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ATLAS

Programme Leaders

Wouter Verkerke & Nicolo de Groot

Main points: scientific

  • Continued exploration of new Higgs channels – this year 4 sigma evidence of ttH production
  • Higgs property measurements – improved measurements of CP and coupling properties, development of unified interpretation framework
  • Direct BSM Searches – First ATLAS general search analysis in 640 final states published
  • Lepton Flavor Violation – Leading the LFV decay analyses of Z and Higgs boson decays.
  • Top physics programme – Starting effort to study top quark couplings in polarized single top production

Main points: technical

  • LHC reaches 100 fb–1 milestone for ATLAS
  • Phase 2 Technical Design Reports approved by ATLAS and CERN (Muon, TDAQ, ITk)
  • Felix Trigger/DAQ system – The final prototype card ready
  • Inner Tracker upgrade – End cap mechanical design finalized, construction studies at Nikhef underway.
  • Leading role in jet favor tagging and muon track reconstruction software

Awards, fellowships etc.

  • Jan Kluyver-prijs 2017: Lydia Brenner
  • DESY Fellowship: Lydia Brenner
  • CERN Fellowship: Pierfrancesco Butti
  • UvA Physics Internal Competition: Ivo Van Vulpen & Hella Snoek (1 PhD)
  • EU ITN INSIGHTS 2017: Wouter Verkerke (2 PhDs)

Key positions in collaborations

  • Data Quality Group: Pamela Convener
  • Coordinator Muon Software: Jochen Meyer
  • Coordinator Muon Drift Tubes: Gerjan Bobbink
  • Coordinators B-physics, Muon trigger: Olya Igonkina, Marcus Morgenstern, resp.
  • Coordinator of the Higgs to WW subgroup: Frank Filthaut
  • FELIX firmware coordinator: Andrea Borga
  • FELIX software coordinator: Mark Dönszelmann
  • ITk global endcap structures activity coordinator: Marcel Vreeswijk

Main paper(s) in 2017

  • Search for Dark Matter Produced in Association with a Higgs Boson Decaying to bb− using 36 fb−1 of pp collisions at √s=13 TeV with the ATLAS Detector – Phys. Rev. Lett. 119 (2017) 181804
  • Search for the Standard Model Higgs boson produced in association with top quarks and decaying into a bb− pair in pp collisions at √s=13 TeV with the ATLAS detector – arXiv:1712.08895 [hep-ex]

LHCb

Programme Leader

Marcel Merk

Main points: scientific

  • CP violation and angle gamma measurement in Bs→ DsK decays.
  • Measurement of matter – antimatter differences in beauty baryon decays,
  • First single experiment observation of of the decay B0s → µ+ µ–,
  • Lepton universality tests in semileptonic b-quark to s-quark decays probes physics beyond the standard model,
  • New lepton universality tests in semileptonic b-quark to c-quark decays using hadronic tau decays.

Main points: technical

  • Construction of the first Velo upgrade encapsulation: de RF-box,
  • Completion of the design of the Velo upgrade detector module,
  • Succesful test of the VeloPix detector chip,
  • Completion of the design of the ColdBox of the Scintillating Fiber detector,
  • Construction of the first SciFi detector module.

Awards, fellowships etc.

  • Marie Curie Fellowship: Sean Benson,
  • LHCb Early career scientist prize: Elena Dall’Occo.

Key positions in collaborations

  • Run coordinator: Niels Tuning,
  • Outer Tracker project leader: Niels Tuning,
  • Working group convenor of charmless b-hadron decays: Sean Benson,
  • Working group convenor of semileptonic B-decays: Greg Ciezarek,
  • Sub-working group convenor of very rare decays: Flavio Archilli,
  • Sub-working group convenor of CP tools and techniques: Sevda Esen.

Main paper(s) in 2017

  • Test of Lepton universality with B0→ K*0ℓ+ℓ– decays, JHEP 1708 (2017) 055.
  • Two extraordinary achievements are the following papers of Nikhef authors in Nature:
    • F. Archilli et al., Flavour-changing neutral currents making and breaking the standard model, doi:10.1038/nature21721.
    • G. Ciezarek et al., A Challenge in Lepton Universality in B Meson Decays, 10.1038/nature22346.

ALICE

Programme Leader

Raimond Snellings

Main points: scientific

  • Measurements of transport properties QGP
  • Observing evidence for collective behaviour in proton-nucleus and proton-proton collisions

Main points: technical

  • First half stave completed of upgrade ITS

Key positions in collaborations

  • Physics coordinator : Marco van Leeuwen
  • Project leader ITS: Paul Kuijer)
  • Physics Working Group Convenors: A. Grelli, R. Snellings, T. Peitzmann

Main paper in 2017

  • Enhanced production of multi-strange hadrons in high-multiplicity proton-proton collisions – ALICE Collaboration (Adam, Jaroslav et al.) Nature Phys. 13 (2017) 535-539 arXiv:1606.07424 [nucl-ex] CERN-EP-2016-153

eEDM

Programme Leader

Steven Hoekstra

Main points: scientific

  • Studied and determined key properties of the BaF electronic structure (energies, lifetimes, branching ratios)
  • Calculated the effective electric field in BaF
  • Obtained a complete set of SrF deceleration data, characterizing the stability in the deceleration process

Main points: technical

  • Prototype transformer for high-voltage upgrade designed and constructed
  • A cryogenic buffer gas source for slow molecular beam is under construction
  • A magnetic field survey of eEDM labs has been performed, which is the first step in constructing the magnetic shielding. Numerical calculations are ongoing.
  • We are optimising the production of supersonic molecular beams

Main paper in 2017

  • Several papers in preparation, but none published yet. We just started in 2017.