IPAC2016 - List of Authors (Mostacci, A.)

Paper	Title	Page
MOPMB017	Design Issues for the Optical Transition Radiation Screens for theELI-NP Compton Gamma Source	118
	M. Marongiu, A. Giribono, A. Mostacci, V. Pettinacci INFN-Roma, Roma, Italy D. Alesini, E. Chiadroni, F. Cioeta, G. Di Pirro, V.L. Lollo, L. Pellegrino, V. Shpakov, A. Stella, C. Vaccarezza, A. Variola INFN/LNF, Frascati (Roma), Italy A. Cianchi INFN-Roma II, Roma, Italy L. Palumbo University of Rome La Sapienza, Rome, Italy
	A high brightness electron LINAC is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32, 16 ns spaced, bunches with a nominal charge of 250 pC will collide with the laser beam in the interaction point. Electron beam spot size is measured with optical transition radiation profile monitors. In order to measure the beam properties along the train, the screens must sustain the thermal stress due to the energy deposited by the bunches; moreover the optical radiation detecting system must have the necessary accuracy and resolution. This paper deals with the analytical studies as well as numerical simulations to investigate the thermal behaviour of the screens impinged by the nominal bunch; the design and the performance of the optical detection line is discussed as well.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB017
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WEPMY007	Plasma Density Profile Characterization for Resonant Plasma Wakefield Acceleration Experiment at SPARC_LAB	2554
	F. Filippi INFN-Roma1, Rome, Italy M.P. Anania, A. Biagioni, E. Chiadroni, M. Ferrario INFN/LNF, Frascati (Roma), Italy A. Cianchi INFN-Roma II, Roma, Italy F. Filippi, A. Giribono, A. Mostacci, L. Palumbo University of Rome La Sapienza, Rome, Italy F. Filippi, A. Giribono, A. Mostacci, L. Palumbo INFN-Roma, Roma, Italy A. Giribono University of Rome "La Sapienza", Rome, Italy A. Zigler The Hebrew University of Jerusalem, The Racah Institute of Physics, Jerusalem, Israel
	New generation of particle accelerators is based on the excitation of large amplitude plasma waves driven by either electron or laser beams, named as Plasma Wakefield Accelerator (PWFA) and Laser Wakefield Accelerator (LWFA), respectively. Future experiments scheduled at the SPARC_LAB test facility aim to demonstrate the acceleration of externally injected high brightness electron beams through both schemes. In particular, in the so-called resonant PWFA a train of more than two driver electron bunches generated with the laser comb technique resonantly excites wakefields into the plasma, the last bunch (witness) is injected at the proper accelerating phase gaining energy from the wake. The quality of the accelerated beam depends strongly on plasma density and its distribution along the acceleration length. The desired density can be achieved with a correct shaping of the capillary in which plasma is formed. The measurements of plasma density, as well as other plasma characteristics, can be performed with spectroscopic measurements of the plasma self emitted light. The measurement of density distribution for hydrogen filled capillaries is here reported.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY007
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TUPMY041	Delivery Status of the ELI-NP Gamma Beam System	1635
	S. Tomassini, D. Alesini, A. Battisti, R. Boni, F. Cioeta, A. Delle Piane, E. Di Pasquale, G. Di Pirro, A. Falone, A. Gallo, S.I. Incremona, V.L. Lollo, A. Mostacci, S. Pioli, R. Ricci, U. Rotundo, A. Stella, C. Vaccarezza, A. Vannozzi, A. Variola INFN/LNF, Frascati (Roma), Italy A. Bacci, D.T. Palmer, L. Serafini Istituto Nazionale di Fisica Nucleare, Milano, Italy N. Bliss STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom F. Cardelli INFN-Roma1, Rome, Italy K. Cassou, Z.F. Zomer LAL, Orsay, France G. D'Auria Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy A. Giribono, V. Pettinacci INFN-Roma, Roma, Italy C. Hill STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom L. Palumbo Rome University La Sapienza, Roma, Italy L. Piersanti University of Rome La Sapienza, Rome, Italy
	The ELI-NP GBS is a high intensity and monochromatic gamma source under construction in Magurele (Romania). The design and construction of the Gamma Beam System complex as well as the integration of the technical plants and the commissioning of the overall facility, was awarded to the Eurogammas Consortium in March 2014. The delivery of the facility has been planned in for 4 stages and the first one was fulfilled in October 31st 2015. The engineering aspects related to the delivery stage 1 are presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY041
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MOPMB018	Metrological Characterization of the Bunch Length Measurement by Means of a RF Deflector at the ELI-NP Compton Gamma source	122
