Engineering Papers⌕ Search

Engineering topics

Solyak, N

Publications and source records attributed to Solyak, N.

13 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Multi-harmonic RF test stand for RF breakdown studies

A multi-harmonic RF test stand is under construction at Yale Beam Physics Laboratory. It includes a frequency multiplier which can generate high power harmonics efficiently that are phase locked to the fundamental drive frequency. In a bi-modal asymmetric cavity powered by this RF source, the cavity may experience reduced exposure time to peak fields and sweeping of peak fields across their surfaces, and strong asymmetry between surfaces that may experience cathode-and anode-like fields; these phenomena are to be assessed for their influence on RF breakdown probabilities.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

Design Considerations for an MEBT Chopper Absorber of 2.1 MeV H- at the Project X Injector Experiment at Fermilab

The Project X Injector Experiment (PIXIE) will be a prototype of the Project X front end that will be used to validate the design concept and decrease technical risks. One of the most challenging components of PIXIE is the wide-band chopping system of the Medium Energy Beam Transport (MEBT) section, which will form an arbitrary bunch pattern from the initially CW 162.5 MHz 5mA beam. The present scenario assumes diverting 80% of the beam to an absorber to provide a beam with the average current of 1mA to SRF linac. This absorber must withstand a high level of energy deposition and high ion fluence, while being positioned in proximity of the superconductive cavities. This paper discusses design considerations for the absorber. Thermal and mechanical analyses of a conceptual design are presented, and future plans for the fabrication and testing of a prototype are described.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

Project X functional requirements specification

Project X is a multi-megawatt proton facility being developed to support a world-leading program in Intensity Frontier physics at Fermilab. The facility is designed to support programs in elementary particle and nuclear physics, with possible applications to nuclear energy research. A Functional Requirements Specification has been developed in order to establish performance criteria for the Project X complex in support of these multiple missions, and to assure that the facility is designed with sufficient upgrade capability to provide U.S. leadership for many decades to come. This paper will briefly review the previously described Functional Requirements, and then discuss their recent evolution.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

Optimization of the Geometric Beta for the SSR2 Cavities of the Project X

Project X based on the 3 GeV CW superconducting Linac and is currently in the R&D phase. The CW SC Linac starts from a low-energy SCRF section (2.1 - 165 MeV) containing three different types of resonators. HWR f = 162.5 MHz (2.1 - 11 MeV) having beta= 0.11, SSR1 f = 325 MHz (11 - 35 MeV) having beta = 0.21. In this paper we present the analysis that lead to the final design of SSR2 f = 325 MHz cavity (35 - 165 MeV). We present the results of optimization of the geometric beta and the comparison between single, double and triple spoke resonators used in Project X frontend. A {beta} optimization has been carried out for the last spoke cavity section of Project X front end. The optimization process of {beta}{sub opt} for a single spoke resonator family SSR2 shown that {beta}{sub opt} = 0.47 looks better than the previous choice, which is {beta}{sub opt} = 0.4. This change can save some cavities and provide the same final energy for this section, 160 MeV. Single double and triple spoke resonator performances have been compared. The best option is the single spoke resonator SSR2 because the NTTF of a multi-spoke resonator is much narrower than a single one. In the energy range considered (40-160 MeV) the most efficient resonator is the single spoke one.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

Study of Effects of Failure of Beamline Elements and its Compensation in CW Superconducting Linac

Project-X is a proposed high intensity proton facility to be built at Fermilab in United States. The first stage consists of a superconducting linac (SC) operating in continuous wave (CW) mode to accelerate a H{sup -} beam from 2.1 MeV to 3 GeV. Failure of any beamline element during operations induces a downstream mismatch of the beam which is especially severe when the failure occurs at low energy. A large mismatch causes emittance growth and ultimately results in beam losses. In a worst case scenario, the operability of the machine may be affected and long downtime may be needed to replace the failed element. To minimize possible downtime, the optics can be designed in a way that allows local retuning to make the machine operable. This paper presents studies performed to investigate retuning scenarios after failure of an accelerating cavity or a focusing magnet at critical locations in the Project-X CW superconducting linac.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

PXIE: Project X Injector Experiment

A multi-MW proton facility, Project X, has been proposed and is currently under development at Fermilab. We are planning a program of research and development aimed at integrated systems testing of critical components comprising the front end of the Project X. This program is being undertaken as a key component of the larger Project X R&D program. The successful completion of this program will validate the concept for the Project X front end, thereby minimizing a primary technical risk element within Project X. Integrated systems testing, known as the Project X Injector Experiment (PXIE), will be accomplished with a new test facility under construction at Fermilab and will be completed over the period FY12-16. PXIE will include an H{sup -} ion source, a CW 2.1-MeV RFQ and two superconductive RF (SRF) cryomodules providing up to 25 MeV energy gain at an average beam current of 1 mA (upgradable to 2 mA). Successful systems testing will also demonstrate the viability of novel front end technologies that are expected find applications beyond Project X.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

PXIE Optics and Layout

The Project X Injector Experiment (PXIE) will serve as a prototype for the Project X front end. The aim is to validate the Project-X design and to decrease technical risks mainly related to the front end. The paper discusses the main requirements and constraints motivating the facility layout and optics. Final adjustments to the Project X front end design, if needed, will be based on operational experience gained with PXIE.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

The Project-X 3 GeV Beam Distribution System

In the Project X facility a 3 GeV H{sup -} CW beam is delivered to three users, simultaneously. This will be accomplished by selectively filling appropriate RF buckets at the front end of the linac then utilizing a RF splitter to transversely separate the bunches vertically to three different target halls. A compact TE{sub 113} squashed-wall superconducting RF cavity has been proposed to produce the initial vertical deflection. The transport line optics, cavity design parameters, and cryogenic system requirements is presented.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

Status of the Project-X CW Linac Design

Project-X is a proposed proton accelerator complex at Fermilab that would provide particle beams to support a diversified experimental program at the intensity frontier. As currently envisioned, the complex would employ a CW superconducting linac to accelerate a 1 mA average, 5 mA peak H{sup -} beam from 2.1 MeV to 3 GeV. A second superconducting linac, operating in pulsed mode would ultimately accelerate a small fraction of this beam up to 8 GeV. The CW linac is based on five families of resonators operating at three frequencies: half-wave (1 family at 162.5 MHz), spoke (2 families at 325 MHz) and elliptical (2 families at 650 MHz). Accelerating and focusing elements are assembled in cryomodules separated by short warm sections. A long open region ({approx} 15 m) allows beam extraction at 1 GeV in support of a nuclear experimental program. In this paper, we present the latest iteration of the CW linac baseline lattice. We also briefly compare it to an alternative where the 162.5 half-wave resonators are replaced with 325 MHz spoke resonators.

43 PARTICLE ACCELERATORS↗