arXiv subjects

Victor Steiner

Publications and source records attributed to Victor Steiner.

5 recordsLinked to original sources

arXiv2024

Concrete and Lead Shielding Requirements for PET Facilities

We investigate shielding thickness requirements in concrete and lead walls for positron emission tomography (PET) facilities. F\textsuperscript{18}, the most commonly used PET radiotracer, emits two back-to-back 511 keV photons, necessitating effective shielding to protect hospital staff while patients are in treatment rooms and during their hospital stay. Photon transmission measurements were conducted through a standard Israeli B30 concrete wall (3 m high, 20 cm thick) using photons from an F\textsuperscript{18} source. A narrow-beam transmission coefficient of $ T = (3.0 \pm 1.0)\% $ was recorded with the source positioned 0.05 m from the wall, and the detector at distances of 0.05--3.0 m on the opposite side. When the source is 3 meters from the wall, photons within a 0.64 m radius circular disk (wide-beam) strike the wall. This produces a dose ``buildup'' effect, whereby photons striking within the disk reach the dosimeter after Compton scattering within the wall. The wide-beam transmission coefficient was measured as $ T = (8.8 \pm 1.8)\% $, corresponding to a buildup factor $ B = 4.0 \pm 0.8 $, consistent with Monte Carlo (MC) simulations $ B = 3.9 \pm 0.6 $, validating the simulation reliability for this specific setup. Note however that reliance solely on thick concrete walls presents construction challenges due to weight, space, and cost inefficiency. Since ordinary concrete effectively interacts only through Compton scattering, while lead walls interact via the photoelectric effect, lead is preferable for shielding. A 3.3 cm lead wall results in $ < 0.5\% $ transmission, and lead sheets can be supported by a 5 cm gypsum wall, optimizing shielding design. However, considering the environmental toxicity of lead, note that recent studies advocate the use of tungsten carbide.

physics.med-ph↗

arXiv1999

Inelastic electron-pion scattering at FNAL (SELEX)

In this report we describe the analysis status of electron-pion inelastic scattering $πe \to π' e' γ$ and $πe \to π' e' π^0$ reaction data, measured in inverse pion-electron scattering at 590 GeV/c at FNAL. The data give information on reactions that were never previously measured: (1) $πe \to ρe'$ scattering for a determination of the $ρ\to πγ$ radiative width from a measurement of the transition form factor near zero momentum transfer, (2) $ πe \to e' π' π^0$ scattering near threshold for a determination of the chiral anomaly transition form factor and the $γ\to 3 π$ F$_{3π}$ chiral anomaly amplitude, and (3) $πe \to π' e' γ$ scattering, in which a virtual photon from the electron's Coulomb field is Compton scattered on the pion, for a determination of the never previously measured generalized pion polarizabilities.

hep-ex↗

arXiv1999

Hadron-Photon Interactions in COMPASS

The COMPASS experiment at CERN SPS will use hadron beams (pion, kaon and proton) and muons at 50-280 GeV/c and virtual photon targets to investigate, via Primakoff effect, important hadron properties: polarizability, chiral anomaly, radiative transitions and hybrid meson production. We present simulation studies to optimize the beam, detector setup and trigger for measuring with high statistics above topics.

hep-ex↗

arXiv1998

Primakoff Physics for CERN COMPASS Hadron Beam: Hadron Polarizabilities, Hybrid Mesons, Chiral Anomaly, Meson Radiative Transitions

We describe a hadron physics program attainable with a partially instrumented CERN COMPASS spectrometer, involving tracking detectors and moderate-size ECAL2/HCAL2 calorimeters. COMPASS can realize a state-of-the-art hadron beam physics program based on hadron polarizability, hybrid mesons, chiral anomaly, and meson radiative transition studies. We review here the physics motivation for this hadron beam program. We describe the beam, detector, trigger requirements, and hardware/software requirements for this program. The triggers for all this physics can be implemented for simultaneous data taking. The program is based on using a hadron beam (positive/negative pion, kaon, proton) in COMPASS.

hep-ex↗

arXiv1998

Pion and Kaon Polarizabilities and Radiative Transitions

CERN COMPASS plans measurements of gamma-pi and gamma-K interactions using 50-280 GeV pion (kaon) beams and a virtual photon target. Pion (kaon) polarizabilities and radiative transitions will be measured via Primakoff effect reactions such as pi+gamma->pi'+gamma and pi+gamma->meson. The former can test a precise prediction of chiral symmetry; the latter for pi+gamma->a1(1260) is important for understanding the polarizability. The radiative transition of a pion to a low mass two-pion system, pi+gamma->pi+pi0, can also be studied to measure the chiral anomaly amplitude F(3pi) (characterizing gamma->3pi), arising from the effective Chiral Lagrangian. We review here the motivation for the above physics program. We describe the beam, target, detector, and trigger requirements for these experiments. We also describe FNAL SELEX attempts to study related physics via the interaction of 600 GeV pions with target electrons. Data analysis in progress aims to identify the reactions pi+e->pi'+e'+pi0 related to the chiral anomaly, and pi+e->pi'+e'+gamma related to pion polarizabilities.

hep-ex↗