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Adolphsen, Chris

Publications and source records attributed to Adolphsen, Chris.

12 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Design of an Emittance Compensation Superconducting Magnet Package for LCLS-II-HE's SRF Photo-Injector

An SRF photo-injector (low frequency, quarter-wave resonator plus emittance compensation magnet) is planned for LCLS-II-HE as it can provide a higher cathode gradient and better electron beam quality than other types of CW electron guns. The magnet package is located immediately downstream of the SRF cavity, and incorporates a solenoid doublet, bucking coils for reduction of the fringe field, normal/skew quadrupoles and horizontal/vertical dipoles. All the magnets are wound of NbTi wire and operate in liquid helium environment. The solenoid package is located inside the SRF gun cryomodule. Design considerations include space limitations, optimal emittance compensation, the magnetic field limits in the superconducting wire and quench protection. The solenoid coils must provide a peak excitation > 25 kgauss 2 ·cm, a fringe field < 20 gauss at the wall of the SRF cavity, an integrated dipole field < 90 gauss·cm and an integrated quadrupole field < 10 gauss. As a result, a genetic algorithm was used to optimize the solenoid design. Correction dipoles and quadrupoles were designed using coil dominated Walstrom style coils.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2022

The Development of Energy-Recovery Linacs

Energy-recovery linacs (ERLs) have been emphasised by the recent (2020) update of the European Strategy for Particle Physics as one of the most promising technologies for the accelerator base of future high-energy physics. The current paper has been written as a base document to support and specify details of the recently published European roadmap for the development of energy-recovery linacs. The paper summarises the previous achievements on ERLs and the status of the field and its basic technology items. The main possible future contributions and applications of ERLs to particle and nuclear physics as well as industrial developments are presented. The paper includes a vision for the further future, beyond 2030, as well as a comparative data base for the main existing and forthcoming ERL facilities. A series of continuous innovations, such as on intense electron sources or high-quality superconducting cavity technology, will massively contribute to the development of accelerator physics at large. Industrial applications are potentially revolutionary and may carry the development of ERLs much further, establishing another shining example of the impact of particle physics on society and its technical foundation with a special view on sustaining nature.

43 PARTICLE ACCELERATORS↗
DOE OSTI2015

Distribution of Heating from Untrapped HOM Radiation in the LCLS-II Cryomodules

The superconducting cavities in the CW linacs of LCLS-II will operate at 2 K, where cooling is very expensive. One source of heat is presented by the higher order mode (HOM) power deposited by the beam. Due to the very short bunch length, especially in the L3 region, the LCLS-II beam spectrum extends into the terahertz range. Ceramic absorbers, at 70 K between cryomodules, are meant to absorb much of this power. In this report we perform two kinds of calculations to estimate the effectiveness of the absorbers and the fractional power that remains to be removed at 2 K

43 PARTICLE ACCELERATORS↗
DOE OSTI2015

Distribution of Heating from Untrapped HOM Radiation in the LCLS-II Cryomodules

The superconducting cavities in the CW linacs of LCLS-II will operate at 2 K, where cooling is very expensive. One source of heat is presented by the higher order mode (HOM) power deposited by the beam. Due to the very short bunch length, especially in the L3 region, the LCLS-II beam spectrum extends into the terahertz range. Ceramic absorbers, at 70 K between cryomodules, are meant to absorb much of this power. In this report we perform two kinds of calculations to estimate the effectiveness of the absorbers and the fractional power that remains to be removed at 2 K.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2014

Untrapped HOM Radiation Absorption in the LCLS-II Cryomodules

The superconducting cavities in the continuous wave (CW) linacs of LCLS-II are designed to operate at 2 K, where cooling costs are very expensive. One source of heat is presented by the higher order mode (HOM) power deposited by the beam. Due to the very short bunch length-especially in L3 the final linac-the LCLS-II beam spectrum extends into the terahertz range. Ceramic absorbers, at 70 K and located between cryomodules, are meant to absorb much of this power. In this report we perform two kinds of calculations to estimate the effectiveness of the absorbers and the amount of beam power that needs to be removed at 2 K.

43 PARTICLE ACCELERATORS↗
DOE OSTI2013

The International Linear Collider Technical Design Report - Volume 3.II: Accelerator Baseline Design

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carried out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.

43 PARTICLE ACCELERATORS↗
DOE OSTI2013

The International Linear Collider Technical Design Report - Volume 3.I: Accelerator R&D in the Technical Design Phase

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carried out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.

43 PARTICLE ACCELERATORS↗