in a nucleus must experience a repulsive force from the other protons in the nucleus.This is where the strong nuclear force comes into play. The strong nuclear force is created between the nucleons (protons and neutrons) by the exchange of particles called mes ons. This exchange can be compared to constantly hitting a tennis ball or a footballback and forth between two people. As long as these particles (mesons) are in motion back and forth, the strong force is able to hold the participating nucleons together. Thenucleons, however; mustbe extremely close to each other in order for this exchange of mesons to occur. The distance requiredfor the force to take place and have an effectis roughly about the diameter of a proton or a neutron. Thus, if a proton or neutron can get closer than this distance to proton on neutron, the exchange of mesons occurs normally and the force has an effect. However,if they cant get that close, the strong force is too weak to make them bind together and thus the force won’t have an effect and the nucleus would rapture. The range of the Strong Force varies from where it takes place. The strong interaction is apparent in two areas: On a large scale (about 1 to 3 femtometers ), it is the force that binds protons and neutrons (nucleons) together to form the nucleus of an atom . On a smaller scale (less than about 0.8 femtometers, the radius of a nucleon), it is the force (carried by gluons ) that holdsquarkstogether to form protons, neutrons, and other hadron particles. The discovery of the Strong of the nuclear force was a remarkable discovery and cleared up lots of mysteries that haunted many physicists in this era. The discovery force wasn’t all at once; meaning that the discovery was based on the work of more than once scientist and physicist all over the years. The first discovery was by James Chadwick. In 1932, British physicist James discovered that the nucleus of atoms contain neutrons. Soon after this discovery, the American-Hungarian physicist, Eugene Wigner suggested that the electromagnetic force wasn’t the force responsible forholding the nucleus together and he also suggested that there are two different nuclear forces not just one.Later on,In 1935 Japanese Yukawa Hideki reasoned that since the strong nuclear force and weak nuclear force had never been noticedor observed by the bare eye or even by microscopesthey must act over a range smaller than the diameter of the atomic nucleus.Yukawa developed the first field theory ofthe strong force with a new particle he called mesons as the force carryingsimulated particle. From these facts and hypothesizes, Hideki Yukawa concluded that there exists a force that binds nucleons (protons and neutrons) together. He named the force the â€Å"strong nuclear force† because it had to be stronger than the electromagnetic force that would otherwise push the nucleons apart. In everyday life and our day to day life, were only aware of two fundamental forces: gravity and electromagnetism. Physicists know about two more forces, which are carried out within the atom itself (inside atoms): the strong nuclear force and the weak nuclear force.Try and imaginetwo protons (positive charge), they are pulled together by the strong nuclear force (as long as they are within range to start with). But the electromagnetic force pushes them away from each other, because they both have the same positive electric charge. When we talk about the uses if the strong nuclear force we can’t really find a direct use in which humans use the force. The only direct use is that the binding energyrelated to the strong nuclear force is used innuclear powerandnuclear weapons. The strong nuclear force is crucial to our everyday survival, God created this force exactly to suit our survival. Following this notion two questions are raised: What would happen if the strong nuclear force were a bit weaker? If the strong force were even slightly weaker than what it is, it would not be able to hold the atomic nuclei together against the repulsion of the electromagnetic force. According to Barrow and Tipler: `Ifthe Strong Force was decreased by 50% its normal power thiswould adversely affect the stability of all the elements essential to living organisms and biological systems. A bit more of a decrease, and there wouldntbe any stable elements except hydrogen. What would happen if the strong nuclear force were a bit stronger that what it is? According to Borrow and Tipler: â€Å"If the strong nuclear force was just a bit stronger compared to the electromagnetic force, two protons could stick togetherdisregardof their electromagnetic repulsion (forming a diproton).If this happened, all the hydrogen in the universe would have been burned to helium. If there were no Hydrogen in the universethere would be no water, for a start, and there would be no long-lived stars like the sun. (Stars made from helium burn up much more quickly than stars made from hydrogen).† In conclusion, The Strong Nuclear force is one of the four fundamental forces found in nature. The strong nuclear force is responsible for holding the neutrons and protons in the atomic nucleus. The interactions are experienced only by particles called quarks and by elementary particles made from quarks (mesons, gluons). The discovery of the strong nuclear force was possible by the collective work of many physicists over many years. The strong force isn’t of that much of direct use for humans. However, the force is crucial to our everyday life. If the strong nuclear force was slightly even weaker than it is, all the chemical elements needed for life would not be stable, and we, humans, would not seize to exist. The strong force isnt of that much of direct use for humans. However, the force is crucial to our everyday life. Ifthe strong nuclear force was weaker than it is, the chemical elements needed for life wouldn’t be stable, and we would not be here. On the other han d, if it were even slightly stronger than it is, all the hydrogen in the universe would have been burned in the big bang. As a result, there would be no prolonged stars like the sun, and no molecules like water. There would probably be no complex chemistry in the universe, and we would not seize to exist. Citations Fundamental Forces.Fundamental Forces. N.p., n.d. Web. 29 Nov. 2013.> . The Nucleus.The Nucleus. N.p., n.d. Web. 10 Dec. 2013.> . The Four Fundamental Forces.ThinkQuest. Oracle Foundation, n.d. Web. 9 Dec. 2013.> . The Strong Nuclear Force.The Strong Nuclear Force. N.p., n.d. Web. 1 Dec. 2013.