Intro (J. List)
Topic 1: Stages and physics goals from 91 GeV to 800-1000 GeV (M.Peskin)
Topic 2: ILC at CERN compared to FCC-ee (R.Pöschl)
Topic 3: SCRF / ILC-like realization of full physics program 91-1000 GeV (S. Michizono)
Topic 4: CLIC/C3 realization of full physics program as upgrade of ILC250 (S.Stapnes)
Topic 5: RELIC upgrade of ILC250 and physics need for higher luminosity...
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In the upcoming generation of collider experiments, such as the proposed Linear Collider Higgs Factory, precise measurement of particle flow (PF) is pivotal for enhancing the energy resolution of jets, which consist of numerous hadrons observed in the final state. To achieve this, we focus on equipping fine-segmented electromagnetic calorimeters with high-precision time measurement...
The AWAKE project at CERN makes use of plasma to transfer energy from the SPS proton beam to a short witness beam of electrons. We here give an overview of the project, from the exploitation of beam-plasma instabilities to generate large accelerating fields, to the next stages of the project, which will demonstrate sustained accelerating gradients and control of the witness bunch emittance. ...
For the success of the International Linear Collider (ILC), it is crucial for the project to be accepted and integrated within the local communities. This requires close cooperation between the ILC Laboratory and the surrounding municipalities to develop "next-generation city planning initiatives triggered by the ILC" that bring extensive and diverse value to the region. Furthermore, it is...
Dark Matter being electrically neutral does not participate in electromagnetic interactions at leading order. However, we discuss here fermionic dark matter (DM) with permanent magnetic and electric dipole moment that interacts electromagnetically with photons at loop-level through a dimension-5 operator. We discuss the search prospect of the dark matter at the proposed International Linear...
The BELLA Center has been pursuing laser and laser-plasma accelerator (LPA) research for high energy physics. One of the ultimate goals is to provide a building block for future linear colliders. At the flagship 1-Hz 1-PW laser facility, the development of a 10-GeV class LPA module is ongoing, and such modules in series are envisioned as the path to a high energy collider at TeV energies and...
Neutrino oscillation is a phenomenon where the neutrino oscillates between its flavor states while propagating. This comes as a result of neutrino flavor states being eigenstates of the weak interaction Hamiltonian but not of the propagation Hamiltonian. The latter possesses different eigenstates called the mass states. The change of basis between these states is described by a unitary matrix...
Transformers are one of the recent big achievements of machine learning, which enables realistic communication on natural language processing such as ChatGPT, as well as being applied to many other fields such as image processing. The basic concept of a Transformer is to learn relation between two objects by an attention mechanism. This structure is especially efficient with large input...
The existence of dark matter is currently one of the strong motivations for beyond the standard model. We consider the model of the composite dark matter. Our model assumes that meson-like dark matter (call it dark mesons) is a bounded state of dark quark ($\psi$) and anti-dark quark ($\bar{\psi}$) pairs, where $\psi$ and $\bar{\psi}$ have a confining force at work. Confining force is based on...
We have developed the energy calibration method by using the machine learning for the ILC EM calorimeter (ECAL), a sampling calorimeter consisting with Silicon-Tungsten layers.
In this method, we use deep neural network (DNN) to get the energy of the incident particle (energy calibration), as a regression problem,
to improve the energy calibration resolution of ECAL.
We have developed the...
The International Linear Collider (ILC) is an electron-positron linear collider to explore physics beyond the Standard Model of particle physics in the center of mass energy of 250 GeV to 1 TeV.
In the TDR, to make a positron, a helical undulator of more than 150 m long will be planning to insert in the main electron linac.
And in parallel, to mitigate the risks associated with the...
We study Majorana Right Handed Neutrinos (RHN) production at ILC. Various extensions of the SM aim to explain the origin of the tiny neutrino mass; one of them is by the introduction of RHN. When we assume that RHN is a Majorana particle, RHN pair production is allowed in e−e+ collisions. We focus on this RHN pair production based on a minimal U(1)B−L model. A distinctive signature is a pair...
Superconducting radio-frequency cavities made of pure bulk niobium (Nb) is an essential tool in modern accelerator science and technology. Nb superconducting radio-frequency (SRF) cavities can extremely efficiently accelerate charged particles. At the High Energy Accelerator Research Organization(KEK), Tesla-shaped 1.3 GHz Nb SRF cavities has been developed for next-generation accelerator...
We study the W pair production at future lepton colliders. For the production of longitudinally polarized W bosons, it is well known that large gauge cancellation occurs among the amplitudes, especially at high energies, because of the energy growth of each amplitude. In this study, we adopt a recently-proposed gauge fixing, so-called Feynman-Diagram gauge and revisit the process to show such...
Minimal dark matter is one of the most motivated dark matter candidates, and many analyses at collider experiments for this model have been discussed. In our work, we considered the search for minimal dark matter at future high-energy lepton collider experiments. We found that the indirect search, which measures the quantum correction to the muon elastic scattering, is much more sensitive than...
Highly compact and granular sandwich silicon tungsten calorimeters are part of the detector concepts proposed for all future Higgs Factories and for strong-field-QED (LUXE) or Dark Matter search experiments. This contribution discusses some of the technological challenges of sensor-electronics hybridization for this type of calorimeters. Different alternatives have been explored and used in...
The HALHF concept utilises beam-driven plasma-wakefield acceleration to accelerate electrons to very high energy and collide them with much lower-energy positrons accelerated in a conventional RF linac. This idea, which avoids difficulties in the plasma acceleration of positrons, has been used to design a Higgs factory that is much smaller, cheaper, and greener than any based solely on...
Invited talk on Higgs measurements at the LHC and HL-LHC
We generalize a native Nb2O5 dissolution model [G. Ciovati, Appl. Phys. Lett. 89, 022507 (2006)] to sequential overlayer dissolutions, multilayer dissolution, and realistic temperature profiles, which may be applicable to other materials. The model is applied to secondary ion mass spectrometry depth profile measurements for varying temperature profiles and two-step oxide dissolution in Nb and...
The CEPC Linac is a normal conducting S-band and C-band combined Linac providing electron and positron beams at an energy up to 30 GeV with 100 Hz repetition. The positron source of CEPC adopts a conventional scheme, electron beam energy on the target is 4GeV with a 10nC bunch charge. This talk will introduce the design of CEPC positron sources, including positron generation, capture,...