	L. Sabato U. Sannio, Benevento, Italy D. Alesini, C. Vaccarezza, A. Variola INFN/LNF, Frascati (Roma), Italy P. Arpaia CERN, Geneva, Switzerland P. Arpaia, A. Liccardo Naples University Federico II, Science and Technology Pole, Napoli, Italy A. Giribono University of Rome La Sapienza, Rome, Italy A. Mostacci, L. Palumbo Rome University La Sapienza, Roma, Italy L. Sabato INFN-Napoli, Napoli, Italy
	Bunch length measurement in linac can be carried out using a RF deflector, which provides a transverse kick to the beam. The transverse beam size on a screen, placed after the RF deflector, represents the bunch length. In this paper, the metrological characterization of the bunch length measurement technique is proposed. The uncertainty and the systematic errors are estimated by means of a sensitivity analysis to the measurement parameters. The proposed approach has been validated through simulation by means of ELEGANT code on the parameters interesting for the electron linac of the Compton source at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP).
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB018
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MOPOR010	Impedance Measurements and Simulations on the TCTP and TDI LHC Collimators	610
	N. Biancacci, F. Caspers, A. Grudiev, J. Kuczerowski, I. Lamas Garcia, A. Lechner, E. Métral, A. Passarelli, A. Perillo Marcone, B. Salvant, J.A. Uythoven CERN, Geneva, Switzerland O. Frasciello, M. Zobov INFN/LNF, Frascati (Roma), Italy A. Mostacci Rome University La Sapienza, Roma, Italy N. Mounet EPFL, Lausanne, Switzerland
	The LHC collimation system is a critical element for the safe operation of the LHC machine and is subject to continuous performance monitoring, hardware upgrade and optimization. In this work we will address the impact on impedance of the upgrades performed on the TDI injection protection collimator, where the absorber material has been changed to mitigate the device heating observed in machine operation, and on selected secondary (TCS) and tertiary (TCT) collimators, where beam position monitors (BPM) have been embedded for faster jaw alignment. Concerning the TDI, we will present the RF measurements performed before and after the upgrade, comparing the result to heating and tune shift beam measurements. For the TCTs, we will study how the higher order modes (HOM) introduced by the BPM addition have been cured by means of ferrite placement in the device. The impedance mitigation campaign has been supported by RF measurements whose results are in good agreement with GdfidL and CST simulations. The presence of undamped low frequency modes is proved not to be detrimental to the safe LHC operation.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR010
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MOPMB019	Quadrupole Scan Emittance Measurements for the ELI-NP Compton Gamma Source	126
	A.R. Rossi, A. Bacci, L. Serafini Istituto Nazionale di Fisica Nucleare, Milano, Italy E. Chiadroni, C. Vaccarezza, A. Variola INFN/LNF, Frascati (Roma), Italy A. Cianchi Università di Roma II Tor Vergata, Roma, Italy C. Curatolo, I. Drebot Universita' degli Studi di Milano e INFN, Milano, Italy A. Giribono, A. Mostacci University of Rome La Sapienza, Rome, Italy V. Petrillo, M. Rossetti Conti Universita' degli Studi di Milano & INFN, Milano, Italy
	The high brightness electron LINAC of the Compton Gamma Source at the ELI Nuclear Physics facility in Romania is accelerating a train of 32 bunches with a nominal charge of 250 pC and nominal spacing of 16 ns. To achieve the design gamma flux, all the bunches along the train must have the designed Twiss parameters. Beam sizes are measured with optical transition radiation monitors, allowing a quadrupole scan for Twiss parameters measurements. Since focusing the whole bunch train on the screen may lead to permanent screen damage, we investigated non-conventional scans such as scans around a maximum of the beam size or scans with a controlled minimum spot size. This paper discusses the implementation issues of such a technique in the actual machine layout.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB019
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MOPMR017	Design and Simulations of the Cavity BPM Readout Electronics for the ELI-NP Gamma Beam System	264
	M. Cargnelutti, B.B. Baricevic I-Tech, Solkan, Slovenia A. Mostacci University of Rome La Sapienza, Rome, Italy S. Pioli, M. Serio, A. Stella, A. Variola INFN/LNF, Frascati (Roma), Italy
