H. Abramowicz, M. Altarelli, R. Aßmann, T. Behnke, Y. Benhammou, O. Borysov, M. Borysova, R. Brinkmann, F. Burkart, K. Büßer, O. Davidi, W. Decking, N. Elkina, … 展开作者
H. Abramowicz, M. Altarelli, R. Aßmann, T. Behnke, Y. Benhammou, O. Borysov, M. Borysova, R. Brinkmann, F. Burkart, K. Büßer, O. Davidi, W. Decking, N. Elkina, H. Harsh, A. Hartin, I. Hartl, B. Heinemann, T. Heinzl, N. TalHod, M. Hoffmann, A. Ilderton, B. King, A. Levy, J. List, A. R. Maier, E. Negodin, G. Perez, I. Pomerantz, A. Ringwald, C. Rödel, M. Saimpert, F. Salgado, G. Sarri, I. Savoray, T. Teter, M. Wing, M. Zepf
This Letter of Intent describes LUXE (Laser Und XFEL Experiment), an experiment that aims to use the high-quality and high-energy electron beam of the European XFEL and a powerful laser. The scientific objective of the experiment is to study quantum electrodynamics processes in the regime of strong fields. High-energy electrons, accelerated by the European XFEL linear accelerator, and high-energy photons, produced via Bremsstrahlung of those beam electrons, colliding with a laser beam shall experience an electric field up to three times larger than the Schwinger critical field (the field at which the vacuum itself is expected to become unstable and spark with spontaneous creation of electron-positron pairs) and access a new regime of quantum physics. The processes to be investigated, which include nonlinear Compton scattering and nonlinear Breit-Wheeler pair production, are relevant to a variety of phenomena in Nature, e.g. in the areas of astrophysics and collider physics and complement recent results in atomic physics. The setup requires in particular the extraction of a minute fraction of the electron bunches from the European XFEL accelerator, the installation of a powerful laser with sophisticated diagnostics, and an array of precision detectors optimised to measure electrons, positrons and photons. Physics sensitivity projections based on simulations are also provided.
We propose a new experiment sensitive to the detection of millicharged particles produced at the $30$ GeV proton fixed-target collisions at J-PARC. The potential site for the experiment is B2 of the Neutrino Monitor building, $280$ m away from the target. With $\textrm{N}_\textrm{POT}=10^{22}$, the experiment can provide sensitivity to particles with electric charge $3\times10^{-4}\,e$ for mass less than $0.2$ $\textrm{GeV}/\textrm{c}^2$ and $1.5\times10^{-3}\,e$ for mass less than $1.6$ $\textrm{GeV}/\textrm{c}^2$. This brings a substantial extension to the current constraints on the charge a…
In this LOI we propose a dedicated experiment that would detect "milli-charged" particles produced by pp collisions at LHC Point 5. The experiment would be installed during LS2 in the vestigial drainage gallery above UXC and would not interfere with CMS operations. With 300 fb$^{-1}$ of integrated luminosity, sensitivity to a particle with charge $\mathcal{O}(10^{-3})~e$ can be achieved for masses of $\mathcal{O}(1)$ GeV, and charge $\mathcal{O}(10^{-2})~e$ for masses of $\mathcal{O}(10)$ GeV, greatly extending the parameter space explored for particles with small charge and masses above 100 M…
This document describes the plans of the ALICE Collaboration for a major upgrade of its detector, referred to as ALICE 3, which is proposed for physics data-taking in the LHC Run 5 and beyond. ALICE 3 will enable an extensive programme to fully exploit the LHC for the study of the properties of strongly interacting matter with high-energy nuclear collisions. The proposed detector layout, based on advanced silicon sensors, features superb pointing resolution, excellent tracking and particle identification over a large acceptance and high readout-rate capabilities. This document discusses the pr…
With the planned turn-on of the PIP-II 800 MeV superconducting proton linac, Fermilab will potentially become the world's best laboratory at which to carry out fundamental muon measurements, sensitive searches for symmetry violation, and precision tests of theory. In preparation, we propose to develop the techniques that will be needed. An R&D and physics program is proposed at the Fermilab MeV Test Area to use the existing 400 MeV Linac to demonstrate the efficient production of a slow muonium beam using $μ^+$ stopped in a ~100-$μ$m-thick layer of superfluid helium, and to use that beam to me…
Jinping Neutrino Experiment (Jinping) is proposed to significantly improve measurements on solar neutrinos and geoneutrinos in China Jinping Laboratory - a lab with a number of unparalleled features, thickest overburden, lowest reactor neutrino background, etc., which identify it as the world-best low-energy neutrino laboratory. The proposed experiment will have target mass of 4 kilotons of liquid scintillator or water-based liquid scintillator, with a fiducial mass of 2 kilotons for neutrino-electron scattering events and 3 kilotons for inverse-beta interaction events. A number of initial sen…
