Tom Blackburn
A5013728785- Laser-Plasma Interactions and Diagnostics
- Laser-Matter Interactions and Applications
- Laser-induced spectroscopy and plasma
- Atomic and Molecular Physics
- Advanced X-ray Imaging Techniques
- Particle Accelerators and Free-Electron Lasers
- Laser Design and Applications
- Particle physics theoretical and experimental studies
- High-pressure geophysics and materials
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Laser Material Processing Techniques
- Intermetallics and Advanced Alloy Properties
- Botany, Ecology, and Taxonomy Studies
- Gamma-ray bursts and supernovae
- Planetary Science and Exploration
- Particle Detector Development and Performance
- Ocular and Laser Science Research
- Advanced Surface Polishing Techniques
- Advanced Electron Microscopy Techniques and Applications
- Spectroscopy Techniques in Biomedical and Chemical Research
- Advanced Fluorescence Microscopy Techniques
- Crystallography and Radiation Phenomena
University of Gothenburg
2020-2024
University of Birmingham
2023
University of Plymouth
2021
Plasma Technology (United States)
2021
Chalmers University of Technology
2017-2019
University of Sussex
2016-2019
Sussex County Community College
2018
University of Oxford
2013-2015
The dynamics of energetic particles in strong electromagnetic fields can be heavily influenced by the energy loss arising from emission radiation during acceleration, known as reaction. When interacting with a high-energy electron beam, today's lasers are sufficiently intense to explore transition between classical and quantum reaction regimes. We present evidence collision an ultrarelativistic beam generated laser-wakefield acceleration (ϵ>500 MeV) laser pulse (a0>10). measure postcollision...
The NOvA experiment has made a $4.4\sigma$-significant observation of $\bar\nu_{e}$ appearance in 2 GeV $\bar\nu_{\mu}$ beam at distance 810 km. Using $12.33\times10^{20}$ protons on target delivered to the Fermilab NuMI neutrino beamline, recorded 27 $\bar\nu_{\mu} \rightarrow \bar\nu_{e}$ candidates with background 10.3 and 102 \bar\nu_{\mu}$ candidates. This new antineutrino data is combined measure oscillation parameters $|\Delta m^2_{32}| = 2.48^{+0.11}_{-0.06}\times10^{-3}$ eV$^2/c^4$,...
We report results from the first search for νμ→νe transitions by NOvA experiment. In an exposure equivalent to 2.74×1020 protons on target in upgraded NuMI beam at Fermilab, we observe 6 events Far Detector, compared a background expectation of 0.99±0.11(syst) based Near Detector measurement. A secondary analysis observes 11 with 1.07±0.14(syst). The 3.3σ excess observed primary disfavors 0.1π<δCP<0.5π inverted mass hierarchy 90% C.L.Received 19 January...
Ultrastrong electromagnetic fields occur not only in astrophysical settings but also dense lepton bunches, special crystals, and at the focus of high peak power lasers. For sufficient magnitude including quantum electrodynamics effects becomes essential. Electron-positron pair creation interaction these pairs with results fascinating phenomena. In this review particle dynamics are analyzed shown to exhibit complex behavior chaotic motion strange attractors limit cycles, as well cascades...
We present updated results from the NOvA experiment for $\nu_\mu\rightarrow\nu_\mu$ and $\nu_\mu\rightarrow\nu_e$ oscillations an exposure of $8.85\times10^{20}$ protons on target, which represents increase 46% compared to our previous publication. The utilize significant improvements in both simulations analysis data. A joint fit data $\nu_\mu$ disappearance $\nu_e$ appearance gives best point as normal mass hierarchy, $\Delta m^2_{32} = 2.44\times 10^{-3}{{\rm eV}^2}/c^4$,...
