HB2018 - List of Authors (Lebedev, V.A.)

Paper	Title	Page
MOP2WA01	Beam Physics Limitations for Damping of Instabilities in Circular Accelerators	26
	V.A. Lebedev Fermilab, Batavia, Illinois, USA
	Funding: Work supported by D.O.E. Contract No. DE-AC02-07CH11359 The paper considers a beam interaction with a feedback system and major limitations on the beam damping rate. In particular, it discusses: limitations on the system gain and damping rate, feedback system noise and its effect on the beam emittance growth, x-y coupling effect on damping, suppression of high order modes and damping of slip-stacked beams.
	Slides MOP2WA01 [0.408 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-MOP2WA01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP1WB03	Experimental Study of Beam Dynamics in the PIP-II MEBT Prototype	54
	A.V. Shemyakin, J.-P. Carneiro, B.M. Hanna, V.A. Lebedev, L.R. Prost, A. Saini, V.E. Scarpine Fermilab, Batavia, Illinois, USA C.J. Richard NSCL, East Lansing, Michigan, USA V.L. Sista BARC, Mumbai, India
	Funding: This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics The Proton Improvement Plan, Stage Two (PIP-II) is a program of upgrades proposed for the Fermilab injection complex, which central part is an 800-MeV, 2-mA CW SRF linac. A prototype of the PIP-II linac front end called PIP-II Injector Test (PIP2IT) is being built at Fermilab. As of now, a 15-mA DC, 30-keV H⁻ ion source, a 2 m-long Low Energy Beam Transport (LEBT), a 2.1-MeV CW RFQ, followed by a 10-m Medium Energy Beam Transport (MEBT) have been assembled and commissioned. The MEBT bunch-by-bunch chopping system and the requirement of a low uncontrolled beam loss put stringent limitations on the beam envelope and its variation. Measurements of transverse and longitudinal beam dynamics in the MEBT were performed in the range of 1-10 mA of the RFQ beam current. Almost all measurements are made with 10 μs beam pulses in order to avoid damage to the beam line. This report presents measurements of the transverse optics with differential trajectories, reconstruction of the beam envelope with scrapers and an Allison emittance scanner, as well as bunch length measurements with a Fast Faraday Cup.
	Slides MOP1WB03 [3.750 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-MOP1WB03
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP2WA01	Optical Stochastic Cooling Experiment at the Fermilab IOTA Ring	168
	J.D. Jarvis, V.A. Lebedev, H. Piekarz, P. Piot, A.L. Romanov, J. Ruan Fermilab, Batavia, Illinois, USA M.B. Andorf, P. Piot Northern Illinois University, DeKalb, Illinois, USA
	Funding: Fermi National Accelerator Laboratory is operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy. Beam cooling enables an increase of peak and average luminosities and significantly expands the discovery potential of colliders; therefore it is an indispensable component of any modern design. Optical Stochastic Cooling (OSC) is a high-bandwidth, beam-cooling technique that will advance the present state-of-the-art, stochastic cooling rate by more than three orders of magnitude. It is an enabling technology for next-generation, discovery-science machines at the energy and intensity frontiers including hadron and electron-ion colliders. This paper presents the status of our experimental effort to demonstrate OSC at the Integrable Optics Test Accelerator (IOTA) ring, a testbed for advanced beam-physics concepts and technologies that is currently being commissioned at Fermilab. Our recent efforts are centered on the development of an integrated design that is prepared for final engineering and fabrication. The paper also presents a comparison of theoretical calculations and numerical simulations of the pickup-undulator radiation and its interaction with electrons in the kicker-undulator.
	Slides TUP2WA01 [20.009 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUP2WA01
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WEP1WA03	IBS Near Transition Crossing in NICA Collider	252
	S.A. Kostromin, A.O. Sidorin JINR, Dubna, Moscow Region, Russia I.V. Gorelyshev JINR/VBLHEP, Dubna, Moscow region, Russia V.A. Lebedev Fermilab, Batavia, Illinois, USA A.O. Sidorin Saint Petersburg State University, Saint Petersburg, Russia
	Intrabeam scattering (IBS) of charged particles in a particle beam results in an exchange of energy between different degrees of freedom. That results in an increase of average energy of particles in the beam frame and an increase of the 3D-emittance. The paper considers calculations of beam emittance growth rates for different options of NICA collider and IBS effects in close vicinity of the transition.
