Search results for "Accelerator"
showing 10 items of 1507 documents
Top quark mass measurement in radiative events at electron-positron colliders
2020
In this letter, we evaluate potential of linear $e^+e^-$ colliders to measure the top quark mass in radiative events and in a suitable short-distance scheme. We present a calculation of the differential cross section for production of a top quark pair in association with an energetic photon from initial state radiation, as a function of the invariant mass of the $t\bar{t}$ system. This {\it matched} calculation includes the QCD enhancement of the cross section around the $t\bar{t}$ production threshold and remains valid in the continuum well above the threshold. The uncertainty in the top mass determination is evaluated in realistic operating scenarios for the Compact Linear Collider (CLIC)…
The International Linear Collider Project—Its Physics and Status
2021
The discovery of Higgs particle has ushered in a new era of particle physics. Even though the list of members of the standard theory of particle physics is now complete, the shortcomings of the theory became ever more acute. It is generally considered that the best solution to the problems is an electron–positron collider that can study Higgs particle with high precision and high sensitivity; namely, a Higgs factory. Among a few candidates for Higgs factory, the International Linear Collider (ILC) is currently the most advanced in its program. In this article, we review the physics and the project status of the ILC including its energy expandability.
Measurement of the parity violating asymmetry in the quasielastic electron-deuteron scattering and improved determination of the magnetic strange for…
2016
A new measurement of the parity-violating asymmetry in the electron-deuteron quasielastic scattering for backward angles at $⟨{Q}^{2}⟩=0.224\text{ }\text{ }{(\mathrm{GeV}/c)}^{2}$, obtained in the A4 experiment at the Mainz Microtron accelerator (MAMI) facility, is presented. The measured asymmetry is ${A}_{PV}^{d}=(\ensuremath{-}20.11\ifmmode\pm\else\textpm\fi{}0.8{7}_{\mathrm{stat}}\ifmmode\pm\else\textpm\fi{}\phantom{\rule{0ex}{0ex}}1.0{3}_{\mathrm{sys}})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$. A combination of these data with the proton measurements of the parity-violating asymmetry in the A4 experiment yields a value for the effective isovector axial-vector form facto…
International Scoping Study (ISS) for a future neutrino factory and Super-Beam facility. Detectors and flux instrumentation for future neutrino facil…
2009
Technical report by The ISS Detector Working Group; This report summarises the conclusions from the detector group of the International Scoping Study of a future Neutrino Factory and Super-Beam neutrino facility. The baseline detector options for each possible neutrino beam are defined as follows: 1. A very massive (Megaton) water Cherenkov detector is the baseline option for a sub-GeV Beta Beam and Super Beam facility. 2. There are a number of possibilities for either a Beta Beam or Super Beam (SB) medium energy facility between 1-5 GeV. These include a totally active scintillating detector (TASD), a liquid argon TPC or a water Cherenkov detector. 3. A 100 kton magnetized iron neutrino det…
Search for large extra spatial dimensions in dimuon production with the D0 detector
2005
We present the results of a search for the effects of large extra spatial dimensions in $p{\bar p}$ collisions at $\sqrt{s} =$ 1.96 TeV in events containing a pair of energetic muons. The data correspond to 246 \ipb of integrated luminosity collected by the \D0 experiment at the Fermilab Tevatron Collider. Good agreement with the expected background was found, yielding no evidence for large extra dimensions. We set 95% C.L. lower limits on the fundamental Planck scale between 0.85 TeV and 1.27 TeV within several formalisms. These are the most stringent limits achieved in the dimuon channel to date.
Feasibility of photodetachment isobar suppression of WF with respect to HfF
2014
Abstract The feasibility of using laser photodetachment as a means for isobar suppression in accelerator mass spectrometry has been investigated for the special case of HfF 5 − /WF 5 − . A method for absolute photodetachment cross section measurements was applied and the cross sections of tungsten pentafluoride and hafnium pentafluoride negative ions were measured. The measurements indicate that the photodetachment cross section for WF 5 − is at least 100 times larger than for HfF 5 − at the wavelength of the fourth harmonic of the Nd:YAG laser at 266 nm. The absolute cross section for WF 5 − at this photon energy was found to be (2.8 ± 0.3) × 10 −18 cm 2 , while an upper limit of 2 × 10 −…
Indicator system and suspension of the old egyptian scales
1989
Abstract Detailed analysis of drawings of both the death balance and scales of daily life together uith technical considerations suggest a triangular pointer perpendicular to the balance beam and a plummet suspended in front of the beam. The suspension was made using a rope or metal rings, the axis most probably piercing the beam horizontally.
Pressure dependence of photoluminescence of InAs/InP self-assembled quantum wires
2007
6 páginas, 4 figuras, 1 tabla.-- PACS 62.50.+ p, 73.21.Hb, 78.55.Cr, 78.67.Lt, 81.15.Hi, 81.16.Dn
Sensitivity of alanine dosimeters with gadolinium exposed to 6 MV photons at clinical doses.
2011
In this study we analyzed the ESR signal of alanine dosimeters with gadolinium exposed to 6 MV linear accelerator photons. We observed that the addition of gadolinium brings about an improvement in the sensitivity to photons because of its high atomic number. The experimental data indicated that the addition of gadolinium increases the sensitivity of the alanine to 6 MV photons. This enhancement was better observed at high gadolinium concentrations for which the tissue equivalence is heavily reduced. However, information about the irradiation setup and of the radiation beam features allows one to correct for this difference. Monte Carlo simulations were carried out to obtain information on …
Investigation of correction factors for non-reference conditions in ion chamber photon dosimetry with Monte-Carlo simulations.
2009
Current dosimetry protocols require geometrical reference conditions for the determination of absorbed dose in external radiotherapy. Whenever these geometrical conditions cannot be maintained the application of additional corrections becomes necessary, in principle. The current DIN6800-2 protocol includes a corresponding factor k(NR), but numerical values are lacking and no definite information about the magnitude of this correction is available yet. This study presents Monte-Carlo based calculations within the 6 MV-X photon field of a linear accelerator for a common used ion chamber (PTW31010) employing the EGSnrc code system. The linear accelerator model was matched to measurements, show…