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Coherence and the Successive Contribution in Two-Neutron Transfer reactions

In this short letter we briefly address two important points of two-neutron transfer reactions, namely the successive nature of the process and the role of pairing correlations during this sequential transfer. The discussion is made within the 2-step DWBA formalism. The calculations were carried out making use of software specifically developed for this purpose, which includes successive, simultan

Quantitative study of coherent pairing modes with two-neutron transfer : Sn isotopes

Pairing rotations and pairing vibrations are collective modes associated with a field, the pair field, which changes the number of particles by two. Consequently, they can be studied at profit with the help of two-particle transfer reactions in superfluid and in normal nuclei, respectively. The advent of exotic beams has opened, for the first time, the possibility to carry out such studies in medi

Calculation of the transition from pairing vibrational to pairing rotational regimes between magic nuclei Sn100 and Sn132 via two-nucleon transfer reactions

Absolute values of two-particle transfer cross sections along the Sn-isotopic chain are calculated. They agree with measurements within errors and without free parameters. Within this scenario, the predictions concerning the absolute value of the two-particle transfer cross sections associated with the excitation of the pairing vibrational spectrum expected around the recently discovered closed sh

Dyson treatment of NFT medium polarization processes in superfluid nuclei

We discuss the solution of the Dyson equation (also known as the Nambu-Gor'kov equation) for the case of medium polarization Nuclear Field Theory (NFT) processes in nuclei, and apply it to the nucleus 120Sn. Starting from a mean field obtained with the Sly4 effective nucleon-nucleon force, (mk = 0.7), we renormalize the single-particle states and the pairing interaction through the coupling to col

Nuclear surface dynamics and pairing correlations

We solve the Nambu-Gor'kov equations in 120Sn, demonstrating that the coupling of quasiparticles with collective surface vibrations renormalizes the low-lying part of the nuclear spectrum and influences pairing correlations in a substantial way.

Dynamical processes in the structure of halo nuclei and their experimental evidence

High polarizability and halo phenomena are strongly correlated, as evidenced by the qualitative changes of the nuclear spectrum which arise taking into account the dynamical coupling of the valence neutrons with the collective vibrations of the system. Direct experimental evidence of their role in the induced pairing interaction binding the halo neutrons of 11Li to the core 9Li is provided by the

Contribution of Nuclear Field Theory medium effects to the pairing gap

We calculate the different contributions to the pairing gap for the case of the superfluid nucleus 120Sn, making use of the Dyson equation (also known as the Nambu-Gor'kov equation in the case of superfluid systems) to propagate leading medium polarization Nuclear Field Theory (NFT) processes to all orders. Starting from a mean field obtained with the SLy4 effective force (mk ≈ 0.7), we renormaliz

Dose painting based on tumor uptake of Cu-ATSM and FDG : a comparative study

BACKGROUND: Hypoxia and increased glycolytic activity of tumors are associated with poor prognosis. The purpose of this study was to investigate differences in radiotherapy (RT) dose painting based on the uptake of 2-deoxy-2-[(18) F]-fluorodeoxyglucose (FDG) and the proposed hypoxia tracer, copper(II)diacetyl-bis(N(4))-methylsemithiocarbazone (Cu-ATSM) using spontaneous clinical canine tumor model

A treatment planning and delivery comparison of volumetric modulated arc therapy with or without flattening filter for gliomas, brain metastases, prostate, head/neck and early stage lung cancer

Background. Flattening filter-free (FFF) beams are an emerging technology that has not yet been widely implemented as standard practice in radiotherapy centers. To facilitate the clinical implementation of FFF, we attempted to elucidate the difference in plan quality and treatment delivery time compared to flattening filter beams (i.e. standard, STD) for several patient groups. We hypothesize that

18F-FDG PET/CT for planning external beam radiotherapy alters therapy in 11% of 581 patients

