| 1. |
- Schael, S, et al.
(author)
-
Precision electroweak measurements on the Z resonance
- 2006
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In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Research review (peer-reviewed)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Schael, S., et al.
(author)
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Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP
- 2013
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In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 532:4, s. 119-244
-
Research review (peer-reviewed)abstract
- Electroweak measurements performed with data taken at the electron positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb(-1) collected by the four LEP experiments ALEPH, DELPHI, 13 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose Einstein correlations between the two W decay systems arising in WW production, are searched for and upper limits on the strength of possible effects are obtained. The data are used to determine fundamental properties of the W boson and the electroweak theory. Among others, the mass and width of the W boson, m(w) and Gamma(w), the branching fraction of W decays to hadrons, B(W -> had), and the trilinear gauge-boson self-couplings g(1)(Z), K-gamma and lambda(gamma), are determined to be: m(w) = 80.376 +/- 0.033 GeV Gamma(w) = 2.195 +/- 0.083 GeV B(W -> had) = 67.41 +/- 0.27% g(1)(Z) = 0.984(-0.020)(+0.018) K-gamma - 0.982 +/- 0.042 lambda(gamma) = 0.022 +/- 0.019. (C) 2013 Elsevier B.V. All rights reserved.
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| 3. |
- Akkoyun, S., et al.
(author)
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AGATA - Advanced GAmma Tracking Array
- 2012
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In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - : Elsevier BV. - 0168-9002 .- 0167-5087 .- 1872-9576. ; 668, s. 26-58
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Journal article (peer-reviewed)abstract
- The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation γ-ray spectrometer. AGATA is based on the technique of γ-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a γ ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realisation of γ-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterisation of the crystals was measured and compared with detector- response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximise its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer. © 2011 Elsevier B.V. All rights reserved.
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| 4. |
- Schuller, F., et al.
(author)
-
The SEDIGISM survey: First Data Release and overview of the Galactic structure
- 2021
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In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 500:3, s. 3064-3082
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Journal article (peer-reviewed)abstract
- The SEDIGISM (Structure, Excitation and Dynamics of the Inner Galactic InterstellarMedium) survey used the APEX telescope to map 84 deg(2) of the Galactic plane between l = -60 degrees and +31 degrees in several molecular transitions, including (CO)-C-13(2 - 1) and (CO)-O-18(2 - 1), thus probing the moderately dense (similar to 10(3) cm(-3)) component of the interstellar medium. With an angular resolution of 30 arcsec and a typical 1 sigma sensitivity of 0.8-1.0K at 0.25 km s(-1) velocity resolution, it gives access to a wide range of structures, from individual star-forming clumps to giant molecular clouds and complexes. The coverage includes a good fraction of the first and fourth Galactic quadrants, allowing us to constrain the large-scale distribution of cold molecular gas in the inner Galaxy. In this paper, we provide an updated overview of the full survey and the data reduction procedures used. We also assess the quality of these data and describe the data products that are being made publicly available as part of this First Data Release (DR1). We present integrated maps and position-velocity maps of the molecular gas and use these to investigate the correlation between the molecular gas and the large-scale structural features of the Milky Way such as the spiral arms, Galactic bar and Galactic Centre. We find that approximately 60 per cent of the molecular gas is associated with the spiral arms and these appear as strong intensity peaks in the derived Galactocentric distribution. We also find strong peaks in intensity at specific longitudes that correspond to the Galactic Centre and well-known star-forming complexes, revealing that the 13CO emission is concentrated in a small number of complexes rather than evenly distributed along spiral arms.
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| 5. |
- Duarte-Cabral, A., et al.
