Ghost Imaging Approach to Photon Energy Resolved Velocity Map Imaging

POSTER

Abstract

Correlating measurements of x-ray observables with properties of the incident beam is a powerful approach to improving measurements with noisy x-ray free electron laser (XFEL) sources. In particular, spectral-domain ghost imaging techniques can facilitate sub-bandwidth resolution in spectroscopic measurements at XFELs, greatly enhancing the scope of time-resolved x-ray absorption and photoelectron studies. Time-resolved experiments using velocity map imaging (VMI) spectrometers also face the limitation of broad bandwidth fundamentally linked to the requisite time-resolution. Here we present a novel approach that combines photon spectrum correlation analysis with the reconstruction of three-dimensional momentum distribution from velocity map images in an efficient, single-step procedure. We demonstrate its efficacy with results on the photoelectron spectra of Argon (Ar 2p) and CS$_{2}$ (S 2p) using the CAMP VMI spectrometer at beamline BL1 of the free-electron laser FLASH. Distinct features are observed despite having splittings that are exceeded by the average bandwidth of the ionizing XFEL pulses. As high-resolution photoelectron spectrum is informative about local chemical environment, our approach can be a powerful tool for studying dynamics in molecular systems.

*This work was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences (BES), Chemical Sciences, Geosciences, and Biosciences Division (CSGB).

Presenters

  • Jun Wang

    • LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
    • Department of Applied Physics, Stanford University; Stanford PULSE Institute, SLAC National Lab

Authors

  • Jun Wang

    • LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
    • Department of Applied Physics, Stanford University; Stanford PULSE Institute, SLAC National Lab

  • Taran Driver

    • SLAC
    • SLAC - Natl Accelerator Lab
    • LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
    • Stanford PULSE Institute, SLAC National Lab; LCLS, SLAC National Lab
    • PULSE Institute, SLAC National Accelerator Laboratory

  • Felix Allum

    • Stanford Univ
    • SLAC National Accelerator Laboratory
    • Stanford University
    • Stanford PULSE Institute, SLAC National Lab; LCLS, SLAC National Lab

  • Christopher Passow

    • Deutsches Elektronen-Synchrotron DESY

  • Christina Papadopoulou

    • Deutsches Elektronen-Synchrotron DESY

  • Günter Brenner

    • Deutsches Elektronen-Synchrotron DESY

  • Siqi Li

    • LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
    • Stanford PULSE Institute, SLAC National Lab; LCLS, SLAC National Lab
    • PULSE Insitute, SLAC National Accelerator Laboratory

  • Stefan Düsterer

    • Deutsches Elektronen-Synchrotron DESY

  • Atia Tul Noor

    • Deutsches Elektronen-Synchrotron DESY

  • Sonu Kumar

    • Deutsches Elektronen-Synchrotron DESY

  • Philip H Bucksbaum

    • Stanford Univ
    • Department of Applied Physics, Stanford University
    • Department of Physics, Stanford University; Department of Applied Physics, Stanford University; Stanford PULSE Institute, SLAC National Lab
    • Stanford University

  • Benjamin Erk

    • DESY
    • Deutsches Elektronen-Synchrotron DESY

  • James P Cryan

    • SLAC National Lab
    • LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
    • Stanford PULSE Institute, SLAC National Lab; LCLS, SLAC National Lab
    • SLAC National Accelerator Laboratory

  • Ruaridh Forbes

    • SLAC - Natl Accelerator Lab
    • Stanford PULSE Institute, SLAC National Accelerator Laboratory
    • Stanford PULSE Institute, SLAC National Lab; LCLS, SLAC National Lab; Department of Physics, Stanford University
    • SLAC National Accelerator Laboratory