Despite successfully predicting the outcome of hundreds of measurements at colliders and other experiments, the standard model of particle physics cannot be the final theory of nature. Searches for beyond-the-standard model (BSM) physics are now a major component of the research program at the ATLAS and CMS experiments at the Large Hadron Collider (LHC). This talk presents highlights of BSM...
IJCLab has been leading development and deployment of low-beta SRF cavities for proton and heavy ion accelerators.
We are launching a new project for sustainable Energy Recovery Linac (iSAS/PERLE) with state-of-the-art SRF cavities at 800 MHz.
Our proposal includes advanced heat treatment of such cavities to reach excellent quality factor at high fields.
In this talk, we overview the status...
A baseline concept for a continuous wave (CW) polarized positron injector was developed for the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab (Ce+BAF) [1]. This concept is based on positron beam generation by a high current polarized electron beam (1 mA, 120 MeV, 90% polarization) irradiating a water-cooled, 4 mm thick rotating tungsten target or suitable alternative....
Some say SUSY is dead, because LHC has not discovered it yet. But is this
really true? It turns out that the story is more subtle. SUSY can be 'just
around the corner', even if no signs of it has been found and a closer
look is needed to quantify the impact of LHC limits and their implications
for future colliders. Here, a scan of the relevant parameter space of
(weak-scale) SUSY...
We study possible CP-violation effects of the Higgs to $Z$-boson coupling
at a future $e^+ e^-$ collider, e.g. the International Linear Collider (ILC). We find that the azimuthal angular distribution of the muon pair, produced by $e^+ e^- \rightarrow H Z -> H \mu^+ \mu^-$, can be sensitive to such a CP-violation effect when we apply initial transversely polarized beams. Based on this angular...
Several future collider experiments are proposed for precise measurement of Higgs that require calorimeter technology with excellent jet energy resolution. To fulfill the requirement, this study aims to develop next-generation calorimetry that combines "particle flow calorimetry" and "dual-readout calorimetry". For the aspect of particle flow calorimetry, highly segmented readouts are...
There is growing interest in the gamma-gamma configurations of multi-TeV PWFA colliders since they do not require positrons or flat beams and may have the same particle physics potential as multi-TeV electron positron or muon anti-muon colliders. In this report the CAIN Monte Carlo is used to study the luminosity spectra of several gamma-gamma configurations assuming a round beam 15 TeV...
Recently ATLAS and CMS published search results in the search for SUSY particle production channel $pp \to \tilde\chi_2^0 \tilde\chi^\pm_1$ in three different final states ($3l$, $2l$ and mono-jet). All searches in both experiments show consistent (small) excesses for $m_{\tilde\chi^0_2} \approx m_{\tilde\chi^\pm_1} \approx m_{\tilde\chi^0_1} + 20$ GeV. We discuss these excesses and their...
Final states with spin-correlations allow the measurement of quantum entanglement at collider energies. The $H\to\tau\tau$ process is an excellent probe for this, due to the scalar nature of the Higgs boson, and the direct access to the $\tau$-lepton helicity through the angular distributions of the $\tau$-lepton decay products. We will present the prospects of such a measurement a future...
A Higgs Factory is considered the highest priority next collider project by the high-energy physics community. Very advanced designs based on radio-frequency cavities exist, and variations on this approach are still being developed. Recently, also an option based on electron-bunch driven plasma wakefield acceleration has been proposed. In this article, we discuss a further option based on...
The Kyoto-KEK sX mapping system was applied to the vertical testing of a 805 MHz 6-cell SNS high-beta cavity (HB60) aimed at localizing field emitters in the cavity. The test result will be presented and implication to the on-going effort in the battle against field emission in current and future SRF cavities will be discussed.
The proposal for a new generation high-luminosity electron-positron collider, the Super Tau-Charm Facility (STCF), has been put forward in China. The STCF is expected to achieve a luminosity greater than 0.5×1035 cm-2 s-1 and operate within a center-of-mass energy range of 2 to 7 GeV. Considering the design challenges of the STCF collider ring, swap-out injection has been suggested as one of...
The future e+e- colliders offer excellent facilities for SUSY searches. The stau, superpartner of the tau-lepton, is one of the most interesting particles for these searches, being likely the lightest of the sfermions, first one that could be observed, and it can be regarded as the worst and thus most general scenario for the searches.
The prospects for discovering stau-pair production at...
ATF2 status and operation 2023-2024 will be presented.
In this contribution we report on the development of a cavity tuner for a cryomodule, which is being developed and will be built and tested in the scope of the International Linear Collider (ILC) Technology Network (ITN) at KEK until 2027. We have simulated Lorentz-force detuning of the according SRF 1.3 GHz 9-cell TESLA-type cavities to understand the tuner requirements better. As a base of...
Recently, compelling evidence of nanohertz gravitational waves is indicated by the pulsar timing array collaborations. In this talk, I will present an MeV-scale first-order phase transition from a minimal dark sector to explain the gravitation waves, with a focus on the collider tests via a minimal Higgs portal. I will demonstrate that to explain the observed gravitational waves, the Higgs...
The proposed sub-tunnels are considered necessary for the construction, installation and operation of the BDS and beam dump. It would also provide access to facilities such as a laser room for polarimetry, a preparation room for beam dump experiments and magnet power supply rooms.
A constantly updated 3D CAD model will also be presented.
The detectors at future e+e- linear colliders will need unprecedented precision on Higgs physics measurements. These ambitious physics goals translate into very challenging detector requirements on tracking and calorimetry. Monolithic Active Pixel Sensor (MAPS) technology offers small dead areas, thin sensors, and small pixels over large areas. Future e+e- Colliders could benefit from O(ns)...
The electro-weak couplings of the top quark are directly accessible in rare "top+X" production processes at the LHC, where top quark pairs or single top quark are produced in associations with bosons. We present a new analysis of the top sector of the Standard Model EFT. The fit is based on a fully NLO parameterization and includes the most recent (differential) results from ATLAS and CMS. We...
The first Southern Hemisphere X-band Laboratory for Accelerators and Beams (X-LAB) has been commissioned at the University of Melbourne. One of the key projects within this laboratory involves repurposing half of the CERN X-band test stand XBOX3, now known as Mel-BOX.