(author)
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The SEDIGISM survey: Molecular clouds in the inner Galaxy
- 2021
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In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 500:3, s. 3027-3049
-
Research review (peer-reviewed)abstract
- We use the 13CO(2-1) emission from the SEDIGISM (Structure, Excitation, and Dynamics of the Inner Galactic InterStellar Medium) high-resolution spectral-line survey of the inner Galaxy, to extract the molecular cloud population with a large dynamic range in spatial scales, using the Spectral Clustering for Interstellar Molecular Emission Segmentation (SCIMES) algorithm. This work compiles a cloud catalogue with a total of 10 663 molecular clouds, 10 300 of which we were able to assign distances and compute physical properties. We study some of the global properties of clouds using a science sample, consisting of 6664 well-resolved sources and for which the distance estimates are reliable. In particular, we compare the scaling relations retrieved from SEDIGISM to those of other surveys, and we explore the properties of clouds with and without high-mass star formation. Our results suggest that there is no single global property of a cloud that determines its ability to form massive stars, although we find combined trends of increasing mass, size, surface density, and velocity dispersion for the sub-sample of clouds with ongoing high-mass star formation. We then isolate the most extreme clouds in the SEDIGISM sample (i.e. clouds in the tails of the distributions) to look at their overall Galactic distribution, in search for hints of environmental effects. We find that, for most properties, the Galactic distribution of the most extreme clouds is only marginally different to that of the global cloud population. The Galactic distribution of the largest clouds, the turbulent clouds and the high-mass star-forming clouds are those that deviate most significantly from the global cloud population. We also find that the least dynamically active clouds (with low velocity dispersion or low virial parameter) are situated further afield, mostly in the least populated areas. However, we suspect that part of these trends may be affected by some observational biases (such as completeness and survey limitations), and thus require further follow up work in order to be confirmed.
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| 6. |
- Wang, X., et al.
(author)
-
Collective structures up to spin ∼ 65h in the N 90 isotones 158Er and 157Ho
- 2012
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In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 381:1
-
Journal article (peer-reviewed)abstract
- A new collective band with high dynamic moment of inertia in 158Er at spins beyond band termination has been found in addition to the two previously reported ones. The measured transition quadrupole moments (Qt) of these three bands are very similar. These three bands have been suggested to possess a triaxial strongly deformed shape, based on comparisons with calculations using the cranked Nilsson-Strutinsky model and with tilted axis cranking calculations using the Skyrme-Hartree-Fock model. In addition, three collective bands with similar high dynamic moments of inertia, tentatively assigned to 157Ho, have been observed. Thus, it is suggested that all these structures share a common underlying character and that they are most likely associated with triaxial strongly deformed minima which are predicted to be close to the yrast line at spin 50 - 70h.
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| 7. |
- Adam, R. M., et al.
(author)
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The XXL Survey: LI. Pressure profile and Y SZ -M scaling relation in three low-mass galaxy clusters at z∼1 observed with NIKA2
- 2024
-
In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 684
-
Journal article (peer-reviewed)abstract
- Context. The thermodynamical properties of the intracluster medium (ICM) are driven by scale-free gravitational collapse, but they also reflect the rich astrophysical processes at play in galaxy clusters. At low masses (∼1014M) and high redshift (z≳1), these properties remain poorly constrained, observationally speaking, due to the difficulty in obtaining resolved and sensitive data. Aims. We aim to investigate the inner structure of the ICM as seen through the Sunyaev-Zel’dovich (SZ) effect in this regime of mass and redshift. We focused on the thermal pressure profile and the scaling relation between SZ flux and mass, namely the YSZ-M scaling relation. Methods. The three galaxy clusters XLSSC 072 (z=1.002), XLSSC 100 (z=0.915), and XLSSC 102 (z=0.969), with M500∼2×1014M, were selected from the XXL X-ray survey and observed with the NIKA2 millimeter camera to image their SZ signal. XMM-Newton X-ray data were used as a complement to the NIKA2 data to derive masses based on the YX-M relation and the hydrostatic equilibrium. Results. The SZ images of the three clusters, along with the X-ray and optical data, indicate dynamical activity related to merging events. The pressure profile is consistent with that expected for morphologically disturbed systems, with a relatively flat core and a shallow outer slope. Despite significant disturbances in the ICM, the three high-redshift low-mass clusters follow the YSZ-M relation expected from standard evolution remarkably well. Conclusions. These results indicate that the dominant physics that drives cluster evolution is already in place by z∼1, at least for systems with masses above M500∼1014M.
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| 8. |
- Simpson, J., et al.