	The Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility will provide a high intensity laser and a very intense gamma beam which will be used in a broad range of experiments. The gamma beam is obtained through incoherent Compton back-scattering of a laser light off a high brightness electron beam provided by a 700MeV warm LINAC. Electrons are accelerated in trains with up to 32 bunches, each one separated by 16ns. In the laser-electron interaction region, every bunch needs to be monitored with a resolution below 1μm RMS. To achieve this performance, a low-Q cavity beam position monitor will be used in combination with a dedicated data acquisition system able to perform bunch-by-bunch beam position measurements with sub-μm resolution. Using fast A/D converters and specific digital filtering, the readout system proposes an alternative measurement concept. The requirements of the system, its design and the results from the simulations will be presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR017
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MOPMW004	Realization and High Power Tests of Damped C-Band Accelerating Structures for the ELI-NP Linac	399
	D. Alesini, M. Bellaveglia, S. Bini, R. Boni, P. Chimenti, F. Cioeta, R.D. Di Raddo, A. Falone, A. Gallo, V.L. Lollo, L. Palumbo, S. Pioli, A. Variola INFN/LNF, Frascati (Roma), Italy F. Cardelli, M. Magi, A. Mostacci, L. Palumbo, L. Piersanti University of Rome La Sapienza, Rome, Italy F. Cardelli, L. Piersanti INFN-Roma1, Rome, Italy P. Favaron, F. Poletto INFN/LNL, Legnaro (PD), Italy L. Ficcadenti, F. Pellegrino, V. Pettinacci INFN-Roma, Roma, Italy
	The ELI-NP C-Band structures are 1.8 m long travelling wave accelerating structures, quasi-constant gradient, with a field phase advance per cell of 2pi/3. They operate at a repetition rate of 100 Hz and, because of the multi-bunch operation, they have been designed with a dipole HOM damping system to avoid beam break-up (BBU). The structures have symmetric input and output couplers and integrate, in each cell, a waveguide HOM damping systems with silicon carbide RF absorbers. An optimization of the electromagnetic and mechanical design has been done to simplify the fabrication and to reduce their cost. After the first full scale prototype successfully tested at the nominal gradient of 33 MV/m, the production of the twelve structures started. In the paper we illustrate the main design criteria, the realization process and the high power test results.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW004
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MOPMW007	On the Calibration Measurement of Stripline Beam Position Monitor for the ELI-NP Facility	411
	D. De Arcangelis, F. Cardelli, A. Mostacci, L. Palumbo University of Rome La Sapienza, Rome, Italy
	Stripline Beam Position Monitor (BPM) will be installed in the Compton Gamma Source in construction at the ELI Nuclear Physics facility in Romania. A test bench for the calibration of BPM has been built to characterize the device with stretched wire measurement in order to get the BPM response map. A full S-parameters characterisation is performed as well to measure the electrical offset with the "Lambertson method". This paper discusses the extensive simulations performed with full 3D electromagnetic CAD codes of the above measurements to investigate measurement accuracy, possible measurement artefacts and the beam position reconstruction.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW007
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TUPOW041	Optimization Studies for the Beam Dynamic in the RF Linac of the ELI-NP Gamma Beam System	1850
	C. Vaccarezza, D. Alesini, M. Bellaveglia, M.E. Biagini, G. Di Pirro, A. Gallo, A. Ghigo, S. Guiducci, A. Vannozzi, A. Variola INFN/LNF, Frascati (Roma), Italy A. Bacci, I. Drebot, D.T. Palmer, A.R. Rossi, L. Serafini Istituto Nazionale di Fisica Nucleare, Milano, Italy G. Campogiani Rome University La Sapienza, Roma, Italy A. Giribono, A. Mostacci, L. Palumbo University of Rome La Sapienza, Rome, Italy V. Petrillo Universita' degli Studi di Milano & INFN, Milano, Italy L. Sabbatini Consorzio Laboratorio Nicola Cabibbo, Frascati, Italy
	The ELI-NP GBS is an high spectral density and monochromatic gamma ray source based upon the inverse Compton scattering effect now under construction in Magurele. Its relevant specifications are brilliance higher than 10²¹, 0.5% monochromaticity and a 0.2-19.5 MeV energy tunability. Strong requirements are set for the electron beam dynamic: the control of both the transverse normalized emittance and the energy spread to optimize the spectral density and guarantee the mono chromaticity of the emitted radiation. On this basis the RF Linac optimization has been performed for the designed energy range; a sensitivity analysis of the machine to possible jitters, errors and so on has been also performed, the simulations results hare here presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW041
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Paper