This initiative aims to validate the performance of high-gradient travelling wave accelerating structures, crucial for the...
Wakefield study at ATF2 beamline will be presented.
The development schedule of the ILC Central Area affects the assembly and installation schedule of the detectors, which in turn significantly impacts the overall ILC construction schedule. We conducted a detailed study of the process required for constructing the ILC at the Kitakami site in Japan, from the start of construction until the assembly of detectors can be started. The results of...
The study is based on the publication of EPJC 83, 269 (2023).
We present a study of top quark mass measurements at the t\bar{t} threshold based on CEPC. A centre-of-mass energy scan near two times of the top mass is performed and the measurement precision of top quark mass, width and \alpha_S are evaluated using the t\bar{t} production rates. Realistic scan strategies at the threshold are...
KEK ATF Linac and Damping Ring klystrons High-Power RF field phase will be presented.
We present a new viable benchmark scenario under the current experimental data for the model which can explain the tiny mass of active neutrinos and dark matter. Majorana masses of right handed neutrinos are given by the spontaneous breaking of the U(1)B-L gauge symmetry at the TeV scale, and tiny neutrino mass are radiatively induced by quantum effects of particles of the dark sector...
On site magnet winding
The RF power distribution system for the International Linear Collider (ILC) is redesigned based on the updated requirements established in the scope of the ILC Technology Network (ITN) at KEK. Its main features are a low center of gravity, a compact design, and a reduced number of waveguide components. The power distribution system design is updated to avoid interference among various...
Two new TPCs have been installed and commissioned at JPARC, as part of the upgraded T2K near detector long baseline neutrino experiment. It makes use of the ‘Encapsulated Resistive Anode Micromegas’ (ERAM) technology, developed in the last decade for the ILC TPC.
The characterization of the ERAM modules in X-ray tests, the modeling of the signal formation and of the charge spreading process,...
This presentation details the design and fabrication process of a prototype of a normal-conducting X-band accelerator structure, which we denominate Smartcell. These structures, achieved through brazing/bonding techniques, are crucial components for future linear colliders.
We will cover the brazing/bonding geometry, materials selection and their implications, variations in heat cycles, and...
In this talk, I will discuss the potential discovery of top quark flavor changing neutral current (FCNC) at future linear colliders (LCs). First, I will discuss the theoretical predictions in a class of simplified dark matter models where the rates of top quark FCNC decays are generated by dark-sector particles. I will then discuss the sensitivity of the LCs on the top quark FCNC for some...
Muon colliders offer exciting new opportunities to explore the Standard Model and beyond by unifying the energy and precision frontiers, thus also facilitating deeper insight into the Higgs sector central to the Standard Model. In this work, motivated by recent developments in anti-muon cooling, we explore the prospects of Higgs production at \mu^+ \mu^+ colliders. At high energies, Higgs...
Ultra-low Beta* experimental studies at ATF2 and future plans will be presented.
News on big solenoids
In complement to the development activities for fusion reactors (JT-60SA & ITER), Fusion for Energy contributes to the R&D for material characterisation facilities. Within the Broader Approach agreement, different actors from Europe to Japan collaborate to develop and assemble in Japan the LIPAC, a technical demonstrator of a D+ accelerator that will be used to produce neutron by nuclear...
In order to test and discriminate the extended Higgs models, it is quite important to include radiative corrections to the analyses for the synergy between the precise measurements of the discovered Higgs boson (h125) and the direct searches for additional Higgs bosons. Deviations of couplings of h125 from the standard model (SM) predictions give the upper limit on masses of additional Higgs...
ILC C-BPMs status and plans will be presented.
For ILD, one of the detector concepts for the proposed International Linear Collider, a time projection chamber (TPC) is foreseen as the central tracking detector. The R&D effort within the LCTPC collaboration has been centred around a common infrastructure setup operated at the DESY II Test Beam Facility. This setup includes a large field cage as test bed for the different readout...
I present the status of the ECFA Higgs/EW/Top Factory workshop activities for the ttbar-threshold focus topic (see https://arxiv.org/pdf/2401.07564).
An expert team has been setup aiming to provide a firm basis for the projected precision of the top quark mass and width measurements from a scan of the center-of-mass energy through the top quark pair production threshold. The prospects for...
A dielectric assist accelerating (DAA) structure, which consists special dielectric cell structures operating in the TM02n mode, is greatly superior in power efficiency compared with the conventional normal conducting copper structures. On the other hand, DAA structures stays at a low achievable accelerating gradient due to multipactor and breakdowns. To overcome these problems, we try to...
Belle II IP Chamber
The existence of additional Higgs bosons, besides the one
discovered by the LHC, already a decade ago, is predicted by most
frameworks of new physics. Observation of a second Higgs boson
(charged or neutral) will thus provide a firm evidence that the
underlying manifestation of the Electroweak Symmetry Breaking (EWSB)
mechanism is a non-minimal one. The majority of analyses,...
SRF materials such as niobium have been extremely useful for accelerator technology but require low temperature operation ~4K. The development of high temperature superconductors (HTS) is promising due to their operating temperatures being closer to that of liquid nitrogen ~77K. This work hopes to determine the high-power RF performance of such materials at X-band (11.424 GHz). We have tested...
An introduction to the Industrial Forum on Accelerator Technologies and Advanced Instrumentation for Future Linear Colliders and Sustainability Plenary session will be given. Experience from the previous LCWS workshops will be summarized. This talk is also intended to highlight the efforts ongoing within the LDG WG on "Sustainability Assessment of Future Accelerators" and to receive a feedback...
The Advanced Accelerator Association Promoting Science & Technology (AAA) is a general incorporated association. The objective of the association shall strive in facilitating the industry-government-academia collaboration. It seeks the industrial applications of advanced accelerators and technologies with the International Linear Collider (ILC) as its core project, as well as the scientific...
Fragmentation functions (FFs) are essential non-perturbative inputs for precision calculations of hadron production cross sections in high energy scattering from first principle of QCD. They are usually extracted from global analysis on world data from single inclusive hadron production at lepton colliders, semi-inclusive DIS and pp collisions, e.g., as in recent NPC23 analysis. Future lepton...
Exploring long-range angular correlations among emitted particles in high-energy collisions provides an opportunity to uncover physics beyond the Standard Model like Hidden Valley (HV) models.
