Mon·Nov 25, 2019Monday·November 25, 2019

1. 01*

   "Thermal Spike" model applied to thin targets irradiated with swift heavy ion beams at few MeV/u

   Christelle Stodel (GANIL) · Marcel Toulemonde (CIMAP - UMR 6252) · Christoph Fransen · Bertrand Jacquot (GANIL) · Emmanuel Clément (GANIL) · Christian Dufour (CIMAP - UMR 6252)

   High electronic excitations in radiation of metallic targets with swift heavy ion beams at the coulomb barrier play a dominant role in the damaging processes of some metals. The inelastic thermal spike model was developed to describe tracks in materials and is applied in this paper to some systems beams/targets employed recently in some nuclear physics experiments. Taking into account the experimental conditions and the approved electron-phonon coupling factors, the results of the calculation enable to interpret the observation of the fast deformation of some targets.

   ↳ physics.ins-detnucl-exphysics.acc-phEPJ Web Conf.(2020)·1 citation
2. 02*

   Radiation Damage Studies on Titanium Alloys as High Intensity Proton Accelerator Beam Window Materials

   Taku Ishida🇯🇵 · Eiichi Wakai🇯🇵 · Shunsuke Makimura🇯🇵 · Patrick G. Hurh🇺🇸 · Kavin Ammigan🇺🇸 · Andrew M. Casella🇺🇸 · Danny J. Edwards🇺🇸 · David J. Senor🇺🇸 · Christopher J. Densham🇬🇧 · Michael Fitton🇬🇧 · Joe Bennett🇬🇧 · Dohyun Kim🇺🇸 and 3 other authors

   A high-strength dual alpha+beta phase titanium alloy Ti-6Al-4V is utilized as a material for beam windows in several accelerator target facilities. However, relatively little is known about how material properties of this alloy are affected by high-intensity proton beam irradiation. With plans to upgrade neutrino facilities at J-PARC and Fermilab to over 1 MW beam power, the radiation damage in the window material will reach a few displacements per atom (dpa) per year, significantly above the ~0.3 dpa level of existing data. The RaDIATE collaboration has conducted a high intensity proton beam irradiation of various target and window material specimens at BLIP facility, including a variety of titanium alloys. Post-Irradiation Examination of the specimens in the 1st capsule, irradiated at up to 0.25 dpa, is in progress. Tensile tests in a hot cell at PNNL exhibited a clear signature of radiation hardening and loss of ductility for Ti-6Al-4V, while Ti-3Al-2.5V, with less beta phase, exhibited less severe hardening. Microstructural investigations will follow to study the cause of the difference in tensile behavior between these alloys. High-cycle fatigue (HCF) performance is critical to the lifetime estimation of beam windows exposed to a periodic thermal stress from a pulsed proton beam. The 1st HCF data on irradiated titanium alloys are to be obtained by a conventional bend fatigue test at Fermilab and by an ultrasonic mesoscale fatigue test at Culham Laboratory. Specimens in the 2nd capsule, irradiated at up to ~1 dpa, cover typical titanium alloy grades, including possible radiation-resistant candidates. These systematic studies on the effects of radiation damage of titanium alloys are intended to enable us to predict realistic lifetimes of current beam windows made of Ti-6Al-4V and to extend the lifetime by choosing a more radiation and thermal shock tolerant alloy.

   ↳ physics.ins-dethep-exnucl-exphysics.acc-phJPS Conf.Proc.(2020)·8 citations
3. 03*

   A Fast Universal Kinematic Fitting code for low-energy nuclear physics: FUNKI_FIT

   R. Smith🇬🇧 · J. Bishop🇺🇸

   We present an open source kinematic fitting routine designed for low-energy nuclear physics applications. Although kinematic fitting is commonly used in high-energy particle physics, it is rarely used in low-energy nuclear physics, despite its effectiveness. A FORTRAN and ROOT C++ version of the FUNKI_FIT kinematic fitting code have been developed and published open access. The FUNKI_FIT code is universal in the sense that the constraint equations can be easily modified to suit different experimental set-ups and reactions. Two case studies for the use of this code, utilising experimental and Monte-Carlo data, are presented: (1) charged-particle spectroscopy using silicon-strip detectors; (2) charged-particle spectroscopy using active target detectors. The kinematic fitting routine provides an improvement in resolution in both cases, demonstrating, for the first time, the applicability of kinematic fitting across a range of nuclear physics applications. The ROOT macro has been developed in order to easily apply this technique in standard data analysis routines used by the nuclear physics community.

   ↳ physics.ins-detnucl-exMDPI Physics(2019)·6 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.