San Carlos of Guatemala University Faculty of Engineering Technical Language 1 Section A

The Large Hadron Collider

Student Name:

Ghelber Isaac Ramírez Velásquez

ID:

201232000

INTRODUCTION

This report contains research on the Large Hadrons Collider which is a construction that uses electromagnetic fields to accelerate charged particles to speeds (and therefore energy) very high and may be close to that of light. For these reasons enables a variety of important experiments otherwise could not be realized because of the complexity and accuracy experiments requiring

The Large Hadrons Collider , is of great importance to physics such as the microscope for bacteriological study and analysis is just as important as the analysis of blood in medicine, one way or another a new stage frame with the construction of the large Hadrons Collider, as important theories were confirmed and particles that confirm these theories as the Higgs boson is discovered , which are explained in detail in the research content

Objectives:

General:

Practice and gain knowledge in the English language through research.

• Specific:

Know:

o The functions of the Large Hadron Collider

o The discoveries that have been made in the Large Hadron Collider

o The importance of Large Hadron Collider to the scientific community

The Large Hadron Collider

The Large Hadron Collider (LHC) is the world's largest and most powerful particle collider, built by the European Organization for Nuclear Research (CERN) from 1998 to 2008. Its aim is to allow physicists to test the predictions of different theories of particle physics and high-energy physics, and particularly prove or disprove the existence of the theorized Higgs particle and of the large family of new particles predicted bysupersymmetric theories. The Higgs particle was confirmed by data from the LHC in 2013. The LHC is expected to address some of the unsolved questions of physics, advancing human understanding of physical laws. It contains seven detectors, each designed for specific kinds of research.

The LHC was built in collaboration with over 10,000 scientists and engineers from over 100 countries, as well as hundreds of universities and laboratories. It lies in a tunnel 27 kilometres (17 mi) in circumference, as deep as 175 metres (574 ft) beneath the Franco-Swiss border nearGeneva, Switzerland.

As of 2014, the LHC remains one of the largest and most complex experimental facilities ever built. Its synchrotron is designed to initially collidetwo opposing particle beams of either protons at up to 7 teraelectronvolts (7 TeV or 1.12 microjoules) per nucleon, or lead nuclei at an energy of 574 TeV (92.0 µJ) per nucleus (2.76 TeV per nucleon-pair), with energies to be doubled to around 14 TeV collision energy - more than seven times any predecessor collider - by around 2015. Collision data was also anticipated to be produced at an unprecedented rate of tens of petabytesper year, to be analysed by a grid-based computer network infrastructure connecting 140 computing centers in 35 countries (by 2012 the LHC Computing Grid was the world's largest computing grid, comprising over 170 computing facilities in a worldwide network across 36 countries).

The LHC went live on 10 September 2008, with proton beams successfully circulated in the main ring of the LHC for the first time, but 9 days later a faulty electrical connection led to the rupture of a liquid helium enclosure, causing both a magnet quench and several tons of helium gas escaping with explosive force. The incident resulted in damage to over 50 superconducting magnets and their mountings, and contamination of thevacuum pipe, and delayed further operations by 14 months. On November 20, 2009 proton beams were successfully circulated again, with the first recorded proton–proton collisions occurring 3 days later at the injection energy of 450 GeV per beam. On March 30, 2010, the first collisions took place between two 3.5 TeV beams, setting a world record for the highest-energy man-made particle collisions, and the LHC began its planned research program.

By November 2012, the LHC had discovered two previously unobserved particles (the χb (3P)) bottomonium state and a massive 125 GeV boson (which subsequent results confirmed to be the long-sought Higgs boson), created a quark–gluon plasma, and recorded the first observations of the very rare decay of the Bs meson into two muons (Bs

0 → μ+μ-) (a major test of supersymmetry).

The LHC operated at 3.5 TeV per beam in 2010 and 2011 and at 4 TeV in 2012. It operated for two months in 2013 colliding protons with lead nuclei, and went into shutdown for

upgrades to increase beam energy to 6.5 TeV per beam, with reopening planned for early 2015.

Purpose:

Physicists hope that the LHC will help answer some of the fundamental open questions in physics, concerning the basic laws governing the interactions and forces among the elementary objects, the deep structure of space and time, and in particular the interrelation between quantum mechanics and general relativity, where current theories and knowledge are unclear or break down altogether. Data are also needed from high energy particle experiments to suggest which versions of current scientific models are more likely to be correct – in particular to choose between theStandard Model and Higgsless models and to validate their predictions and allow further theoretical development. Many theorists expect new physics beyond the Standard Model to emerge at the TeV energy level, as the Standard Model appears to be unsatisfactory. Issues possibly to be explored by LHC collisions include:

Are the masses of elementary particles actually generated by the Higgs mechanism via electroweak symmetry breaking? It is expected that the collider will either demonstrate or rule out the existence of the elusive Higgs boson, thereby allowing physicists to consider whether the Standard Model or its Higgsless alternatives are more likely to be correct.

Is supersymmetry, an extension of the Standard Model and Poincaré symmetry, realised in nature, implying that all known particles havesupersymmetric partners?

