Strong field QED is an active research frontier. The investigation of fundamental phenomena such as pair creation, photon-photon and photon-electron interactions in the nonlinear QED regime are a formidable challenge -- both experimentally and theoretically. Several experiments around the world are being planned or in preparation to probe this strong field regime. LUXE (Laser Und XFEL Experiment) is an experimental platform which envisages the collision of the high quality 16.5 GeV electron beam from the European XFEL accelerator with a 100 TW class high power laser. One of the unique features of LUXE is to measure the key observables such as pair rates ($e^+e^-$) with unprecedented accuracy in the characterization of both beams together with ample statistics. The state-of-art detector technologies for high energy particle and photon detection enable percent level precision. The state-of-art high power lasers offer high quality laser beams, however, the residual shot-to-shot fluctuations coupled with the large nonlinearity of the processes under investigation form a particular challenge. An uncertainty of 5 percent on the absolute laser intensity already leads to a very large ( about 40 percent) uncertainty in the pair rate. Hence it becomes essential to control the laser parameters precisely. To mitigate this issue a full suite of laser diagnostics is being currently developed at the JETI40 laser in Jena with the aim of tagging the shot intensity to less than 1 percent. In this presentation, details of the laser and the diagnostics suit for the single shot tagging of all the laser parameters will be presented. Moreover, results from an ongoing campaign to properly relay image the beam without significant distortion of the laser beam parameters for post-diagnosis will be discussed.
Laser Und XFEL Experiment (LUXE), is a new High Energy and Laser Physics experiment planned to be installed in DESY. It will study the interactions of a very-intense Laser beam with the high-energy, high-quality electron beams from the European XFEL accelerator, to measure characteristics of non-perturbative quantum electrodynamics.
The LUXE experiment (Laser Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL. LUXE is intended to study collisions between a high-intensity optical laser and up to 16.5 GeV electrons from the Eu.XFEL electron beam, or, alternatively, high-energy secondary photons. The physics objective of LUXE are processes of Quantum Electrodynamics (QED) at the strong-field frontier, where QED is non-perturbative. This manifests itself in the creation of physical electron-positron pairs from the QED vacuum. LUXE intends to measure the positron p…
The LUXE experiment (Laser Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL. At LUXE, the aim is to study collisions between a high-intensity optical laser and up to $16.5\,$GeV electrons from the Eu.XFEL electron beam, or, alternatively, high-energy secondary photons. The physics objectives of LUXE are to measure processes of Quantum Electrodynamics (QED) at the strong-field frontier, where QED is non-perturbative. This manifests itself in the creation of physical electron-positron pairs from the QED vacuum. LUXE intends to meas…
The LUXE experiment (LASER Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL. LUXE is intended to study collisions between a high-intensity optical laser and 16.5 GeV electrons from the XFEL electron beam, as well as collisions between the optical LASER and high-energy secondary photons. The physics objective of LUXE are processes of Quantum Electrodynamics (QED) at the strong-field frontier, where the electromagnetic field of the laser is above the Schwinger limit. In this regime, QED is non-perturbative. This manifests itself in…
LUXE (Laser Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL. LUXE is intended to study collisions between a high-intensity optical laser and 16.5 GeV electrons from the XFEL electron beam, as well as collisions between the optical laser and high-energy secondary photons. The physics objective of LUXE are processes of quantum electrodynamics (QED) at the strong-field frontier, where the electromagnetic field of the laser is above the Schwinger limit. In this regime, QED is non-perturbative. This manifests itself in the creation o…
The LUXE experiment (Laser Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL (Eu.XFEL). LUXE is intended to study collisions between a high-intensity optical laser and up to 16.5 GeV electrons from the Eu.XFEL electron beam, or, alternatively, high-energy secondary photons. The physics objective of LUXE are processes of Quantum Electrodynamics (QED) at the strong-field frontier, where QED is non-perturbative. The design of the experimental setup and the different detectors are presented.
The FCAL collaboration is preparing large-scale prototypes of special calorimeters to be used in the very forward region at future electron-positron colliders. Two compact calorimeters are foreseen, LumiCal and BeamCal, designed as sandwich calorimeters with very thin sensor planes to keep the Molière radius small. Silicon sensor prototypes and dedicated FE ASICs have been developed and produced for LumiCal. The ASICs have been designed to cope with the timing and dynamic range requirements. The electromagnetic calorimeters of the LUXE experiment are based on a similar technology to that devel…
The LUXE experiment aims at studying strong-field QED in electron-laser and photon-laser interactions, with the $16.5$ GeV electron beam of the European XFEL and a laser beam with power of up to $350$ TW. The strong-field QED processes are expected to have production rates ranging from $10^{-3}$ to $10^9$ per $10$ Hz bunch crossing. Additionally, these measurements must be performed in a low-energy, high-radiation background. The LUXE experiment will utilise various detector technologies to overcome these challenges.
