Search results for "Masses"
showing 10 items of 98 documents
Lattice quark masses: a non-perturbative measurement
1998
We discuss the renormalization of different definitions of quark masses in the Wilson and the tree-level improved SW-Clover fermionic action. For the improved case we give the correct relationship between the quark mass and the hopping parameter. Using perturbative and non-perturbative renormalization constants, we extract quark masses in the $\MSbar$ scheme from Lattice QCD in the quenched approximation at $\beta=6.0$, $\beta=6.2$ and $\beta=6.4$ for both actions. We find: $\bar{m}^{\MSbar}(2 GeV)=5.7 \pm 0.1 \pm 0.8$ MeV, $m_s^{\MSbar}(2GeV)= 130 \pm 2 \pm 18 $ MeV and $m_c^{\MSbar}(2 GeV) = 1662\pm 30\pm 230$ MeV.
Up, down, strange and charm quark masses with N-f=2+1+1 twisted mass lattice QCD
2014
We present a lattice QCD calculation of the up, down, strange and charm quark masses performed using the gauge configurations produced by the European Twisted Mass Collaboration with N-f = 2 + 1 + 1 dynamical quarks, which include in the sea, besides two light mass degenerate quarks, also the strange and charm quarks with masses close to their physical values. The simulations are based on a unitary setup for the two light quarks and on a mixed action approach for the strange and charm quarks. The analysis uses data at three values of the lattice spacing and pion masses in the range 210-450 MeV, allowing for accurate continuum limit and controlled chiral extrapolation. The quark mass renorma…
High-precision mass measurements and production of neutron-deficient isotopes using heavy-ion beams at IGISOL
2019
An upgraded ion-guide system for the production of neutron-deficient isotopes with heavy-ion beams has been commissioned at the IGISOL facility with an $^{36}\mathrm{Ar}$ beam on a $^{\mathrm{nat}}\mathrm{Ni}$ target. It was used together with the JYFLTRAP double Penning trap to measure the masses of $^{82}\mathrm{Zr}, ^{84}\mathrm{Nb}, ^{86}\mathrm{Mo}, ^{88}\mathrm{Tc}$, and $^{89}\mathrm{Ru}$ ground states and the isomeric state $^{88}\mathrm{Tc}^{m}$. Of these, $^{89}\mathrm{Ru}$ and $^{88}\mathrm{Tc}^{m}$ were measured for the first time. The precision of measurements of $^{82}\mathrm{Zr}, ^{84}\mathrm{Nb}$, and $^{88}\mathrm{Tc}$ was significantly improved. The literature value for $^…
Influence of mobile ions on the electroluminescence characteristics of methylammonium lead iodide perovskite diodes
2016
In this work, we study the effect of voltage bias on the optoelectronic behavior of methylammonium lead iodide planar diodes. Upon biasing the diodes with a positive voltage, the turn-on voltage of the electroluminescence diminishes and its intensity substantially increases. This behavior is reminiscent of that observed in light-emitting electrochemical cells (LECs), single-layer electroluminescent devices in which the charge injection is assisted by the accumulation of ions at the electrode interface. Because of this mechanism, performances are largely independent from the work function of the electrodes. The similarities observed between planar perovskite diodes and LECs suggest that mobi…
Somatic embryogenesis of Vitis vinifera L. (cv Sugraone) from stigma and style culture
2015
Somatic embryo and plant regeneration were induced from stigma and style culture of grapevine (Vitis vinifera L. cv. Sugraone). To obtain somatic embryogenesis, explants were cultured on Nitsch and Nitsch basal medium (NN) supplemented with 88 mM sucrose and various combinations of the auxin β-naphthoxyacetic acid (NOA, 0-10 μM) and the cytokinin 6-benzylaminopurine (BA, 0-9 μM). Growth regulators (BA and NOA) in the culture medium were essential for induction of somatic embryogenesis since explants incubated on hormone-free medium never regenerated somatic embryos. Usually, the regenerated somatic embryos become visible as small white globular structures on the surface of the callus 3-4 mo…
LAPAROSCOPIC ADRENALECTOMY: SINGLE CENTRE EXPERIENCE.
2013
Objective: Laparoscopic adrenalectomy is today considered the gold standard treatment for all benign adrenal tumors. The aim of this study is to evaluate the results of laparoscopic adrenalectomy in a single centre. Methods: We reviewed clinical data on 32 adrenalectomies performed at our istitution from 2009 to 2012. The average age of patients was 47 years (range 38-68); 18 were men and 14 women. For the clinical analysis, patients were divided into the nonfunctioning tumor group (n = 20) and the functioning tumor group (n = 12). All operations were performed via transperitoneal lateral access. Results: All laparoscopic adrenalectomy were finished successfully and no open surgery was nece…
UN ERRORE DIAGNOSTICO IN CHIRURGIA PEDIATRICA: La pielonefrite grantogranulomatosa ed il Tumore di Wilms
1993
The Authors report a case of Xanthogranulomatous Pyelonephritis characterized by a torpid course and clinical presentation of renal mass.
A CASE OF A PRESACRAL MYELOLIPOMA: IMAGING FINDINGS AND DIFFERENTIAL DIAGNOSIS CHECKLIST OF OTHER PRESACRAL MASSES
2013
PURPOSE: There have been many reports describing adrenal myelolipoma but there have been only few reports of extraadrenal myelolipoma. We describe a case of an elderly woman with lower back pain due to age-related spondyloarthrosis and mild discopathy with a presacral myelolipoma as incidental finding. We also discuss about common and uncommon imaging findings of other presacral masses. METHODS: A 74 years-old woman came to our observation to perform an MRI of the lumbar spine for typical lumbar back pain. MR imaging revealed, in addition to the signs of mild scoliosis and spondylo-disc-arthrosis, a presacral mass showing heterogeneously high signal in all sequences and almost completely su…
Presacral Myelolipoma
2014
Many reports have described adrenal myelolipomas but there have been only a few reports of extra-adrenal myelolipomas. We describe a 74-year-old woman who came to our observa- tion for MRI of the lumbar spine for typical lumbar back pain. In addition to signs of mild scoliosis and spondylo disc arthrosis, MR imaging revealed a presacral mass showing a heterogeneously high signal in all pulse sequences and almost completely suppressed on inversion recovery sequences for fat tissue. CT imaging confirmed the fatty nature of the lesion and no signs of bone involvement. These findings were most consistent with a diagnosis of a rare presacral myelolipoma as confirmed at histopathologic analysis. …
Cosmic microwave background constraints on secret interactions among sterile neutrinos
2017
Secret contact interactions among eV sterile neutrinos, mediated by a massive gauge boson $X$ (with $M_X \ll M_W$), and characterized by a gauge coupling $g_X$, have been proposed as a mean to reconcile cosmological observations and short-baseline laboratory anomalies. We constrain this scenario using the latest Planck data on Cosmic Microwave Background anisotropies, and measurements of baryon acoustic oscillations (BAO). We consistently include the effect of secret interactions on cosmological perturbations, namely the increased density and pressure fluctuations in the neutrino fluid, and still find a severe tension between the secret interaction framework and cosmology. In fact, taking i…