Two-pass two-way acceleration in a superconducting continuous wave linac to drive low jitter x-ray free electron lasers

@article{ ISI:000496585000002,
Author = {Bacci, A. and Conti, M. Rossetti and Bosotti, A. and Cialdi, S. and Di
   Mitri, S. and Drebot, I and Faillace, L. and Ghiringhelli, G. and
   Michelato, P. and Monaco, L. and Opromolla, M. and Paparella, R. and
   Petrillo, V and Placidi, M. and Puppin, E. and Rossi, A. R. and Rossi,
   G. and Sertore, D. and Serafini, L.},
Title = {{Two-pass two-way acceleration in a superconducting continuous wave linac
   to drive low jitter x-ray free electron lasers}},
Journal = {{PHYSICAL REVIEW ACCELERATORS AND BEAMS}},
Year = {{2019}},
Volume = {{22}},
Number = {{11}},
Month = {{NOV 13}},
Abstract = {{We present a design study of an innovative scheme to generate high rep
   rate (MHz-class) GeV electron beams by adopting a two-pass two-way
   acceleration in a superconducting (SC) linac operated in continuous wave
   (CW) mode. The electron beam is accelerated twice by being reinjected in
   opposite direction of propagation into the linac after the first
   passage. Acceleration in opposite directions is accomplished thanks to
   standing waves supported in rf cavities. The task of recirculating the
   electron beam when it leaves the linac after first pass is performed by
   a bubble-shaped arc compressor composed by a sequence of double bend
   achromat. In this paper we address the main issues inherent to the
   two-pass acceleration process and the preservation of the electron beam
   quality parameters (emittance, energy spread, peak current) required to
   operate x-ray free electron lasers (FEL) with low jitters in the
   amplitude, spectral and temporal domain, as achieved by operating in
   seeding and/or oscillator mode a CW FEL up to 1 MHz rep rate. Detailed
   start-to-end simulations are shown to assess the capability of this new
   scheme to double the electron beam energy as well as to compress the
   electron bunch length from picoseconds down to tens of femtoseconds. The
   advantage of such a scheme is to halve the requested linac length for
   the same final electron beam energy, which is typically in the few GeV
   range, as needed to drive an x-ray FEL. The AC power to supply the
   cryogenic plant is also significantly reduced with respect to a
   conventional single-pass SC linac for the same final energy. We are
   reporting also x-ray FEL simulations for typical values of wavelengths
   of interest (in the 200 eV-8 keV photon energy range) to better
   illustrate the potentiality of this new scheme.}},
Publisher = {{AMER PHYSICAL SOC}},
Address = {{ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA}},
Type = {{Article}},
Language = {{English}},
Affiliation = {{Bacci, A (Corresponding Author), Ist Nazl Fis Nucl, Sez Milano, Via Celoria 16, I-20133 Milan, Italy.
   Bacci, A (Corresponding Author), LASA, Via F Cervi 201, I-20090 Segrate, MI, Italy.
   Bacci, A.; Conti, M. Rossetti; Bosotti, A.; Cialdi, S.; Drebot, I; Faillace, L.; Michelato, P.; Monaco, L.; Opromolla, M.; Paparella, R.; Petrillo, V; Puppin, E.; Rossi, A. R.; Sertore, D.; Serafini, L., Ist Nazl Fis Nucl, Sez Milano, Via Celoria 16, I-20133 Milan, Italy.
   Bacci, A.; Conti, M. Rossetti; Bosotti, A.; Cialdi, S.; Drebot, I; Faillace, L.; Michelato, P.; Monaco, L.; Opromolla, M.; Paparella, R.; Petrillo, V; Puppin, E.; Rossi, A. R.; Sertore, D.; Serafini, L., LASA, Via F Cervi 201, I-20090 Segrate, MI, Italy.
   Cialdi, S.; Opromolla, M.; Petrillo, V; Rossi, G., Univ Milan, Via Festa Perdono 7, I-20100 Milan, Italy.
   Di Mitri, S., Elettra Sincrotrone Trieste SCpA, I-34149 Trieste, Italy.
   Ghiringhelli, G.; Puppin, E., Politecn Milan, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy.
   Placidi, M., Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA.}},
DOI = {{10.1103/PhysRevAccelBeams.22.111304}},
Article-Number = {{111304}},
ISSN = {{2469-9888}},
Keywords-Plus = {{BEAMS}},
Research-Areas = {{Physics}},
Web-of-Science-Categories  = {{Physics, Nuclear; Physics, Particles & Fields}},
Author-Email = {{alberto.bacci@mi.infn.it}},
ResearcherID-Numbers = {{Conti, Marcello Rossetti/AAB-2597-2019
   Ghiringhelli, Giacomo/D-1159-2014
   Di Mitri, Simone/AAC-8114-2020
   }},
ORCID-Numbers = {{Conti, Marcello Rossetti/0000-0002-5767-3850
   Ghiringhelli, Giacomo/0000-0003-0867-7748
   Di Mitri, Simone/0000-0001-6453-144X
   Bacci, Alberto Luigi/0000-0001-6010-9225
   Opromolla, Michele/0000-0002-6760-6512
   Faillace, Luigi/0000-0002-1305-6201}},
Number-of-Cited-References = {{46}},
Times-Cited = {{2}},
Usage-Count-Last-180-days = {{1}},
Usage-Count-Since-2013 = {{1}},
Journal-ISO = {{Phys. Rev. Accel. Beams}},
Doc-Delivery-Number = {{JN0HG}},
Unique-ID = {{ISI:000496585000002}},
OA = {{DOAJ Gold, Green Published}},
DA = {{2020-12-22}},
}