> . The Strong Nuclear Force.The Star Garden. N.p., n.d. Web. 13 Dec. 2013.> . Nuclear Forces.Nuclear Forces. N.p., n.d. Web. 13 Dec. 2013.> . National Power Or Military Power? National Power Or Military Power? The international system today is an interplay of national power of different nations. This can be felt in the emerging world order. There has been a perceptible change, particularly during the last two decades, in the manner the nation states conduct international relations. Military alliances have given way to multilateral groupings, understandings and strategic partnerships. Nations are becoming increasingly aware of the power or influence that they wield vis-à  -vis other nations.  [1]   They are also looking at the ways and means to use this national power to secure their vital interests. In the later part of last century, National Power was only considered to be military power as can be understood by the superpower status of Soviet Union. But the disintegration of the Soviet empire and changing face of world relations due to economic globalization changed the world perception and brought the term Comprehensive National Power. This term was more inclusive of the overall state of the affairs of a nation and a measure of its constituents could indicate the strength and weaknesses.  [2]   National Power has tangible and intangible elements. Geography, natural resources, industrial capacity, population, military power form the tangible parts while national character and morale complete the intangibles. Indias economy has contributed in the last two decades towards a major share of the National power. In fact, India has even demonstrated certain soft power by cooption and attraction of other nations to achieve some of its aims. The primary currencies of soft power are an actors values, culture, policies and institutions. Indias soft power is based on its social and cultural values, the Indian Diaspora abroad and its knowledge base. India is being considered a knowledge superpower and is well placed to leverage its position in international relations. However, the military has also contributed towards the soft power. A well-run military has been a source of attraction, and military-to-military cooperation and training programmes, for example, have established transnation al networks that enhance countrys soft power. METHODOLOGY Statement of Problem The growth notwithstanding, India cannot afford to be satisfied with its current status. The geopolitical situation in the region is unstable. Though Pakistan has fewer options left after it has been exposed as a hub of terror activities and a haven for wanted terrorists, still if cornered by the world pressure and the internal compulsions it will not think twice in a military option against India to divert the attention and bring in its all weather friend , China, into the picture. India can achieve its national aims only if the internal and external threats to its security is ensured. This situation can be understood with an analogy to game of soccer; a team may be having the best of strikers in their forward and midfielder players, who can score goals at will, but their efforts are inconsequential if the goalkeeper is not trained and equipped to save goals from adversary. Thus, in the changing geopolitical situation, it is pertinent to evaluate the share of constituents of National Power to ascertain the future dynamics of a nations aspirations and interests and the regional environment. India has already made tremendous progress in various fields to achieve soft power constituent to contribute towards National Power. Indian economy is showing positive growth and attracting strategic partnership with leading economies around the globe.India , now needs to develop the military constituent to further pursue its National aim. Hypothesis India needs to develop a potent Military capability by the year 2025 to be able to assert its National Power in keeping with the stated National objectives. Methods of Data Collection 9. The data for this dissertation has been collected from a large number of books, periodicals, magazines, newspapers, internet and research journals that are available in the Defence Services Staff College library. The data related to Indian Military Power has been collected from open sources only so as to avoid any classified information to be brought out. The Bibliography is attached as Appendix. Organisation of the Dissertation Apart from a chapter on the introduction and methodology, the dissertation has been organized under the following chapters:- CHAPTER 2. CONSTITUENTS OF INDIAN NATIONAL POWER Section 1. National Power. Section 2. Indias National Power. Section 3. Constituents Of Indian National Power. CHAPTER 3. MILITARY POWER Section 1. Elements of Military Power. Section 2. Present State Of Indian Defence Forces. Section 3. Defence Budget And Modernisation Program. CHAPTER 4. SHORTCOMINGS OF INDIAS MILITARY POWER Section 1. Analysis. Section 2. Intra Organisaton Level. Section 3. Shortcoming As A National Instrument. Section 4. Recommendations . CHAPTER 5. DESIRED NATIONAL POWER BY 2025 Section 1. Geopolitical situation and regional environment In 2025. Section 2. Indias Predicted Growth By 2025. Section 3. Desired National Power. Chapter 2- Examining the constituent of Indian National Power. The present Indian standing in the world order is based on the soft power developed and the economic growth achieved by India. India as rising economy, offers excellent investment opportunity to the world. The democratic form of governance also projects India as stable and secure investment site in the long run. However we need to examine the constituents and their present share towards National Power. Chapter 3- Military Power. It itself comprises the tangibles and the intangibles. It can be broadly categorized in force capability and force employment. There has been a change in war fighting. The technological advancement ,weapon lethality, destructiveness and precision along with the information frontier has increased the cost factor of going to war. Thus there is a need to analyse the military power constituents to understand the importance towards national Power. Chapter 4- Analysis and Short comings of Indian Military Power. To suggest steps towards projecting a stronger military power the present capability needs to be analysed and the shortcoming to be highlighted. Chapter 5- Desired National Power by 2025. The regional environment in the near future entails proactive approach by India to project comprehensive national power to have secured borders and assured growth to achieve its national aims . CHAPTER 2 CONSTITUENTS OF NATIONAL POWER National Power 1. The international system an interplay of national power of different nations. There has been a perceptible the manner the nation states conduct International relations. Military alliances have given way to multilateral groupings, understandings and strategic partnerships. Nations are becoming increasingly.aware of the power or influence that they weild.vis-à  -vis other nations. 