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879. Ghaith, A. et al. Tunable High Spatio-Spectral Purity Undulator Radiation from a Transported Laser Plasma Accelerated Electron Beam. Sci. Rep. 9, 19020. doi:10.1038/s41598-019-55209-4 (2019).

880. Ghaith, A. et al. Electron Beam Brightness and Undulator Radiation Brilliance for a Laser Plasma Acceleration Based Free Electron Laser. Instruments 4, 1. doi:10.3390/instruments4010001 (2020).

881. Oumbarek Espinos, D. et al. COXINEL transport of laser plasma accelerated electrons. Plasma Phys. Control. Fusion 62, 034001 (2020).

882. Roussel, E. et al. Energy spread tuning of a laser-plasma accelerated electron beam in a magnetic chicane. Plasma Phys. Control. Fusion 62, 074003 (2020).

883. Filippi, F. et al. 3D-printed capillary for hydrogen filled discharge for plasma based experiments in RF-based electron linac accelerator. Rev. Sci. Instrum. 89, 83502. doi:10.1063/1.5010264. https://doi.org/10.1063/1.5010264
## List of EuPRAXIA Partner and Associated Partner Institutes

The EuPRAXIA Consortium consists of the following 16 partner institutes and 25 associated partner organisations. Partners are those institutes that joined the project from its beginning and received funding through the European Union's Horizon 2020 programme, while associated partners have joined the design study entirely with in-kind contributions.

### EuPRAXIA Partners

**CEA:** Commissariat à l'Énergie Atomique et aux Énergies Alternatives, 91191 Gif sur Yvette, France

**CNR:** Consiglio Nazionale delle Ricerche - Instituto Nazionale di Ottica, Via Moruzzi, 1, 56124 Pisa, Italy

**CNRS:** Centre National de la Recherche Scientifique: LPGP - LOA - LULI - LLR, Orsay & Palaiseau, France

**DESY:** Deutsches Elektronensynchrotron, Notkestr. 85, 22607 Hamburg, Germany

**ENEA:** Agenzia Nazionale per le Nuove Tecnologie, l'Energia e lo Sviluppo Economico Sostenibile - Centro Ricerche Frascati, Via Enrico Fermi, 45, 00044 Frascati (Roma), Italy

**ICL:** Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom

**INFN:** Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Frascati, Via Enrico Fermi, 40, 00044 Frascati RM, Italy

**IST:** Istituto Superior Técnico, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal

**SOLEIL:** Synchrotron SOLEIL, L'Orme des Merisiers, 91190 Saint-Aubin, France

**STFC:** Science and Technology Facilities Council: Central Laser Facility - ASTEC, Didcot & Warrington, United Kingdom

**UHH:** Universität Hamburg, Mittelweg 177, 20148 Hamburg, Germany

**ULIV:** University of Liverpool, Brownlow Hill, Liverpool, L69 7ZX, United Kingdom

**UMAN:** University of Manchester, Oxford Rd, Manchester M13 9PL, United Kingdom

**UOXF:** University of Oxford, Oxford OX1 2JD, United Kingdom

**URLS:** Sapienza Università di Roma, Piazzale Aldo Moro, 5, 00185 Roma, RM, Italy

**USTRATH:** University of Strathclyde, 16 Richmond St, Glasgow G1 1XQ, United Kingdom
EuPRAXIA Associate Partners

**CASE:** Centre for Accelerator Science and Education at Stony Brook University and Brookhaven National Laboratory, Stonybrook & Upton, United States of America

**CERN:** European Organisation for Nuclear Research, Espl. des Particules 1, 1211 Meyrin, Switzerland

**ELI:** Extreme Light Infrastructure – Beamlines, Za Radnicí 835, Dolní Břežany, 252 41 Czech Republic

**FBH:** Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany

**FZJ:** Forschungszentrum Jülich, Wilhelm-Johnen-Straße, 52428 Jülich, Germany

**HIJ:** Helmholtz-Institut Jena, Fröbelstieg 3, 07743 Jena, Germany

**HUJI:** Hebrew University of Jerusalem, Jerusalem, Israel

**HZDR:** Helmholtz-Zentrum Dresden-Rossendorf e.V., Bautzner Landstr. 400, 01328 Dresden, Germany

**IAP-RAS:** Institute of Applied Physics of the Russian Academy of Sciences, 603950 Nizhnij Novgorod, Russia

**JIHT:** Joint Institute for High Temperatures of the Russian Academy of Sciences, 125412, Izhorskaya st. 13 Bd.2, Moscow, Russia

**KIT:** Karlsruher Institut für Technologie, Karlsruhe, Germany

**KPSI:** National Institutes for Quantum and Radiological Science and Technology – Kansai Photon Science Institute, Kyoto & Hyogo, Japan

**LBNL:** Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States of America

**LMU:** Ludwig-Maximilians-Universität München, Geschwister-Scholl-Platz 1, 80539 Munich, Germany

**LU:** Lund University, 221 00 Lund, Sweden

**OU:** Osaka University, 1-1 Yamadaoka, Suita, Osaka 565-0871 Japan

**PHLAM:** Laboratoire de Physique des Lasers Atomes et Molécules, Université de Lille 1, 2 Avenue Jean Perrin, 59650 Villeneuve-d'Ascq, France

