6 September 2012A recent workshop reviewed the latest experiences with the phenomenon of electron clouds at the LHC and other accelerators. Electron clouds – abundantly generated in accelerator vacuum chambers by residual-gas ionization, photoemission and secondary emission – can affect the operation and performance of hadron and lepton accelerators in a variety of ways. They can induce increases in vacuum pressure, beam instabilities, beam losses, emittance growth, reductions in the beam lifetime or additional heat loads on a (cold) chamber wall.
Category: Feature | Tagged: beam emittance, CesrTA, damping ring, electron cloud
Barbara Warmbein | 28 January 2010Not all people who have the same goals use the same means to achieve them — just think of the two proposed electron-positron colliders ILC and CLIC. And not all people who use the same means also pursue the same goals. A workshop held in January at CERN in Geneva brought the two linear colliders and many of the world's light sources and B-factories together to discuss one common problem: how to make your beam as small and intense as possible to either produce more particle collisions or produce more brilliant light for your light source users, or in short: how to design or operate low-emittance rings.
Category: Around the World | Tagged: beam emittance, low emittance, low emittance ring
Barry Barish | 2 October 2008The ILC's beams pass through each accelerating element once before they are directed to collide with the beam travelling in the opposite direction. This poses the two main challenges in the ILC: to achieve a very high gradient in the accelerator in order to make it as short as possible while achieving the desired energy, and to achieve very small beam spots to maximise the probability of collisions by the crossing beams.
Category: Director's Corner | Tagged: ATF2, beam emittance, beam spot size, KEK
Elizabeth Clements | 5 July 2007When the Accelerator Test Facility (ATF) group at KEK decided to upgrade their beam position monitor system in 2005, Marc Ross had a solution. Based at SLAC at the time, he was a longtime collaborator with KEK and familiar with the instrumentation systems used throughout Fermilab’s accelerator complex. In 2006, Ross became the head of Fermilab’s Technical Division and could see how to continue his initiated beam position monitor upgrade efforts at the ATF damping ring. Called Echotek boards, these digital signal processing based systems offer a higher resolution potential – a characteristic that allows physicists to see more details about the beam. As it turned out, Fermilab was willing to make several Echotek boards available for testing the ATF system. Hence a new collaboration was born.
Category: Feature | Tagged: ATF, beam emittance, beam position monitor, Fermilab, KEK, SLAC
Perrine Royole-Degieux | 23 February 2006Obtaining high luminosity beams will be crucial for the future International Linear Collider. An important indication on the beam quality is given by the emittance which depends on its size and opening angle. The lower the emittance, the easier it is to focus the beam and the more particle collisions can occur and be analysed. In the GDE the "Accelerator physics" group, a special team dedicated to the technical systems organised at CERN, on 08-11 February 2006, a "Low Emittance Transport Workshop". About 30 accelerator scientists, coming from all regions, attended it.
Category: Feature | Tagged: beam emittance