330 research outputs found
A Quartz Cherenkov Detector for Compton-Polarimetry at Future e+e- Colliders
Precision polarimetry is essential for future e+ e- colliders and requires
Compton polarimeters designed for negligible statistical uncertainties. In this
paper, we discuss the design and construction of a quartz Cherenkov detector
for such Compton polarimeters. The detector concept has been developed with
regard to the main systematic uncertainties of the polarisation measurements,
namely the linearity of the detector response and detector alignment.
Simulation studies presented here imply that the light yield reachable by using
quartz as Cherenkov medium allows to resolve in the Cherenkov photon spectra
individual peaks corresponding to different numbers of Compton electrons. The
benefits of the application of a detector with such single-peak resolution to
the polarisation measurement are shown for the example of the upstream
polarimeters foreseen at the International Linear Collider. Results of a first
testbeam campaign with a four-channel prototype confirming simulation
predictions for single electrons are presented
A Calibration System for Compton Polarimetry at Linear Colliders
Polarimetry with permille-level precision is essential for future
electron-positron linear colliders. Compton polarimeters can reach negligible
statistical uncertainties within seconds of measurement time. The dominating
systematic uncertainties originate from the response and alignment of the
detector which records the Compton scattered electrons. The robust baseline
technology for the Compton polarimeters foreseen at future linear colliders is
based on an array of gas Cherenkov detectors read out by photomultipliers. In
this paper, we will present a calibration method which promises to monitor
nonlinearities in the response of such a detector at the level of a few
permille. This method has been implemented in an LED-based calibration system
which matches the existing prototype detector. The performance of this
calibration system is sufficient to control the corresponding contribution to
the total uncertainty on the extracted polarisation to better than .Comment: 27 pages, 17 figure
Marshall University Music Department Presents a Faculty Recital, Henning Vauth, Piano
https://mds.marshall.edu/music_perf/1225/thumbnail.jp
Marshall University Music Department Presents the 2014 Birke Fine Arts Festival, Trending Now: Artists and Audiences in the Information Age, Fifth Annual Festival of New Music, Concert Five
https://mds.marshall.edu/music_perf/1293/thumbnail.jp
Spin Transport and Polarimetry in the Beam Delivery System of the International Linear Collider
Polarised electron and positron beams are key ingredients to the physics
programme of future linear colliders. Due to the chiral nature of weak
interactions in the Standard Model - and possibly beyond - the knowledge of the
luminosity-weighted average beam polarisation at the interaction point
is of similar importance as the knowledge of the luminosity and has to be
controlled to permille-level precision in order to fully exploit the physics
potential. The current concept to reach this challenging goal combines
measurements from Laser-Compton polarimeters before and after the interaction
point with measurements at the interaction point. A key element for this
enterprise is the understanding of spin-transport effects between the
polarimeters and the interaction point as well as collision effects. We show
that without collisions, the polarimeters can be cross-calibrated to 0.1 %, and
we discuss in detail the impact of collision effects and beam parameters on the
polarisation value relevant for the interpretation of the collision
data.Comment: 34 pages, 11 figure
Marshall University Music Department Presents a Concert of Soloists Competition, February 5, 2012
https://mds.marshall.edu/music_perf/1192/thumbnail.jp
Marshall University Music Department Presents a MUsic Alive Faculty & Guest Artist Collaboration Series, Freya String Quartet, Henning Vauth, piano, November 15, 2012
https://mds.marshall.edu/music_perf/1199/thumbnail.jp
Marshall University Music Department Presents a Senior Recital, Jared Layman, trombone, assisted by Dr. Henning Vauth, piano and The Hindenburg Experience
https://mds.marshall.edu/music_perf/1263/thumbnail.jp
Marshall University Music Department Presents an American Classics, Michael Stroeher, trombone, and Henning Vauth, piano
https://mds.marshall.edu/music_perf/1234/thumbnail.jp
Marshall University Music Department Presents a Faculty Duo Recital, Şőlen Dikener, cello and Henning Vauth, piano
https://mds.marshall.edu/music_perf/1195/thumbnail.jp
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