	Slides WEP1WA03 [1.774 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP1WA03
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP2PO010	Fermilab - The Proton Improvement Plan (PIP)	287
	F.G. Garcia, S. Chaurize, C.C. Drennan, K. E. Gollwitzer, V.A. Lebedev, W. Pellico, J. Reid, C.-Y. Tan, R.M. Zwaska Fermilab, Batavia, Illinois, USA
	The Fermilab Proton Source is composed of three machines: an injector line, a normal conducting Linac and a Booster synchrotron. The proton improvement plan was proposed in 2012 to address the necessary accelerator upgrades and hardware modification to allow an increase in proton throughput, while maintaining acceptable activation levels, ensuring viable operation of the proton source to sustain the laboratory HEP program. A summary of work performed and respective results will be presented.
	Poster WEP2PO010 [1.699 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO010
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THA1WE01	New Electron Cloud Instability Mechanism and its Detection and Suppression
	V.A. Lebedev Fermilab, Batavia, Illinois, USA S. A. Antipov CERN, Geneva, Switzerland
	Fast transverse instability was observed in Recycler proton storage ring (RR). The instability develops within 100 turns and may lead to beam loss. The fast rise suggested that the instability is driven by electron cloud. That was later supported by microwave transmission measurements. In difference to RR the instability was not observed in similar conditions in Main Injector (MI). RR is based on combined function dipoles while MI uses pure dipoles. This difference plays a key role in instability development. The instability dynamics was studied experimentally and with numerical simulations. An analytical model predicts that electrons are trapped in RR dipoles. Numerical simulations show that up to 1% of particles can be trapped. The cloud build-up is exponential with its density limited by space charge. That results in the cloud intensity orders of magnitude greater than in MI. A growth rate of about 30 turns and mode frequency of 0.4 MHz are consistent for observations and PEI simulations. The high intensity batch can be stabilized by low intensity clearing bunch injected behind batch which destroys the trapped electron cloud and prevents its multi-turn accumulation.
	Slides THA1WE01 [7.328 MB]
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP1WC03	Design of 162-MHz CW Bunch-by-Bunch Chopper and Prototype Testing Results	428
	A.V. Shemyakin, C.M. Baffes, J.-P. Carneiro, B.E. Chase, A.Z. Chen, J. Einstein-Curtis, D. Frolov, B.M. Hanna, V.A. Lebedev, L.R. Prost, G.W. Saewert, A. Saini, D. Sun Fermilab, Batavia, Illinois, USA C.J. Richard NSCL, East Lansing, Michigan, USA D. Sharma RRCAT, Indore (M.P.), India
	Funding: This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics The PIP-II program of upgrades proposed for the Fermilab accelerator complex, is centered around a 800 MeV, 2 mA CW SRF linac. A unique feature of the PIP-II linac is the capability to form a flexible bunch structure by removing a pre-programmed set of bunches from a long-pulse or CW 162.5 MHz train, coming from the RFQ, within the 2.1-MeV Medium Energy Beam Transport (MEBT) section. The MEBT chopping system consists of two travelling-wave kickers working in sync followed by a beam absorber. The prototype components of the chopping system, two design variants of the kickers and a 1/4-size absorber, have been installed in the PIP-II Injector Test (PIP2IT) accelerator and successfully tested with beam of up to 5 mA. In part, one of the kickers demonstrated a capability to create an aperiodic pulse sequence suitable for synchronous injection into the Booster while operating at 500 V and average switching frequency of 44 MHz during 0.55 ms bursts at 20 Hz. This report presents the design of the PIP-II MEBT chopping system and results of prototypes testing at PIP2IT.
	Slides THP1WC03 [4.615 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-THP1WC03
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Beam Physics Limitations for Damping of Instabilities in Circular Accelerators

26

V.A. Lebedev
Fermilab, Batavia, Illinois, USA

Funding: Work supported by D.O.E. Contract No. DE-AC02-07CH11359
The paper considers a beam interaction with a feedback system and major limitations on the beam damping rate. In particular, it discusses: limitations on the system gain and damping rate, feedback system noise and its effect on the beam emittance growth, x-y coupling effect on damping, suppression of high order modes and damping of slip-stacked beams.