**QUB:** Queen's University Belfast, University Rd, Belfast BT7 1NN, United Kingdom

**RSC:** RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho Sayo-gun, Hyogo 679-5148 Japan

**SJTU:** Shanghai Jiao Tong University, 800 Dongchuan RD. Minhang District, Shanghai, China

**TUB:** Tsinghua University Beijing, 30 Shuangqing Rd, Haidian Qu, Beijing Shi, China

**UCLA:** University of California Los Angeles, Los Angeles, CA 90095, United States of America

**URTV:** Università degli Studi di Roma “Tor Vergata”, Via Cracovia, 50, 00133 Roma RM, Italy

**WIGNER:** Wigner Research Centre of the Hungarian Academy of Science, Konkoly-Thege Miklós út 29-33, 1121 Budapest, Hungary

**YORK:** University of York, Heslington, York YO10 5DD, United Kingdom
Commonly Used Acronyms

ALS Alignment System

APL Active Plasma Lens

ASTRA a 3D particle-tracking code [K. Floettmann, March 2017. http://www.desy.de/ mpyflo/Astra_ manual/Astra-Manual_V3.2.pdf]

BPA Beam-Driven Plasma Accelerator / Acceleration (typically referring to an entire machine or concept instead of a single stage)

BPM Beam Position Monitor

CA Clear Aperture

CB Collaboration Board

CDW Capillary Discharge Waveguide

CPA Chirped Pulse Amplification

DKDP Deuterated Potassium Dihydrogen Phosphate

DLS Diagnostics Laser System

*elegant* a 3D particle-tracking code [Borland, M. United States, 2000. doi:10.2172/761286]

EuXFEL European X-ray Free-Electron Laser, located in Hamburg, Germany

FBPIC a 3D particle-in-cell code [R. Lehe et al. Computer Physics Communications 203 (2016) 66-82, doi: 10.1016/J.CPC.2016.02.007]

FCC Facility Control-Command

FEL free-electron laser

FEP Front End Processor fs femtosecond, 1 fs=1×10⁻⁹ s

FWHM full width at half maximum

GRIN Gradient Refractive Index

HEP High-energy physics

HETL High-Energy Transfer Line

ICS inverse Compton scattering

ICT Integrated Current Transformer

LCC Laser Control-Command

LETL Low-Energy Transfer Line

LPA Laser-Driven Plasma Accelerator / Acceleration (typically referring to an entire machine or concept instead of a single stage)

LPAS Laser-Driven Plasma Acceleration Stage

LPI Laser-Plasma Injector

LPS Longitudinal Phase-Space, typically energy vs. time

LWFA laser-driven wakefield acceleration

OFI Optical Field Ionisation

PES Peaked Energy Spectrum

PIC Particle-In-Cell, a type of simulation code relevant for plasma accelerator studies

PPAS Particle-driven Plasma Acceleration Stage

PSO Particle Swarm Optimisation

PSS Personal Safety System

PW Petawatt (1PW=1×10¹⁵ W)

PWFA beam-driven wakefield acceleration

R&D research and development

RF Radiofrequency

RFI Radiofrequency Injector

RI research infrastructure

RMS root mean square (also as rms)

S2E Start-to-End (in the context of simulations)
SC Steering Committee

SSS Synchronisation and Sequencing System

TAS Target Areas Systems

TDS Transverse Deflecting Structure

*TraceWin* a 3D particle-tracking code [D. Uriot, N. Pichoff. Proc. 6th Int. Part. Acc. Conf. 2015, MOPWA008]

TW Terawatt (1 TW=1×10¹² W)