Background: 18F-FDG PET/CT (FDG PET/CT) used in radiotherapy planning for extra-cerebral malignancy may reveal metastases to distant sites that may affect the choice of therapy. Aim: To investigate the role of FDG PET/CT on treatment strategy changes induced by the use of PET/CT as part of the radiotherapy planning. ‘A major change of treatment strategy’ was defined as either including more lesion

Patterns of failure for patients with glioblastoma following O-(2-[18F]fluoroethyl)-L-tyrosine PET- and MRI-guided radiotherapy

Background and purpose To evaluate the patterns of failure following clinical introduction of amino-acid O-(2-[18F]fluoroethyl)-L-tyrosine (FET)-PET-guided target definition for radiotherapy (RT) of glioblastoma patients. Materials and methods The first 66 consecutive patients with confirmed histology, scanned using FET-PET/CT and MRI were selected for evaluation. Chemo-radiotherapy was delivered

Robustness of the Voluntary Breath-Hold Approach for the Treatment of Peripheral Lung Tumors Using Hypofractionated Pencil Beam Scanning Proton Therapy

Purpose The safe clinical implementation of pencil beam scanning (PBS) proton therapy for lung tumors is complicated by the delivery uncertainties caused by breathing motion. The purpose of this feasibility study was to investigate whether a voluntary breath-hold technique could limit the delivery uncertainties resulting from interfractional motion. Methods and Materials Data from 15 patients with

Injectable silver nanosensors:: In vivo dosimetry for external beam radiotherapy using positron emission tomography

Development of safe and efficient radiotherapy routines requires quantification of the delivered absorbed dose to the cancer tissue in individual patients. In vivo dosimetry can provide accurate information about the absorbed dose delivered during treatment. In the current study, a novel silver-nanosensor formulation based on poly(vinylpyrrolidinone)-coated silver nanoparticles formulated in a gel

Validation and Calibration of the EXIT89 Evacuation Model for Road Tunnel Evacuation Applications

The validation of an evacuation model is generally performed through testing its predictive capabilities within a set of standard environments (e.g. buildings) or standard layouts. Unfortunately, non-expert users could consider model results as reliable in unique environments as well, such as road tunnels, and extend their use to applications where no ad hoc validation tests have been performed. T

The association of partial pressures of oxygen and carbon dioxide with neurological outcome after out-of-hospital cardiac arrest : an explorative International Cardiac Arrest Registry 2.0 study

BACKGROUND: Exposure to extreme arterial partial pressures of oxygen (PaO2) and carbon dioxide (PaCO2) following the return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest (OHCA) is common and may affect neurological outcome but results of previous studies are conflicting.METHODS: Exploratory study of the International Cardiac Arrest Registry (INTCAR) 2.0 database, including

Association between pelvic obliquity and scoliosis, hip displacement and asymmetric hip abduction in children with cerebral palsy : a cross-sectional registry study

BACKGROUND: Pelvic obliquity (PO) is common in individuals with cerebral palsy (CP). The prevalence of PO in a population of children with CP and its associations with scoliosis, hip displacement and asymmetric range of hip abduction were analysed. METHODS: Over a 5-year period all pelvic radiographs from the Swedish surveillance programme for CP and the recorded data for scoliosis and hip abducti

Frequency synchronization of a high-order multi-converter system

We investigate the stability properties of a multi-converter power system model, defined on a high-order manifold. For this, we identify its symmetry (i.e., rotational invariance) generated by a static angle shift and rotation of AC signals. We characterize the steady state set, primarily determined by the steady state angles and DC power input. Based on eigenvalue conditions of its Jacobian matri

Health impacts from ambient particle exposure in southern sweden

A health impact assessment (HIA) is an important tool for making informed decisions regarding the design and evaluation of environmental interventions. In this study, we performed a quantitative HIA for the population of Scania (1,247,993), the southernmost county in Sweden, in 2016. The impact of annual mean concentrations of particulate matter with an aerodynamic diameter