Are there extra dimensions, as predicted by various models based on string theory, and can we detect them?

What is the nature of the dark matter that appears to account for 27% of the mass-energy of the universe?

Other open questions that may be explored using high energy particle collisions:

It is already known that electromagnetism and the weak nuclear force are different manifestations of a single force called the electroweak force. The LHC may clarify whether the electroweak force and the strong nuclear force are similarly just different manifestations of one universal unified force, as predicted by various Grand Unification Theories.

Why is the fourth fundamental force (gravity) so many orders of magnitude weaker than the other three fundamental forces? See also Hierarchy problem.

Are there additional sources of quark flavour mixing, beyond those already predicted within the Standard Model?

Why are there apparent violations of the symmetry between matter and antimatter? See also CP violation.

What are the nature and properties of quark–gluon plasma, believed to have existed in the early universe and in certain compact and strange astronomical objects today? This will be investigated by heavy ion collisions in ALICE.

Findings:

CERN scientists estimated that, if the Standard Model is correct, a single Higgs boson would be produced every few hours, and that over a few years enough data to confirm or disprove the Higgs boson unambiguously and to obtain sufficient results concerning supersymmetric particles would be gathered to draw meaningful conclusions. Some extensions of the Standard Model predict additional particles, such as the heavy W' and Z' gauge bosons, which may also lie within reach of the LHC to discover.

The first physics results from the LHC, involving 284 collisions which took place in the ALICE detector, were reported on 15 December 2009. The results of the first proton–proton collisions at energies higher than Fermilab's Tevatron proton–antiproton collisions were published by the CMS collaboration in early February 2010, yielding greater-than-predicted charged-hadronproduction.

After the first year of data collection, the LHC experimental collaborations started to release their preliminary results concerning searches for new physics beyond the Standard Model in proton-proton collisions. No evidence of new particles was detected in the 2010 data. As a result, bounds were set on the allowed parameter space of various extensions of the Standard Model, such as models with large extra dimensions, constrained versions of the Minimal Supersymmetric Standard Model, and others.

On 24 May 2011, it was reported that quark–gluon plasma (the densest matter besides black holes) has been created in the LHC.

Between July and August 2011, results of searches for the Higgs boson and for exotic particles, based on the data collected during the first half of the 2011 run, were presented in conferences in Grenoble and Mumbai. In the latter conference it was reported that, despite hints of a Higgs signal in earlier data, ATLAS and CMS exclude with 95% confidence level (using the CLsmethod) the existence of a Higgs boson with the properties predicted by the Standard Model over most of the mass region between 145 and 466 GeV. The searches for new particles did not yield signals either, allowing to further constrain the parameter space of various extensions of the Standard Model, including its supersymmetric extensions.

On 13 December 2011, CERN reported that the Standard Model Higgs boson, if it exists, is most likely to have a mass constrained to the range 115–130 GeV. Both the CMS and ATLAS detectors have also shown intensity peaks in the 124–125 GeV range, consistent with either background noise or the observation of the Higgs boson.

On 22 December 2011, it was reported that a new particle had been observed, the χb (3P) bottomonium state.

On 4 July 2012, both the CMS and ATLAS teams announced the discovery of a boson in the mass region around 125–126 GeV, with a statistical significance at the level of 5 sigma. This meets the formal level required to announce a new particle which is consistent with the Higgs boson, but scientists are cautious as to whether it is formally identified as actually being the Higgs boson, pending further analysis.

On 8 November 2012, the LHCb team reported on an experiment seen as a "golden" test of supersymmetry theories in physics, by measuring the very rare decay of the Bs meson into twomuons (Bs

0 → μ+μ−). The results, which match those predicted by the non-supersymmetrical Standard Model rather than the predictions of many branches of supersymmetry, show the decays are less common than some forms of supersymmetry predict, though could still match the predictions of other versions of supersymmetry theory. The results as initially drafted are stated to be short of proof but at a relatively high 3.5 sigma level of significance.

In August 2013 the team revealed an anomaly in the angular distribution of B meson decay products which could not be predicted by the Standard Model; this anomaly had a statistical certainty of 4.5 sigma, just short of the 5 sigma needed to be officially recognized as a discovery. It is unknown what the cause of this anomaly would be, although the Z' boson has been suggested as a possible candidate.

Conclusions

1. The Large Hadron Collider is the world’s largest and most powerful particle accelerator.

2. The Large Hadron Collider consists of a 27-kilometre ring of superconducting magnets with a number of accelerating structures to boost the energy of the particles along the way.

3. All the controls for the Large hadron collider, its services and technical infrastructure are housed under one roof at the CERN Control Centre

4. The Large Hadron Collider confirmed the existence of the particle known as the Higgs boson July 4, 2012, sometimes called "particle mass"

5. The large hadron collider provides scientific data to further the understanding of the origin and formation of the Universe

Bibliographic References

Large Hadron Collider; WIKIPEDIA, http://en.wikipedia.org/wiki/Large_Hadron_Collider [Viewed Online: 27/03/2014]