VFS Vacuum and Fluids Systems

WP Working Package
List of Figures

<table>
  <tbody>
    <tr>
      <td>1.1</td>
      <td>Partners and associated partners of the EuPRAXIA Consortium.</td>
      <td>3701</td>
    </tr>
    <tr>
      <td>1.2</td>
      <td>Project management structure of the EuPRAXIA design study.</td>
      <td>3701</td>
    </tr>
    <tr>
      <td>1.3</td>
      <td>Participants in the EuroNNAc and EuPRAXIA Workshop on a European Plasma Accelerator in Pisa, June 2016.</td>
      <td>3703</td>
    </tr>
    <tr>
      <td>1.4</td>
      <td>Comparison of size and achievable electron beam energy for different existing radiofrequency and plasma accelerators.</td>
      <td>3703</td>
    </tr>
    <tr>
      <td>1.5</td>
      <td>Basic principle of a plasma accelerator.</td>
      <td>3703</td>
    </tr>
    <tr>
      <td>1.6</td>
      <td>Small, novel plasma accelerator compared to the FLASH accelerator at DESY.</td>
      <td>3703</td>
    </tr>
    <tr>
      <td>1.7</td>
      <td>Livingston curve for accelerators, showing the maximum reach in beam energy versus time.</td>
      <td>3706</td>
    </tr>
    <tr>
      <td>1.8</td>
      <td>Schematic of the COXINEL experiment</td>
      <td>3708</td>
    </tr>
    <tr>
      <td>1.9</td>
      <td>Tomographic imaging of a mouse embryo carried out at the Gemini laser at the STFC Rutherford Appleton Laboratory.</td>
      <td>3709</td>
    </tr>
    <tr>
      <td>1.10</td>
      <td>Schematic of an open innovation model for EuPRAXIA.</td>
      <td>3711</td>
    </tr>
    <tr>
      <td>2.1</td>
      <td>Length comparison of a typical RF-based accelerator facility with the EuPRAXIA 5 GeV design.</td>
      <td>3716</td>
    </tr>
    <tr>
      <td>2.2</td>
      <td>Size, frequency, and field strength comparison of different types of RF cavities.</td>
      <td>3717</td>
    </tr>
    <tr>
      <td>2.3</td>
      <td>Comparison of different lasers and applications in terms of stored energy in a single laser pulse and repetition rate of the laser.</td>
      <td>3717</td>
    </tr>
    <tr>
      <td>2.4</td>
      <td>Comparison of user concepts in light sources and the EuPRAXIA laser-driven plasma accelerator concept.</td>
      <td>3718</td>
    </tr>
    <tr>
      <td>2.5</td>
      <td>Summary of the electron beam energy and relative energy spread for the different EuPRAXIA schemes.</td>
      <td>3718</td>
    </tr>
    <tr>
      <td>2.6</td>
      <td>Scientific fields for which the EuPRAXIA research infrastructure would be interesting based on an initial survey of potential future EuPRAXIA users.</td>
      <td>3720</td>
    </tr>
    <tr>
      <td>2.7</td>
      <td>Word cloud describing scientific fields and topics of interest relevant to potential future users of the EuPRAXIA research infrastructure.</td>
      <td>3720</td>
    </tr>
    <tr>
      <td>2.8</td>
      <td>Types of activities for which the EuPRAXIA research infrastructure would be interesting based on an initial survey of potential future EuPRAXIA users.</td>
      <td>3720</td>
    </tr>
    <tr>
      <td>2.9</td>
      <td>3D visualisation of a plasma wave excited by a high-intensity laser pulse and accelerating an electron beam generated with the VisualPIC code.</td>
      <td>3723</td>
    </tr>
    <tr>
      <td>2.10</td>
      <td>HAPLS laser at Lawrence Livermore National Laboratory.</td>
      <td>3724</td>
    </tr>
    <tr>
      <td>2.11</td>
      <td>Diffraction image of a complex biomolecule under high-intensity X-ray light.</td>
      <td>3725</td>
    </tr>
    <tr>
      <td>2.12</td>
      <td>CMS detector at the Large Hadron Collider.</td>
      <td>3727</td>
    </tr>
    <tr>
      <td>2.13</td>
      <td>Phase-contrast X-ray image of a spider.</td>
      <td>3730</td>
    </tr>
    <tr>
      <td>2.14</td>
      <td>Accelerators used for inspection and material testing.</td>
      <td>3731</td>
    </tr>
    <tr>
      <td>2.15</td>
      <td>Physical principle and context of positron annihilation spectroscopy as a material inspection technique.</td>
      <td>3732</td>
    </tr>
    <tr>
      <td>2.16</td>
      <td>Variety of possible topics and application fields at the EuPRAXIA Research Infrastructure.</td>
      <td>3735</td>
    </tr>
    <tr>
      <td>3.1</td>
      <td>EuPRAXIA facility concept.</td>
      <td>3740</td>
    </tr>
    <tr>
      <td>3.2</td>
      <td>Overview of EuPRAXIA technical clusters.</td>
      <td>3741</td>
    </tr>
    <tr>
      <td>3.3</td>
      <td>Overview of EuPRAXIA construction and excellence sites.</td>
      <td>3752</td>
    </tr>
    <tr>
      <td>3.4</td>
      <td>Schematic facility layout for the flagship construction site based on beam-driven plasma acceleration.</td>
      <td>3753</td>
    </tr>
  </tbody>
</table>
<table>
  <tbody>
    <tr>
      <td>3.5</td>
      <td>Size comparison of the EuPRAXIA infrastructure in relation to a hospital in Copenhagen.</td>
      <td>3753</td>
    </tr>
    <tr>
      <td>3.6</td>
      <td>Comparison of the expected EuPRAXIA machine length with other facilities of equivalent beam energies.</td>
      <td>3753</td>
    </tr>
    <tr>
      <td>3.7</td>
      <td>Schematic facility layout for the flagship construction site based on laser-driven plasma acceleration.</td>