We focus on a hidden QCD-like sector, where the interplay between HV matter and QCD partonic cascades could enhance azimuthal correlations between final-state particles. Our investigation, performed at...
Attention-based transformer models have become increasingly prevalent in collider analysis, offering enhanced performance for tasks such as jet tagging. However, they are computationally intensive and require substantial data for training. In this paper, we introduce a new jet classification network using an MLP mixer, where two subsequent MLP operations serve to transform particle and feature...
As CEPC-SppC Industrial Promotion Consortium, CIPC is an industrial collaborative organization in China that supports CEPC. It currently has nearly a hundred member units and aims to jointly tackle key technologies, cultivate industrialization, and promote the orderly development of manufacturing, technology, and engineering processes in China's industry. The report introduces the CIPC's...
Since 2007, CERN has been fabricating normal conducting structures in collaboration with industry. With PSI joining some years later, only academic institutions have been pushing for further developments of high gradient structures manufacturing in Europe.
This trend appears to be changing with growing interest from European industry, recognizing the potential of high gradient, X-band...
To enhance the scientific discovery power of high-energy collider experiments, we propose and realize the concept of jet origin identification that categorizes jets into 5 quark species (b, c, s, u, d), 5 anti-quarks (¯b, ¯c, ¯s, ¯u, ¯ d), and the gluon. Using state-of-the-art algorithms and simulated ν¯νH,H →jj events at 240 GeV center-of-mass energy at the electron-positron Higgs factory,...
Electroweak Precision Measurements are stringent tests of the Standard Model and sensitive probes to New Physics. Accurate studies of the Z-boson couplings to the first-generation quarks could reveal potential discrepancies between the fundamental theory and experimental data. Future e+e- colliders running at the Z pole and around the ZH threshold would be an excellent tool to perform such a...
The possibility of a Gamma-Gamma collider extension to the Beam
dump of the $17.5$ GeV European XFEL has been discussed before as
a first high energy collider of its sort. It would not just be to study
the concept of a gamma-gamma collider but this collider would also
be without competition in the region of $5− 12$ GeV for gamma-gamma
physics. In this range $b\bar{b}$ and $c\bar{c}$...
International Linear Collider (ILC) is a next-generation e+e- linear collider to explore Beyond-Standard-Models by precise measurements of Higgs bosons. Jet flavor tagging plays a vital role in the ILC project by identification of H->bb,cc,gg,ss to measure Higgs coupling constants and of HH->bbbb and bbWW which are the main channels to measure the Higgs self-coupling constant.
Jet Flavor...
Our recent work has shown that a novel, much higher granularity
forward calorimetry concept can enable much more detailed and precise
reconstruction than the baseline designs based on LEP luminometers, together
with the capability of electron/positron/photon separation.
This new calorimeter concept is designed primarily to maximize the acceptance
for ${e}^{+}e^{-} \to \gamma \gamma$...
We study the quark sector of the universal seesaw model with $SU(2)_L × SU(2)_R × U(1)_{Y'}$ gauge symmetry in the massless limit of the two lightest quark families. This model aims to explain the mass hierarchy of the third family quark by introducing a vector-like quark partner for each quark. In addition to the Standard Model Higgs doublet, we also introduce one right-handed Higgs doublet....
Current collider experiments, such as LHC have been studying the production of the BSM particles and their decay to the Standard Model particles. These searches have placed strong constraints on different BSM models as well as on the mass of BSM particles. The situation demands to look for alternative scenarios. BSM theories such as the Pati Salam Model, Composite Higgs, and others suggest...
In this talk, we will discuss the studies presented in PRX ENERGY 2, 047001, where the carbon impact of the Cool Copper Collider ($C^3$), a proposed electron-positron linear collider operated at 250 and 550 GeV center-of-mass energy, is evaluated. We introduce several strategies to reduce the power needs for $C^3$ without modifications in the ultimate physics reach. We also propose a...
Increasing awareness and action on sustainability efforts for current and future accelerators has led to notable progress in recent years. Higher priority has to be given to environmental sustainability including energy consumption, natural resource use and the environmental impact of effluents. Typically, increased performance - higher beam energies and intensities - of proposed new...
Concrete, the quintessential construction material composed of cement, water, sand, and aggregates, is indispensable for infrastructure and societal advancement. As the threat of climate change looms, the construction industry is striving to reduce the carbon emissions from concrete production. This study offers an in-depth analysis of practical applications and introduces advanced...
R&K, an independent company, has achieved production of 2.3 million 1.9GHz microwave power amplifiers for mobile-comm’s-base-stations and then also supplies wideband power amplifiers for automobile EMC testing for domestic automobile industries. Then 16 years ago, we started new design and producing some hundreds kW RF SSA for accelerator applications instead of Klystron / tube...
The initial design of the capture cavities for the continuous wave (CW) polarized positron beams at Jefferson Lab (Ce+BAF) is presented. A chain of standing wave multi-cell copper cavities inside a solenoid tunnel are selected to bunch/capture positrons. The cavity design strategy is presented to accommodate constrains from the large phase distribution of the incident beams, RF power,...
Invited talk on the electroweak measurements at the LHC and HL-LHC.
The future circular electron-positron collider FCCee is receiving much attention in the context of the FCC Feasibility Study currently in progress in preparation for the next EU strategy update. The most recent status of the R&D of the drift chamber project for the IDEA detector concept is presented. We discuss the physics requirements, the technical solutions chosen to address them, the...
Conventional SRF cavities are used in standing wave regime and are limited by surface fields to ~50 MV/m. In order to overcome this limit, Superconducting Traveling Wave (SCTW) cavity was proposed as it allows to achieve ~1.5 times higher accelerating gradient operating at lower phase advance per cell, thus improving transit time factor. However, power recirculation through a feedback...
This talk covers recent highlights of BSM searches from the CMS experiment and future prospects at HL-LHC.
High power converter positron targets can be designed and assessed thermally with computational fluid dynamics (CFD). I will present the CFD assessments of a high power liquid Xenon (LXe) target and a rotating tungsten target with the ILC time structure for the beam.
While a demonstration of TW resonance excitation in the 3-cell structure in 2K liquid helium had been prepared and carried out at Fermilab in collaboration with Euclid Techlabs, the RF design process of 0.5~1 meter scale TW cavity was begun at Fermilab as the next step of TW development towards an accelerator-scale one. Considering the physical dimensions of existing SRF facilities (for...