Slides MOP2WA01 [0.408 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-MOP2WA01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP1WB03

Experimental Study of Beam Dynamics in the PIP-II MEBT Prototype

54

A.V. Shemyakin, J.-P. Carneiro, B.M. Hanna, V.A. Lebedev, L.R. Prost, A. Saini, V.E. Scarpine
Fermilab, Batavia, Illinois, USA
C.J. Richard
NSCL, East Lansing, Michigan, USA
V.L. Sista
BARC, Mumbai, India

Funding: This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics
The Proton Improvement Plan, Stage Two (PIP-II) is a program of upgrades proposed for the Fermilab injection complex, which central part is an 800-MeV, 2-mA CW SRF linac. A prototype of the PIP-II linac front end called PIP-II Injector Test (PIP2IT) is being built at Fermilab. As of now, a 15-mA DC, 30-keV H⁻ ion source, a 2 m-long Low Energy Beam Transport (LEBT), a 2.1-MeV CW RFQ, followed by a 10-m Medium Energy Beam Transport (MEBT) have been assembled and commissioned. The MEBT bunch-by-bunch chopping system and the requirement of a low uncontrolled beam loss put stringent limitations on the beam envelope and its variation. Measurements of transverse and longitudinal beam dynamics in the MEBT were performed in the range of 1-10 mA of the RFQ beam current. Almost all measurements are made with 10 μs beam pulses in order to avoid damage to the beam line. This report presents measurements of the transverse optics with differential trajectories, reconstruction of the beam envelope with scrapers and an Allison emittance scanner, as well as bunch length measurements with a Fast Faraday Cup.

Slides MOP1WB03 [3.750 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-MOP1WB03

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP2WA01

Optical Stochastic Cooling Experiment at the Fermilab IOTA Ring

168

J.D. Jarvis, V.A. Lebedev, H. Piekarz, P. Piot, A.L. Romanov, J. Ruan
Fermilab, Batavia, Illinois, USA
M.B. Andorf, P. Piot
Northern Illinois University, DeKalb, Illinois, USA

Funding: Fermi National Accelerator Laboratory is operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Beam cooling enables an increase of peak and average luminosities and significantly expands the discovery potential of colliders; therefore it is an indispensable component of any modern design. Optical Stochastic Cooling (OSC) is a high-bandwidth, beam-cooling technique that will advance the present state-of-the-art, stochastic cooling rate by more than three orders of magnitude. It is an enabling technology for next-generation, discovery-science machines at the energy and intensity frontiers including hadron and electron-ion colliders. This paper presents the status of our experimental effort to demonstrate OSC at the Integrable Optics Test Accelerator (IOTA) ring, a testbed for advanced beam-physics concepts and technologies that is currently being commissioned at Fermilab. Our recent efforts are centered on the development of an integrated design that is prepared for final engineering and fabrication. The paper also presents a comparison of theoretical calculations and numerical simulations of the pickup-undulator radiation and its interaction with electrons in the kicker-undulator.

Slides TUP2WA01 [20.009 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUP2WA01

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP1WA03

IBS Near Transition Crossing in NICA Collider

252

S.A. Kostromin, A.O. Sidorin
JINR, Dubna, Moscow Region, Russia
I.V. Gorelyshev
JINR/VBLHEP, Dubna, Moscow region, Russia
V.A. Lebedev
Fermilab, Batavia, Illinois, USA
A.O. Sidorin
Saint Petersburg State University, Saint Petersburg, Russia

Intrabeam scattering (IBS) of charged particles in a particle beam results in an exchange of energy between different degrees of freedom. That results in an increase of average energy of particles in the beam frame and an increase of the 3D-emittance. The paper considers calculations of beam emittance growth rates for different options of NICA collider and IBS effects in close vicinity of the transition.

