87 research outputs found
Four Decades of Computing in Subnuclear Physics - from Bubble Chamber to LHC
This manuscript addresses selected aspects of computing for the
reconstruction and simulation of particle interactions in subnuclear physics.
Based on personal experience with experiments at DESY and at CERN, I cover the
evolution of computing hardware and software from the era of track chambers
where interactions were recorded on photographic film up to the LHC experiments
with their multi-million electronic channels
Can the neutrino speed anomaly be defended?
The OPERA collaboration reported [1] a measurement of the neutrino velocity
exceeding the speed of light by 0.025%. For the 730 km distance from CERN in
Geneva to the OPERA experiment an early arrival of the neutrinos of 60.7 ns is
measured with an accuracy of \pm6.9 ns (stat.) and \pm7.4 ns (sys.). A basic
assumption in the analysis is that the proton time structure represents exactly
the time structure of the neutrino flux. In this manuscript, we challenge this
assumption. We identify two main origins of systematic effects: a group delay
due to low pass filters acting on the particular shape of the proton time
distribution and a movement of the proton beam at the target during the leading
and trailing slopes of the spill
Web-Mining mit Methoden des Information Retrievals - Personalisierung von Web-Sites auf Basis von Webtracking Daten
Saddle-nodes and period-doublings of smale horseshoes: a case study near resonant homoclinic bellows
Abstract In unfoldings of resonant homoclinic bellows interesting bifurcation phenomena occur: two suspensed Smale horseshoes can collide and disappear in saddle-node bifurcations (all periodic orbits disappear through saddle-node bifurcations, there are no other bifurcations of periodic orbits), or a suspended horseshoe can go through saddle-node and period-doubling bifurcations of the periodic orbits in it to create an additional "doubled horseshoe"
Saddle-nodes and period-doublings of smale horseshoes: a case study near resonant homoclinic bellows
Lin's method for heteroclinic chains involving periodic orbits
We present an extension of the theory known as Lin's method to heteroclinic
chains that connect hyperbolic equilibria and hyperbolic periodic orbits. Based
on the construction of a so-called Lin orbit, that is, a sequence of continuous
partial orbits that only have jumps in a certain prescribed linear subspace,
estimates for these jumps are derived. We use the jump estimates to discuss
bifurcation equations for homoclinic orbits near heteroclinic cycles between an
equilibrium and a periodic orbit (EtoP cycles)
Endothelin Receptor Antagonists Attenuate the Inflammatory Response of Human Pulmonary Vascular Smooth Muscle Cells to Bacterial Endotoxin
- …