Achieving high instantaneous luminosity while managing the beam-induced background (BIB) is critical for the successful operation of any future electron-positron ($e^{+}e^{-}$) collider. In this talk, we will present the first extensive luminosity studies for a proposed linear $e^{+}e^{-}$ collider, the Cool Copper Collider (C$^3$), as discussed in arXiv:2403.07093. We begin with a theoretical...
To achieve target performance of the C3 accelerator, many elements will need to be manufactured, assembled, and aligned in use to very tight tolerances. Testing of accelerating structure manufacturing, alignment, mounting, and liquid nitrogen cooling will be performed at SLAC using an accelerator length of approximately 2 meters. This talk will review progress and plans toward commissioning a...
Pair- and single-production of W bosons provide many opportunities to look for new physics via precision measurements, for instance via scrutinizing the involved triple-gauge vertices or by measuring CKM matrix elements in an environment very complementary to B hadron decays. This contribution presents the ongoing work based on full simulation of the ILD detector concept, exploiting the...
The LUXE experiment is designed to explore the strong-field QED regime in interactions of high-energy electrons from the European XFEL in a powerful laser field. One of the crucial aims of this experiment is to measure the production of electron-positron pairs as a function of the laser field strength where non-perturbative effects are expected to kick in above the Schwinger limit.
For the...
In this paper we report on the design, fabrication, tuning and high-power RF testing of the fundamental accelerating structure for the Cool Copper Collider (CCC). The results presented here cover the temperature range from room temperature to liquid nitrogen boil off: 20oC - 77 K
At room temperature, RT, with a N2 gas purge of 1 atmosphere, the CCC structure was tuned to a resonance...
Several proposals of e+e- colliders with energy recovery
concept have been proposed in the last few years. I shall
discuss about possible upgrade of ILC in the far future
using energy recovery linacs.
Spin-polarized electron photoelectron sources are a critical component of multiple future collider designs. The present state-of-the-art polarized electron photocathode material, negative electron affinity gallium arsenide, has remarkable performance: it possesses high quantum efficiency and can emit beams with a spin polarization exceeding 90% under the right conditions. However, its extreme...
The Future Circular Collider electron-positron (FCCee) feasibility study involves assessing the capabilities and performance of potential detector configurations. This study focuses on the impact of various detector parameters on tracking performance. Specifically, the influence of different geometries, material budgets, and magnetic field strengths on the precision and efficiency of tracking...
Future e$^+$e$^-$ colliders, with their clean environment and triggerless operation, offer a unique opportunity to search for long-lived particles (LLPs). Considered in this contribution are prospects for LLP searches with the International Large Detector (ILD) providing almost continuous tracking in Time Projection Chamber (TPC) as the core of its tracking systems. The ILD has been developed...
Radiative corrections due to initial state radiation in electron-positron
annihilation are calculated within the QED structure function approach. NLO QED parton distribution functions are derived analytically. Results are shown in the next-to-leading logarithmic approximation up to $\mathcal{O}(\alpha^4 L^3)$ order, where $L=\ln(s/m_e^2)$ is the large logarithm. Several mistakes in previous...
As the part of research into the manufacturing methods for SRF cavities used in ILC(International Linear Collider), two 1.3 GHz single-cell cavities have been fabricated by utilizing fine and medium grain size niobium materials, respectively, with the same manufacturing equipment. The fine grain size niobium material typically exhibits a grain size level equivalent to ASTM 5-6, whereas the...
The presentation will report on recent CLIC positron source activities.
The focus will be on flux concentrator developments and beam loading calculations of the capture LINAC.
We will present results from high gradient structure testing of C-band single-cell copper (Cu) and copper silver (CuAg) accelerating structures at 77 K. C-band accelerators have been of particular interest in recent years due to their ability to provide high gradients and transport high charge beams for applications ranging from colliders to medical technologies. These technologies are made...
The future linear and circular electron positron colliders were been proposed as a Higgs and a high luminosity Z factory in last few years. The detector conceptual design of a updated detector consists of a tracking system, which is Time Projection Chamber (TPC) detector as the main track with the high precision (about 100$\mu$m overall drift length at 3T magnetic field) spatial resolution...
Our recent work has shown that a novel, ultra-high granularity,
forward calorimetry concept can enable much more detailed and precise
reconstruction than the compact baseline designs based on LEP luminometers, together
with the capability of electron/positron/photon separation.
In this contribution we will highlight the significantly more precise
measurements of photon four-vectors...
The electron-positron stage of the Future Circular Collider, FCC-ee, is a frontier factory for Higgs, top, electroweak, and flavour physics. It is designed to operate in a 100 km circular tunnel built at CERN, and will serve as the first step towards ≥ 100 TeV proton-proton collisions. In addition to an essential and unique Higgs program, it offers powerful opportunities to discover direct or...
We propose a new renormalization scheme in extended Higgs sectors for the coming new era of the Higgs precise measurements at future lepton colliders. In this new scheme, we use a precisely measured value of the discovered Higgs boson coupling, e.g., hZZ, as an input of the renormalization condition. We demonstrate how the other Higgs boson couplings (e.g., hWW) can be predicted. in this new...
The design of the next generation of linear colliders demands a renewed, high-performance, integrated set of simulation codes. We present the Beam, pLasma & Accelerator Simulation Toolkit (BLAST), which includes legacy accelerator codes such as Impact-T, Impact-Z, Warp and Posinst, as well as a renewed generation of accelerator codes such as ImpactX, WarpX and HiPACE++. The new codes, born out...
In this work, we attempt to classify regions in a multidimensional parameter space according to their importance during a simulation. Considering that the parameter space could be high dimensional and the simulated process could result in arbitrary shapes, we involve a neural network in the process of guessing such shapes without running the full simulation for every point. We illustrate the...
In this talk I will review the models motivating searches for heavy neutral leptons at future e+e- colliders by linking their properties to different frameworks for neutrino mass generation and mixing. Several different regimes of prompt decays vs. long-lived HNLs vs. displaced tracks will be discussed together with their experimental signatures.
Present status and plan on E-driven positron source for ILC will be presented.
This talk might be a introduction to the several related topics by colleagues working on the project.
