| 1. |
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| 2. |
- Ahrens, J., et al.
(författare)
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Calibration and survey of AMANDA with the SPASE detectors
- 2004
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 522:3, s. 347-359
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Tidskriftsartikel (refereegranskat)abstract
- We report on the analysis of air showers observed in coincidence by the Antarctic Muon and Neutrino detector array (AMANDA-B10) and the South Pole Air Shower Experiment (SPASE-1 and SPASE-2). We discuss the use of coincident events for calibration and survey of the deep AMANDA detector as well as the response of AMANDA to muon bundles. This analysis uses data taken during 1997 when both SPASE-1 and SPASE-2 were in operation to provide a stereo view of AMANDA. © 2003 Elsevier B.V. All rights reserved.
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| 3. |
- Ahrens, J., et al.
(författare)
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Measurement of the cosmic ray composition at the knee with the SPASE-2/AMANDA-B10 detectors
- 2004
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Ingår i: Astroparticle physics. - : Elsevier. - 0927-6505 .- 1873-2852. ; 21:6, s. 565-581
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Tidskriftsartikel (refereegranskat)abstract
- The mass composition of high-energy cosmic rays at energies above 1015 eV can provide crucial information for the understanding of their origin. Air showers were measured simultaneously with the SPASE-2 air shower array and the AMANDA-B10 Cherenkov telescope at the South Pole. This combination has the advantage to sample almost all high-energy shower muons and is thus a new approach to the determination of the cosmic ray composition. The change in the cosmic ray mass composition was measured versus existing data from direct measurements at low energies. Our data show an increase of the mean log atomic mass 〈lnA〉 by about 0.8 between 500 TeV and 5 PeV. This trend of an increasing mass through the "knee" region is robust against a variety of systematic effects. © 2004 Elsevier B.V. All rights reserved.
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| 4. |
- Ahrens, J., et al.
(författare)
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Limits on diffuse fluxes of high energy extraterrestrial neutrinos with the AMANDA-B10 detector
- 2003
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Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 90:25, s. 2511011-2511015
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Tidskriftsartikel (refereegranskat)abstract
- A report on the limits, which could be placed on diffuse fluxes of high energy extraterrestrial neutrinos, was presented. The incorporation of neutrino oscillations was necessary for interpreting the limits in terms of the flux from a cosmological distributions of sources. The energetic accelerated environments were presented as the sources of high energy extraterrestrial neutrinos.
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| 5. |
- Ahrens, J., et al.
(författare)
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Muon track reconstruction and data selection techniques in AMANDA
- 2004
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 524:1-3, s. 169-194
-
Tidskriftsartikel (refereegranskat)abstract
- The Antarctic Muon And Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope operating at the geographic South Pole. It is a lattice of photo-multiplier tubes buried deep in the polar ice between 1500 and 2000 m. The primary goal of this detector is to discover astrophysical sources of high-energy neutrinos. A high-energy muon neutrino coming through the earth from the Northern Hemisphere can be identified by the secondary muon moving upward through the detector. The muon tracks are reconstructed with a maximum likelihood method. It models the arrival times and amplitudes of Cherenkov photons registered by the photo-multipliers. This paper describes the different methods of reconstruction, which have been successfully implemented within AMANDA. Strategies for optimizing the reconstruction performance and rejecting background are presented. For a typical analysis procedure the direction of tracks are reconstructed with about 2° accuracy. © 2004 Elsevier B.V. All rights reserved.
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| 6. |
- Ahrens, J., et al.
(författare)
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Observation of high energy atmospheric neutrinos with the Antarctic muon and neutrino detector array
- 2002
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Ingår i: Physical Review D. - : American Physical Society. - 1550-7998 .- 1550-2368. ; 66:1, s. 120051-1200520
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Tidskriftsartikel (refereegranskat)abstract
- The Antarctic muon and neutrino detector array (AMANDA) began collecting data with ten strings in 1997. Results from the first year of operation are presented. Neutrinos coming through the Earth from the Northern Hemisphere are identified by secondary muons moving upward through the array. Cosmic rays in the atmosphere generate a background of downward moving muons, which are about 106 times more abundant than the upward moving muons. Over 130 days of exposure, we observed a total of about 300 neutrino events. In the same period, a background of 1.05 × 109 cosmic ray muon events was recorded. The observed neutrino flux is consistent with atmospheric neutrino predictions. Monte Carlo simulations indicate that 90% of these events lie in the energy range 66 GeV to 3.4 TeV. The observation of atmospheric neutrinos consistent with expectations establishes AMANDA-B10 as a working neutrino telescope.
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| 7. |
- Ahrens, J., et al.
(författare)
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Physics and operation of the AMANDA-II high energy neutrino telescope
- 2002
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Ingår i: Proceedings of the SPIE - The International Society for Optical Engineering 2003. - : Institution of Electrical Engineers (IEE). ; , s. 79-91
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Konferensbidrag (refereegranskat)abstract
- This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-B10, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we focus on the search for continuous emission from astrophysical point sources and the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
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| 8. |
- Ahrens, J., et al.