(author)
-
Evolution of structure and shapes in Er 158 to ultrahigh spin
- 2023
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In: Physical Review C. - 2469-9985. ; 107:5
-
Journal article (peer-reviewed)abstract
- The level structure of Er158 has been studied using the Gammasphere spectrometer via the Cd114(Ca48,4n) reaction at 215 MeV with both thin (self-supporting) and thick (backed) targets. The level scheme has been considerably extended with more than 200 new transitions and six new rotational structures, including two strongly coupled high-K bands. Configuration assignments for the new structures are based on their observed alignments, B(M1)/B(E2) ratios of reduced transition probabilities, excitation energies, and comparisons with neighboring nuclei and theoretical calculations. With increasing angular momentum, this nucleus exhibits Coriolis-induced alignments of both neutrons and protons before it then undergoes a rotation-induced transition from near-prolate collective rotation to a noncollective oblate configuration. This transition occurs via the mechanism of band termination around spin 45ħ in three rotational structures. Two distinct lifetime branches, consistent with the crossing of a collective "fast"rotational structure by an energetically favored "slow"terminating sequence, are confirmed for the positive-parity states, and similar behavior is established in the negative-parity states. Weak-intensity, high-energy transitions are observed to feed into the terminating states. At the highest spins, three collective bands with high dynamic moments of inertia and large quadrupole moments were identified. These bands are interpreted as triaxial strongly deformed structures and mark a return to collectivity at ultrahigh spin.
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| 9. |
- Wang, X., et al.
(author)
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Quadrupole moments of collective structures up to spin similar to 65(h)over-bar in Er-157 and Er-158: A challenge for understanding triaxiality in nuclei
- 2011
-
In: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 702:2-3, s. 127-130
-
Journal article (peer-reviewed)abstract
- The transition quadrupole moments. Q(t), of four weakly populated collective bands up to spin similar to 65h in Er-157,Er-158 have been measured to be similar to II eb demonstrating that these sequences are associated with large deformations. However, the data are inconsistent with calculated values from cranked Nilsson-Strutinsky calculations that predict the lowest energy triaxial shape to be associated with rotation about the short principal axis. The data appear to favor either a stable triaxial shape rotating about the intermediate axis or, alternatively, a triaxial shape with larger deformation rotating about the short axis. These new results challenge the present understanding of triaxiality in nuclei. (C) 2011 Elsevier B.V. All rights reserved.
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| 10. |
- Mustafa, M., et al.
(author)
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Diverse collective excitations in Er-159 up to high spin
- 2011
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 84:5
-
Journal article (peer-reviewed)abstract
- A spectroscopic investigation of the gamma decays from excited states in Er-159 has been performed to study the changing structural properties exhibited as ultrahigh spins (I > 60 (h) over bar) are approached. The nucleus of Er-159 was populated by the reaction Cd-116(Ca-48, 5n gamma) at a beam energy of 215 MeV, and the resulting gamma decays were studied using the Gammasphere spectrometer. New rotational bands and extensions to existing sequences were observed, which are discussed in terms of the cranked shell model, revealing a diverse range of quasiparticle configurations. At spins around 50 (h) over bar, there is evidence for a change from dominant prolate collective motion at the yrast line to oblate non-collective structures via the mechanism of band termination. A possible strongly deformed triaxial band occurs at these high spins, which indicates collectivity beyond 50 (h) over bar. The high-spin data are interpreted within the framework of cranked Nilsson-Strutinsky calculations.
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| 11. |
- Ollier, J., et al.
(author)
-
Structure changes in Er-160 from low to ultrahigh spin
- 2011
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 83:4
-
Journal article (peer-reviewed)abstract
- A spectroscopic investigation of the gamma decays from excited states in Er-160 has been performed in order to study the changing structural properties exhibited from low spin up toward ultrahigh spin (I similar to 60 h). The nucleus Er-160 was populated by the reaction Cd-116(Ca-48,4n gamma) at a beam energy of 215 MeV, and resulting gamma decays were studied using the Gammasphere spectrometer. New rotational structures and extensions to existing bands were observed, revealing a diverse range of quasiparticle configurations, which are discussed in terms of the cranked shell model. At spins around 50h there is evidence for oblate states close to the yrast line. Three rotational bands that have the characteristics of strongly deformed triaxial structures are observed, marking a return to collectivity at even higher spin. The high-spin data are interpreted within the framework of cranked Nilsson-Strutinsky calculations.
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| 12. |
- Ollier, J., et al.