      <td>3756</td>
    </tr>
    <tr>
      <td>3.8</td>
      <td>Summary of some key strategies to make data management within the EuPRAXIA collaboration more consistent with the FAIR principles.</td>
      <td>3759</td>
    </tr>
    <tr>
      <td>3.9</td>
      <td>Overview of EuPRAXIA construction and excellence sites.</td>
      <td>3759</td>
    </tr>
    <tr>
      <td>3.10</td>
      <td>Layout of the EuPRAXIA@SPARC_LAB infrastructure.</td>
      <td>3762</td>
    </tr>
    <tr>
      <td>3.11</td>
      <td>Overview of the different partners and activities involved in the LAPLACE and PALAS projects.</td>
      <td>3763</td>
    </tr>
    <tr>
      <td>3.12</td>
      <td>ELI Beamlines facility in Dolni Brezany.</td>
      <td>3769</td>
    </tr>
    <tr>
      <td>3.13</td>
      <td>Visualisation and areal view of the EPAC facility under development.</td>
      <td>3773</td>
    </tr>
    <tr>
      <td>3.14</td>
      <td>The L3 "HAPLS" laser system at the ELI Beamlines laser hall.</td>
      <td>3775</td>
    </tr>
    <tr>
      <td>3.15</td>
      <td>Possible allocation of the "laser-driven" FEL elements in the ELI Beamlines experimental areas E5 and E6.</td>
      <td>3775</td>
    </tr>
    <tr>
      <td>3.16</td>
      <td>Map and aerial view of the CNR campus in Pisa.</td>
      <td>3777</td>
    </tr>
    <tr>
      <td>3.17</td>
      <td>Layout of the Intense Laser Irradiation Laboratory at CNR-INO.</td>
      <td>3777</td>
    </tr>
    <tr>
      <td>3.18</td>
      <td>Interaction target chamber and control room at the Intense Laser Irradiation Laboratory.</td>
      <td>3777</td>
    </tr>
    <tr>
      <td>3.19</td>
      <td>Map of the CNR campus showing the INO laboratories.</td>
      <td>3777</td>
    </tr>
    <tr>
      <td>3.20</td>
      <td>The five main pillars of the EuPRAXIA long-term science programme.</td>
      <td>3780</td>
    </tr>
    <tr>
      <td>4.1</td>
      <td>Temporal profile of the foreseen investment costs.</td>
      <td>3782</td>
    </tr>
    <tr>
      <td>4.2</td>
      <td>Temporal profile of the foreseen person-power.</td>
      <td>3783</td>
    </tr>
    <tr>
      <td>4.3</td>
      <td>Preliminary study of resource distribution in Europe.</td>
      <td>3784</td>
    </tr>
    <tr>
      <td>4.4</td>
      <td>Breakdown of PWFA investment cost into technical categories.</td>
      <td>3786</td>
    </tr>
    <tr>
      <td>4.5</td>
      <td>Breakdown of LWFA investment cost into technical categories.</td>
      <td>3786</td>
    </tr>
    <tr>
      <td>5.1</td>
      <td>Main technical milestones to achieve during the EuPRAXIA technical design phase.</td>
      <td>3789</td>
    </tr>
    <tr>
      <td>5.2</td>
      <td>Preliminary project timeline.</td>
      <td>3791</td>
    </tr>
    <tr>
      <td>5.3</td>
      <td>Implementation and re-evaluation process for the EuPRAXIA project structure.</td>
      <td>3792</td>
    </tr>
    <tr>
      <td>5.4</td>
      <td>Planned management structure for the EuPRAXIA Consortium.</td>
      <td>3792</td>
    </tr>
    <tr>
      <td>5.5</td>
      <td>Main user categories expected at EuPRAXIA.</td>
      <td>3794</td>
    </tr>
    <tr>
      <td>5.6</td>
      <td>Summary of the proposed access modes for users at EuPRAXIA.</td>
      <td>3795</td>
    </tr>
    <tr>
      <td>5.7</td>
      <td>List of the main technical risks associated with each major sub-system of EuPRAXIA.</td>
      <td>3801</td>
    </tr>
    <tr>
      <td>6.1</td>
      <td>Map of large-scale user facilities providing access to similar types of particle and radiation sources as EuPRAXIA will offer.</td>
      <td>3804</td>
    </tr>
    <tr>
      <td>6.2</td>
      <td>Map of areas of impact expected through EuPRAXIA.</td>
      <td>3807</td>
    </tr>
    <tr>
      <td>6.3</td>
      <td>Positioning of EuPRAXIA in the technological accelerator landscape of the next decades.</td>
      <td>3811</td>
    </tr>
    <tr>
      <td>7.1</td>
      <td>Wakefield generation and electron beam acceleration in a plasma accelerator.</td>
      <td>3813</td>
    </tr>
    <tr>
      <td>7.2</td>
      <td>Examples of different types of plasma sources used in plasma injectors and accelerators.</td>
      <td>3819</td>
    </tr>
    <tr>
      <td>7.3</td>
      <td>Operating principle of chirped pulse amplification (CPA) and optical parametric chirped pulse amplification (OPCPA).</td>
      <td>3820</td>
    </tr>
    <tr>
      <td>7.4</td>
      <td>Operating principle of a free-electron laser (FEL).</td>
      <td>3823</td>
    </tr>
    <tr>
      <td>8.1</td>
      <td>Overview layout of the EuPRAXIA site for beam-driven plasma acceleration.</td>
      <td>3826</td>
    </tr>
  </tbody>
</table>
<table>
  <tbody>
    <tr>
      <td>8.2</td>
      <td>Overview layout of the EuPRAXIA site for laser-driven plasma acceleration.</td>
      <td>3826</td>
    </tr>
    <tr>
      <td>8.3</td>
      <td>Beam distribution and acceleration configurations under consideration for the various EuPRAXIA beamlines.</td>
      <td>3830</td>
    </tr>
    <tr>
      <td>10.1</td>
      <td>Block diagram of the three laser driver chains.</td>
      <td>3839</td>
    </tr>
    <tr>
      <td>10.2</td>