We study a search for the charged Higgs boson via $e^+e^− \to H^+H^− \to c\bar b\bar cb$ at the 500 GeV ILC. In a general two Higgs doublet model without $Z_2$ symmetry, extra Yukawa couplings $\rho_{tc}$ and $\rho_{tt}$ can drive electroweak baryogenesis, but searches at the HL-LHC may still go empty-handed if the couplings are relatively weak. Taking $m_{H^+} \simeq m_H \simeq$ $m_A\simeq...
The initial proposed design of the Cold Copper Collider (C3) is based on a distributed coupling accelerating (DCA) rf structure where the phase advance between the accelerating standing wave cavities is π. In these cavities the aperture radius is 2.624 mm and the corresponding shunt impedance is 300 MΩ/m with 77K copper walls. We propose a novel DCA rf structure with 3π/4 phase advance between...
The International Linear Collider (ILC) represents the next generation of electron-positron colliders, designed to operate at center-of-mass energies ranging from 250 GeV, with plans to extend up to 1 TeV in the future. This opens up a broad spectrum of possibilities for exploring physics beyond the Standard Model. The ILC requires advanced engineering technology and meticulous design to...
Particle flow plays an important role in precise measurement of Higgs bosons at future lepton colliders such as ILC and FCCee. Various detector concepts are designed to maximize the effect of particle flow to be able to separate each particle s inside jets and improve the resolutions. For the standard particle flow algorithm, PandoraPFA is used for long in ILC studies. It is a multi-step...
We study the CP-even neutral Higgs boson decays h -> c \bar{c}, b \bar{b},
b \bar{s}, \gamma \gamma, g g in the Minimal Supersymmetric Standard Model (MSSM)
with general quark flavor violation (QFV) due to squark generation mixings,
identifying the h as the Higgs boson with a mass of 125 GeV. We compute the widths
of the h decays to c \bar c, b \bar b, b \bar s (s \bar b) at full...
The International Linear Collider (ILC) is among the most mature designs for a next-generation linear electron-positron collider. Plasma-based accelerators have also been proposed to reach the 10 TeV COM level further in the future. A key challenge in these types of machines is preserving the luminosity at the target value, mitigating the potentially detrimental effects of disruption,...
I will report on a comparison of beam-strahlung backgrounds at the ILC and FCCee, with an emphasis on the TPC and Vertex detector. The different MDI designs and beam timing structures at the two colliders have some dramatic effects on detector backgrounds.
KEK is now constructing a cryomodule for 1.3 GHz TESLA cavities. Design of this cryomodule and the status of construction will be presented in this talk.
The majority of Monte-Carlo (MC) simulation campaigns for future Higgs factories has so far been based on the leading-order (LO) matrix elements provided by Whizard 1.95,
followed by parton shower and hadronization in Pythia6,
using the tune of the OPAL experiment at LEP.
In this contribution, we test the next-to-leading-order (NLO) mode of Whizard.
NLO events of $e^+e^-\to q\bar{q}$...
Beam-beam interactions constitute an important source of background at any electron-positron ($e^{+}e^{-}$) collider, generating the so-called beam-induced background (BIB), with important implications for the design and optimization of detectors at these machines and, ultimately, their physics reach. In this talk, we will present the latest results on the evaluation of the BIB at the Cool...
Although the Higgs boson has been discovered, the couplings with the Higgs boson have room for deviation from the Standard Model (SM) prediction. Each extended Higgs model is characterized by its Higgs potential. Nearly aligned models where the shape of the Higgs potential is described by one classical field include the classical scale invariance model (CSI), the pseudo-Nambu-Goldstone model,...
We present the design of an APS cavity for the capture linac of the ILC E-driven positron source. It is required to accelerate a high-current multi-bunch positron beam in this positron source. Therefore, beam loading compensation and managing the heat load exceeding 10 kW due to electromagnetic showers generated at the target are important issues. We have designed a 21-cell APS accelerator,...
The origins of tiny neutrino mass, dark matter and baryon asymmetry of the Universe remain big mysteries in particle physics. To explain all these phenomena, a new physics model with a Higgs sector extended at the TeV scale was proposed by Aoki, Kanemura and Seto. However, CPV phases were neglected for simplicity, and the baryon number production via electroweak baryogenesis had not been...
The Low-Level RF (LLRF) control circuits of linear accelerators (LINACs) are conventionally realized with heterodyne based architectures, which have analog RF mixers for up and down conversion with discrete data converters. We have developed a new LLRF platform for C band linear accelerator based on the Frequency System-on-Chip (RFSoC) device from AMD Xilinx. The integrated data converters in...
Robotic dust-free clean assembly is currently attracting worldwide attention, and KEK has purchased a Fanuc CRX-20iA/L and is conducting R&D for its application to ILC type string assembly. The status of KEK's activity on the robotics will be presented in the presentation.
https://agenda.linearcollider.org/event/10384/
Some types of LLPs can be indentified by kinked tracks. The Time Projection Chamber (TPC) being designed for ILD at ILC provides almost continuous tracking. This should give excellent potential for kink finding. I will review the current kink finder algorithm, and present a new kink finding method.
Many new physics scenarios render a low mass scalar candidate. I will briefly discuss the current status of such models, and give an short overview on current studies for such models at Higgs factories, including efforts within the ongoing ECFA effort.
The proposed LUXE experiment (Laser Und XFEL Experiment) at DESY, Hamburg, using the 16.5 GeV electron beam extracted from the European XFEL, aims to study collisions between high-intensity laser pulses and high-energy electron or secondary photon beams (unique feature at LUXE). This will elucidate quantum electrodynamics (QED) at the strong-field frontier, where the electromagnetic field of...
Accurate and fully differential predictions are crucial inputs for the precise experimental analyses at linear colliders and are typically provided by parton shower Monte Carlo programs. The event generator Sherpa with its focus on the inclusion of higher-order EW and QCD effects is available in a new version 3.0 this year and we will summarise its new features in particular where they relate...
The high luminosity specifications for future linear colliders, such as the Compact Linear Collider (CLIC), require extremely small vertical beam emittance at the interaction point. Achieving this relies on minimizing the emittance growth in the collider sub-systems. One major source of emittance growth is in the Main Linac, mainly due to misaligned quadrupoles and accelerating structures. The...