2. During 1960 and 70s most theorists.doing research on international relations avoided dealing.with phenomenon of power. National power was considered synonymous.with military power. This would explain to a great extent the superpower status.of erstwhile Soviet Union and its unexpected disintegration. Since then perception of national power.has undergone a change. It is called as comprehensive National power by the theorists which is a more inclusive term comprising all the facets of a nations resources which contribute towards its security. Defining National Power 3. National power is the ability of a nation with the use of can get its will obeyed by other nations. It involves the capacity to use force.or threat of use of force over other nations. With the use of national power, a nation is able to control.the behavior of other nations in accordance with its own will. In other words, it denotes the ability of a fulfill its national goals. It also tells us how much powerful or weak.a particular nation is in securing its national goals. Basic Elements Of National Power 4. The basic elements of national power include diplomacy, economics, informational, soft power and the age old trustworthy element of military power. It can also be classified as comprising of tangible elements and intangible elements. Geography, natural resources, industrial capacities, population, military power form the tangible elements of national power and national character and morale complete the intangibles. Indias National Power 5. In international politics, the image of India till recently used to be in terms.of its perennial rivalry with Pakistan and as power confined to South Asia only. However, as result of the remarkable Indias national strength over the last decade, consisting of.its hard and soft powers, the world has started rehyphenating India.with a rapidly growing China. The term rising India is a buzzword in the International Relations discourse nowadays. Indias national power has begun to rise steadily.since Pokhran-II. India unleashed a slew of path-breaking quick succession in 1998 (and beyond). It was from this year onwards that the idea of India being a great power,.first floated by Nehru, started to be reflected in its foreign policy. Admittedly, India shifted its foreign and economic policies.soon after the end of the Cold War in 1991 when it started broadbasing.its diplomacy, initiated economic reforms by dismantling the economic model.based on import substit ution, and went for market friendly policies. The economic reforms did give India economic the sense that India started growing at 6% annually.ever since the economic liberalization of early 1990s, however, political stability remained fragile. The country got much-needed political the center in March 1998 and a series of radical initiatives in quick succession beginning with the nuclear tests in the Pokhran desert of Rajasthan on May 11th and 13th 1998, was a grand strategic masterstroke by independent India. India initiated Multi-aligned/Great power diplomacy.for the first time in its independent history when it developed strategic partnerships.with all the great powers simultaneously, especially its relations with the United States and Japan, while retaining time-tested ties with Russia. India made institutional arrangements to its national security.when it set up the National Security.Advisory Board, National Security.Council, Nuclear Command Authority, developed a.nuclear doctrine, and so on. 6. More importantly, India developed a much needed strategic vision.whereby it redefined its geo-strategic.construct well beyond the mainland of South Asia. The comprehensive geo-strategic.construct included the Indian Ocean, the Middle East, Central Asia and the Asia-Pacific. In fact, the 1998 nuclear tests themselves were indicative of the fact that India had begun to appreciate the role of hard power in securing its national interests and also in making her influence heard in international politics. 7. The India, that China 1962 was guided by a foreign policy canon of non-alignment.vis -à  -vis the superpower enmity, and it remained the cornerstone of Indias international.diplomacy for more than four decades. However, this foreign policy paradigm underwent.a U-turn when it metamorphosed into poly/multi-alignment under the new New Delhi in 1998. The new foreign policy outlook.broadly had two components, namely, improving relations with the US and its Look East Policy-II. The turnaround in India-US relations from being estranged democracies during the Cold War to engaged democracies in the 2000s has played a central role in bringing out a shift in Chinas India posture over the last decade. India has been a democracy right since its birth as a modern nation-state in 1947. However, its sluggish economic growth and weak military profile that led to its defeat in 1962 seriously stained this aspect of Indias soft power. 8. With the rising India story, its democracy as an important component of its soft power has again come into the global limelight. India has more than 1 billion people. It is linguistically, culturally, racially, and religiously diverse, and it is growing economically at an enviable pace under democratic governmental institutions (except for the emergency period of 1975-77 when civil liberties were undermined). Its culture values peaceful coexistence, nonviolence, and religious tolerance. All of these factors, combined with the largest pool of English speakers outside the US, has increased Indias power of attraction without need for coercion or persuasion, a fact not lost on an envious, hard power-minded China. The country to which India has projected most of its soft power is the US, through the export of highly skilled manpower, consisting mainly of software developers, engineers, and doctors. 