93 research outputs found
Searches at HERA
Searches for physics beyond the Standard Model have been performed in
high-energy collisions at HERA. No significant deviation from the
Standard Model has been observed while searching for contact interactions,
extra dimensions, leptoquarks, R-parity violating squarks and excited fermions.
Exclusion limits have been inferred which extend or complement bounds from
other colliders. The H1 collaboration has observed a puzzling excess of events
with an high isolated lepton and missing transverse momentum, and
interpretation as flavour changing neutral currents has been explored.Comment: 7 pages, 6 figures, contribution to the Lake Louise Winter Institut
Study of Phase Reconstruction Techniques applied to Smith-Purcell Radiation Measurements
Measurements of coherent radiation at accelerators typically give the
absolute value of the beam profile Fourier transform but not its phase. Phase
reconstruction techniques such as Hilbert transform or Kramers Kronig
reconstruction are used to recover such phase. We report a study of the
performances of these methods and how to optimize the reconstructed profiles
On the suitability of longitudinal profile measurements using Coherent Smith-Purcell radiation for high current proton beams
The use of Smith-Purcell radiation to measure electrons longitudinal profiles
has been demonstrated at several facilities in the picosecond and
sub-picosecond range. There is a strong interest for the development of non
intercepting longitudinal profile diagnostics for high current proton beams. We
present here results of simulations on the expected yield of longitudinal
profile monitors using Smith-Purcell radiation for such proton beams.Comment: Presented at IPAC 2014 - THPME08
Single Shot Transverse Emittance Measurement of multi-MeV Electron Beams Using a Long Pepper-Pot
We present a pepper-pot design in which we address the problem of penetration
by high energy particle, deriving analytical expressions and performing GEANT4
simulations for the estimation of the error introduced by a long (thick)
pepper-pot. We also show that a careful design allows to measure the emittance
of electron beam of several hundred MeV and beyond
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