Abstract This Conceptual Design Report describes LUXE (Laser Und XFEL Experiment), an experimental campaign that aims to combine the high-quality and high-energy electron beam of European with a powerful laser explore uncharted terrain quantum electrodynamics characterised by both high energy intensity. We will reach this hitherto inaccessible regime physics analysing electron-photon photon-photon interactions in extreme environment provided intense focus. The background its relevance are...
It is possible using current high intensity laser facilities to reach the quantum radiation reaction regime for energetic electrons. An experiment a wakefield accelerator drive GeV electrons into counterpropagating pulse would demonstrate increase in yield of energy photons caused by stochastic nature synchrotron emission: we show that beam $10^9$ 1 colliding with 30 fs $10^{22}~\text{Wcm}^{-2}$ will emit 6300 greater than 700 MeV, $60\times$ number predicted classical theory.
Using a muon neutrino source at Fermilab, the NOvA collaboration has measured disappearance and electron appearance, strengthening constraints on $C\phantom{\rule{0}{0ex}}P$-violating phase in inverted-neutrino-mass-hierarchy case.
This paper reports the first measurement using NOvA detectors of ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ disappearance in a beam. The analysis uses 14 kton-equivalent exposure $2.74\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons-on-target from Fermilab NuMI Assuming normal neutrino mass hierarchy, we measure $\mathrm{\ensuremath{\Delta}}{m}_{32}^{2}=({2.52}_{\ensuremath{-}0.18}^{+0.20})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}\text{ }\text{ }{\mathrm{eV}}^{2}$ and...
Abstract Charged particles accelerated by electromagnetic fields emit radiation, which must, the conservation of momentum, exert a recoil on emitting particle. The force this recoil, known as radiation reaction, strongly affects dynamics ultrarelativistic electrons in intense fields. Such environments are found astrophysically, e.g. neutron star magnetospheres, and will be created laser–matter experiments next generation high-intensity laser facilities. In many these scenarios, energy an...
This Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of $6.05\times10^{20}$ protons-on-target the NuMI beam at Fermi National Accelerator Laboratory. The measurement probes muon-tau symmetry hypothesis that requires maximal mixing ($\theta_{23} = \pi/4$). Assuming normal mass hierarchy, we find $\Delta m^2 (2.67 \pm 0.11)\times 10^{-3}$ eV$^2$ and $\sin^2 \theta_{23}$ two statistically degenerate values...
The DUNE IDR describes the proposed physics program and technical designs of Far Detector modules in preparation for full TDR to be published 2019. It is intended as an intermediate milestone on path a TDR, justifying choices that flow down from high-level goals through requirements at all levels Project. These design will enable experiment make ground-breaking discoveries help answer fundamental questions. Volume 1 contains executive summary general aims this document. remainder first...
Electrons in plasmas produced by next-generation ultraintense lasers ($I>5\ifmmode\times\else\texttimes\fi{}{10}^{22}\phantom{\rule{0.16em}{0ex}}\mathrm{W}/{\mathrm{cm}}^{2}$) can be spin polarized to a high degree (10%--70%) the laser pulses on femtosecond time scale. This is due electrons undergoing spin-flip transitions as they radiate $\ensuremath{\gamma}$-ray photons, preferentially polarizing one direction. Spin polarization modify radiation reaction force electrons, which differs up...
Abstract This Technical Design Report presents a detailed description of all aspects the LUXE (Laser Und XFEL Experiment), an experiment that will combine high-quality and high-energy electron beam European with high-intensity laser, to explore uncharted terrain strong-field quantum electrodynamics characterised by both high energy intensity, reaching Schwinger field beyond. The further implications for search physics beyond Standard Model are also discussed.
ProtoDUNE-SP is the single-phase DUNE Far Detector prototype that under construction and will be operated at CERN Neutrino Platform (NP) starting in 2018. ProtoDUNE-SP, a crucial part of effort towards first 10-kt fiducial mass far detector module (17 kt total LAr mass), significant experiment its own right. With liquid argon (LAr) 0.77 kt, it represents largest monolithic LArTPC to built date. It's technical design given this report.