9. In military terms, post-1998 India has been enjoying strategic capital, in the sense that, unlike the rise of China, Indias military rise is not only not feared but it is felt to be desirable by the countries in the Asia-Pacific like Japan, Australia, South Korea, and ASEAN as a group. Most importantly even the US sees Indias military rise in its own interests.28 Interestingly, a rising India is making full use of this capital by emerging as a formidable military power over the last decade, apart from unveiling even more ambitious military plans for the future CHAPTER 3 MILITARY POWER Military Power 1. Military Power is military dimension of national power. National power embodies soft persuasive or attractive elements as well as its hard or military component. Military power can itself mean different things in different contexts; as military forces do different things ranging from defending national territory to invading other states; countering terrorists or insurgents, keeping the peace, enforcing economic sanctions, maintain domestic order. Proficiency in one task does not entail proficiency in all as good defenders of national territory can make poor peacekeepers and also may not be able to conquer neighbours. 2. Since beginning of civilization, military power has been the primary instruement nation states have used to control and dominate each other. With the growth of technology, the destructiveness of military power has reached apocalyptic proportions. 3. Throughout history, military power has been paramount and economic power a luxury. This has slowly changed to the point that the two roles have been reversed. Japan, China have relied on economic prosperity to finance formidable military forces. Conversely, erstwhile Soviet Union, Iraq and North Korea have relied on their military to build economic power with little or limited success. 4. Military power is the capacity to use force or threat of force to influence other states. Components of military power for a nation include number of military formations, armaments, organization, training, equipment, readiness, deployment and morale. Elements of Military Power 5. Elements of military power are worked out on the basis of military capability of nations. It includes numerical preponderance, technology and force employment. . Numerical preponderance has been exemplified in yesteryears; Napolean said , God is on the side of the big battalion 6. It is generally believed that states with larger population, more developed economies, larger military should prevail in battle. This is association of victory with material preponderance and beneath this lies the widespread perception that economic strength is precondition for military strength; that economic decline leads to military weakness and that economic policies merit co equal treatment with political and military considerations in national strategy making. Military preparedness requires a military (establishment) capable of supporting the foreign policy of a nation. Contributory factors are technology,leadership, quality and size of the armed forces. (a) Technology. The development and adoption of firearms, tanks, guns and aircraft have had a profound effect on the course of battles. To illustrate, if one reads the review of British operations during the initial stages of the Second World War, which Churchill gave in the secret session of parliament on 23 April 1942,one is struck by the fact that all defeats on land, on sea and in air have one common denominator-the disregard of technological capabilities being developed by Germans and the Japanese during the pre-war years. The U-boats played havoc with the British shipping and adversely affected their ability to move forces from one theatre of war to another, as also to sustain them. Conversely, the development of radar technology by the British during the war years gave them enormous advantage over their enemies. In the present-day context, capabilities in cyber warfare, space assets and smart strike weapons will give a great edge to the powers that are able to develop and operationalise such technologies. (b) Leadership. The quality of military leadership has always exerted a decisive influence upon national power. We have the examples of the military genius of Fredrick the Great, Napoleon, the futility of Maginot Line psychology of the French General Staff versus the blitzkrieg adopted by the German General Staff, and closer home the effect of superior military leadership led by Field Marshal SHFJ Manekshaw in Indias 1971 War with Pakistan. (c) Quality and Size of the Armed Forces. The importance of this factor is obvious. However, the question that has to be answered by the political leadership of the country is, how large a military establishment can a nation afford in view of its resources and commitments or national interests? CHAPTER 4 SHORTCOMINGS OF INDIAN MILITARY POWER Much has been written and said about the potential for Indian military power to play a greater role on the world stage, and perhaps check Chinas expanding capabilities in the future.National Security has attained multi-faceted dimensions with wider challenges in diverse fields.There has been growing understandings of these challenges and consequently measures are being taken to overcome the same. Indias remarkable economic growth and newfound access to arms from abroad have raised the prospect of a major rearmament of the country. But without several policy and organizational changes, Indias efforts to modernize its armed forces will not alter the countrys ability to deal with critical security threats. Indias military modernization needs a transparent, legitimate and efficient procurement process. Further, a chief of defense staff could reconcile the competing priorities across the three military services. Finally, Indias defense research agencies need to be subjected to greater ove rsight. Indias rapid economic growth and newfound access to military technology, especially by way of its rapprochement with the United States, have raised hopes of a military revival in the country. Against this optimism about the rise of Indian military power stands the reality that India has not been able to alter its military-strategic position despite being one of the worlds largest importers of advanced conventional weapons for three decades. Civil-military relations in India have focused too heavily on one side of the problem how to ensure civilian control over the armed forces, while neglecting the other how to build and field an effective military force. This imbalance in civil-military relations has caused military modernization and reforms to suffer from a lack of political guidance, disunity of purpose