The LUXE experiment, currently in design and planning, aims to perform analyses of strong-field quantum electrodynamics interactions by colliding the high-quality high-energy EU.XFEL electron beam with a powerful laser. With the ability to collide laser pulses with bunches of $1.5 \times 10^9$ electrons / $1 \times 10^8$ photons at 1Hz, this high-statistics environment presents an opportunity to probe rare interactions in a new parameter space of a novel regime. To do this requires a unique suite of detectors to measure three types of particles, at highly varying fluxes dependent on laser inte…
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 wh…
The LUXE experiment aims at studying high-field QED in electron-laser and photon-laser interactions, with the 16.5 GeV electron beam of the European XFEL and a laser beam with power of up to 350 TW. The experiment will measure the spectra of electrons and photons in non-linear Compton scattering where production rates in excess of $10^9$ are expected per 1 Hz bunch crossing. At the same time positrons from pair creation in either the two-step trident process or the Breit--Wheeler process will be measured, where the expected rates range from $10^{-3}$ to $10^4$ per bunch crossing, depending on …
The LUXE experiment aims at studying high-field QED in electron-laser and photon-laser interactions, with the 16.5 GeV electron beam of the European XFEL and a laser beam with power of up to 350 TW. The experiment will measure the spectra of electrons, positrons and photons in expected ranges of 10$^{-3}$ to 10$^9$ per 1 Hz bunch crossing, depending on the laser power and focus. These measurements have to be performed in the presence of low-energy high radiation-background. To meet these challenges, for high-rate electron and photon fluxes, the experiment will use Cherenkov radiation detectors…
The LUXE experiment aims at studying high-field QED in electron-laser and photon-laser interactions, with the 16.5 GeV electron beam of the European XFEL and a laser beam with power of up to 350 TW. The experiment will measure the spectra of electrons and photons in non-linear Compton scattering where production rates in excess of $10^9$ are expected per 1 Hz bunch crossing. At the same time positrons from pair creation in either the two-step trident process or the Breit-Wheeler process will be measured, where the expected rates range from $10^{-3}$ to $10^3$ per bunch crossing, depending on t…
LUXE (Laser Und XFEL Experiment) is a proposed experiment at DESY which will study Quantum Electrodynamics (QED) in the strong-field regime, where QED becomes non-perturbative. Measuring the rate of created electron-positron pairs using a silicon pixel tracking detector is an essential ingredient to study this regime. Precision tracking of positrons traversing the four layers of the tracking detector becomes very challenging at high laser intensities due to the high rates, which can be computationally expensive for classical computers. In this work, we update our previous study of the potentia…
A high-flux electron detection system to measure non-linear Compton scattering at LUXE
Weizmann Institute of Science（魏茨曼科学研究所）；University College London（伦敦大学学院）；Institute for Particle Physics and Astrophysics, ETH Zurich（苏黎世联邦理工学院粒子物理与天体物理研究所）
Progress towards ultracold Sr for the AION project -- sub-microkelvin atoms and an optical-heterodyne diagnostic tool for injection-locked laser diodes
Laser-driven ion beams have gained considerable attention for their potential use in multidisciplinary research and technology. Pre-clinical studies into their radiobiological effectiveness have established the prospect of using laser-driven ion beams for radiotherapy. In particular, research into the beneficial effects of ultra-high instantaneous dose rates is enabled by the high ion bunch charge and uniquely short bunch lengths present for laser-driven ion beams. Such studies require reliable, online dosimetry methods to monitor the bunch charge for every laser shot to ensure that the prescr…
With electron beam durations down to femtoseconds and sub-femtoseconds achievable in current state-of-the-art accelerators, longitudinal bunch length diagnostics with resolution at the attosecond level are required. In this paper, we present such a novel measurement device which combines a high power laser modulator with an RF deflecting cavity in the orthogonal direction. While the laser applies a strong correlated angular modulation to a beam, the RF deflector ensures the full resolution of this streaking effect across the bunch hence recovering the temporal beam profile with sub-femtosecond…
We report a new scenario of time-of-flight (TOF) technique in which fast neutrons and delayed gamma-ray signals were both recorded in a millisecond time window in harsh environments induced by high-intensity lasers. The delayed gamma signals, arriving far later than the original fast neutron and often being ignored previously, were identified to be the results of radiative captures of thermalized neutrons. The linear correlation between gamma photon number and the fast neutron yield shows that these delayed gamma events can be employed for neutron diagnosis. This method can reduce the detectin…
