# FLC

 2018-08-0710:53 [PUBDB-2018-02765] Preprint/Report et al The DESY II Test Beam Facility [DESY-18-111; arXiv:1807.09328]   DESY Hamburg operates a test beam facility with three independent beam lines at the DESY II synchrotron. It is world-wide one of very few facilities providing test beams in the GeV range. [...] OpenAccess: PDF PDF (PDFA); 2018-07-2619:20 [PUBDB-2018-02704] Book/Report/Master Thesis Moortgat-Pick, G. Vlasov Simulation of Exotic Phase-Space Densities via Tree-Based Domain-Decomposition [DESY-THESIS-2018-022] Hamburg : Verlag Deutsches Elektronen-Synchrotron, DESY-THESIS 77 pp. (2018) [10.3204/PUBDB-2018-02704] = Masterarbeit, Universität Hamburg, 2018   Magnetic bunch compression is used to produce the high-brightness electron bunches needed for the operation of a free-electron laser. A longitudinal energy chirp -- imprinted on the bunch via off-crest acceleration -- results in the compression of the bunch in a subsequent dispersive section of the accelerator in form of a magnetic chicane.Such a setup sets the stage for the self-interaction of charge-density in homogeneities via the space-charge fields they generate within the bunch.This can potentially lead to an enhancement of initially present charge-densitymodulations; an effect known as microbunching amplification.Numerical simulation of this dynamics is encumbered by the fact that phase-space densities of electron bunches encountered at free-electron lasers typically exhibit an exotic'' structure, as they form a thin, hair-like bandmeandering through phase-space.In this thesis, a Vlasov-simulation approach based on tree domain-decomposition is presented, that allows for the efficient simulation of these phase-space densities despite their exoticness.Further, a beam-dynamics model is presented, which most notably enables the time-discrete treatment of collective space-charge effects in drift regions of the accelerator.Based on this model an arbitrary-order perturbation theory for the microbunching gain in a bunch-compressor is conceived and applied to the case of a long bunch with monochromatic density modulation.Finally, the results from theory and simulation are compared as part of thebenchmarking of the simulation code.. OpenAccess: mthesis_amstutz - PDF PDF (PDFA); desy-thesis-18-022-title - PDF PDF (PDFA); 2018-02-0613:52 [PUBDB-2018-01077] Talk (non-conference) Stanitzki, M. The DESY II Test Beam Facility – Status and Future 6th Beam Telescopes and Test Beam Workshop 2018, BTTB6, DESYZürich, DESY, Switzerland, 16 Jan 2018 - 19 Jan 2018   The DESY II Test Beam Facility will resume operations mid February 2018. The current status and possibilities for future improvements and extensions of the facility will be presented.. OpenAccess: PDF PDF (PDFA); External link: Fulltext 2018-01-2411:29 [PUBDB-2018-00782] Book Grefe, M. Particles, Strings and the Early Universe : The Structure of Matter and Space-Time Hamburg : Verlag Deutsches Elektronen-Synchrotron 421 pages (2018) [10.3204/PUBDB-2018-00782]   Within the Collaborative Research Centre SFB 676 “Particles, Strings and the Early Universe: The Structure of Matter and Space-Time” scientists of Universität Hamburg and DESY have conducted research at the interface of mathematical physics, particle physics and cosmology. The SFB 676 was funded by the German Research Foundation (DFG) from 2006 to 2018. [...] OpenAccess: sfb676 - PDF PDF (PDFA); Cover_SFB676_Das Deckblatt_ist von_Herr Grefe-1 - PDF PDF (PDFA); External link: Fulltext HH Handbibliothek ORD 1 arrived HH   ORD 1 arrived 2018-01-1116:31 [PUBDB-2018-00554] Report/Journal Article et al Extracting the top-quark running mass using $t\bar{t} + \hbox {1-jet}$ events produced at the Large Hadron Collider [HU-EP-17-05; LAL-17-034; DESY-17-053; arXiv:1704.00540]   We present the calculation of the next-to-leading order QCD corrections for top-quark pair production in association with an additional jet at hadron colliders, using the modified minimal subtraction scheme to renormalize the top-quark mass. The results are compared to measurements at the Large Hadron Collider run I. [...] Restricted: PDF PDF (PDFA); 2018-01-1011:49 [PUBDB-2018-00325] Preprint/Report et al The role of positron polarization for the inital $250$ GeV stage of the International Linear Collider [DESY-17-237; KEK Preprint 2017-57; SLAC-PUB-17197; arXiv:1801.02840]   The International Linear Collider is now proposed with a staged machine design, with the first stage at $\sqrt{s}=$~250 GeV and an integrated luminosity goal of 2~ab$^{-1}$. One of the questions for the machine design is the importance of positron polarization. [...] OpenAccess: PDF PDF (PDFA); 2018-01-0213:15 [PUBDB-2018-00022] Conference Presentation Behnke, T. The ILD detector concept 2017 International Workshop on Future Linear Colliders, LCWS2017, StrasbourgStrasbourg, France, 23 Oct 2017 - 27 Oct 2017   OpenAccess: PDF PDF (PDFA); 2017-12-2216:09 [PUBDB-2017-14106] Lecture Sefkow, F. Moderne Techniken der Teilchenphysik (Pflichtseminar) Lecture at Heidelberg (), 20 Oct 2017 2017-12-2216:05 [PUBDB-2017-14105] Lecture Sefkow, F. Experimentalphysik IV (Kern- und Teilchenphysik) - Übungen Lecture at Heidelberg (Germany), 21 Apr 2017 - 21 Jul 2017 2017-12-2215:56 [PUBDB-2017-14104] Preprint/Report et al Construction and Response of a Highly Granular Scintillator-based Electromagnetic Calorimeter [arXiv:1707.07126]   A highly granular electromagnetic calorimeter with scintillator strip readout is being developed for future lepton collider experiments. A prototype of 21.5 $X_0$ depth and $180 \times 180$mm$^2$ transverse dimensions was constructed, consisting of 2160 individually read out $10 \times 45 \times 3$ mm$^3$ scintillator strips. [...] OpenAccess: PDF PDF (PDFA);