and effort and material and intellectual corruption. The Effects of Strategic Restraint Sixty years after embarking on a rivalry with Pakistan, India has not been able to alter its strategic relationship with a country less than one-fifth its size. Indias many counterinsurgencies have lasted twenty years on an average, double the worldwide average. Since the 1998 nuclear tests, reports of a growing missile gap with Pakistan have called into question the quality of Indias nuclear deterrent. The high point of Indian military history the liberation of Bangladesh in 1971- therefore, stands in sharp contrast to the persistent inability of the country to raise effective military forces. No factor more accounts for the haphazard nature of Indian military modernization than the lack of political leadership on defense, stemming from the doctrine of strategic restraint. Key political leaders rejected the use of force as an instrument of politics in favor of a policy of strategic restraint that minimized the importance of the military. The Government of India held to its strong anti-militarism despite the reality of conflict and war that followed independence. Much has been made of the downgrading of the service chiefs in the protocol rank, but of greater consequence was the elevation of military science and research as essential to the long-term defense of India over the armed forces themselves. Nehru invited British physicist P.M.S. Blackett to examine the relationship between science and defense. Blackett came back with a report that called for capping Indian defense spending at 2 percent of GDP and limited military modernization. He also recommended state funding and ownership of military research laboratories and established his protà ©gà ©, Daulat Singh Kothari, as the head of the labs. Indian defense spending decreased during the 1950s. Of the three services, the Indian Navy received greater attention with negotiations for the acquisition of Indias first aircraft carrier. The Indian Air Force acquired World War II surplus Canberra transport. The Indian Army, the biggest service by a wide margin, went to Congo on a UN peacekeeping mission, but was neglected overall. India had its first defense procurement scandal when buying old jeeps and experienced its first civil-military crisis when an army chief threatened to resign protesting political interference in military matters. The decade culminated in the governments forward policy against China, which Nehru foisted on an unprepared army, and led to the war of 1962 with China that ended in a humiliating Indian defeat. The foremost lesson of 1962 was that India could not afford further military retrenchment. The Indian government launched a significant military expansion program that doubled the size of the army and raised a fighting air force. With the focus shifting North, the Indian Navy received less attention. A less recognized lesson of the war was that political interference in military matters ought to be limited. The military and especially the army asked for and received operational and institutional autonomy, a fact most visible in the wars of 1965 and 1971. The problem, however, was that the political leadership did not suddenly become more comfortable with the military as an institution; they remained wary of the possibility of a coup detat and militarism more generally. The Indian civil-military relations landscape has changed marginally since. In the eighties, there was a degree of political-military confluence in the Rajiv Gandhi government: Rajiv appointed a military buff, Arun Singh, as the minister of state for defense. At the same time, Krishnaswami Sundarji, an exceptional officer, became the army chief. Together they launched an ambitious program of military modernization in response to Pakistani rearmament and nuclearization. Pakistans nuclearization allowed that country to escalate the subconventional conflict in Kashmir while stemming Indian ability to escalate to a general war, where it had superiority. India is yet to emerge from this stability-instability paradox. The puzzle of Brasstacks stands in a line of similar decisions. In 1971, India did not push the advantage of its victory in the eastern theatre to the West. Instead, New Delhi, underuberrealist Prime Minister Indira Gandhi, signed on to an equivocal agreement at Simla that committed both sides to peaceful resolution of future disputes without any enforcement measures. Indias decision to wait 24 years between its first nuclear test in 1974 and the second set of tests in 1998 is equally puzzling. Why did it not follow through after the 1974 test, and why did it test in 1998? Underlying these puzzles is a remarkable preference for strategic restraint. Indian leaders simply have not seen the use of force as a useful instrument of politics. This foundation of ambivalence informs Indian defense policy, and consequently its military modernization and reform efforts. To be sure, military restraint in a region as volatile as South Asia is wise and has helped persuade the great powers to accommodate Indias rise, but it does not help military planning. Together with the separation of the armed forces from the government, divisions among the services and between the services and other related agencies, and the inability of the military to seek formal support for policies it deems important, Indias strategic restraint has served to deny political guidance to the efforts of the armed forces to modernize. As wise as strategic restraint may be, Pakistan, Indias primary rival, hardly believes it to be true. Islamabad prepares as if India were an aggressive power and this has a real impact on Indias security. Domestic And Regional Constraints India faces several daunting domestic and border challenges within its own neighborhood that may prevent it from thinking more globally including the unresolved issue of Kashmir, an increasingly grave Maoist threat, Islamic terrorism from Pakistan, and unresolved border issues with China which broke out in war in 1962. Beijings effort to beef up its presence in South Asia is also seen as challenging Indian dominance there. The Lack of Strategy Indias military modernization remains, and likely will continue to be, an a-strategic pursuit of new technology with little vision. There is a whole host of problems that the nation faces, including: Little political guidance from the civilian leadership to the military. This is true even on the general issue of what Indias major goals should be. Even the Indian