<<O>>  Difference Topic ElProyectoILCInternationalLinearCollider (r1.2 - 22 Sep 2009 - Main.iglesias)


0. El detector ILD

 <<O>>  Difference Topic ElProyectoILCInternationalLinearCollider (r1.1 - 18 Sep 2009 - Main.iglesias)
Line: 1 to 1

0. El detector ILD

0.a. El proyecto ILC: International Linear Collider

The International Large Detector (ILD) is a concept for a detector at the International Linear Collider, ILC. The ILC will collide electrons and positrons at energies of initially 500 GeV??, upgradeable to 1 TeV??. The ILC has an ambitious physics program, which will extend and complement that of the Large Hadron Collider (LHC). The ILC physics case has been well documented, most recently (August 2007) in the ILC Reference Design Report, RDR. It provides the first detailed technical snapshot of the proposed future electron-positron collider, defining in detail the technical parameters and components that make up each section of the 31-kilometer long accelerator. The report will guide the development of the worldwide R&D programme, motivate international industrial studies and serve as the basis for the final engineering design needed to make an official project proposal later this decade.

A hallmark of physics at the ILC is precision. The clean initial state and the comparatively benign environment of a lepton collider are ideally suited to high precision measurements. To take full advantage of the physics potential of ILC places great demands on the detector performance.

The project ILC consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 31 kilometres in length, the beams collide 14,000 times every second at extremely high energies—500 billion-electron-volts (GeV?). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV?) machine during the second stage of the project.



  • The Linacs : Scientists will use two main linear accelerators (“linacs”), one for electrons and one for positrons, each 12 kilometers long, to accelerate the bunches of particles toward the collision point. Each linac consists of 8.000 superconducting cavities nestled within a series of cooled vessels to form cryomodules. The modules use liquid helium to cool the cavities to -271°C, only slightly above absolute zero. Scientists will launch traveling electromagnetic waves into the cavities to “push” the particles through, and accelerate them to energies that will total 500 GeV?.

  • Positrons : Positrons, the antimatter partners of electrons, do not exist naturally on earth. To produce them scientists will send the high-energy electron beam through an undulator, a special arrangement of magnets in which electrons are sent on a “roller-coaster” course. This turbulent motion will cause the electrons to emit a stream of photons. Just beyond the undulator the electrons will return to the main acelerator, while the photons will hit a titaniumalloy target and produce pairs of electrons and positrons. The positrons will be collected and launched into their own 250-meter 5-GeV accelerator .

  • The Detectors :Traveling towards each other at nearly the speed of light, the electron and positron bunches will collide with a total energy of 500 GeV?. Scientists will record the spectacular collisions in two giant particle detectors. These work like gigantic cameras, taking napshots of the particles produced by the electron-positron annihilations. The two detectors will incorporate different but complementary state-of-the-art technologies to capture information about every particle produced in each collision. Having these two detectors will allow vital cross-checking of the potentially-subtle physics discovery signatures.

  • The Damping Rings : When created, neither the electron nor the positron bunches are compact enough to yield the high density needed to produce collisions inside the detectors. Scientists will solve this problem by using seven-kilometer-circumference damping rings, one for lectrons and one for positrons. In each ring, the bunches will travel through a series of wigglers that literally “wiggle” the beam to emit photons. This process makes the bunches more compact. Each bunch will circle the damping ring roughly 10.000 times in only two tenths of a second. Upon exiting the damping rings, the bunches will be a few millimeters long and thinner than a human hair.

  • Electrons : To produce electrons scientists will fire high-intensity, two-nanosecond light pulses from a laser at a target and knock out billions of electrons per pulse. They will gather the electrons using electric and magnetic fields to create bunches of particles and launch them into a 250-meter linear accelerator that boosts their energy to 5 GeV?.


-- Main.iglesias - 18 Sep 2009

META FILEATTACHMENT ILC_Dibujo_perfil.jpg attr="" comment="" date="1253267622" path="ILC_Dibujo_perfil.jpg" size="464110" user="iglesias" version="1.1"
META FILEATTACHMENT ILC_Dibujo1.jpg attr="" comment="" date="1253267632" path="ILC_Dibujo1.jpg" size="956718" user="iglesias" version="1.1"
Revision r1.1 - 18 Sep 2009 - 09:56 - Main.iglesias
Revision r1.2 - 22 Sep 2009 - 08:28 - Main.iglesias