arXiv subjects

Jenny List

Publications and source records attributed to Jenny List.

97 records · Page 6Linked to original sources

arXiv2009

Chargino and Neutralino Separation with the ILD Experiment

One of the benchmark processes for the optimisation of the detector concepts proposed for the International Linear Collider is Chargino and Neutralino pair production in an mSugra scenario where Chargino-1 and Neutralino-2 are mass degenerate and decay into W+Neutralino-1 and Z+Neutralino-1, respectively. In this case the separation of both processes in the fully hadronic decay mode is very sensitive to the jet energy resolution and thus to the particle flow performance. The mass resolutions and cross-section uncertainties achievable with the ILD detector concept are studied in full simulation at a center of mass energy of 500 GeV, an integrated luminosity of 500 fb-1 and beam polarisations of P(e+,e-) = (30%, -80%). For the Chargino-1 and Neutralino-2 pair production cross-sections, statistical precisions of 0.84% and 2.75% are achieved, respectively. The masses of Chargino-1, Neutralino-2 and Neutralino-1 can be determined with a statistical precision of 2.9 GeV, 1.7 GeV and 1.0 GeV, respectively.

hep-ex↗

arXiv2009

Resonant laser power build-up in ALPS -- a "light-shining-through-walls" experiment

The ALPS collaboration runs a light-shining-through-walls (LSW) experiment to search for photon oscillations into "weakly interacting sub-eV particles" (WISPs) inside of a superconducting HERA dipole magnet at the site of DESY. In this paper we report on the first successful integration of a large-scale optical cavity to boost the available power for WISP production in this type of experiments. The key elements are a frequency tunable narrow line-width continuous wave laser acting as the primary light source and an electronic feed-back control loop to stabilize the power build-up. We describe and characterize our apparatus and demonstrate the data analysis procedures on the basis of a brief exemplary run.

physics.ins-det↗

arXiv2009

Compton Cherenkov Detector Development for ILC Polarimetry

In order to fully exploit the physics potential of the ILC, it will be necessary to measure (and control) beam parameters to a permille level precision. In case of the beam polarisation, this can only be achieved with dedicated high energy Compton polarimeters and by improving the detector linearity, as well as the calibration of the analyzing power. This note summarises results of an early testbeam period with the Cherenkov detector of the SLD polarimeter, linearity measurements of readout electronics and photodetectors and compares simulation results of the SLD Cherenkov detector with those of a new `U-shaped' prototype.

physics.ins-det↗

arXiv2009

Improvements to the ILC Upstream Polarimeter

The physics programme of the ILC requires polarimetry with yet unprecedented precision. This note focusses on aspects of the upstream polarimeter as described in the ILC Reference Design Report which are not compatible with the extraordinary precision goals. In conclusion, recommendations for improving the design are given.

physics.ins-det↗

arXiv2009

SUSY-P5: Chargino / Neutralino Analysis in the Fully Hadronic Final State

The fully hadronic final states of two signal processes from an mSUGRA inspired scenario (SUSY-P5) are studied within a full simulation of the LDC' detector model. These are chargino pair and neutralino pair production, i.e. e+e- -> C1C1 -> qq'N1 qq'N1 and e+e- -> N2N2 -> qq'N1 qq'N1. Both processes have to be separated sufficiently from all background to measure the respective production cross sections and extract the masses of the involved bosinos, m(C1), m(N2) and m(LSP)=m(N1). This is achieved by fitting the energy spectra of the reconstructed gauge bosons while taking into account the finite width of the boson mass. From simulation data corresponding to 500/fb of luminosity, a mass resolution of about 0.5 GeV seems to be achievable.

hep-ex↗

arXiv2009

Kinematic Fitting in the Presence of ISR at the ILC

Kinematic fitting is a well-established tool to improve jet energy and invariant mass resolutions by fitting the measured values under constraints (e.g. energy conservation). However, in the presence of substantial ISR and Beamstrahlung, naive energy and (longitudinal) momentum constraints fail due to the a priori unknown amount of undetected momentum carried away by collinear photons. It is possible to take care of those two effects and thus obtain significantly higher mass resolutions.

hep-ex↗

arXiv2007

Test Stand Measurements for an ILC Polarimeter

The setup of two different small scale teststands for measurements regarding an electron Cherenkov detector as part of the ILC polarimeters is presented. Component measurements already carried out are analyzed and others, foreseen for the near future, are discussed. The larger one of the two teststands features the old Cherenkov detector of the SLD experiment, which will be used as a reference for a number of crucial measurements. Especially, the requirements for the non-linearity of the read-out chain are studied in greater detail and methods for its precise measurement before and during operation are being developed accordingly.

physics.ins-det↗