(author)
-
Ultrahigh-spin spectroscopy of Er-159,Er-160: Observation of triaxial strongly deformed structures
- 2009
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 80:6
-
Journal article (peer-reviewed)abstract
- Three weakly populated high-spin rotational bands associated with the gamma decay of Er-159 and Er-160 were observed in fusion-evaporation reactions involving a beam of Ca-48 at an energy of 215 MeV incident on a Cd-116 target. The gamma decays were detected using the highly efficient Gammasphere spectrometer. The discovery of these bands, which extend discrete-line spectroscopy in these nuclei to ultrahigh spin of similar to 60h, is consistent with recent observations of high-spin collective structures in isotopes of Er, Yb, and Tm around N=90. Cranked Nilsson-Strutinsky calculations suggest that these bands may arise from well-deformed triaxial configurations with either positive or negative gamma deformation.
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| 13. |
- Revill, J. P., et al.
(author)
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Quadrupole moments of coexisting collective shapes at high spin in Er-154
- 2013
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 88:3
-
Journal article (peer-reviewed)abstract
- Four high-spin collective bands have been populated in Er-154(68)86 via the Pd-110(Ti-48, (4)n gamma)Er-154 reaction. Average transition quadrupole moments Q(t) have been measured for three of the bands by using the Doppler-shift attenuation method. The strongest band has a value of Q(t) = 11.0 +/- 1.0 e b, similar to values found recently for four triaxial strongly deformed (TSD) bands in Er-157,Er-158. The second band has a value of Q(t) = 19.5 +/- 3.2 e b, consistent with a predicted axially symmetric superdeformed (SD) shape, similar in deformation to the Dy-152 isotone, and is used as a calibration point. The third, new band has a value of Q(t) = 9.9 +/- 2.2 e b. The results confirm the unexpectedly large Q(t) moments for the favored TSD bands in light erbium isotopes.
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| 14. |
- Revill, J. P., et al.
(author)
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Relative quadrupole moments of exotic shapes at ultrahigh spin in 154Er : Calibrating the TSD/SD puzzle
- 2012
-
In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596.
-
Conference paper (peer-reviewed)abstract
- Transition quadrupole moments, Qt, of two ultrahigh-spin, collective structures in 154Er have been measured for the first time using the Doppler Shift Attenuation Method (DSAM). Data were acquired at the ATLAS accelerator facility of Argonne National Laboratory, using the Gammasphere detector array. A thick, gold-backed 110Pd foil was bombarded by a beam of 48Ti ions at 215 MeV. The Qt for each band was determined from the Doppler shift of gamma rays emitted by the resulting recoil nuclei. The extracted transition quadrupole moments are significantly different in magnitude, suggesting the two structures in 154Er represent distinct exotic nuclear shapes, namely axial superdeformed (SD) with Q t 20 eb, and triaxial strongly deformed (TSD) with Qt ≈ 11 eb. Indeed, the results calibrate the quadrupole moments of TSD bands recently measured in light erbium nuclei, 157,158Er.
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| 15. |
- Riley, M. A., et al.
(author)
-
Strongly Deformed Nuclear Shapes at Ultra-High Spin and Shape Coexistence in N\sim 90 Nuclei
- 2009
-
In: Acta Physica Polonica B. - 0587-4254. ; 40:3, s. 513-522
-
Journal article (peer-reviewed)abstract
- The N similar to 90 region of the nuclear chart has featured prominently as the spectroscopy of nuclei at extreme spin has progressed. This talk will present recent discoveries from investigations of high spin behavior in the N similar to 90 Er, Tm and Yb nuclei utilizing the Gammasphere gamma-ray spectrometer. In particular it will include discussion of the beautiful shape evolution and coexistence observed in these nuclei along with the identification of a remarkable new family of band structures. The latter are very weakly populated rotational sequences with high moment of inertia that bypass the classic terminating configurations near spin 40-50 (h) over bar, marking a return to collectivity that extends discrete gamma-ray spectroscopy to well over 60 (h) over bar. Establishing the nature of the yrast states in these nuclei beyond the oblate band-termination states has been a major goal for the past two decades. Cranking calculations suggest that these new structures most likely represent stable triaxial strongly deformed bands that lie in a valley of favored shell energy in deformation and particle-number space.
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| 16. |
- Cleland, J. G. F., et al.