The high peak current required in free-electron lasers (FELs) is realized by longitudinal compression of the electron bunches to sub-picosecond length. In this paper, a frequency-domain diagnostic method is described that is capable of resolving structures in the femtosecond regime. A novel in-vacuum spectrometer has been developed for spectroscopy of coherent radiation in the THz and infrared range. The spectrometer is equipped with five consecutive dispersion gratings and 120 parallel readout channels; it can be operated either in short wavelength mode (5 - 44 um) or in long wavelength mode …
The National Ignition Facility laser focuses 1.8 Mega-joules of ultraviolet light (wavelength 351 nano-meters) from 192 beams into a 600-micro-meter-diameter volume. Effective use of this output in target experiments requires that the power output from all the beams match within 8% over their entire 20-nanosecond waveform. The scope of NIF beam diagnostics systems necessary to accomplish this task is unprecedented for laser facilities. Each beam line contains 110 major optical components distributed over a 510 meter path, and diagnostic tolerances for beam measurement are demanding. Total lase…
The spectrum of laser-plasma generated X-rays is very important, it characterizes electron dynamics in plasma and is basic for applications. However, the accuracies and efficiencies of existing methods to diagnose the spectrum of laser-plasma based X-ray pulse are not very high, especially in the range of several hundred keV. In this study, a new method based on electron tracks detection to measure the spectrum of laser-plasma produced X-ray pulses is proposed and demonstrated. Laser-plasma generated X-rays are scattered in a multi-pixel silicon tracker. Energies and scattering directions of C…
The versatility of optics enables the design of a wide range of elegant beam instrumentation. Multiple properties of particle beams can be precisely measured by various optical techniques, which include: direct sampling of optical radiation emitted from a charged particle beam; monitoring interactions with an optical probe such as a laserwire; and by electro-optic conversion of the beam signal with high-bandwidth fibre readout. Such methods are typically minimally-invasive and non-destructive, thus permitting diagnostics during accelerator operation without perturbation of the particle beam or…
Laser light scattering systems with volume Bragg grating (VBG) filters, which act as a spectral/angular filter, have often been used as a point measurement technique with spatial resolution as low as a few hundred um defined by the beam waist. In this work, we demonstrate how VBG filters can be leveraged for spatially resolved measurements with several um resolution perpendicular to the laser propagation axis over a few mm along the beam propagation axis. The rejection ring, as determined by the angular acceptance criteria of the filter, is derived analytically, and the use of the ring for 1D …
Gotthard-II is a charge-integrating microstrip detector developed for experiments and diagnostics at free-electron lasers using hard X-rays of 5 keV - 20 keV. Thanks to its excellent single photon sensitivity, large dynamic range as well as high frame rate of 4.5 MHz in burst mode, its potential scientific applications include X-ray absorption/emission spectroscopy, hard X-ray high resolution single-shot spectrometry (HiREX), beam diagnostics, as well as veto signal generation for pixel detectors. The Gotthard-II ASIC has been designed and fabricated using UMC-110 nm technology. The final ASIC…
The Laser-wire will be an essential diagnostic tool at the International Linear Collider. It uses a finely focussed laser beam to measure the transverse profile of electron bunches by detecting the Compton-scattered photons (or degraded electrons) downstream of where the laser beam intersects the electron beam. Such a system has been installed at the PETRA storage ring at DESY, which uses a piezo-driven mirror to scan the laser-light across the electron beam. Lat- est results of experimental data taking are presented and compared to detailed simulations using the Geant4 based program BDSIM.
We present a novel solution to automated beam alignment optimization. This device is based on a Raspberry Pi computer, stepper motors, commercial optomechanics and electronic devices, and the open source machine learning algorithm M-LOOP. We provide schematic drawings for the custom hardware necessary to operate the device and discuss diagnostic techniques to determine the performance. The beam auto-aligning device has been used to improve the alignment of a laser beam into a single-mode optical fiber from manually optimized fiber alignment with an iteration time of typically 20~minutes. We pr…
Expanding laser plasmas, produced by high energy laser radiation, possess both high thermal and magnetic field energy density. Characterization of such plasma is challenging but needed for understanding of its physical behaviour. Among all standard experimental techniques for plasma diagnostics, classical interferometry is one of the most convenient, informative and accurate. Attempts to extract more information from each single laser shot have led to development of complex interferometry, which under certain processing allows to reconstruct both plasma electron density and magnetic field stre…