Title

Page

Design Issues for the Optical Transition Radiation Screens for theELI-NP Compton Gamma Source

118

M. Marongiu, A. Giribono, A. Mostacci, V. Pettinacci
INFN-Roma, Roma, Italy
D. Alesini, E. Chiadroni, F. Cioeta, G. Di Pirro, V.L. Lollo, L. Pellegrino, V. Shpakov, A. Stella, C. Vaccarezza, A. Variola
INFN/LNF, Frascati (Roma), Italy
A. Cianchi
INFN-Roma II, Roma, Italy
L. Palumbo
University of Rome La Sapienza, Rome, Italy

A high brightness electron LINAC is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32, 16 ns spaced, bunches with a nominal charge of 250 pC will collide with the laser beam in the interaction point. Electron beam spot size is measured with optical transition radiation profile monitors. In order to measure the beam properties along the train, the screens must sustain the thermal stress due to the energy deposited by the bunches; moreover the optical radiation detecting system must have the necessary accuracy and resolution. This paper deals with the analytical studies as well as numerical simulations to investigate the thermal behaviour of the screens impinged by the nominal bunch; the design and the performance of the optical detection line is discussed as well.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB017

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WEPMY007

Plasma Density Profile Characterization for Resonant Plasma Wakefield Acceleration Experiment at SPARC_LAB

2554

F. Filippi
INFN-Roma1, Rome, Italy
M.P. Anania, A. Biagioni, E. Chiadroni, M. Ferrario
INFN/LNF, Frascati (Roma), Italy
A. Cianchi
INFN-Roma II, Roma, Italy
F. Filippi, A. Giribono, A. Mostacci, L. Palumbo
University of Rome La Sapienza, Rome, Italy
F. Filippi, A. Giribono, A. Mostacci, L. Palumbo
INFN-Roma, Roma, Italy
A. Giribono
University of Rome "La Sapienza", Rome, Italy
A. Zigler
The Hebrew University of Jerusalem, The Racah Institute of Physics, Jerusalem, Israel

New generation of particle accelerators is based on the excitation of large amplitude plasma waves driven by either electron or laser beams, named as Plasma Wakefield Accelerator (PWFA) and Laser Wakefield Accelerator (LWFA), respectively. Future experiments scheduled at the SPARC_LAB test facility aim to demonstrate the acceleration of externally injected high brightness electron beams through both schemes. In particular, in the so-called resonant PWFA a train of more than two driver electron bunches generated with the laser comb technique resonantly excites wakefields into the plasma, the last bunch (witness) is injected at the proper accelerating phase gaining energy from the wake. The quality of the accelerated beam depends strongly on plasma density and its distribution along the acceleration length. The desired density can be achieved with a correct shaping of the capillary in which plasma is formed. The measurements of plasma density, as well as other plasma characteristics, can be performed with spectroscopic measurements of the plasma self emitted light. The measurement of density distribution for hydrogen filled capillaries is here reported.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY007

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TUPMY041

Delivery Status of the ELI-NP Gamma Beam System

1635

S. Tomassini, D. Alesini, A. Battisti, R. Boni, F. Cioeta, A. Delle Piane, E. Di Pasquale, G. Di Pirro, A. Falone, A. Gallo, S.I. Incremona, V.L. Lollo, A. Mostacci, S. Pioli, R. Ricci, U. Rotundo, A. Stella, C. Vaccarezza, A. Vannozzi, A. Variola
INFN/LNF, Frascati (Roma), Italy
A. Bacci, D.T. Palmer, L. Serafini
Istituto Nazionale di Fisica Nucleare, Milano, Italy
N. Bliss
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
F. Cardelli
INFN-Roma1, Rome, Italy
K. Cassou, Z.F. Zomer
LAL, Orsay, France
G. D'Auria
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
A. Giribono, V. Pettinacci
INFN-Roma, Roma, Italy
C. Hill
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
L. Palumbo
Rome University La Sapienza, Roma, Italy
L. Piersanti
University of Rome La Sapienza, Rome, Italy

The ELI-NP GBS is a high intensity and monochromatic gamma source under construction in Magurele (Romania). The design and construction of the Gamma Beam System complex as well as the integration of the technical plants and the commissioning of the overall facility, was awarded to the Eurogammas Consortium in March 2014. The delivery of the facility has been planned in for 4 stages and the first one was fulfilled in October 31st 2015. The engineering aspects related to the delivery stage 1 are presented.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY041

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MOPMB018

Metrological Characterization of the Bunch Length Measurement by Means of a RF Deflector at the ELI-NP Compton Gamma source