In this Letter of Intent (LOI) we propose the construction of MATHUSLA (MAssive Timing Hodoscope for Ultra-Stable neutraL pArticles), a dedicated large-volume displaced vertex detector for the HL-LHC on the surface above ATLAS or CMS. Such a detector, which can be built using existing technologies with a reasonable budget in time for the HL-LHC upgrade, could search for neutral long-lived particles (LLPs) with up to several orders of magnitude better sensitivity than ATLAS or CMS, while also acting as a cutting-edge cosmic ray telescope at CERN to explore many open questions in cosmic ray and …
FASER is a proposed small and inexpensive experiment designed to search for light, weakly-interacting particles at the LHC. Such particles are dominantly produced along the beam collision axis and may be long-lived, traveling hundreds of meters before decaying. To exploit both of these properties, FASER is to be located along the beam collision axis, 480 m downstream from the ATLAS interaction point, in the unused service tunnel TI18. We propose that FASER be installed in TI18 in Long Shutdown 2 in time to collect data from 2021-23 during Run 3 of the 14 TeV LHC. FASER will detect new particle…
The Precision IceCube Next Generation Upgrade (PINGU) is a proposed low-energy in-fill array of the IceCube Neutrino Observatory. Leveraging technology proven with IceCube, PINGU will feature the world's largest effective volume for neutrinos at an energy threshold of a few GeV, improving the sensitivity to several aspects of neutrino oscillation physics at modest cost. With its unprecedented statistical sample of low-energy atmospheric neutrinos, PINGU will have highly competitive sensitivity to $ν_μ$ disappearance, the $θ_{23}$ octant, and maximal mixing, will make the world's best $ν_τ$ app…
We report on recent progress in the design of the proposed MATHUSLA Long Lived Particle (LLP) detector for the HL-LHC, updating the information in the original Letter of Intent (LoI), see CDS:LHCC-I-031, arXiv:1811.00927. A suitable site has been identified at LHC Point 5 that is closer to the CMS Interaction Point (IP) than assumed in the LoI. The decay volume has been increased from 20 m to 25 m in height. Engineering studies have been made in order to locate much of the decay volume below ground, bringing the detector even closer to the IP. With these changes, a 100 m x 100 m detector has t…
We propose a new fixed-target experiment for the study of electromagnetic and hard probes of the Quark-Gluon Plasma (QGP) in heavy-ion collisions at the CERN SPS. The experiment aims at performing measurements of the dimuon spectrum from threshold up to the charmonium region, and of hadronic decays of charm and strange hadrons. It is based on a muon spectrometer, which includes a toroidal magnet and six planes of tracking detectors, coupled to a vertex spectrometer, equipped with Si MAPS immersed in a dipole field. High luminosity is an essential requirement for the experiment, with the goal o…
Following a Letter of Intent submitted to PAC43 at JLab in this talk we discuss the possibility to create a secondary K0_L beam in Hall-D to be used with GlueX detector for spectroscopy of excited hyperons.
Letter Of Intent for a future $μ^+ \to \mathrm{e}^+ γ$ experiment at the High Intensity Muon Beam facility at PSI
INFN Sezione di Pavia（意大利国家核物理研究所帕维亚分部）；ICEPP, The University of Tokyo（东京大学宇宙线地球元素起源研究中心）；INFN Sezione di Roma（意大利国家核物理研究所罗马分部）；Oliver Lodge Laboratory, University of Liverpool（利物浦大学奥利弗·洛奇实验室）；INFN Sezione di Pisa（意大利国家核物理研究所比萨分部）；Department of Physics, University of Oxford（牛津大学物理系）；CERN（欧洲核子研究组织）；Institut de Physique des deux Infinis de Lyon（里昂两无穷大物理研究所）；INFN Sezione di Genova（意大利国家核物理研究所热那亚分部）；INFN Sezione di Napoli（意大利国家核物理研究所那不勒斯分部）；Department of Physics and Astronomy, University College London（伦敦大学学院物理与天文系）；PSI Center for Neutron and Muon Sciences（保罗谢勒研究所中子与μ子科学中心）
The main objectives of the KM3NeT Collaboration are i) the discovery and subsequent observation of high-energy neutrino sources in the Universe and ii) the determination of the mass hierarchy of neutrinos. These objectives are strongly motivated by two recent important discoveries, namely: 1) The high-energy astrophysical neutrino signal reported by IceCube and 2) the sizable contribution of electron neutrinos to the third neutrino mass eigenstate as reported by Daya Bay, Reno and others. To meet these objectives, the KM3NeT Collaboration plans to build a new Research Infrastructure consisting…
This letter of intent proposes an experiment to search for an electric dipole moment of the muon based on the frozen-spin technique. We intend to exploit the high electric field, $E=1{\rm GV/m}$, experienced in the rest frame of the muon with a momentum of $p=125 {\rm MeV/}c$ when passing through a large magnetic field of $|\vec{B}|=3{\rm T}$. Current muon fluxes at the $μ$E1 beam line permit an improved search with a sensitivity of $σ(d_μ)\leq 6\times10^{-23}e{\rm cm}$, about three orders of magnitude more sensitivity than for the current upper limit of $|d_μ|\leq1.8\times10^{-19}e{\rm cm}$\,…