      <td>Amplifier head geometries.</td>
      <td>3843</td>
    </tr>
    <tr>
      <td>10.3</td>
      <td>Schematic structure of the twin amplifying crystals in the transmission geometry, along with the cooling flow arrangement.</td>
      <td>3844</td>
    </tr>
    <tr>
      <td>10.4</td>
      <td>Top view of the general layout of the amplifier crystals for the transmission geometry for a six-pass arrangement.</td>
      <td>3845</td>
    </tr>
    <tr>
      <td>10.5</td>
      <td>Beam paths for the injection in the Ti:Sapphire crystals.</td>
      <td>3845</td>
    </tr>
    <tr>
      <td>10.6</td>
      <td>AMP3 multipass layout.</td>
      <td>3846</td>
    </tr>
    <tr>
      <td>10.7</td>
      <td>Overview of the synchronisation scheme for the implementation of the EDP strategy.</td>
      <td>3847</td>
    </tr>
    <tr>
      <td>10.8</td>
      <td>Simulation of the fluid velocity distribution in the cooling channel.</td>
      <td>3849</td>
    </tr>
    <tr>
      <td>10.9</td>
      <td>Temperature profile along the crystal surface and effective film coefficient for different flow speeds.</td>
      <td>3849</td>
    </tr>
    <tr>
      <td>10.10</td>
      <td>Ridge fluid simulations.</td>
      <td>3849</td>
    </tr>
    <tr>
      <td>10.11</td>
      <td>Wall-plug efficiency comparison between different laser architectures.</td>
      <td>3855</td>
    </tr>
    <tr>
      <td>10.12</td>
      <td>Extraction efficiency</td>
      <td>3855</td>
    </tr>
    <tr>
      <td>11.1</td>
      <td>Hardware architecture for the control-command system.</td>
      <td>3860</td>
    </tr>
    <tr>
      <td>11.2</td>
      <td>Schematic of the beamline divided into different zones.</td>
      <td>3867</td>
    </tr>
    <tr>
      <td>11.3</td>
      <td>Scheme of timing and synchronisation.</td>
      <td>3869</td>
    </tr>
    <tr>
      <td>12.1</td>
      <td>Gun fields.</td>
      <td>3871</td>
    </tr>
    <tr>
      <td>12.2</td>
      <td>SPARC Gun Solenoid.</td>
      <td>3873</td>
    </tr>
    <tr>
      <td>12.3</td>
      <td>Solenoid coils embedding the first accelerating S-band structure.</td>
      <td>3875</td>
    </tr>
    <tr>
      <td>12.4</td>
      <td>Layout of the EuPRAXIA S-band RF power station.</td>
      <td>3877</td>
    </tr>
    <tr>
      <td>12.5</td>
      <td>Pulse compression with a SLED-type system.</td>
      <td>3880</td>
    </tr>
    <tr>
      <td>12.6</td>
      <td>Effective shunt impedance as a function of the section attenuation and resulting accelerating field profile.</td>
      <td>3880</td>
    </tr>
    <tr>
      <td>12.7</td>
      <td>Basic EuPRAXIA X-band accelerating cell.</td>
      <td>3881</td>
    </tr>
    <tr>
      <td>12.8</td>
      <td>Characteristics of the TW accelerating section as a function of iris radius.</td>
      <td>3882</td>
    </tr>
    <tr>
      <td>12.9</td>
      <td>Schematics of an 8-section X-band RF module.</td>
      <td>3883</td>
    </tr>
    <tr>
      <td>13.1</td>
      <td>Plasma density profile for the LPI using a density downramp.</td>
      <td>3887</td>
    </tr>
    <tr>
      <td>13.2</td>
      <td>Beam properties for the density downramp LPI.</td>
      <td>3888</td>
    </tr>
    <tr>
      <td>13.3</td>
      <td>Schematic view of the target cell used in the simulation.</td>
      <td>3889</td>
    </tr>
    <tr>
      <td>13.4</td>
      <td>Longitudinal density profile for different lengths of the exit tube.</td>
      <td>3889</td>
    </tr>
    <tr>
      <td>13.5</td>
      <td>Laser evolution inside the ionisation injection plasma target.</td>
      <td>3890</td>
    </tr>
    <tr>
      <td>13.6</td>
      <td>Energy distribution of the electrons at the exit of the ionisation injection plasma target.</td>
      <td>3890</td>
    </tr>
    <tr>
      <td>13.7</td>
      <td>Schematic of the laser removal and coupling in a multi-stage configuration.</td>
      <td>3894</td>
    </tr>
    <tr>
      <td>14.1</td>
      <td>Layout of the SPARC-like RF photo-injector.</td>
      <td>3899</td>
    </tr>
    <tr>
      <td>14.2</td>
      <td>Charge distribution at the cathode surface produced by the photocathode laser pulse.</td>
      <td>3900</td>
    </tr>
    <tr>
      <td>14.3</td>
      <td>Evolution of the witness beam parameters along the injector in the case of pure RF compression.</td>
      <td>3900</td>
    </tr>
    <tr>
      <td>14.4</td>
      <td>Beam distribution at the photo-injector exit.</td>
      <td>3902</td>
    </tr>
    <tr>
      <td>14.5</td>
      <td>Longitudinal phase space of the LWFA-accelerated electron beam at the L2 linac exit.</td>
      <td>3902</td>
    </tr>
    <tr>
      <td>14.6</td>
      <td>Start-to-end simulation results for the witness bunch from the photocathode to the undulator entrance.</td>
      <td>3902</td>
    </tr>
  </tbody>
</table>
<table>
  <tbody>
    <tr>
      <td>14.7</td>
      <td>Start-to-end simulation results for the witness bunch from the photo-cathode to the undulator entrance.</td>
      <td>3902</td>
    </tr>
    <tr>
      <td>14.8</td>
      <td>Injection layout for the hybrid compression scheme.</td>
      <td>3904</td>
    </tr>
    <tr>
      <td>14.9</td>
