Search results for "Nuclei"
showing 10 items of 1273 documents
Interweaving of elementary modes of excitation in superfluid nuclei through particle-vibration coupling: Quantitative account of the variety of nucle…
2015
A complete characterization of the structure of nuclei can be obtained by combining information arising from inelastic scattering, Coulomb excitation, and γ -decay, together with one- and two-particle transfer reactions. In this way it is possible to probe both the single-particle and collective components of the nuclear many-body wave function resulting from the coupling of these modes and, as a result, diagonalizing the low-energy Hamiltonian. We address the question of how accurately such a description can account for experimental observations in the case of superfluid nuclei. Our treatment goes beyond the traditional approach, in which these properties are calculated separately, and mos…
b-decay of 116Agm and the vibrational structure of 116Cd
2001
The structure of near neutron midshell 116 Cd has been investigated via β decay of 116 Ag m by β-γ and γ-γ coincidence spectroscopy. The 116 Ag m activity was produced by symmetric fission of natural uranium induced by 25 MeV protons. The ion guide technique has been employed to produce online mass separated sources. The decay scheme of 116 Ag m has been considerably extended by adding 19 new excited states of 116 Cd . The newly identified 116 Cd state at 1869.7 keV, along with other four levels near 2 MeV, are interpreted as forming the complete three-phonon quintuplet. The vibrational structure of 116 Cd is discussed in the context of an anharmonic vibrator. peerReviewed
Development of functionalized SYBR green II related cyanine dyes for viral RNA detection
2020
Fluorescent probes for sensing nucleic acids have found widespread use in the field of cell and molecular biology. However, probes combined with potential for post-synthetic conjugation, e.g. for intra-endosomal measurements of RNA, are unavailable. Herein we developed cyanine dyes that can be conjugated to viral capsid or other targets. First, we solved the crystal structure of SYBR Green II. The structural elucidation of this commonly used RNA probe provided the basis for synthesizing similar molecules with much desired function for post-synthetic conjugation. To address this need, cyanine dyes were prepared using an alternative synthesis protocol. All studied compounds showed considerabl…
HAWC Gamma-Ray survey, AGNs at TeV photon energies
2022
The High Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory continuously detects TeV photons and particles within its large field of view, accumulating every day a deeper exposure of two-thirds of the sky. We analyzed 1523days of HAWC live data acquired over four and a half years, in a follow-up analysis of 138 nearby (z<0.3) active galactic nuclei from the Third Catalog of Hard Fermi-LAT sources culminating within 40{deg} of the zenith at Sierra Negra, the HAWC site. This search for persistent TeV emission used a maximum- likelihood analysis assuming intrinsic power-law spectra attenuated by pair production of gamma-ray photons with the extragalactic background light. HAWC clearly detec…
TANAMI II. Additional sources
2018
TANAMI is a multiwavelength program monitoring active galactic nuclei (AGN) south of -30{deg} declination including high-resolution Very Long Baseline Interferometry (VLBI) imaging, radio, optical/UV, X-ray and {gamma}-ray studies. We have previously published first-epoch 8.4GHz VLBI images of the parsec-scale structure of the initial sample. In this paper, we present images of 39 additional sources. The full sample comprises most of the radio- and {gamma}-ray brightest AGN in the southern quarter of the sky, overlapping with the region from which high-energy (>100TeV) neutrino events have been found. We characterize the parsec-scale radio properties of the jets and compare with the quasi-s…
TANAMI monitoring of Centaurus A.
2015
Centaurus A (Cen A) is the closest radio-loud active galactic nucleus. Very Long Baseline Interferometry (VLBI) enables us to study the spectral and kinematic behavior of the radio jet-counterjet system on milliarcsecond scales, providing essential information for jet emission and propagation models. In the framework of the TANAMI monitoring, we investigate the kinematics and complex structure of Cen A on subparsec scales. We have been studying the evolution of the central parsec jet structure of Cen A for over 3.5-years. The proper motion analysis of individual jet components allows us to constrain jet formation and propagation and to test the proposed correlation of increased high-energy …
The gNLS1 galaxy PKS 2004-447. VLBI images
2016
Gamma-ray-detected radio-loud narrow-line Seyfert 1 (g-NLS1) galaxies constitute a small but interesting sample of the g-ray-loud AGN. The radio-loudest g-NLS1 known, PKS 2004-447, is located in the southern hemisphere and is monitored in the radio regime by the multiwavelength monitoring programme TANAMI. We aim for the first detailed study of the radio morphology and long-term radio spectral evolution of PKS 2004-447, which are essential for understanding the diversity of the radio properties of g-NLS1s. The TANAMI VLBI monitoring program uses the Australian Long Baseline Array (LBA) and telescopes in Antarctica, Chile, New Zealand, and South Africa to monitor the jets of radio-loud activ…
Sample of weak blazars at mas resolution
2015
We started a follow-up investigation of the "Deep X-ray Radio Blazar Survey" objects with declination >-10{deg} to better understand the blazar phenomenon. We undertook a survey with the European Very Long Baseline Interferometry Network at 5GHz to make the first images of a complete sample of weak blazars, aiming at a follow-up comparison between high- and low-power samples of blazars. We observed 87 sources with the EVN at 5GHz during the period October 2009 to May 2013. The observations were correlated at the Max-Planck-Institut fuer Radioastronomie and at the Joint Institute for VLBI in Europe. The correlator output was analysed using both the AIPS and DIFMAP software packages. All of t…
Backbending in the pear-shaped 223(90)Th nucleus: Evidence of a high-spin octupole to quadrupole shape transition in the actinides
2017
International audience; Relatively neutron-rich thorium isotopes lie at the heart of a nuclear region of nuclei exhibiting octupole correlation effects. The detailed level structure of Th223 has been investigated in measurements of γ radiation following the fusion-evaporation channel of the Pb208(O18,3n)Th223 reaction at 85 MeV beam energy. The level structure has been extended up to spin 49/2, and 33 new γ rays have been added using triple-γ coincidence data. The spins and parities of the newly observed states have been confirmed by angular distribution ratios. In addition to the two known yrast bands based on a K=5/2 configuration, a non-yrast band has been established up to spin 35/2. We…
Heterogeneity within and between primary colorectal carcinomas and matched metastases as revealed by analysis of Ki-ras and p53 mutations
2004
Analysis of the genetic status of Ki-ras and p53 in primary colorectal carcinomas and matched colorectal liver metastasis from 30 patients reveals an overall heterogeneity both within and between the two tumoral tissues. Both genes were found mutated with a similar frequency in both tissues; however, identical mutations in primary tumor and matched metastasis were found less frequently in the case of the Ki-ras than the p53 gene. Only in three cases the same p53 and Ki-ras mutations found in the primary tumor were found also in the metastasis. In several metastatic specimens the DNA bearing a mutation detected also in the primary tumor appears significantly less abundant than the wild-type …