Several searches for Higgs bosons below 125 GeV show an excess around $m_\phi = 95.4$ GeV. These include in particular $gg \to \phi \to \gamma\gamma$ at CMS and ATLAS and $e^+e^- \to Z^* \to Z (\phi \to b \bar b)$ at LEP. We discuss BSM Higgs sectors that can accommodate these excesses. We demonstrate that such a light Higgs boson can be analyzed in detail at $e^+e^-$ colliders.
Physics studies for future colliders require a reliable software environment. For many years this has been delivered by iLCSoft for the linear collider communities. In the last five years a common effort of several communities, including ILC, CLIC, FCC and CEPC, have collaborated on the Key4hep software stack to deliver a common software stack for all future collider communities. This software...
Research and development on novel structures is at the core of advancing structure wakefield acceleration (SWFA), and is critical to future AAC-based linear colliders. In this talk, I will present recent progress on the R&D of advanced radiofrequency (RF) structures for Structure Wakefield Acceleration, metamaterial structures, and sub-terahertz structures. The experiments were performed at...
We give a status report on new developments within the WHIZARD event generator. Important new features comprise NLO electroweak automation (incl. extension to BSM processes like SMEFT), loop-induced processes and new developments in the UFO interface. We highlight work in progress and further plans, such as the implementation of electroweak PDFs, photon radiation, the exclusive top threshold...
For C^3, approximately 2000 accelerator sub units must be positioned, within 10 um transversal, on a 2.3 km long straight line for each linac.
In the Rasnik alignment system, light from a point-like monochromatic source falls on a zone plate, forming a Fraunhofer diffraction pattern on an image pixel sensor. The alignment of three objects can be obtained by analyzing the position of the...
In the recent years a large set of indications for BSM scalars has been observed in LHC data. After a brief description of the most significant indications, this presentation intends to give a consistent interpretation in terms of a generalised Georgi Machacek model which predicts a doubly charged scalar indicated by ATLAS data. Consequences for currently planned e+e- colliders will be...
The Compact Linear Collider (CLIC) proposes a linear accelerator system aimed at colliding electrons and positrons at energies up to 3 TeV. To explore novel physics and enhance competitiveness with other collider projects, CLIC is considering increasing the center-of-mass energy to 7 TeV. A crucial component of the CLIC infrastructure is the Beam Delivery System (BDS), responsible for...
The identification of certain charged hadron species, e.g. Kaons and protons, plays an important role in many physics analyses. Time-of-flight measurements can contribute to identifying these particles if both the length of the flight path as well as the time of arrival can be determined with sufficient precision. This contribution will discuss the recent progress on both aspects, and in...
Our research group, composed of Pohang Accelerator Laboratory, Korea University, Northen Illinois Universiy, and Argonne Wakefield Accelerator Facility, is researching on wakefields generated in corrugated structures. Main goal of our research is to make several applications such as a THz source in the GW scale, wakefield accelerators and IR-FELs.
As a first step, we designed and fabricated...
During the development of the NLC/JLC normal conducting X-band linear colliders, it became clear that the RF power flow in traveling wave accelerating structures correlates more with the RF breakdown rate than with the peak electric fields. To mitigate the adverse effects of RF power flow, low group velocity and standing wave accelerating structures optimized for lower RF input power have been...
The physics program of the Higgs factory will focus on measurements of the 125 GeV Higgs boson, with the Higgs-strahlung process being the dominant production channel at 250 GeV. However, production of extra light scalars is still not excluded by the existing experimental data, provided their coupling to the gauge bosons is sufficiently suppressed. Fermion couplings of such a scalar could also...
Parton showers are important tools in the event generation chain for future collider. Recently, their formally achieved accuracy has been under extended scrutiny. In this talk I will present a novel take on dipole parton showers [1], resulting in the design of a new parton shower called Alaric that is implemented in the Sherpa framework. I will discuss its resummation properties and show...
The next generation electron-positron collider is crucial for precision measurements of the Higgs boson and exploring new physics beyond the Standard Model. Currently, the scale and cost of linear or circular colliders based on traditional radio-frequency accelerators are enormous to meet the standards for a Higgs factory. Advanced accelerator concepts such as the plasma wakefield accelerator...
A feasibility study is conducted to search for an exotic decay of the Standard Model Higgs boson decaying into a pair of light pseudoscalar bosons in the Cool Copper Collider (C3) experiment. The Higgs boson is produced in association with a Z boson and the decay products consist of a pair of b-quarks and tau leptons. The pseudoscalar bosons are probed over a mass range spanning from 20 to 60...
Since 2017, CEA has been developing the use of collaborative robots (cobot) to carry out the steps required to assemble superconducting cavities strings. This development is based on two main objectives. The first is to reduce the tediousness for operators of certain stages of component cleaning by blowing, so that they can focus on higher value-added tasks. The second is to improve assembly...
The Hybrid Asymmetric Linear Higgs Factory (HALHF) proposes a shorter and cheaper alternative for a future Higgs factory. The design includes a 500 GeV electron beam accelerated by an electron-driven plasma wake-field, and a conventionally-accelerated 31 GeV positron beam. Assuming plasma acceleration R&D challenges are solved in a timely manner, the asymmetry of the collisions brings...
To explain the baryon asymmetry in the universe a First Order Electroweak Phase Transition (FOEWPT) in the early universe is favored. This requires a BSM Higgs sector, which introduces additional Higgs bosons as well as the corresponding additional trilinear Higgs couplings (THCs). Taking the 2HDM as a concrete example, we discuss how such BSM THCs might be accessible at the ILC/CLIC via...
Future colliders will require injector linacs to accelerate large electron bunches over a wide range of energies. For example the Electron Ion Collider requires a pre-injector linac from 4 MeV up to 400 MeV over 35 m. Currently this linac is being designed with 3 m long traveling wave structures, which provide a gradient of 16 MV/m. We propose the use of a 1 m distributed coupling design as a...
We report on cold test measurements of an X-band (11.424 GHz) accelerator to provide electron beams for Very High Energy Electron therapy of cancer. The standing wave linac is designed with a 135° phase advance utilizing distributed coupling through four parallel manifolds. The accelerator is expected to reach a 100 MeV/m accelerating gradient in a one-meter structure using only 19 MW when...
High density electromagnetic sandwich calorimeters with high readout granularity are considered for many future collider and fix-targer experiments. Optimization of the calorimeter structure from the point of view of the electromagnetic shower energy, position and direction measurement is one of the key aspects of the design. However, mostly uniform sampling structures were considered so far....