navy, which is often assumed to be the most forward thinking institution within Indias military, does not see itself as more than a naval blockade vis-à  -vis Pakistan. Lack of organizational and institutional reforms. The need to reprioritize resources is never addressed, what is addressed is the procurement of new material, thus making modernization merely an exercise in linear expansion. No legitimate and transparent procurement system. As a result, purchases are often ridden with scandals, corrupt, delayed and highly politicized. Indias Defense Research and Development Organization (DRDO) is also a failed organization that is ideologically corrupt, but there has not been an honest attempt to put it under public scrutiny. Imbalance in Civil-Military Relations What suffices for a military modernization plan is a wish list of weapon systems amounting to as much as $100 billion from the three services and hollow announcements of coming breakthroughs from the Defense Research and Development Organization (DRDO), the premier agency for military research in India. The process is illustrative. The armed forces propose to acquire certain weapon systems. The political leadership and the civilian bureaucracy, especially the Ministry of Finance, react to these requests, agreeing on some and rejecting others. A number of dysfunctions ensue. First, the services see things differently and their plans are essentially uncoordinated. Coming off the experience of the Kargil war and Operation Parakram, the Indian Army seems to have arrived at a Cold Start doctrine, seeking to find some fighting space between subconventional conflict and nuclear exchange in the standoff with Pakistan. The doctrine may not be official policy, but it informs the armys wish list, where attack helicopters, tanks and long-range artillery stand out as marquee items. The Indian Air Force (IAF), meanwhile, is the primary instrument of the countrys nuclear deterrent. The IAFs close second role is air superiority and air defense. Close air support, to which the IAF has belatedly agreed and which is essential to the armys Cold Start doctrine, is a distant fourth. The Indian Navy wants to secure the countrys sea-lanes of communications, protect its energy supplies and guard its trade routes. It wants further to be the vehicle of Indian naval diplomacy and sees a role in the anti-piracy efforts in the Malacca Straits and the Horn of Africa. What is less clear is how the Indian Navy might contribute in the event of a war with Pakistan. The navy would like simply to brush past the problem of Pakistan and reach for the grander projects. Accordingly, the Indian Navys biggest procurement order is a retrofitted aircraft carrier from Russia. Indias three services have dramatically different views of what their role in Indias security should be, and there is no political effort to ensure this coordination. Cold Start remains an iffy proposition. Indias nuclear deterrent remains tethered to a single delivery system: fighter aircraft. Meanwhile, the Indian Armys energies are dissipated with counterinsurgency duties, which might increase manifold if the army is told to fight the rising leftist insurgency, the Naxalites. And all this at a time when the primary security threat to the country has been terrorism. After the Mumbai attacks, the Indian government and the people of India are said to have resolved to tackle the problem headlong, but today the governments minister in charge of internal security, Palaniappan Chidambaram, is more under siege himself than seizing the hidden enemy. Second, despite repeated calls for and commissions into reforms in the higher defense structure, planning, intelligence, defense production and procurement, the Indian national security establishment remains fragmented and uncoordinated. The government and armed forces have succeeded in reforms primed by additions to the defense budget but failed to institute reforms that require changes in organization and priorities. The Kargil Review Committee, and the Group of Ministers report that followed, for example, recommended a slew of reforms. The changes most readily implemented were those that created new commands, agencies and task forces, essentially linear expansion backed by new budgetary allocations. The changes least likely to occur were those required changes in the hierarchy. The most common example of tough reform is the long-standing recommendation for a chief of defense staff. A military chief, as opposed to the service chiefs, could be a solution to the problem that causes the three services not to reconcile their pr Gas Sensing Properties of Te Thin Films: Thickness and UV Gas Sensing Properties of Te Thin Films: Thickness and UV Thickness and UV irradiation effects on the gas sensing properties of Te thin films Abstract In this research, tellurium thin films were investigated for use as hydrogen sulfide gas sensors. To this end, a tellurium thin film has been deposited on Al2o3  substrates by thermal evaporation, and the influence of thickness on the sensitivity of the tellurium thin film for measuring H2S gas is studied. X-ray diffraction (XRD) analysis, scanning electron microscope(SEM) and Raman Spectrometer were utilized for characterizing the prepared samples. XRD patterns indicate that as the thickness increases, the crystallization improves. Observing the images obtained by SEM,  it  is  seen  that the grain size increases as the thickness increases, and consequently, fewer defects will be seen in the surface of the film. Studying the effect of thickness on H2S gas measurement, it became obvious that as the thickness increases, the sensitivity decreases and the response and recovery time increases. Studying the thermal influence of the thin film while measuring H2S gas,  it become s obvious  that as the detection temperature of the thin film increases, sensitivity and the response and recovery times reduce. To improve the response and recovery time of the tellurium thin film for measuring H2S gas, the influence of UV radiation while measuring H2S gas was also investigated. The results indicate that the response and recovery times strongly decrease  using UV radiation. Introduction Tellurium is a P type semiconductor with narrow band gap and a gap energy of 0.35eV which makes it ideal for use in thin film transistors [1], gas sensors [2-4], optical information storage [5] and shields in passive radiative cooling [6]. Recently, it has been shown that the tellurium thin film is sensitive to some toxic gases like H2S [7]. Hydrogen sulfide is a toxic and corrosive gas which is formed in coal mines, oil and gas industries, chemical products plants, and the sewers. Exposure to small amounts of this gas (less 50 ppm) causes headache, poor memory, loss of appetite and irritability, while exposure to large amounts (most of 500 ppm) will cause death after 30-60 minutes [8]. So far, various semiconductor metal oxides have been  produced  for detecting H2S gas such as SnO2, WO3, and CeO2  [9-11]. The main problem of these sensors is that they  require high temperature for measuring H2S gas, and this high temperature will shorten the life of the sensor[12]. Measurin g gas through semiconductor metal oxide depends upon parameters like thickness of the thin film, deposition temperature, and the substrate  material. So far, few reports have been issued about the sensitivity of the tellurium thin film to some reducing and oxidizing gases such as NO2, CO, NH3, and H2S [4,7,13,14]. In this research, the influence of the thickness of the tellurium thin film on detecting H2S gas and also the influence of the film temperature and UV radiation while measuring H2S gas have been studied. Experiment details Tellurium thin films with thicknesses of 100, 200, and 300 nm measured by Quartz digital thickness gauge, were deposited on Al2O3  substrate by thermal evaporation of pure tellurium in a tungsten crucible. Substrates were cleaned for 30 minutes by alcohol and acetone in ultrasonic bath. The initial pressure of the vacuum chamber and the temperature of substrate while depositing were respectively 3Ãâ€"10-5  mbar and 373K. The growth rate of the film and the deposition area were respectively 5nm/s and 100mm2. Gold electrodes were deposited on the surface of film through thermal evaporation and copper wires were attached to them by silver paste. The microstructure of the films was characterized through X-ray diffraction (XRD). The morphology of the films surface was determined by scanning electron microscope (SEM). Sensor response to various concentration of H2S gas was studied in a container made of stainless steel with a volume of 250cm3  .The electrical resistance of the senso rs was measured by a multimeter as a function of time. Gas limit  detection was performed for the films with different thicknesses and at different environment temperatures. The sensors were also exposed to UV radiation while detecting H2S gas. The mechanism of gas detection was investigated by Raman spectroscopy technique. The spectra were recorded before and after exposure to the gas. Raman spectra of the films were recorded in back scattering geometry with a spectral resolution of 3 cm-1. The 785 nm line of Ar+  laser was used  for excitation. Results and Discussion XRD patterns of tellurium films with different thicknesses are shown in fig. 1. In this figure, the peaks  denoted  with star are related to Al2O3  substrate. At 100 nm,  Te thickness peak of low intensity is observed at 27.77 °Ã‚  which is related to Te (101) with hexagonal structure. At 200 nm, in addition to Te (101), another peak corresponding to Te (100) appears at 23.15 °. Finally, besides Te (100) and Te (101), a new peak is observed at 40.78 °which is related to Te (110) with hexagonal structure. From the XRD results, it can be inferred that, thickness increases  the  results in an increase of film crystallinity due to the increase of the number of planes that generate diffraction. Fig. 2 shows the SEM images of prepared Te films at different  thicknesses.  [S1]At 100 nm, the grains are separated from each other  by a  large distance, thereby forming discontinuous and rough surface. Increasing film thickness leads to an increase of surface homogeneit y and continuity, grain size increase  as well. Fig. 3 depicts the resistance variation of the tellurium thin films with different thicknesses at room temperature before exposure to H2S gas. It can be seen that the film resistance decrease with thickness increase due to reduction of irregularity in grain arrangement and inhomogeneity on  the  film surface,  which leads to a better charge carrier mobility. The sensitivity of the films to H2S is given by: S=   Where Ra  and Rg  are the electrical resistance of the film in the air and the H2S respectively. Fig. 4 shows the effect of Te film thickness on sensitivity to 8ppm of H2S at room temperature.  Note that the film sensitivity decreases  with  an increase in  thickness. To explain this behavior, it is worth mentioning that the proposed mechanism for H2S gas measurement is as follows: the oxygen in the air is adsorbed by the film surface, especially in the grain boundaries and film porosities. After adsorption, oxygen reacts with Te film surface and based on the film temperature, it can be ionized into O2, O2-, O  (in the temperatures less than 150CËÅ ¡ the ionization form is O2). These forms of oxygen ionization increase the film hole density which means  a reduction of Ra  in P type semiconductor such as Te. As H2S gas is added, it reacts with ionized oxygen  and the result will be  the  return of electrons inside the film and reduction of the hole numbers and increase of Rg  resistance. The reactions are shown below: O2(gas) O2(ads)(1) O2(ads)+ e O2(ads)(2) H2S(gas)+O2(ads) H2(gas)+SO2(gas)+ e(3) At 100 nm Te thickness, the presence of a high density of grain boundaries and defects results in a high H2S gas adsorption which causes noticeable variations in film electrical resistance,  indicating an increase of sensitivity. At higher thickness, where the grain boundary and defects densities decrease,  the changes in resistance are intangible involving a decrease in the sensitivity as shown in fig. 4. The other important characteristic of sensor is its selectivity. The sensitivity on exposure to 10 ppm of CO, NH3  and NO was found to be 3 %,40 % and -67 % (negative sign indicates reduction in resistance), respectively[]. Thus we see that the Te films have much larger sensitivity towards H2S gas in comparison to other gases. Fig. 5 shows the response kinetics of Te films at different thickness (100 nm and 200 nm) after exposure to 8ppm H2S. Considering the response and recovery times, the times for reaching 90% of steady-state values of Ra  and Rg  respectively  can b e defined. It can be clearly seen in fig. 5 that thickness increase leads to an increase of response and recovery times. The former and the latter are due to high adsorption rate of H2S and O2  gases, respectively, at 100 nm by the great numbers of grain boundaries and defects [15]. Fig. 6 shows Raman spectra of 100 nm Te sample before and after exposure to 8 ppm H2S gas at room temperature. In both spectra, peaks at 123, 143 and 267 cm-1  are related to tellurium. Two other peaks  observed in sample before inducing H2S gas  at 680 and 811 cm-1  are assigned to TeO2  [16].  