Modern and Future Colliders
- Shiltsev, Vladimir et al
- arXiv:2003.09084FERMILAB-PUB-19-481-AD-APC
 | Schematics of particle collider types. |
 | Center of mass energy reach of particle colliders vs their start of operation. Solid and dashed lines indicate a ten-fold increase per decade for hadron (circles) and lepton (triangles) colliders (adapted from \cite{shiltsev2012}). |
 | Luminosities of particle colliders (triangles are lepton colliders and full circles are hadron colliders, adapted from \cite{shiltsev2012}). |
 | Cross section of the 14.3 m long superconducting magnet of the Large Hadron Collider \cite{evans2016lhcdipolecrosssection}. The design field of 8.33 T is vertical and opposite in the two 56 mm diameter bores for the two counter-rotating beams, with a horizontal beam-to-beam separation of 194 mm. The LHC comprises 1232 main dipoles, each weighing about 35 tons. |
 | The baseline superconducting cavity package (“dressed cavity”) of the International Linear Collider; the titanium helium tank is shown as transparent for a view of the 1 m long 9-cell niobium RF cavity inside (adapted from \cite{phinney2007ilc}). |
 | Angular kick due to beam-beam force. |
 | The Stanford Linear Collider (SLC). Polarized electrons are produced by photoemission from a Ti:sapphire laser and a GaAs photocathode at the electron gun, accelerated to 1.2 GeV, injected into a damping ring (DR) to reduce $e^-$ beam emittance (size), then kicked back into the 3 km long linac to be accelerated together with positrons to 46.6 GeV, then separated magnetically and transported along two arcs and collide head-on at the IP. The positrons are produced by a fraction of 30 GeV $e^-$ beam which is stopped in a target. $e^+$'s are then collected and returned to the upstream end of the linac for many-fold emittance reduction in another DR (from \cite{friedsam1990slcalignment}). |
 | Schematic view of the LEP injector chain of accelerators and the LEP storage ring \cite{pcpb} with the four experiments ALEPH, DELPHI, L3, and OPAL. The first part of the chain of injectors, the LEP pre-injector (LPI), consisted of two LEP injector linacs (LIL) and an electron/positron storage ring (EPA). Eight positron bunches, followed by eight electron bunches, were ejected from EPA to the Proton Synchrotron (PS), and then accelerated plus extracted to the Super Proton Synchrotron (SPS) for further acceleration. Positrons and electrons were injected into LEP from the SPS, initially at a beam energy of 20 GeV, and later (since 1995) at 22 GeV, to boost the bunch current, which was limited at injection by the TMCI. In its last year of operation (2000), the LEP reached a maximum e$^+$e$^-$ collision energy of 209 GeV. |
 | Top: beam collision scheme with crossing angle suffers from geometric luminosity reduction. Bottom: crab-crossing scheme that results in full bunch overlapping and thus maximum luminosity. Deflecting RF cavities generate a null kick to the center of the bunch while its head and tail receive opposite transverse kicks (from \cite{verdu2016crabcavities}). |
 | Layout of the Fermilab accelerator complex. The accelerators are shown to scale; the radius of the Tevatron is 1.0 km. Proton beam energy out of the linac is 400 MeV and 8 GeV out of the Booster synchrotron; the energy of antiprotons in the antiproton source (triangular shape Debuncher and Accumulator) is also 8 GeV (from \cite{holmes2013legacy}). |
 | Crab waist collision scheme \protect\cite{zobovhandbook}. |
 | Crab waist collision scheme \protect\cite{zobovhandbook}. |
 | Schematic of SuperKEKB (Courtesy: KEK). |
 | Layout of the RHIC collider with its injector complex \cite{ranjbar}. The two RHIC rings cross in six points. The two principal experiments still running are PHENIX and STAR. The smaller experiments PHOBOS, BRAHMS and PP2PP have been completed. The LINAC is the injector for polarized protons into the Booster/AGS/RHIC chain. A jet target used for precision beam polarization measurements. A tandem injector for ions has been replaced by an Electron Beam Ion Source (EBIS) starting with the 2012 run. |
 | Layout of the LHC double ring, with its eight long straight sections hosting two general and two special-purpose experimental detectors and/or devoted to specific accelerator functions, such as betatron collimation (cleaning), momentum collimation, beam extraction, RF systems and diagnostics, and injection. (Image credit: CERN). |
 | Integrated yearly luminosity between 2011 and 2018 for proton operation (from \cite{lhcipac2019operation}). |
 | Superferric 1.8 T magnets of the NICA collider: a) (left) cross-section of the magnet, based on a cold, window-frame iron yoke and a hollow superconductor winding: 1 --- lamination, 2 --- SC cable, 3 --- yoke cooling tube, 4 --- beam pipe, 5 --- current carrying bus bars. The magnets are placed in a 4.5 K cryostat (not shown); b) (right) 10.4 kA SC cable: 1 --- 3 mm diameter cooling tube, 2 --- Nb-Ti SC wire, 3 --- Ni-Cr wire, 4 and 5 --- insulation tapes (adapted from \cite{khodzhibagiyan2019nicamagnets}). |
 | Conceptual layout of the planned electron(antiproton)-ion collider hosting the ELISe experiment. The intersection region $A-B$ is situated in a bypass section to the New Experimental Storage Ring (NESR) and hosts a dedicated spectrometer (from \cite{antonov2011elise}). |