State of the art in low-emittance storage rings will be presented.
The Mainz Energy-recovering Superconducting Accelerator (MESA), an energy-recovering (ER) LINAC, is currently under construction at the Institute for Nuclear physics at the Johannes Gutenberg-Universität Mainz, Germany. In the ER operation mode, continuous wave (CW) beam is accelerated from 5 MeV up to 105 MeV. The energy gain of the beam is provided through 2 enhanced ELBE-type cryomodules...
The CLIC positron source was simulated and optimised. A new baseline was proposed with a single amorphous tungsten target and a flux concentrator based matching device. Misalignments of the beamline are studied. Alternative scenarios with higher positron yields are also studied.
We discuss the experimental prospects for measuring differential observables in b-quark and c-quark pair production at the International Linear Collider (ILC) baseline energies, 250 and 500 GeV. The study is based on full simulation and reconstruction of the International Large Detector (ILD) concept. Two gauge-Higgs unification models predicting new high-mass resonances beyond the Standard...
The present design of ILC DR will be presented.
Following the mid-term review in 2023, the Future Circular Collider (FCC) feasibility study at CERN continues towards the European Strategy for Particle Physics 2025. This talk will cover the main updates, current progress of the civil engineering design and the status of the geotechnical site investigations.
Research and development on high-Q cavities requires extensive experimental campaigns to understand the origin of possible performance limitations and then to study the effect of more advanced surface treatments on the physical mechanisms governing such a high-Q operating regime.
From the experimental point of view, significant effort must be made to avoid flux trapping, either by canceling...
The beam produced in the target of the ILC positron source is highly divergent and therefore requires immediate optical matching, conventionally performed by some kind of solenoid arrangement.
Recently, the use of a plasma lens has been considered as an alternative with hopes to increase number of positrons available for the downstream acceleration. Previous simulations have indicated that a...
High-energy particle accelerators are crucial to the next big discovery in particle physics. To reduce the size and cost of particle accelerators, increasing the accelerating gradient (energy gain per unit length for the particle beam) is of critical importance. Advanced accelerator concepts (AACs) hold the promise of revolutionary future particle colliders with dramatically higher gradients...
Unprecedented precision is needed to address the Higgs physics with detectors at future e+e- colliders. Linear colliders offer low duty cycles and low backgrounds, that greatly assist achieving these goals. The SiD Collaboration is developing an application of Monolithic Active Pixel Sensor (MAPS) technology for tracking and electromagnetic calorimetry (ECal). This technology offers high...
Invited talks on the ECFA Topic: Higgs self-coupling
We present SMEFiT3.0, an updated global SMEFT analysis of Higgs, top quark, and diboson production data from the LHC complemented by electroweak precision observables (EWPOs) from LEP and SLD. We consider recent inclusive and differential measurements from the LHC Run II and estimate the impact of HL-LHC measurements on the SMEFT parameter space when added on top of SMEFiT3.0, through...
The current status and future development plans of ILC BDS will be explained.
The machine-detector interface (MDI) issues are one of the most complicate and challenging topics at the Circular Electron Positron Collider (CEPC). Comprehensive understandings of the MDI issues are decisive for achieving the optimal overall performance of the accelerator and detector. The machine will operate at different beam energies, therefore, a flexible interaction region design will be...
Possibility that the ILD detector might be realized at a future e+e- collider calls for quantification of precision of the integrated luminosity measurement, assuming here the ILC operating scenarios at the Z-pole, 250 GeV, 500 GeV and 1 TeV center-of-mass energies. This is the first comprehensive study of the systematic uncertainties in integrated luminosity measurement at ILC, rising from...
The acceleration gradient is a critical parameter affecting the feasibility and cost of large-scale particle accelerators such as normal conducting linear colliders. The main obstacle to increasing the acceleration gradient or improving the reliability of a linear accelerator at a certain gradient is vacuum RF breakdown. To understand the basic physics of the RF breakdown in cavities suitable...
The quest for novel technologies in the ever-evolving landscape of scientific exploration has led to the investigation of plasma lensing as a potential solution for optical matching devices at positron sources. This research becomes increasingly significant as the need for higher data output demands innovative concepts to increase positron yield and therefore luminosity. Our initial...
Status and plans of CLIC BDS will be presented.
MDI at gamma gamma collider
ATF2 incoherent Cherenkov radiation monitor status and plans will be presented.
The precise measurement of the 125 GeV Higgs boson is one of the powerful ways to probe new physics. In particular, it is known that a large deviation from the SM predictions can appear in the di-Higgs production process e.g., via new physics effects of the triple Higgs boson coupling.
In this talk, we discuss the theoretical behavior of the di-Higgs production cross section in the composite...
The simulation of particle generation, their interaction with detector materials, and the resulting detector response has become increasingly crucial in recent experiments. Semiconductor+W calorimeters, known for their high compactness and granularity, are integral components of proposed detector designs for upcoming Higgs Factories as well as experiments targeting strong-field-QED (LUXE) or...
ATF2 BPMs status and plans will be presented.
Invited talk on the status of the theory of the Higgs self coupling
The standard Model (SM) is the best currently experimentally tested theory of fundamental particles and their interactions. The discovery of Higgs boson completes the particle spectrum of SM and now the particle physics have officially entered the era of precision measurement. While the SM enjoys robust experimental verification, it falls short in explaining phenomena like the naturalness...
Studies and R&D on the high-intensity positron source for the FCC-ee are ongoing as part of the FCC Feasibility Study. The current baseline design relies on a conventional positron production scheme. Recently, a feasibility study on using a superconducting (SC) solenoid for positron capture has begun, with a design based on High-Temperature Superconductor (HTS) technology currently adopted for...
For future particle colliders, cavity Beam Position Monitors (cBPMs) have emerged as the optimal solution for precisely measuring the beam position, crucial for guiding and stabilizing high-energy beams with nanometer precision, thus enhancing luminosity at the interaction point. Resonant BPMs operate under the principle of detection of specific field configurations (resonant modes) induced by...
For future particle colliders, cavity Beam Position Monitors (cBPMs) have emerged as the optimal solution for precisely measuring the beam position, crucial for guiding and stabilizing high-energy beams with nanometer precision, thus enhancing luminosity at the interaction point. Resonant BPMs operate under the principle of detection of specific field configurations (resonant modes) induced by...
