Matching strategies for a plasma booster

This paper presents a theoretical study of a matching strategy for the laser-plasma wakefield accelerator where the injected electron beam is produced by an external source. The matching is achieved after an initial focusing using conventional beam optics, combining a linear tapering of plasma density and the increasing non linearity of the plasma wake due to the focusing of the laser driver. Both effects contribute in increasing the focusing strength from an initial relatively low value, to the considerably higher value present in the flat top plasma profile, where acceleration takes place. The same procedure is exploited to match the beam from plasma to vacuum once acceleration has occurred. Beam loading plays a crucial role both at the very beginning and end of the whole process. In the last stage, two more effects take place: a partial emittance compensation, reducing emittance value by a sizable amount, and a reduction of the energy spread, due to the relevant beam loading operating when the laser is defocused.

[1]  S. Gilardoni,et al.  Beam-wall interaction in the CERN Proton Synchrotron for the LHC upgrade , 2013 .

[2]  Eric Esarey,et al.  Laser-driven plasma-wave electron accelerators , 2009 .

[3]  V Malka,et al.  Optical transverse injection in laser-plasma acceleration. , 2013, Physical review letters.

[4]  A Mostacci,et al.  Direct measurement of the double emittance minimum in the beam dynamics of the sparc high-brightness photoinjector. , 2007, Physical review letters.

[5]  A. Gallo,et al.  The External-Injection experiment at the SPARC_LAB facility , 2014 .

[6]  G. White,et al.  High-efficiency acceleration of an electron beam in a plasma wakefield accelerator , 2014, Nature.

[7]  P Krejcik,et al.  Ionization-induced electron trapping in ultrarelativistic plasma wakes. , 2007, Physical review letters.

[8]  J. Rosenzweig,et al.  Ultracold electron bunch generation via plasma photocathode emission and acceleration in a beam-driven plasma blowout. , 2012, Physical review letters.

[9]  K. Floettmann Adiabatic matching section for plasma accelerated beams , 2014 .

[10]  J Osterhoff,et al.  High-quality electron beams from beam-driven plasma accelerators by wakefield-induced ionization injection. , 2013, Physical review letters.

[11]  Bruce E. Carlsten,et al.  New photoelectric injector design for the Los Alamos National Laboratory XUV FEL accelerator , 1989 .

[12]  Frank Tsung,et al.  Transverse emittance growth in staged laser-wakefield acceleration , 2012 .

[13]  G. Matthieussent,et al.  Eigenmodes for capillary tubes with dielectric walls and ultraintense laser pulse guiding. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[14]  Gil Travish,et al.  Adjustable, short focal length permanent-magnet quadrupole based electron beam final focus system , 2005 .

[15]  Luca Serafini,et al.  Envelope analysis of intense relativistic quasilaminar beams in rf photoinjectors:mA theory of emittance compensation , 1997 .

[16]  Eric Esarey,et al.  Physics of laser-driven plasma-based electron accelerators , 2009 .

[17]  Irene Dornmair,et al.  Emittance conservation by tailored focusing profiles in a plasma accelerator , 2015 .

[18]  E. Esarey,et al.  Beat wave injection of electrons into plasma waves using two interfering laser pulses. , 2004, Physical review. E, Statistical, nonlinear, and soft matter physics.

[19]  S. V. Bulanov,et al.  Particle injection into the wave acceleration phase due to nonlinear wake wave breaking , 1998 .

[20]  L. Serafini,et al.  Intrinsic normalized emittance growth in laser-driven electron accelerators , 2013 .

[21]  K. Floettmann Erratum: Some basic features of the beam emittance [Phys. Rev. ST Accel. Beams 6 , 034202 (2003)] , 2003 .

[22]  Mauro Migliorati,et al.  Laser-driven electron beamlines generated by coupling laser-plasma sources with conventional transport systems , 2012 .

[23]  Victor Malka,et al.  Laser-plasma lens for laser-wakefield accelerators , 2014 .