Conveners
Accelerator: Particle Sources
- Joe Grames (Jefferson Lab)
- Andriy Ushakov (Jefferson Lab)
- Gudrid Moortgat-Pick
- Steffen Doebert (CERN)
- MASAO KURIKI (Hiroshima University)
- Spencer Gessner (SLAC)
Accelerator: Particle Sources
- Spencer Gessner (SLAC)
- Gudrid Moortgat-Pick
- MASAO KURIKI (Hiroshima University)
- Steffen Doebert (CERN)
- Joe Grames (Jefferson Lab)
- Andriy Ushakov (Jefferson Lab)
Accelerator: Particle Sources
- Spencer Gessner (SLAC)
- MASAO KURIKI (Hiroshima University)
- Andriy Ushakov (Jefferson Lab)
- Gudrid Moortgat-Pick
- Joe Grames (Jefferson Lab)
- Steffen Doebert (CERN)
Superlattice-strained negative electron affinity GaAs photocathodes can produce electron beam polarization in excess of 90%, and if appropriately layered, quantum efficiencies of multiple percent. As such is the go-to source for polarized photoinjector applications and is the planned source for multiple future collider designs. However, it achieves negative electron affinity by virtue of a...
During the ILC Global Design Effort (2007) two 200 kV high voltage photoguns based on an inverted insulator geometry were developed in 2010 and successfully tested at Jefferson Lab (JLab). One of the photoguns has been operated at 130 kV in the CEBAF accelerator for the JLab nuclear physics program. The inverted insulator replaces the electrode support structure, consequently significantly...
The undulator-based positron source offers even polarized longitudinally as well as transversely polarized beams.
Both cases are very substantial for matching the promised physics and precision goals.
An overview will be given about the baseline undulator source set-up and technical open issues will be addressed.
Recent progress on the field simulations, the rotating wheel design, the...
The performance of positron source in the International Linear Collider (ILC) is critical for the luminosity and therefore the physics output of this planned, future high energy physics machine. In the undulator-based source proposed for the ILC, positrons are produced by generation of electron-positron pairs by an incident high energy photon on a high-Z target material. The amount of positron...
The progress in the development of a polarized positron injector for the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Laboratory is presented. The polarized positron beam is generated by a high current polarized electron beam (>1 mA @ 120 MeV) via bremsstrahlung radiation and e+e- pair production in the tungsten target. The simulations show that using an optimized target...
This contribution describes optimized layouts of a positron injector anticipated for generating polarized and unpolarized positron beams for the CEBAF accelerator at the Thomas Jefferson National Accelerator Facility (JLab). This injector should provide polarized beams (>60%) with intensity >50 nA, or higher intensity “unpolarized” beam with intensity >3 uA.
The layouts of the positron...
Status of E-driven positron source for ILC including R&D plan is presented. A test stand to operate a proto-type Flux concentrator will be constructed in the STF facility. The status of Flux concentrator design and the test stand will be presented.
A water-cooled target with a rotation rod is designed for the E-Driven positron source. The test operation of the rotating rod examining the vacuum performance of the ferr-fluid seal is ongoing. The status and a new design improving the performance will be presented.
Start to end simluation of ILC E-Driven Positron source is presented.
APS cavity is designed for the capture linac of E-Driven positron source. In addition to the RF load, a large heat load by the beam is expected. The experiment to simulating the detuning is being carried out at Iwate ILC lab. The status will be reported.
Beam loading compensation in the booster linac by traveling wave linac is disscussed.
Positron targets are a critical component of future Linear Colliders. Traditional targets are composed of high-Z metals that become brittle over time due to constant bombardment by high-power electron beams. We explore the possibility of a liquid xenon target which is continuously refreshed and therefore not susceptible to the damage mechanisms of traditional solid targets. Using the GEANT4...
As part of the Snowmass process, a number of recommendations were made for research topics that can improve the performance and target capabilities of high-power target and sources for HEP applications. The DOE has commissioned a Roadmap for this research, with the Roadmap Workshop held on April 11-12. This talk will summarize the results of the workshop and present the Roadmap.
The high-intensity, polarized electron source is a critical component for the electron-ion collider, requiring a polarized electron gun with higher voltage and higher bunch charge than any existing polarized electron source. At Brookhaven National Laboratory, we have built and successfully conditioned an inverted HVDC photoemission gun up to 350 kV. In this study, we report on the performance...
For the planned International Linear Collider (ILC) a material for the positron source target is required which can withstand the high energy deposition needed for a high luminosity positron source. To distribute the load and keep the target at a reasonable temperature, the target is rotated with high velocity. Therefore, the material needs not only withstand the cyclical thermal load but also...
The adiabatic matching device is a critical component of any positron source for capturing the particles and has been as well a limitation of existing sources. CERN studies adiabatic matching devices for CLIC and FCCee. Magnetic design studies have been done to optimise the shape of these pulsed magnets in order to maximise the field and improve their robustness against field breakdowns....
The International Linear Collider is a planned electron-positron linear collider with its positron
source producing positrons by aiming undulator radiation onto a rotating target. The resulting,
highly divergent positron beam requires immediate optical matching to improve the luminosity and
therefore the success of the intended collision experiments. Here, optical matching refers to the...
In recent years, high-gradient, symmetric focusing with active plasma lenses has regained significant interest due to
the potential advantages in compactness and beam dynamics compared to conventional focusing elements.
One potential application is the optical matching of highly divergent positrons from the undulator-based ILC positron source into
the downstream accelerating structures. In...
We investigate electrostatic traps as a novel source of positron beams for accelerator physics applications. Penning-Malmberg (PM) traps are commonly employed in low-energy antimatter experiments. Positrons contained in the trap are cooled to room temperature or below. We calculate the thermal emittance of the positrons in the trap and show that it is comparable to or better than the...
Detailed simulations of the helical undulator with both ideal and realistic parameters have been performed in detail. The power deposited in walls due to secondary particles, which are produced when a photon passes through the mask material, are included. A possible mask design with a high photon absorption efficiency has been studied for three different materials.
The photon masks must be...