122

L. Sabato
U. Sannio, Benevento, Italy
D. Alesini, C. Vaccarezza, A. Variola
INFN/LNF, Frascati (Roma), Italy
P. Arpaia
CERN, Geneva, Switzerland
P. Arpaia, A. Liccardo
Naples University Federico II, Science and Technology Pole, Napoli, Italy
A. Giribono
University of Rome La Sapienza, Rome, Italy
A. Mostacci, L. Palumbo
Rome University La Sapienza, Roma, Italy
L. Sabato
INFN-Napoli, Napoli, Italy

Bunch length measurement in linac can be carried out using a RF deflector, which provides a transverse kick to the beam. The transverse beam size on a screen, placed after the RF deflector, represents the bunch length. In this paper, the metrological characterization of the bunch length measurement technique is proposed. The uncertainty and the systematic errors are estimated by means of a sensitivity analysis to the measurement parameters. The proposed approach has been validated through simulation by means of ELEGANT code on the parameters interesting for the electron linac of the Compton source at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP).

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB018

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MOPOR010

Impedance Measurements and Simulations on the TCTP and TDI LHC Collimators

610

N. Biancacci, F. Caspers, A. Grudiev, J. Kuczerowski, I. Lamas Garcia, A. Lechner, E. Métral, A. Passarelli, A. Perillo Marcone, B. Salvant, J.A. Uythoven
CERN, Geneva, Switzerland
O. Frasciello, M. Zobov
INFN/LNF, Frascati (Roma), Italy
A. Mostacci
Rome University La Sapienza, Roma, Italy
N. Mounet
EPFL, Lausanne, Switzerland

The LHC collimation system is a critical element for the safe operation of the LHC machine and is subject to continuous performance monitoring, hardware upgrade and optimization. In this work we will address the impact on impedance of the upgrades performed on the TDI injection protection collimator, where the absorber material has been changed to mitigate the device heating observed in machine operation, and on selected secondary (TCS) and tertiary (TCT) collimators, where beam position monitors (BPM) have been embedded for faster jaw alignment. Concerning the TDI, we will present the RF measurements performed before and after the upgrade, comparing the result to heating and tune shift beam measurements. For the TCTs, we will study how the higher order modes (HOM) introduced by the BPM addition have been cured by means of ferrite placement in the device. The impedance mitigation campaign has been supported by RF measurements whose results are in good agreement with GdfidL and CST simulations. The presence of undamped low frequency modes is proved not to be detrimental to the safe LHC operation.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR010

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MOPMB019

Quadrupole Scan Emittance Measurements for the ELI-NP Compton Gamma Source

126

A.R. Rossi, A. Bacci, L. Serafini
Istituto Nazionale di Fisica Nucleare, Milano, Italy
E. Chiadroni, C. Vaccarezza, A. Variola
INFN/LNF, Frascati (Roma), Italy
A. Cianchi
Università di Roma II Tor Vergata, Roma, Italy
C. Curatolo, I. Drebot
Universita' degli Studi di Milano e INFN, Milano, Italy
A. Giribono, A. Mostacci
University of Rome La Sapienza, Rome, Italy
V. Petrillo, M. Rossetti Conti
Universita' degli Studi di Milano & INFN, Milano, Italy

The high brightness electron LINAC of the Compton Gamma Source at the ELI Nuclear Physics facility in Romania is accelerating a train of 32 bunches with a nominal charge of 250 pC and nominal spacing of 16 ns. To achieve the design gamma flux, all the bunches along the train must have the designed Twiss parameters. Beam sizes are measured with optical transition radiation monitors, allowing a quadrupole scan for Twiss parameters measurements. Since focusing the whole bunch train on the screen may lead to permanent screen damage, we investigated non-conventional scans such as scans around a maximum of the beam size or scans with a controlled minimum spot size. This paper discusses the implementation issues of such a technique in the actual machine layout.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB019

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MOPMR017

Design and Simulations of the Cavity BPM Readout Electronics for the ELI-NP Gamma Beam System

264

M. Cargnelutti, B.B. Baricevic
I-Tech, Solkan, Slovenia
A. Mostacci
University of Rome La Sapienza, Rome, Italy
S. Pioli, M. Serio, A. Stella, A. Variola
INFN/LNF, Frascati (Roma), Italy

The Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility will provide a high intensity laser and a very intense gamma beam which will be used in a broad range of experiments. The gamma beam is obtained through incoherent Compton back-scattering of a laser light off a high brightness electron beam provided by a 700MeV warm LINAC. Electrons are accelerated in trains with up to 32 bunches, each one separated by 16ns. In the laser-electron interaction region, every bunch needs to be monitored with a resolution below 1μm RMS. To achieve this performance, a low-Q cavity beam position monitor will be used in combination with a dedicated data acquisition system able to perform bunch-by-bunch beam position measurements with sub-μm resolution. Using fast A/D converters and specific digital filtering, the readout system proposes an alternative measurement concept. The requirements of the system, its design and the results from the simulations will be presented.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR017

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MOPMW004

Realization and High Power Tests of Damped C-Band Accelerating Structures for the ELI-NP Linac

399

D. Alesini, M. Bellaveglia, S. Bini, R. Boni, P. Chimenti, F. Cioeta, R.D. Di Raddo, A. Falone, A. Gallo, V.L. Lollo, L. Palumbo, S. Pioli, A. Variola
INFN/LNF, Frascati (Roma), Italy
F. Cardelli, M. Magi, A. Mostacci, L. Palumbo, L. Piersanti
University of Rome La Sapienza, Rome, Italy
F. Cardelli, L. Piersanti
INFN-Roma1, Rome, Italy
P. Favaron, F. Poletto
INFN/LNL, Legnaro (PD), Italy
L. Ficcadenti, F. Pellegrino, V. Pettinacci
INFN-Roma, Roma, Italy

The ELI-NP C-Band structures are 1.8 m long travelling wave accelerating structures, quasi-constant gradient, with a field phase advance per cell of 2pi/3. They operate at a repetition rate of 100 Hz and, because of the multi-bunch operation, they have been designed with a dipole HOM damping system to avoid beam break-up (BBU). The structures have symmetric input and output couplers and integrate, in each cell, a waveguide HOM damping systems with silicon carbide RF absorbers. An optimization of the electromagnetic and mechanical design has been done to simplify the fabrication and to reduce their cost. After the first full scale prototype successfully tested at the nominal gradient of 33 MV/m, the production of the twelve structures started. In the paper we illustrate the main design criteria, the realization process and the high power test results.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW004

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MOPMW007

On the Calibration Measurement of Stripline Beam Position Monitor for the ELI-NP Facility

411

D. De Arcangelis, F. Cardelli, A. Mostacci, L. Palumbo
University of Rome La Sapienza, Rome, Italy

Stripline Beam Position Monitor (BPM) will be installed in the Compton Gamma Source in construction at the ELI Nuclear Physics facility in Romania. A test bench for the calibration of BPM has been built to characterize the device with stretched wire measurement in order to get the BPM response map. A full S-parameters characterisation is performed as well to measure the electrical offset with the "Lambertson method". This paper discusses the extensive simulations performed with full 3D electromagnetic CAD codes of the above measurements to investigate measurement accuracy, possible measurement artefacts and the beam position reconstruction.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMW007

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TUPOW041

Optimization Studies for the Beam Dynamic in the RF Linac of the ELI-NP Gamma Beam System

1850

C. Vaccarezza, D. Alesini, M. Bellaveglia, M.E. Biagini, G. Di Pirro, A. Gallo, A. Ghigo, S. Guiducci, A. Vannozzi, A. Variola
INFN/LNF, Frascati (Roma), Italy
A. Bacci, I. Drebot, D.T. Palmer, A.R. Rossi, L. Serafini
Istituto Nazionale di Fisica Nucleare, Milano, Italy
G. Campogiani
Rome University La Sapienza, Roma, Italy
A. Giribono, A. Mostacci, L. Palumbo
University of Rome La Sapienza, Rome, Italy
V. Petrillo
Universita' degli Studi di Milano & INFN, Milano, Italy
L. Sabbatini
Consorzio Laboratorio Nicola Cabibbo, Frascati, Italy

The ELI-NP GBS is an high spectral density and monochromatic gamma ray source based upon the inverse Compton scattering effect now under construction in Magurele. Its relevant specifications are brilliance higher than 10²¹, 0.5% monochromaticity and a 0.2-19.5 MeV energy tunability. Strong requirements are set for the electron beam dynamic: the control of both the transverse normalized emittance and the energy spread to optimize the spectral density and guarantee the mono chromaticity of the emitted radiation. On this basis the RF Linac optimization has been performed for the designed energy range; a sensitivity analysis of the machine to possible jitters, errors and so on has been also performed, the simulations results hare here presented.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW041

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