      <td>Transverse beam size and normalised emittance evolutions from the photo-cathode to the linac exit.</td>
      <td>3905</td>
    </tr>
    <tr>
      <td>14.10</td>
      <td>Beam optics from the linac exit to the injection point.</td>
      <td>3905</td>
    </tr>
    <tr>
      <td>14.11</td>
      <td>Transverse and longitudinal phase spaces of the beam at the linac exit and the injection point.</td>
      <td>3906</td>
    </tr>
    <tr>
      <td>14.12</td>
      <td>Longitudinal phase space of the PWFA-accelerated electron beam at the L2 linac exit.</td>
      <td>3907</td>
    </tr>
    <tr>
      <td>14.13</td>
      <td>Transverse and longitudinal distributions of the photo-cathode laser at the cathode surface.</td>
      <td>3907</td>
    </tr>
    <tr>
      <td>14.14</td>
      <td>Transverse distribution of the comb beam used for PWFA</td>
      <td>3908</td>
    </tr>
    <tr>
      <td>14.15</td>
      <td>Driver and witness beam energy and current profiles after velocity bunching.</td>
      <td>3908</td>
    </tr>
    <tr>
      <td>14.16</td>
      <td>Horizontal and vertical phase-space distribution of the PWFA driver and witness beams at the L1 linac entrance.</td>
      <td>3910</td>
    </tr>
    <tr>
      <td>14.17</td>
      <td>Transverse RMS size of the electron beam (driver plus witness) along the linac.</td>
      <td>3910</td>
    </tr>
    <tr>
      <td>14.18</td>
      <td>Horizontal and vertical phase-space distribution of the PWFA driver and witness beams at the capillary entrance.</td>
      <td>3910</td>
    </tr>
    <tr>
      <td>14.19</td>
      <td>Transverse horizontal and vertical distribution of the PWFA driver and witness beams at the capillary entrance.</td>
      <td>3910</td>
    </tr>
    <tr>
      <td>14.20</td>
      <td>Start-to-end simulation results for the driver bunch from the photo-cathode to the undulator entrance showing emittance and spot size.</td>
      <td>3910</td>
    </tr>
    <tr>
      <td>14.21</td>
      <td>Start-to-end simulation results for the witness beam from the photo-cathode to the undulator entrance showing emittance and spot size.</td>
      <td>3910</td>
    </tr>
    <tr>
      <td>14.22</td>
      <td>Start-to-end simulation results for the driver bunch from the photo-cathode to the undulator entrance showing energy, energy spread and bunch length.</td>
      <td>3910</td>
    </tr>
    <tr>
      <td>14.23</td>
      <td>Start-to-end simulation results for the witness beam from the photo-cathode to the undulator entrance showing energy, energy spread and bunch length.</td>
      <td>3910</td>
    </tr>
    <tr>
      <td>15.1</td>
      <td>Schematic view of the synchronising stage.</td>
      <td>3914</td>
    </tr>
    <tr>
      <td>15.2</td>
      <td>On-axis longitudinal electric field after 1.2 mm of propagation in the plasma, with the electron beam placed at the zero crossing.</td>
      <td>3916</td>
    </tr>
    <tr>
      <td>15.3</td>
      <td>Beta function and emittance evolution for beams with different offsets.</td>
      <td>3917</td>
    </tr>
    <tr>
      <td>15.4</td>
      <td>Jitter correction thanks to plasma stage and chicane.</td>
      <td>3918</td>
    </tr>
    <tr>
      <td>16.1</td>
      <td>Schematic of the proposed developments at the two EuPRAXIA construction sites, with the plasma accelerator stages circled.</td>
      <td>3919</td>
    </tr>
    <tr>
      <td>16.2</td>
      <td>Example and simulation of different capillary tubes.</td>
      <td>3922</td>
    </tr>
    <tr>
      <td>16.3</td>
      <td>Schematic of the laser removal and coupling in a multi-stage configuration.</td>
      <td>3924</td>
    </tr>
    <tr>
      <td>17.1</td>
      <td>Electron bunch and background density after 5 mm of propagation in the plasma.</td>
      <td>3929</td>
    </tr>
    <tr>
      <td>17.2</td>
      <td>Phase-space and slice analysis of the driver and witness at the plasma exit.</td>
      <td>3930</td>
    </tr>
    <tr>
      <td>17.3</td>
      <td>Electron bunch and background density after 15 mm of plasma.</td>
      <td>3930</td>
    </tr>
    <tr>
      <td>17.4</td>
      <td>Evolution of the witness parameters and phase space in the 5 GeV case.</td>
      <td>3932</td>
    </tr>
    <tr>
      <td>17.5</td>
      <td>Rolling slice analysis for the witness bunch at the plasma input and exit for the 5 GeV case.</td>
      <td>3934</td>
    </tr>
    <tr>
      <td>18.1</td>
      <td>RADIA model and magnetic field of a cryogenic undulator with a 12 mm period.</td>
      <td>3944</td>
    </tr>
  </tbody>
</table>
<table>
  <tbody>
    <tr>
      <td>18.2</td>
      <td>Deflection parameter versus gap for different period undulators using RADIA.</td>
      <td>3945</td>
    </tr>
    <tr>
      <td>18.3</td>
      <td>Typical magnet design for an SCU viewed from the side.</td>
      <td>3946</td>
    </tr>
    <tr>
      <td>18.4</td>
      <td>Transverse gradient undulator scheme.</td>
      <td>3949</td>
    </tr>
    <tr>
      <td>19.1</td>
      <td>Layout of the low-energy beam transfer line.</td>
      <td>3951</td>
    </tr>
    <tr>
      <td>19.2</td>
      <td>Beam parameters along a low-energy transfer line of six quadrupoles.</td>
      <td>3951</td>
    </tr>
    <tr>
      <td>19.3</td>