We report results from the first search for sterile neutrinos mixing with active through a reduction in rate of neutral-current interactions over baseline 810\,km between NOvA detectors. Analyzing 14-kton detector equivalent exposure 6.05$\times$10$^{20}$ protons-on-target NuMI beam at Fermilab, we observe 95 candidates Far Detector compared $83.5 \pm 9.7 \mbox{(stat.)} 9.4 \mbox{(syst.)}$ events predicted assuming only occurs neutrino species. No evidence $\nu_{\mu} \rightarrow \nu_{s}$...
Two signatures of quantum effects on radiation reaction in the collision a ${\sim}$ GeV electron beam with high intensity ( ${>}3\times 10^{20}~\text{W}~\text{cm}^{-2}$ ) laser pulse have been considered. We show that decrease average energy may be used to measure Gaunt factor $g$ for synchrotron emission. derive an equation evolution variance regime, i.e. efficiency parameter $\unicode[STIX]{x1D702}\not \ll 1$ . as direct stochasticity and determine regime where this is observable. For...
Abstract Creation of electrons and positrons from light alone is a basic prediction quantum electrodynamics, but yet to be observed. Our simulations show that the required conditions are achievable using high-intensity two-beam laser facility an advanced target design. Dual irradiation structured produces high-density γ rays then create > 10 8 at intensities 2 × 22 Wcm −2 . The unique feature this setup pair creation primarily driven by linear Breit-Wheeler process ( → e + − ), which...
Accurate modeling is necessary to support precision experiments investigating strong-field QED phenomena. This particularly challenging in the transition between perturbative and nonperturbative regimes, where normalized laser amplitude a0 comparable unity wavelength-scale interference significant. Here, we describe how simulate nonlinear Compton scattering, Breit–Wheeler pair creation, trident creation this regime, using Monte Carlo particle-tracking code Ptarmigan. simulates collisions...
Showers of $\ensuremath{\gamma}$ rays and positrons are produced when a high-energy electron beam collides with superintense laser pulse. We present scaling laws for the electron-beam energy loss, $\ensuremath{\gamma}$-ray spectrum, positron yield that valid in nonlinear, radiation-reaction-dominated regime. As an application we demonstrate by employing collision $>\mathrm{GeV}$ pulse intensity...
State-of-the-art numerical simulations of quantum electrodynamical (QED) processes in strong laser fields rely on a semiclassical combination classical equations motion and QED rates, which are calculated the locally constant field approximation. However, latter approximation is unreliable if amplitude fields, $a_0$, comparable to unity. Furthermore, it cannot, by definition, capture interference effects that give rise harmonic structure. Here we present an alternative approach, resolves...
Abstract When a photon collides with laser pulse, an electron-positron pair can be produced via the nonlinear Breit–Wheeler process. A simulation framework has been developed to calculate this process, which is based on ponderomotive approach that includes strong-field quantum electrodynamical effects locally monochromatic approximation (LMA). Here we compare predictions for variety of observables, in different physical regimes, numerical evaluation exact analytical results from theory. For...
Abstract Observing multiphoton electron–positron pair production (the nonlinear Breit–Wheeler process) requires high-energy γ rays to interact with strong electromagnetic fields. In order for these observations be as precise possible, the would ideally both mono-energetic and highly polarized. Here we perform Monte Carlo simulations of an experimental configuration that accomplishes this in two stages. First, a multi-GeV electron beam interacts moderately intense laser pulse produce bright,...
Ultra-intense laser pulses can create sufficiently strong fields to probe quantum electrodynamics effects in a novel regime. By colliding 60 GeV electron bunch with pulse focussed the maximum achievable intensity of $10^{23}$ Wcm$^{-2}$, we reach much stronger than critical Schwinger field rest frame. When ratio these $\chi_e\gg1$ find that hard ($>25$ \thinspace GeV) radiation from has substantial contribution spin-light. 33% more photons are produced above this energy due spin-light,...