(author)
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Beta-blockers for heart failure with reduced, mid-range, and preserved ejection fraction: an individual patient-level analysis of double-blind randomized trials
- 2018
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In: European Heart Journal. - : Oxford University Press (OUP). - 0195-668X .- 1522-9645. ; 39:1, s. 26-35
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Journal article (peer-reviewed)abstract
- Aims Recent guidelines recommend that patients with heart failure and left ventricular ejection fraction (LVEF) 40-49% should be managed similar to LVEF >= 50%. We investigated the effect of beta-blockers according to LVEF in double-blind, randomized, placebo-controlled trials. Methods and results Individual patient data meta-analysis of 11 trials, stratified by baseline LVEF and heart rhythm (Clinicaltrials.gov: NCT0083244; PROSPERO: CRD42014010012). Primary outcomes were all-cause mortality and cardiovascular death over 1.3 years median follow-up, with an intention-to-treat analysis. For 14 262 patients in sinus rhythm, median LVEF was 27% (interquartile range 21-33%), including 575 patients with LVEF 40-49% and 244 >= 50%. Beta-blockers reduced all-cause and cardiovascular mortality compared to placebo in sinus rhythm, an effect that was consistent across LVEF strata, except for those in the small subgroup with LVEF >= 50%. For LVEF 40-49%, death occurred in 21/292 [7.2%] randomized to beta-blockers compared to 35/283 [12.4%] with placebo; adjusted hazard ratio (HR) 0.59 [95% confidence interval (CI) 0.34-1.03]. Cardiovascular death occurred in 13/292 [4.5%] with beta-blockers and 26/283 [9.2%] with placebo; adjusted HR 0.48 (95% CI 0.24-0.97). Over a median of 1.0 years following randomization (n = 4601), LVEF increased with beta-blockers in all groups in sinus rhythm except LVEF >= 50%. For patients in atrial fibrillation at baseline (n = 3050), beta-blockers increased LVEF when < 50% at baseline, but did not improve prognosis. Conculations Beta-blockers improve LVEF and prognosis for patients with heart failure in sinus rhythm with a reduced LVEF. The data are most robust for LVEF < 40%, but similar benefit was observed in the subgroup of patients with LVEF 40-49%.
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| 17. |
- Gaffney, L. P., et al.
(author)
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Studies of pear-shaped nuclei using accelerated radioactive beams
- 2013
-
In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 497:7448, s. 199-204
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Journal article (peer-reviewed)abstract
- There is strong circumstantial evidence that certain heavy, unstable atomic nuclei are 'octupole deformed', that is, distorted into a pear shape. This contrasts with the more prevalent rugby-ball shape of nuclei with reflection-symmetric, quadrupole deformations. The elusive octupole deformed nuclei are of importance for nuclear structure theory, and also in searches for physics beyond the standard model; any measurable electric-dipole moment (a signature of the latter) is expected to be amplified in such nuclei. Here we determine electric octupole transition strengths (a direct measure of octupole correlations) for short-lived isotopes of radon and radium. Coulomb excitation experiments were performed using accelerated beams of heavy, radioactive ions. Our data on Rn-220 and Ra-224 show clear evidence for stronger octupole deformation in the latter. The results enable discrimination between differing theoretical approaches to octupole correlations, and help to constrain suitable candidates for experimental studies of atomic electric-dipole moments that might reveal extensions to the standard model.
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| 18. |
- Procter, M. G., et al.
(author)
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Anomalous transition strength in the proton-unbound nucleus (109)(53)I56
- 2011
-
In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 704:3, s. 118-122
-
Journal article (peer-reviewed)abstract
- A lifetime measurement has been made for the first excited 11/2(+) state in the proton-unbound nucleus (109)(53)I56 using the recoil-distance Doppler-shift method in conjunction with recoil-proton tagging. The experimental reduced transition probability is considerably smaller than the prediction of theoretical shell-model calculations using the CD-Bonn nucleon-nucleon potential. The discrepancy between the theoretical and experimental reduced transition strengths in this work most likely arises from the inability of the current shell-model calculations to accurately account for the behavior of the unbound nuclear states.
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| 19. |
- Procter, M. G., et al.
(author)
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Lifetime measurement in the proton-unbound nucleus 109I
- 2011
-
In: AIP Conf. Proc.. - : AIP. - 9780735409835 ; , s. 105-110
-
Conference paper (peer-reviewed)abstract
- The Recoil-Distance Doppler-shift method has been combined with Recoil-Decay Tagging for the first time to measure a lifetime in the proton-unbound nucleus 109I. The lifetime value was determined using the Differential Decay-Curve method in singles mode. The result has been compared to theoretical shell-model calculations in order to better understand the nature of unbound valence nucleons at the proton drip line.