      <td>Beam slice parameters along a low-energy transfer line of six quadrupoles.</td>
      <td>3952</td>
    </tr>
    <tr>
      <td>19.4</td>
      <td>Beam parameters along a low-energy transfer line of eight quadrupoles.</td>
      <td>3954</td>
    </tr>
    <tr>
      <td>19.5</td>
      <td>Beam slice parameters along a low-energy transfer line of eight quadrupoles.</td>
      <td>3954</td>
    </tr>
    <tr>
      <td>19.6</td>
      <td>Magnetic field profile in a 1 mm diameter active plasma lens.</td>
      <td>3956</td>
    </tr>
    <tr>
      <td>19.7</td>
      <td>Beam parameters along a low-energy transfer line of two active plasma lenses.</td>
      <td>3956</td>
    </tr>
    <tr>
      <td>19.8</td>
      <td>Beam slice parameters along a low-energy transfer line of two active plasma lenses.</td>
      <td>3956</td>
    </tr>
    <tr>
      <td>19.9</td>
      <td>Layout of the high-energy beam transfer line.</td>
      <td>3959</td>
    </tr>
    <tr>
      <td>19.10</td>
      <td>Beam parameters along the high-energy transfer line for Scheme 1.</td>
      <td>3961</td>
    </tr>
    <tr>
      <td>19.11</td>
      <td>Beam slice parameters along the high-energy transfer line for Scheme 1.</td>
      <td>3962</td>
    </tr>
    <tr>
      <td>19.12</td>
      <td>Beam parameters along the high-energy transfer line for Scheme 2.</td>
      <td>3963</td>
    </tr>
    <tr>
      <td>19.13</td>
      <td>Beam slice parameters along the high-energy transfer line for Scheme 2.</td>
      <td>3963</td>
    </tr>
    <tr>
      <td>19.14</td>
      <td>Beam parameters along the high-energy transfer line for Scheme 3.</td>
      <td>3963</td>
    </tr>
    <tr>
      <td>19.15</td>
      <td>Beam slice parameters along the high-energy transfer line for Scheme 3.</td>
      <td>3963</td>
    </tr>
    <tr>
      <td>19.16</td>
      <td>Illustrative representation of the accelerator beamline of Scheme 4.</td>
      <td>3963</td>
    </tr>
    <tr>
      <td>19.17</td>
      <td>Beam parameters along the high-energy transfer line between the two LPAS for Scheme 4.</td>
      <td>3967</td>
    </tr>
    <tr>
      <td>19.18</td>
      <td>Current profile of the beam before and after the chicane in Scheme 4.</td>
      <td>3967</td>
    </tr>
    <tr>
      <td>19.19</td>
      <td>Beam parameters along the high-energy transfer line after the second LPAS for Scheme 4.</td>
      <td>3967</td>
    </tr>
    <tr>
      <td>19.20</td>
      <td>Beam slice parameters along the high-energy transfer line after the second LPAS for Scheme 4.</td>
      <td>3967</td>
    </tr>
    <tr>
      <td>19.21</td>
      <td>Beam parameters along the high-energy transfer line for Scheme 5.</td>
      <td>3967</td>
    </tr>
    <tr>
      <td>19.22</td>
      <td>Beam slice parameters along the high-energy transfer line for Scheme 5.</td>
      <td>3967</td>
    </tr>
    <tr>
      <td>20.1</td>
      <td>Interferometric measurement capability for neutral molecular hydrogen.</td>
      <td>3976</td>
    </tr>
    <tr>
      <td>20.2</td>
      <td>Interferometric measurement capability for free electrons.</td>
      <td>3976</td>
    </tr>
    <tr>
      <td>21.1</td>
      <td>Temporary beamline for the electron diagnostics after the LPI.</td>
      <td>3988</td>
    </tr>
    <tr>
      <td>21.2</td>
      <td>Layout of the permanent beamline for electron diagnostics between the LPI and LPAS.</td>
      <td>3989</td>
    </tr>
    <tr>
      <td>21.3</td>
      <td>Layout of the diagnostics in the electron gun section of SINBAD-ARES.</td>
      <td>3990</td>
    </tr>
    <tr>
      <td>21.4</td>
      <td>Layout of the diagnostics in the linac section of ARES.</td>
      <td>3990</td>
    </tr>
    <tr>
      <td>21.5</td>
      <td>Layout of the diagnostics in the beam-matching section of SINBAD-ARES.</td>
      <td>3990</td>
    </tr>
    <tr>
      <td>21.6</td>
      <td>Layout of the diagnostics for the RF injector at EuPRAXIA@SPARC_LAB.</td>
      <td>3990</td>
    </tr>
    <tr>
      <td>21.7</td>
      <td>Layout of the diagnostics for a section of the linac at EuPRAXIA@SPARC_LAB.</td>
      <td>3991</td>
    </tr>
    <tr>
      <td>21.8</td>
      <td>Layout of the matching optics and diagnostics setup behind the plasma booster.</td>
      <td>3992</td>
    </tr>
    <tr>
      <td>22.1</td>
      <td>SwissFEL Aramis beam stopper.</td>
      <td>3996</td>
    </tr>
    <tr>
      <td>22.2</td>
      <td>Beam longitudinal phase space after 8.5 cm in plasma.</td>
      <td>3999</td>
    </tr>
    <tr>
      <td>22.3</td>
      <td>Density profile used to eliminate the re-acceleration of particles in the bunch tail.</td>
      <td>3999</td>
    </tr>
    <tr>
      <td>22.4</td>
      <td>Beam longitudinal phase space after 21 cm in plasma.</td>
      <td>3999</td>
    </tr>
    <tr>
      <td>22.5</td>
      <td>Energy plots as a function of propagation distance in plasma.</td>
      <td>3999</td>
    </tr>
  </tbody>
</table>
<table>
  <tbody>
    <tr>
      <td>23.1</td>
      <td>The accelerator schemes under investigation.</td>
      <td>4002</td>
    </tr>
    <tr>
      <td>23.2</td>
      <td>Beam parameters obtained at the LPI exit.</td>
      <td>4006</td>
    </tr>
    <tr>
      <td>23.3</td>