Notice that the intensity of oxide phase is much less than that of Te phase indicating that a low fraction of Te film is oxidized,  which  is  due to Te atoms on the surface [17]. After exposure to H2S gas,  based on  the proposed  reaction mechanism  the TeO2  peaks have almost disappeared. In addition, no peak corresponding to H2S or compounds of sulfur or hydrogen is detected in f ilm after exposure to H2S gas. Fig. 7 shows the sensors sensitivity as a function of H2S gas concentration for 100, 200 and 300 nm samples at room temperature. The film to 100 nm Te thickness presents a linear response from  the  8 to 34 ppm range and the film sensitivity seems to saturate at higher concentration. As expected, from fig. 7  it can be seen  that the sensitivity decreases as the film thickness is increased. Figure 8 shows the results related to response and recovery time for all samples  while being exposed to various concentrations  of H2S gas  at  room temperature. Studying the results  it is  clear  that as the H2S gas concentration increases, the response time decreases and the recovery time increases.  This  is because as H2S gas concentration increases, the probability of a reaction between gas and ionized oxygen becomes more probable, and more reactions  will be observed  in a shorter time which causes the resistance to change faste r and finally reach a constant level. As the concentration goes up, more H2S gas molecules are absorbed and their desorption requires a longer time. The resistance of different samples as a function of detection temperature before exposure to H2S gas  is shown in fig. 9. In all thickness, a decrease of resistivity is observed with temperature increase due to electrical properties of semiconductor, as well as increase of oxidation reaction rate. In the case  of  300 nm Te films the variation of resistance is insignificant because of  the  very low resistance of this sample. Fig.  10 shows the results related to sensitivity as a function of temperature while being exposed to 8ppm of H2S gas. Investigating the results,  it is found that temperature rise leads to reductions in  sensitivity in all samples, because the number of charge carriers in samples increases as  the  temperature rises and as a result, when samples are exposed to H2S gas, no tangible resistance c hange is observed and sensitivity decreases [18]. In samples with 300nm thickness and with temperatures above 90C °Ã‚  there is no sensitivity against H2S gas,  since the number of charge carriers is so  high  that their change is never tangible by reaction with H2S gas. Fig. 11 shows the recovery and response times as a function of temperature while being exposed  to  8 ppm H2S gas. In all samples,  as the temperature rises the response and recovery time decreases. Overall, two factors are effective for a reaction: first, the molecules which are going to take part in the reaction must have a lot of energy, second, they must collide with one another in an appropriate direction. Temperature rise causes an increase in energy and more effective collisions will take place between reactants, and the response and recovery time decrease. To study the effect of UV irradiation on the sensor properties during the gas detection, samples are simultaneously exposed to 8 ppm H2S gas and UV radiation  at  room temperature. Fig. 12 shows a comparison between the sensor sensitivity of the UV exposed  and unexposed cases as a function of Te film thickness. It is obvious that application of UV radiation results in a dramatic reduction of sensors sensitivity. As it is well-know, UV radiation creates supplementary charge carriers by an excess of electron-hole pairs formation.  Increase of charge carriers number  involves a decrease of resistance such that the changes of resistance  are  not tangible while reacting with H2S gas. Fig. 13 presents the recovery and response times as a function of H2S gas concentration before and after exposure to UV radiation.  It is observed  that the recovery and response times strongly depend on UV radiation. These two parameters decrease with UV radiation due to creation of electron-hole pairs. The created electrons react with adsorbed oxygen, so the number of ionized oxygen reacting with H2S gas increase, which can result in an increase of reaction rate between oxygen and H2S gas. The above explanations can be summarized in the following reactions: O2(gas) O2(ads)(4) O2(ads) + e O2(ads)(5) hÃŽ ½ e + h O2  (ads)+ e 2O(ads)(6) H2S(gas) + O  (ads) H2(gas) + SO(gas) +e(7) It is worth  noting that the increase of UV radiation intensity has no effect on sensitivity,  response and recovery times of Te sensors. Also, to evaluate sensor stability, the samples of 100 nm and 200 nm Te film  were  subjected to 8 ppm H2S at room temperature  for 60 days, then  their basic resistance and sensitivity were measured as shown in fig. 14. The results indicate that both resistance and sensitivity of sensors remain  nearly  constant, confirming suitability of Te films for use as sensor. Conclusion In this work, thickness effect of Te films for H2S gas sensing are investigated. A strong dependence  on  electrical resistance and sensitivity to Te film thickness is observed.  This  means that increasing the thickness leads to a decrease of sensor sensitivity and increase of response and recovery times.  Considering  the sensing mechanism of Te thin films which is based on the interaction of ionized oxygen with H2S gas, the grain boundaries and the surface roughness could be considered as active sites for trapping the gas molecules. Thickness increase leads to a decrease of these active sites. The results show that although the Te sensor can operate at room temperature, a decrease of response-recovery times can be obtained at higher operating temperatures. Raman spectroscopy shows that adsorbed oxygen on the surface of Te films can be removed after exposure to H2S gas,  leading to changes in the film resistance,  UV radiation,  as well as response-recovery times. The prepared sensors present a stability in sensitivity and resistance for 60 days after exposure to H2S gas which confirms  their ability to  be  used  as H2S gas sensor.  

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