Slides WEP1WA03 [1.774 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP1WA03

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP2PO010

Fermilab - The Proton Improvement Plan (PIP)

287

F.G. Garcia, S. Chaurize, C.C. Drennan, K. E. Gollwitzer, V.A. Lebedev, W. Pellico, J. Reid, C.-Y. Tan, R.M. Zwaska
Fermilab, Batavia, Illinois, USA

The Fermilab Proton Source is composed of three machines: an injector line, a normal conducting Linac and a Booster synchrotron. The proton improvement plan was proposed in 2012 to address the necessary accelerator upgrades and hardware modification to allow an increase in proton throughput, while maintaining acceptable activation levels, ensuring viable operation of the proton source to sustain the laboratory HEP program. A summary of work performed and respective results will be presented.

Poster WEP2PO010 [1.699 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO010

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THA1WE01

New Electron Cloud Instability Mechanism and its Detection and Suppression

V.A. Lebedev
Fermilab, Batavia, Illinois, USA
S. A. Antipov
CERN, Geneva, Switzerland

Fast transverse instability was observed in Recycler proton storage ring (RR). The instability develops within 100 turns and may lead to beam loss. The fast rise suggested that the instability is driven by electron cloud. That was later supported by microwave transmission measurements. In difference to RR the instability was not observed in similar conditions in Main Injector (MI). RR is based on combined function dipoles while MI uses pure dipoles. This difference plays a key role in instability development. The instability dynamics was studied experimentally and with numerical simulations. An analytical model predicts that electrons are trapped in RR dipoles. Numerical simulations show that up to 1% of particles can be trapped. The cloud build-up is exponential with its density limited by space charge. That results in the cloud intensity orders of magnitude greater than in MI. A growth rate of about 30 turns and mode frequency of 0.4 MHz are consistent for observations and PEI simulations. The high intensity batch can be stabilized by low intensity clearing bunch injected behind batch which destroys the trapped electron cloud and prevents its multi-turn accumulation.

Slides THA1WE01 [7.328 MB]

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP1WC03

Design of 162-MHz CW Bunch-by-Bunch Chopper and Prototype Testing Results

428

A.V. Shemyakin, C.M. Baffes, J.-P. Carneiro, B.E. Chase, A.Z. Chen, J. Einstein-Curtis, D. Frolov, B.M. Hanna, V.A. Lebedev, L.R. Prost, G.W. Saewert, A. Saini, D. Sun
Fermilab, Batavia, Illinois, USA
C.J. Richard
NSCL, East Lansing, Michigan, USA
D. Sharma
RRCAT, Indore (M.P.), India

Funding: This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics
The PIP-II program of upgrades proposed for the Fermilab accelerator complex, is centered around a 800 MeV, 2 mA CW SRF linac. A unique feature of the PIP-II linac is the capability to form a flexible bunch structure by removing a pre-programmed set of bunches from a long-pulse or CW 162.5 MHz train, coming from the RFQ, within the 2.1-MeV Medium Energy Beam Transport (MEBT) section. The MEBT chopping system consists of two travelling-wave kickers working in sync followed by a beam absorber. The prototype components of the chopping system, two design variants of the kickers and a 1/4-size absorber, have been installed in the PIP-II Injector Test (PIP2IT) accelerator and successfully tested with beam of up to 5 mA. In part, one of the kickers demonstrated a capability to create an aperiodic pulse sequence suitable for synchronous injection into the Booster while operating at 500 V and average switching frequency of 44 MHz during 0.55 ms bursts at 20 Hz. This report presents the design of the PIP-II MEBT chopping system and results of prototypes testing at PIP2IT.

Slides THP1WC03 [4.615 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-THP1WC03

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)