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arXiv · 2503.19880

HALHF: a hybrid, asymmetric, linear Higgs factory using plasma- and RF-based acceleration

Erik Adli·Joshua Appleby·Timothy L. Barklow·Marica Biagini·Jonas Björklund Svensson·Mikael Berggren·Simone Bettoni·Stewart Boogert·Philip Burrows·Allen Caldwell·Jian Bin Ben Chen·Vera Cilento·Laura Corner·Richard D'Arcy·Steffen Doebert·Wang Dou·Pierre Drobniak·Calvin Dyson·Sinead Farrington·John Farmer·Angeles Faus-Golfe·Manuel Formela·Arianne Formenti·Louis Forrester·Brian Foster·Jie Gao·Spencer Gessner·Niclas Hamann·Alexander Harrison·Mark J. Hogan·Eir Eline Hørlyk·Daniel Kalvik·Antoine Laudrain·Reme Lehe·Wim Leemans·Carl A. Lindstrøm·Benno List·Jenny List·Xueying Lu·Edward Mactavish·Vasyl Maslov·Emilio Nanni·John Osborne·Jens Osterhoff·Felipe Peña·Gudrid Moortgat Pick·Kristjan Põder·Jurgen Reuter·Dmitrii Samoilenko·Nela Sedlackova·Andrei Seryi·Kyrre Sjobak·Terry Sloan·Steinar Stapnes·Rogelio Tomas Garcia·Maxim Titov·Malte Trautwein·Maxence Thévenet·Nicholas J. Walker·Marc Wenskat·Matthew Wing·Jonathan Wood
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Abstract

HALHF is a hybrid linear collider that uses electron-driven plasma-wakefield acceleration to accelerate electrons to high energy while using radio-frequency cavity technology to accelerate positrons. The most cost-effective solution collides low-energy positrons with high-energy electrons, producing a boost to the final state in the electron direction with $\gamma= 1.67$. The current HALHF baseline design produces a luminosity comparable to that of the baseline ILC but with a greatly reduced construction and carbon footprint and hence much lower cost than the mature linear-collider designs ILC and CLIC. Costs for HALHF are evaluated, together with that for the approximate 15-year R\&D programme necessary to realise HALHF. Time scales and cost for the R\&D are estimated. Upgrade paths for HALHF technology from a 250~GeV Higgs factory, through 380 and 550~GeV, up to 10~TeV are sketched.

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Erik Adli, Joshua Appleby, Timothy L. Barklow, Marica Biagini, Jonas Björklund Svensson, Mikael Berggren, Simone Bettoni, Stewart Boogert, Philip Burrows, Allen Caldwell, Jian Bin Ben Chen, Vera Cilento, Laura Corner, Richard D'Arcy, Steffen Doebert, Wang Dou, Pierre Drobniak, Calvin Dyson, Sinead Farrington, John Farmer, Angeles Faus-Golfe, Manuel Formela, Arianne Formenti, Louis Forrester, Brian Foster, Jie Gao, Spencer Gessner, Niclas Hamann, Alexander Harrison, Mark J. Hogan, Eir Eline Hørlyk, Daniel Kalvik, Antoine Laudrain, Reme Lehe, Wim Leemans, Carl A. Lindstrøm, Benno List, Jenny List, Xueying Lu, Edward Mactavish, Vasyl Maslov, Emilio Nanni, John Osborne, Jens Osterhoff, Felipe Peña, Gudrid Moortgat Pick, Kristjan Põder, Jurgen Reuter, Dmitrii Samoilenko, Nela Sedlackova, Andrei Seryi, Kyrre Sjobak, Terry Sloan, Steinar Stapnes, Rogelio Tomas Garcia, Maxim Titov, Malte Trautwein, Maxence Thévenet, Nicholas J. Walker, Marc Wenskat, Matthew Wing, Jonathan Wood. 2025-03-25. HALHF: a hybrid, asymmetric, linear Higgs factory using plasma- and RF-based acceleration. https://arxiv.org/abs/2503.19880

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