 | Layout of the Jefferson Lab Electron-Ion Collider (JLEIC) (from \cite{zhang2019jleic}). |
 | Average $e-p$ luminosity of JLEIC and eRHIC as a function of c.m.e. The JLEIC average luminosity takes into account a 75\% operational duty factor and is given for both baseline design (open circles) and for a potential future upgrade with a 400 GeV proton ring (solid circles). The eRHIC luminosity is averaged over the data-taking cycle and equals 95\% of the peak luminosity. |
 | Layout of the eRHIC interaction region. The length scales for the horizontal and vertical axis are very different. Beams cross with a crossing angle of 25 mrad. The IR design integrates focusing magnets for both beams, luminosity and neutron detectors, electron taggers, spectrometer magnets, near-beam detectors (Roman pots for hadrons), crab cavities, and spin rotators for both beams (from \cite{willeke2019erhic}). |
 | Schematic layout of the ILC in the 250 GeV staged configuration (from \cite{ilc2019global}). |
 | Luminosity of the proposed Higgs and electroweak factories vs center of mass energy $\sqrt{s}=2E_b$. |
 | 3D model of the CLIC two-beam RF module (adapted from \cite{accel:CLIC}). |
 | CLIC accelerator complex layout at $\sqrt{s}$=380 GeV \cite{stapnes2019layout}. |
 | Beamstrahlung effects in ILC and CLIC luminosity --- fraction of the luminosity within 1\% of c.m.e.~vs.~energy. |
 | Positron production rates achieved at the SLC, KEKB and SuperKEKB compared with the need for top-up injection at future circular and linear e$^+$e$^-$ colliders (also in Ref.~\protect\cite{fcc-nature}). |
 | Asymmetric final-focus optics of FCC-ee, featuring four sextupoles (a--d) for local vertical chromaticity correction combined with a virtual crab waist (see text for details) \protect\cite{oideoptics,fccee}. |
 | Layout of the FCC-ee double ring collider with two long RF straights and two interactions points, sharing a tunnel with the full-energy top-up booster \protect\cite{oideoptics,fccee}. |
 | Study boundary (red polygon), showing the main topographical and geological structures, LHC (blue line) and FCC tunnel trace (brown line) \protect\cite{fccee,fcchh}. |
 | Field limits for LHC-type Nb-Ti conductor, Nb$_{3}$Sn conductor as used for HL-LHC, FCC-hh and HE-LHC, and iron-based superconductor (present and 10-year forecast) for SppC (after P.J.~Lee \protect\cite{plee}, and private communication J.~Gao). |
 | A periodic unit of the FCC-hh vacuum beamscreen, which will be mounted inside the magnet cold bore (1.9 K) \protect\cite{perez}. This beamscreen will be operated at an elevated temperature of about 50 K for efficient removal of the heat from synchrotron radiation. |
 | Tunnel cross sections for FCC-hh, SppC, and HE-LHC, approximately to scale (from Ref.~\cite{Benedikt-NIMA}). |
 | Energy reach of muon-muon collisions: the energy at which the proton collider cross-section equals that of a muon collider (from Ref.~\cite{delahaye2019arxiv}). The dashed line assumes comparable Feynman amplitudes for muon and proton production processes. |
 | Schematic of a 4 TeV Muon Collider on the 6$\times$7 km FNAL site (from Ch.12.2 Ref. \cite{myers2013accelerators}). |
 | Ionization cooling-channel section. 200 MeV muons lose energy in lithium hydrate (LiH) absorbers (blue) that is replaced when the muons are reaccelerated in the longitudinal direction in RF cavities (green). The few-Tesla SC solenoids (red) confine the beam within the channel and radially focus the beam at the absorbers. Some representative component parameters are also shown (from Ref.\cite{geer2009}). |
 | Simulated six-dimensional (6D) cooling path \cite{palmer2014muonrast} corresponding to one particular candidate muon collider cooling channel. The first part of the scheme (blue ellipse) is identical to the present baseline neutrino factory front end (from Ref.\cite{geer2009}). |
 | Concept of the plasma wakefield acceleration driven either by a short laser pulse (LWFA), or by a short electron bunch or by long(er) modulated proton bunch (PWFA, adapted from \cite{assmann2014plasmaquality}). |
 | A 0.1 nC electron bunch gained a maximum energy of 9 GeV in a 1.3 m-long electron plasma wakefield accelerator driven by a 20.35 GeV $e^-$ beam at the FACET facility at SLAC: (a)-(d) show the energetically dispersed transverse charge density profile spectra and the horizontally integrated spectral charge density profiles as observed on the wide-field of view Cherenkov screen and on the order of magnitude more sensitive Lanex screen, respectively (from Ref.~\cite{litos20169gev}). |
 | Basic ERL principle: accelerating bunches take energy from SRF linac, while decelerating bunches return energy back \cite{litvinenko2019fccerl}. |
 | (top) Scheme of $\gamma \gamma$ , $\gamma e$ collider; (bottom) Higgs production diagram in $\gamma \gamma$ collisions (from Ref.\cite{telnov2014photonhiggs}). |
 | Scanning electron microscope image of the longitudinal cross-section of a dielectric laser acceleration structure with 400 nm gap \cite{peralta2013dlademonstration}. |
 | Approximate technically limited timelines of future large colliding beam facilities. |