BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
Two SRF photoemission electron guns are under development at BNL. The first gun operates at 704 MHz and is design to deliver high bunch charge and high average current beams for the R&D ERL accelerator. Its cavity is of an elliptical geometry. The gun cryomodule has been commission without a cathode up to the design voltage of 2 MV. The experiments with a copper cathode are underway. The second gun utilizes a quarter wave resonator geometry with coaxial cathode insert and beam tube RF power coupler. It will be used to produce high bunch charges, but low average beam currents for the coherent electron cooling proof-of-principle experiment. This 112 MHz SRF gun was first tested two years ago. Since then it was rebuilt in a new cryomodule and cryogenically re-tested in late 2012/early 2013, reaching the accelerating gap voltage of 0.9 MV. This paper describes main design features of two SRF guns, presents test results and discusses future plans.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
Niowave, Inc., Lansing, Michigan, USA
SBU, Stony Brook, New York, USA
A short 22-MeV linac under development at BNL will provide high charge, low repetition rate beam for the coherent electron cooling demonstration experiment in RHIC. The linac will include a 112 MHz SRF gun and a 704 MHz five-cell accelerating SRF cavity. The paper describes the two SRF systems, discusses the project status, first test results and schedule.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
ANL, Argonne, USA
A search for the QCD Critical Point has renewed interest to electron cooling ion beams in RHIC at energies below 10 GeV/nucleon. The electron cooling will utilize bunched electron beams form an SRF linac at energies from 0.9 to 5 MeV. The SRF linac will consist of two quarter wave structures: a photoemission electron gun and a booster cavity. In this paper we present preliminary design consideration of this SRF linac.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
The 704 MHz superconducting RF gun for the R&D ERL project is under comissioning at BNL. Since last November, the SRF gun has been conditioned and demonstrated an operational accelerating voltage of 2 MV (an accelerating gradient of 23.5 MV/m). Preparations for the cathode insertion are in final stages and we expect the gun to generate the first electron beam this summer. This paper discusses the BNL SRF gun system,and the results of the SRF gun commissioning.
MOP028
Stony Brook University, Stony Brook, USA
BNL, Upton, Long Island, New York, USA
A theoretical model based on network analysis is proposed here to study the external quality factor (Qext) of a dual-feed coupling for superconducting radio-frequency (SRF) cavities. The calculation results from the model shows that the external Q factor of a dual-feed coupling system changes with the phase difference of the two coupling arms with a period of 360 degrees. If we change the phase of the two arms simultaneously, the external Q factor would change with a period of 180 degrees.
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
BNL, Upton, Long Island, New York, USA
HZDR, Dresden, Germany
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
LBNL, Berkeley, California, USA
Stanford University, Stanford, California, USA
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
DESY, Hamburg, Germany
SLAC, Menlo Park, California, USA
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
A 56 MHz superconducting RF cavity will be the first quarter wave resonator (QWR) installed in a high energy storage ring. It is expected to boost the luminosity of the Relativistic Heavy Ion Collider by more than 60% after installation. In this paper, we discuss the cavity parameters and design features. We report the results from the first vertical test of this cavity at 4 K.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
CERN, Geneva, Switzerland
SLAC, Menlo Park, California, USA
The crab cavity program for LHC luminosity upgrade envisages the testing of at least one of the three competing crab cavities in the Super Proton Synchrotron (SPS) of CERN by 2016. This paper presents the design optimization of a Double Quarter Wave Crab Cavity (DQWCC) prototype suited for testing in SPS.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
A proof of principle Double Quarter Wave Crab Cavity (DQWCC) was designed and fabricated for the Large Hadron Collider (LHC) luminosity upgrade. Vertical cryogenic test has been done in Brookhaven National Lab (BNL). We report the test results of this design.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
CERN, Geneva, Switzerland
A double quarter wave crab cavity was designed for the Large Hadron Collider luminosity upgrade. Starting from the analytical calculation of simplified RLC circuit, a compact higher order mode filter is developed for this cavity. Finite element simulation results are presented. The design concept is generic and can easily be adapted to other cavities.
BNL, Upton, Long Island, New York, USA
HZB, Berlin, Germany
Stony Brook University, Stony Brook, USA
The Brookhaven Energy Recovery Linac (ERL) is operated as R&D setup for high-current, high charge electron beams. It is comprised of a superconducting (SC) five-cell cavity and a half-cell SC photoinjector electron RF gun. Achieving the performance objectives requires effective HOM damping in the linac and gun cavity. Among the HOM dampers being developed is a beam-tube type HOM load for the electron gun consisting of a ceramic break surrounded by ferrite tiles. This design is innovative in its approach and achieves a variety of ends including broadband HOM damping and protection of the superconducting cavity from potential damage of the separately cooled ferrite tiles. The damper properties are described by the coupling impedance to a beam and the external Q to constrain the unloaded mode Q’s. Measured results for the gun damper at room and superconducting temperatures are presented
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
Niowave, Inc., Lansing, Michigan, USA
SBU, Stony Brook, New York, USA
A short 22-MeV linac under development at BNL will provide high charge, low repetition rate beam for the coherent electron cooling demonstration experiment in RHIC. The linac will include a 112 MHz SRF gun and a 704 MHz five-cell accelerating SRF cavity. The paper describes the two SRF systems, discusses the project status, first test results and schedule.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
ANL, Argonne, USA
A search for the QCD Critical Point has renewed interest to electron cooling ion beams in RHIC at energies below 10 GeV/nucleon. The electron cooling will utilize bunched electron beams form an SRF linac at energies from 0.9 to 5 MeV. The SRF linac will consist of two quarter wave structures: a photoemission electron gun and a booster cavity. In this paper we present preliminary design consideration of this SRF linac.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
A 56 MHz superconducting RF cavity will be the first quarter wave resonator (QWR) installed in a high energy storage ring. It is expected to boost the luminosity of the Relativistic Heavy Ion Collider by more than 60% after installation. In this paper, we discuss the cavity parameters and design features. We report the results from the first vertical test of this cavity at 4 K.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
CERN, Geneva, Switzerland
SLAC, Menlo Park, California, USA
The crab cavity program for LHC luminosity upgrade envisages the testing of at least one of the three competing crab cavities in the Super Proton Synchrotron (SPS) of CERN by 2016. This paper presents the design optimization of a Double Quarter Wave Crab Cavity (DQWCC) prototype suited for testing in SPS.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
A proof of principle Double Quarter Wave Crab Cavity (DQWCC) was designed and fabricated for the Large Hadron Collider (LHC) luminosity upgrade. Vertical cryogenic test has been done in Brookhaven National Lab (BNL). We report the test results of this design.
BNL, Upton, Long Island, New York, USA
Stony Brook University, Stony Brook, USA
CERN, Geneva, Switzerland
A double quarter wave crab cavity was designed for the Large Hadron Collider luminosity upgrade. Starting from the analytical calculation of simplified RLC circuit, a compact higher order mode filter is developed for this cavity. Finite element simulation results are presented. The design concept is generic and can easily be adapted to other cavities.