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| 20. |
- Scheck, M., et al.
(author)
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Do nuclei go pear-shaped? Coulomb excitation of Rn-220 and Ra-224 at REX-ISOLDE (CERN)
- 2015
-
In: Cgs15 - Capture Gamma-ray Spectroscopy and Related Topics. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 93, s. 01038-01038
-
Conference paper (peer-reviewed)abstract
- The IS475 collaboration conducted Coulomb-excitation experiments with post-accelerated radioactive Rn-220 and Ra-224 beams at the REX-ISOLDE facility. The beam particles (E-beam: 2.83 MeV/u) were Coulomb excited using Ni-60, Cd-14, and Sn-120 scattering targets. De-excitation gamma-rays were detected employing the Miniball array and scattered particles were detected in a silicon detector. Exploiting the Coulomb-excitation code GOSIA for each nucleus several matrix elements could be obtained from the measured gamma-ray yields. The extracted < 3 parallel to E3 parallel to 0(+)> matrix element allows for the conclusion that, while Rn-220 represents an octupole vibrational system, Ra-224 has already substantial octupole correlations in its ground state. This finding has i(m)plications for the search of CP-violating Schiff moments in the atomic systems of the adjacent odd-mass nuclei.
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| 21. |
- Paul, E. S., et al.
(author)
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Loss of collectivity in the transitional Er-156 nucleus at high spin
- 2009
-
In: Physical Review C (Nuclear Physics). - 0556-2813. ; 79:4
-
Journal article (peer-reviewed)abstract
- The Cd-114(Ca-48, 6n gamma) reaction at 215 MeV has been investigated using the Gammasphere spectrometer to study the high-spin structure of the nucleus Er-156(68)88. Many new transitions have been established along with 68 definitive spin-parity level assignments from a high-fold angular-distribution analysis. In addition, absolute B(M 1) and B(E 1) strengths have been inferred from measured gamma-ray branching ratios. Strong B(E 1) strength (10(-3) W.u.) is discussed in terms of possible octupole collectivity at low spin. At high spin, this nucleus undergoes a Coriolis-induced shape transition from a prolate state of collective rotation to a noncollective, triaxial-oblate configuration. The yrast positive-parity structure ultimately terminates in an energetically favored oblate state at I-pi = 42(+). Several weak high-energy gamma-ray transitions have been discovered that feed this favored state. State-of-the-art cranked Nilsson-Strutinsky calculations are used to interpret the high-spin behavior of Er-156 and comparisons are made with other N = 88 isotones.
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| 22. |
- Khan, N. K., et al.
(author)
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Prevalence of ECG abnormalities in an international survey of patients with suspected or confirmed heart failure at death or discharge
- 2007
-
In: European journal of heart failure. - : Wiley. - 1388-9842. ; 9:5, s. 491-501
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Journal article (peer-reviewed)abstract
- BACKGROUND: Most patients suspected of having heart failure (HF) will get a 12-lead electrocardiogram (ECG) but its utility for excluding HF or assisting in its management has rarely been investigated. METHODS: The EuroHeart Failure survey identified 11,327 patients hospitalised with a suspected diagnosis of HF from 115 hospitals in 24 countries. ECGs were obtained from 9315 patients, of whom 5934 had cardiac imaging tests. The utility of the ECG was assessed for excluding or diagnosing major structural heart disease (MSHD) or major left ventricular systolic dysfunction (MLVSD) and for therapeutic decision making. FINDINGS: MSHD was present in 70% and MLVSD in 54% of patients overall but in only 21% and 5%, respectively, if the ECG was entirely normal. However, <2% of patients had a normal ECG. No single ECG characteristic identified a probability <25% of MSHD or <20% of MLVSD. Patients with QRS width >/=120 ms or anterior pathological Q-waves had a probability >80% of MSHD and >70% of MLVSD. Diagnostic models suggested that electrocardiographic criteria alone were not accurate for the diagnosis or exclusion of important heart disease in this population. However, 2468 patients (42%) had an electrocardiographic finding that should be used to guide the choice of therapy. CONCLUSIONS: A normal ECG is rare in patients with suspected HF but has limited diagnostic value in this setting. The ECG has an important role in guiding therapy.
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