      <td>Beam parameters obtained at the LPAS exit.</td>
      <td>4006</td>
    </tr>
    <tr>
      <td>23.4</td>
      <td>Scheme 1 using a single-stage injector / accelerator generating an FEL-quality 5 GeV beam.</td>
      <td>4012</td>
    </tr>
    <tr>
      <td>23.5</td>
      <td>Visualisation of the ReMPI scheme</td>
      <td>4012</td>
    </tr>
    <tr>
      <td>23.6</td>
      <td>Driver train evolution.</td>
      <td>4014</td>
    </tr>
    <tr>
      <td>23.7</td>
      <td>On-axis snapshot at the early stage of bunch trapping.</td>
      <td>4015</td>
    </tr>
    <tr>
      <td>23.8</td>
      <td>Phase space of the bunch at the end of the 25 cm long capillary.</td>
      <td>4016</td>
    </tr>
    <tr>
      <td>23.9</td>
      <td>Phase-space cuts of the final beam.</td>
      <td>4017</td>
    </tr>
    <tr>
      <td>23.10</td>
      <td>Longitudinal phase-space plot and current profile of the final beam.</td>
      <td>4017</td>
    </tr>
    <tr>
      <td>23.11</td>
      <td>Slice analysis with a slice thickness of 0.1 µm.</td>
      <td>4017</td>
    </tr>
    <tr>
      <td>23.12</td>
      <td>Evolution of the beam parameters from Scheme 1 along the HETL.</td>
      <td>4017</td>
    </tr>
    <tr>
      <td>23.13</td>
      <td>Sensitivity of the accelerating field on the resonance condition mismatch.</td>
      <td>4020</td>
    </tr>
    <tr>
      <td>23.14</td>
      <td>Scheme 2 combining a 150 MeV laser-plasma injector with an LPAS to 5 GeV.</td>
      <td>4021</td>
    </tr>
    <tr>
      <td>23.15</td>
      <td>The longitudinal normalised electric field, resonantly excited by a train of laser pulses.</td>
      <td>4021</td>
    </tr>
    <tr>
      <td>23.16</td>
      <td>The longitudinal phase-space density of the bunch close to the end of the injection process and at the end of the acceleration phase.</td>
      <td>4021</td>
    </tr>
    <tr>
      <td>23.17</td>
      <td>Electron beam phase space (position vs. normalised momentum p/mc) at the end of the acceleration phase.</td>
      <td>4022</td>
    </tr>
    <tr>
      <td>23.18</td>
      <td>Twiss parameters and chromatic length along the plasma downramp and the passive plasma lens.</td>
      <td>4023</td>
    </tr>
    <tr>
      <td>23.19</td>
      <td>Evolution of the beam size and emittance along the LETL.</td>
      <td>4025</td>
    </tr>
    <tr>
      <td>23.20</td>
      <td>Transverse and longitudinal phase spaces at the plasma exit of Scheme 2.</td>
      <td>4025</td>
    </tr>
    <tr>
      <td>23.21</td>
      <td>Beam emittance and RMS size evolution along the upramp of the LPAS.</td>
      <td>4026</td>
    </tr>
    <tr>
      <td>23.22</td>
      <td>Evolution of the Twiss parameter γ and the normalised phase-space emittance ε<sub>ph,n</sub> along the downramp and the downstream drift.</td>
      <td>4027</td>
    </tr>
    <tr>
      <td>23.23</td>
      <td>Evolution of the beam parameters from Scheme 2 along the HETL.</td>
      <td>4028</td>
    </tr>
    <tr>
      <td>23.24</td>
      <td>Scheme 3 combining a 500 MeV RF injector with an LPAS to 5 GeV.</td>
      <td>4028</td>
    </tr>
    <tr>
      <td>23.25</td>
      <td>Evolution of the beam parameters along the RF injector.</td>
      <td>4030</td>
    </tr>
    <tr>
      <td>23.26</td>
      <td>Beam properties at the capillary entrance.</td>
      <td>4031</td>
    </tr>
    <tr>
      <td>23.27</td>
      <td>Transverse and longitudinal phase spaces at the accelerator exit in Scheme 3.</td>
      <td>4032</td>
    </tr>
    <tr>
      <td>23.28</td>
      <td>Evolution of beam parameters during plasma acceleration.</td>
      <td>4032</td>
    </tr>
    <tr>
      <td>23.29</td>
      <td>Slice characteristics along the beam.</td>
      <td>4032</td>
    </tr>
    <tr>
      <td>23.30</td>
      <td>Evolution of the beam parameters from Scheme 3 along the HETL.</td>
      <td>4033</td>
    </tr>
    <tr>
      <td>23.31</td>
      <td>Overview of the proposed acceleration scheme and the evolution of the longitudinal phase space of the beam along the two-stage dechirping concept.</td>
      <td>4035</td>
    </tr>
    <tr>
      <td>23.32</td>
      <td>Overview of the two-stage accelerator beamline for EuPRAXIA.</td>
      <td>4036</td>
    </tr>
    <tr>
      <td>23.33</td>
      <td>On-axis density profile of the two plasma stages.</td>
      <td>4036</td>
    </tr>
    <tr>
      <td>23.34</td>
      <td>Transverse and longitudinal phase space of the electron beam as delivered by the RF linac at the entrance of the first plasma.</td>
      <td>4037</td>
    </tr>
    <tr>
      <td>23.35</td>
      <td>Evolution of the longitudinal phase space of the externally injected electron beam along the beamline.</td>
      <td>4037</td>
    </tr>
    <tr>
      <td>23.36</td>
      <td>Comparison of the current profiles of the original and smoothed beams.</td>
      <td>4038</td>
    </tr>
    <tr>
      <td>23.37</td>
      <td>Evolution of the parameters of the core part of the beam along both plasma stages.</td>
      <td>4038</td>
    </tr>
    <tr>
      <td>23.38</td>
      <td>Transverse and longitudinal phase space of the improved (smoothed) beam after the second plasma stage.</td>
      <td>4039</td>
    </tr>
  </tbody>
</table>