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Ursula Keller wins “Swiss Nobel” Marcel Benoist Prize- for pioneering work in ultrafast lasers

Farewell: the NCCR MUST ended - on June 30, 2022

MUST2022 Conference- a great success!

New scientific highlights- by MUST PIs Wörner, Chergui, and Richardson

FELs of Europe prize for Jeremy Rouxel- “Development or innovative use of advanced instrumentation in the field of FELs”

Ruth Signorell wins Doron prizefor pioneering contributions to the field of fundamental aerosol science

New FAST-Fellow Uwe Thumm at ETH- lectures on Topics in Femto- and Attosecond Science

International Day of Women and Girls in Science- SSPh asked female scientists about their experiences

New scientific highlight- by MUST PIs Milne, Standfuss and Schertler

EU XFEL Young Scientist Award for Camila Bacellar,beamline scientist and group leader of the Alvra endstation at SwissFEL

Prizes for Giulia Mancini and Rebeca Gomez CastilloICO/IUPAP Young Scientist Prize in Optics & Ernst Haber 2021

Nobel Prize in Chemistry awarded to RESOLV Member Benjamin List- for the development of asymmetric organocatalysis

Hans Jakob Wörner invited to give the „New Horizons Solvay Lectures” - online, October 5, 12 and 19

Unusual keynote talk at an international scientific conference- Do photons show gender bias?

NCCR MUST at Scientifica 2021- Lightning, organic solar cells, and virtual molecules

Velocity map imaging spectrometer (VMIS)

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Location		Contact
ETH Zurich, IQE Ultrafast Laser Physics Wolfgang-Pauli-Strasse 16 8093 Zurich		Dr. Jochen Maurer Tel. +41 44 633 7024 9jok+cmb3aus1rea6@py3hys9s.s'etx+hzs3.cv1hy

Configuration / Setup		Literature
This Velocity Map Imaging Spectrometer can be used to measure 2D momentum distributions of electrons or ions after ionization and is capable of the reconstruction of full 3D momentum distributions by tomographic reconstruction. Targets: Atoms and molecules in gas phase Available ionization light sources: MIR to XUV Energy range: up to 100 eV Momentum resolution: Δp/p = 1/200		A. T. J. B. Eppink and D. H. Parker, Rev. Sci. Instrum. 68, 3477 (1997) T. Remetter, P. Johnsson, J. Mauritsson, K. Varjú, Y. Ni, F. Lépine, E. Gustafsson, et al., Nature Physics 2(5), 323–326 (2006) M. Wollenhaupt, M. Krug, J. Köhler, T. Bayer, C. Sarpe-Tudoran, T. Baumert, Appl Phys B 95, 647-651 (2009)

. The left/top image shows a sketch of the setup consisting of an UHV chamber with a leak valve gas target and adjustable focusing geometries. In the vertical direction, three circular electrodes with adjustable voltages in the kV range enable imaging of charged particle momentum distributions by projecting them onto the MCP (top). The imaging system with three electrodes (called repeller, extractor and ground) is shown in detail in the right/bottom image together with example trajectories from the focus to the MCP. In this VMIS, the gas valve is directly integrated in the repeller electrode to achieve higher gas densities.		Ultrashort light pulses of suitable energy ionize gases in the focal volume right above the repeller electrode. The resulting charged particle cloud is accelerated towards and mapped onto the detector plane. The resulting image, recorded with an MCP followed by a phosphor screen and a CCD camera, is a projection of the particle momentum distribution. The setup is suitable for a wide range of gaseous targets from noble gases to molecules. For ionization of these gases, sources at different wavelengths are available in our laboratory: 800 nm (up to 200 μJ, 10 kHz, <6 fs), 1.5 μm (1.5 mJ, 1 kHz, 20 fs), 3.5 μm (14 µJ, 100 kHz, <100 fs) and single attosecond pulses in the XUV range (15-45 eV).