Experimental particle physics

  • Article
    | Open Access

    CPT violation could manifest itself in annihilating positronium events, but searching for this effect would require to know the spin of the annihilating system. Here, the authors do this using a positron-emission tomography scanner, finding no violation with a statistical precision of 10−4.

    • P. Moskal
    • , A. Gajos
    •  & W. Wiślicki
  • Article
    | Open Access

    Cherenkov detectors are used to detect high energy particles and their performance capabilities depend heavily on the material used. Here, the authors propose use of a Brewster-optics-based angular filter for a detector with increased sensitivity and particle identification capability.

    • Xiao Lin
    • , Hao Hu
    •  & Yu Luo
  • Article
    | Open Access

    Laser wakefield accelerators are compact sources of ultra-relativistic electrons which are highly sensitive to many control parameters. Here the authors present an automated machine learning based method for the efficient multi-dimensional optimization of these plasma-based particle accelerators.

    • R. J. Shalloo
    • , S. J. D. Dann
    •  & M. J. V. Streeter
  • Article
    | Open Access

    Investigation of exotic electron–nucleon interactions with few-micrometers range requires micrometer-scale, highly-sensitive and well-isolated sensors. Here, the authors use an NV center to set limits on the monopole–dipole interaction between its electron spin and the nucleons of a half-ball lens.

    • Xing Rong
    • , Mengqi Wang
    •  & Jiangfeng Du
  • Article
    | Open Access

    It remains a challenge to find the structure and the distribution of the constituents of nucleons. Here the authors use a scattering method to get information about the gluons and quarks inside a proton and separate the contribution of Bethe-Heitler from the deeply virtual Compton scattering process.

    • M. Defurne
    • , A. Martí Jiménez-Argüello
    •  & P. Zhu
  • Article
    | Open Access

    Antihydrogen studies are important in testing the fundamental principles of physics but producing antihydrogen in large amounts is challenging. Here the authors demonstrate an efficient and high-precision method for trapping and stacking antihydrogen by using controlled plasma.

    • M. Ahmadi
    • , B. X. R. Alves
    •  & J. S. Wurtele
  • Article
    | Open Access

    The detection of Earth’s anti neutrino emission from potassium and the mantle remain elusive. Here the authors propose a method for measuring potassium and mantle geo-neutrinos by detecting their elastic scattering on electrons with direction-sensitive detectors.

    • Michael Leyton
    • , Stephen Dye
    •  & Jocelyn Monroe
  • Article
    | Open Access

    Wakefield accelerators are a cheaper and compact alternative to conventional particle accelerators for high-energy physics and coherent x-ray sources. Here, the authors demonstrate a field gradient in excess of a gigaelectron-volt-per-metre using a terahertz-frequency wakefield supported by a dielectric lined-waveguide.

    • B. D. O’Shea
    • , G. Andonian
    •  & J. B. Rosenzweig
  • Article
    | Open Access

    Rydberg atomic gases have proven a fertile playground for exploring exotic phases of condensed matter systems. Here, Li and Das Sarma study Rydberg-dressed atomic fermions in a 3D optical lattice and find a series of mixed topological density wave phases having no analogue in conventional materials.

    • Xiaopeng Li
    •  & S Das Sarma
  • Article
    | Open Access

    Fundamental theories do not predict a difference between the properties of matter and antimatter, but experimental tests of this are still in their infancy. To this end, this study analyses the effects of electric fields on antihydrogen atoms in the ALPHA trap to place a bound on the charge of antihydrogen.

    • C. Amole
    • , M. D. Ashkezari
    •  & A. E. Charman