Optimization of Undulator Parameters for 125 GeV Drive Beam

In the baseline design of the International Linear Collider (ILC) an undulator-based source is foreseen for the positron source in order to match the physics requirements. The baseline parameters are optimized for the ILC at sqrt(s)=500 GeV, that means an electron drive beam of 250 GeV. Precision measurements in the Higgs sector, however, require measurements at sqrt(s)=250 GeV, i.e. running with the electron drive beam only at 125 GeV, which imposes a challenge for achieving a high yield. Therefore the baseline undulator parameters have to be optimized as much as possible within their technical performances. In this bachelor thesis we therefore present a theoretical study on the radiation spectra of a helical undulator, based on the equation for the radiated synchrotron energy spectral density per solid angle per electron in the relativistic, far-field and point-like charge approximation. From this starting point the following undulator properties are examined: the deposited power in the undulator vessel, which can disrupt the functionality of the undulator magnets, the protective property of a mask on this disturbances and the number of positrons produced by the synchrotron radiation in a Ti6Al4V target. Those quantities were evaluated for various values for parameters as undulator period, undulator length and magnetic flux in order to find optimal baseline parameter sets for sqrt(s)=250 GeV.Comment: 15 pages, Talk presented at the International Workshop on Future Linear Colliders (LCWS2018), Arlington, Texas, 22-26 October 201

Plasma Lenses: Possible alternative OMD at the ILC

In the baseline design of the International Linear Collider (ILC) an undulator-based source is foreseen for the positron source in order to match the physics requirements. The recently chosen first energy stage with sqrt(s)=250 GeV requires high luminosity and imposes an effort for all positron source designs at high-energy colliders. In this paper we perform a simulation study and adopt the new technology of plasma lenses to capture the positrons generated by the undulator photons and to create the required high luminosity positron beam.Comment: Talk presented at the International Workshop on Future Linear Colliders (LCWS2019), Sendai, Japan, 28 October-1 November 201

Plasma Lens Prototype Progress: Plasma Diagnostics And Particle Tracking For ILC e+ Source

In recent years, the concept of high-gradient, symmetric focusing using active plasma lenses has regained notable attention owing to its potential benefits in terms of compactness and beam dynamics when juxtaposed with traditional focusing elements. An enticing application lies in the optical matching of extensively divergent positrons originating from the undulator-based ILC positron source, thereby enhancing the positron yield in subsequent accelerating structures. Through a collaboration between the University of Hamburg and DESY Hamburg, a scaled-down prototype for this purpose has been conceptualized and fabricated. In this presentation, we provide an overview of the ongoing progress in the development of this prototype. Furthermore, first insights into the development of a particle tracking code especially designed for plasma lenses with implemented Bayes optimization, are given.Comment: TALK PRESENTED AT THE INTERNATIONAL WORKSHOP ON FUTURE LINEAR COLLIDERS (LCWS2023), 15-19 MAY 2023. C23-05-15.3., LCWS23, SLAC, Plasma lens, ILC, 3 page

Optimization of Undulator Parameters for 125 GeV Drive Beam

In the baseline design of the International Linear Collider (ILC) an undulator-based source is foreseen for the positron source in order to match the physics requirements. The baseline parameters are optimized for the ILC at $\sqrt{s} =$ 500 GeV, that means an electron drive beam of 250 GeV. Precision measurements in the Higgs sector, however, require measurements at $\sqrt{s} =$ 250 GeV, i.e. running with the electron drive beam only at 125 GeV, which imposes a challenge for achieving a high yield. Therefore the baseline undulator parameters have to be optimized as much as possible within their technical performances. In this bachelor thesis we therefore present a theoretical study on the radiation spectra of a helical undulator, based on the equation for the radiated synchrotron energy spectral density per solid angle per electron in the relativistic, far-field and point-like charge approximation. From this starting point the following undulator properties are examined: the deposited power in the undulator vessel, which can disrupt the functionality of the undulator magnets, the protective property of a mask on this disturbances and the number of positrons produced by the synchrotron radiation in a Ti-6Al-4-V target. Those quantities were evaluated for various values for parameters as undulator period, undulator length and magnetic flux in order to find optimal baseline parameter sets for $\sqrt{s} =$ 250 GeV

Preparation of a Prototype Plasma Lens as an Optical Matching Device for the ILC e⁺ Source

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. A collaboration between University Hamburg and DESY Hamburg has been established to develop a prototype design for this application. Here, we discuss beam dynamics simulation results, preliminary parameters of the lens prototype, and the current status of the prototype design

Plasma Lens Prototype Progress: Plasma Diagnostics And Particle Tracking For ILC e+e^+ Source

In recent years, the concept of high-gradient, symmetric focusing using active plasma lenses has regained notable attention owing to its potential benefits in terms of compactness and beam dynamics when juxtaposed with traditional focusing elements. An enticing application lies in the optical matching of extensively divergent positrons originating from the undulator-based ILC positron source, thereby enhancing the positron yield in subsequent accelerating structures. Through a collaboration between the University of Hamburg and DESY Hamburg, a scaled-down prototype for this purpose has been conceptualized and fabricated. In this presentation, we provide an overview of the ongoing progress in the development of this prototype. Furthermore, first insights into the development of a particle tracking code especially designed for plasma lenses with implemented Bayes optimization, are given

Status of plasma diagnostics on the prototype plasma lens for optical matching at the ILC e+e^+ source

In recent years, high-gradient, symmetric focusing with active plasma lenses has regained significant interest due to its potential advantages in compactness and beam dynamics compared to conventional focusing elements. A promising application could be optical matching of highly divergent positrons from the undulator-based ILC positron source into the downstream accelerating structures to increase the positron yield.In a collaboration between University Hamburg and DESY Hamburg a downscaled prototype for this application has been developed and constructed. Here, we present the current status of the prototype development

Plasma Lenses: Possible alternative OMD at the ILC

In the baseline design of the International Linear Collider (ILC) an undulator-based source is foreseen for the positron source in order to match the physics requirements. The recently chosen first energy stage with sqrt(s)=250 GeV requires high luminosity and imposes an effort for all positron source designs at high-energy colliders. In this paper we perform a simulation study and adopt the new technology of plasma lenses to capture the positrons generated by the undulator photons and to create the required high luminosity positron beam