(författare)
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Results from the AMANDA telescope
- 2003
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Ingår i: Nuclear Physics A. - : Elsevier. - 0375-9474 .- 1873-1554. ; 721, s. C545-C548
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Tidskriftsartikel (refereegranskat)abstract
- We present results from the AMANDA high energy neutrino telescope located at the South Pole. They include measurements of the atmospheric neutrino flux, search for UHE point sources, and diffuse sources producing electromagnetic/hadronic showers at the detector or close to it.
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| 9. |
- Ahrens, J., et al.
(författare)
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Search for Extraterrestrial Point Sources of Neutrinos with AMANDA-II
- 2004
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 92:7, s. 711021-711025
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Tidskriftsartikel (refereegranskat)abstract
- The results of a search for point sources of high energy neutrinos in the northern hemisphere were presented using AMANDA-II data collected in the year 2000. The results included the flux limits on several active-galactic-nuclei blazars, microquasars, magnetars, and other candidate neutrino sources. A search for excesses above a random background of cosmic ray induced atmospheric neutrinos and misreconstructed downgoing cosmic-rays muons, which revealed no statistically significant neutrino point sources was also presented. It was shown that AMANDA-II had achieved the sensitivity required to probe known TeV γ-ray sources such as the blazar Markarian 501 in its 1997 flaring state at a level where neutrino and γ-ray fluxes were equal.
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| 10. |
- Ahrens, J., et al.
(författare)
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Search for supernova neutrino bursts with the AMANDA detector
- 2001
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Ingår i: Astroparticle physics. - : Elsevier. - 0927-6505 .- 1873-2852. ; 16:4, s. 345-359
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Tidskriftsartikel (refereegranskat)abstract
- The core collapse of a massive star in the Milky Way will produce a neutrino burst, intense enough to be detected by existing underground detectors. The AMANDA neutrino telescope located deep in the South Pole ice can detect MeV neutrinos by a collective rate increase in all photo-multipliers on top of dark noise. The main source of light comes from positrons produced in the CC reaction of anti-electron neutrinos on free protons ve + p → e+ + n. This paper describes the first supernova search performed on the full sets of data taken during 1997 and 1998 (215 days of live time) with 302 of the detector's optical modules. No candidate events resulted from this search. The performance of the detector is calculated, yielding a 70% coverage of the galaxy with one background fake per year with 90% efficiency for the detector configuration under study. An upper limit at the 90% c.l. on the rate of stellar collapses in the Milky Way is derived, yielding 4.3 events per year. A trigger algorithm is presented and its performance estimated. Possible improvements of the detector hardware are reviewed.
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| 11. |
- Andrés, E. C., et al.
(författare)
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The AMANDA neutrino telescope
- 1999
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Ingår i: Nuclear physics B, Proceedings supplements. - 0920-5632 .- 1873-3832. ; 77:1-3, s. 474-485
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Tidskriftsartikel (refereegranskat)abstract
- With an effective telescope area of order 104 m2 for TeV neutrinos, a threshold near ∼50 GeV and a pointing accuracy of 2.5 degrees per muon track, the AMANDA detector represents the first of a new generation of high energy neutrino telescopes, reaching a scale envisaged over 25 years ago. We describe early results on the calibration of natural deep ice as a particle detector as well as on AMANDA's performance as a neutrino telescope.
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| 12. |
- Andrés, E., et al.
(författare)
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Observation of high-energy neutrinos using Čerenkov detectors embedded deep in Antarctic ice
- 2001
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 410:6827, s. 441-443
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Tidskriftsartikel (refereegranskat)abstract
- Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova2, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water3,4 or ice5. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations1.
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| 13. |
- Andrés, E., et al.
(författare)
-
Recent results from AMANDA
- 2001
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Ingår i: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 16:1C, s. 1013-1015
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Tidskriftsartikel (refereegranskat)abstract
- We present results based on data taken in 1997 with the 302-PMT Antarctic Muon and Neutrino Detector Array-B10 ("AMANDA-B10") array. Atmospheric neutrinos created in the northern hemisphere are observed indirectly through their charged current interactions which produce relativistic, Cherenkov-light-emitting upgoing muons in the South Pole ice cap. The reconstructed angular distribution of these events is in good agreement with expectation and demonstrates the viability of this ice-based device as a neutrino telescope.
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| 14. |
- Kondo, Y., et al.
(författare)
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First observation of 28 O
- 2023
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 620:7976, s. 965-970
-
Tidskriftsartikel (refereegranskat)abstract
- Subjecting a physical system to extreme conditions is one of the means often used to obtain a better understanding and deeper insight into its organization and structure. In the case of the atomic nucleus, one such approach is to investigate isotopes that have very different neutron-to-proton (N/Z) ratios than in stable nuclei. Light, neutron-rich isotopes exhibit the most asymmetric N/Z ratios and those lying beyond the limits of binding, which undergo spontaneous neutron emission and exist only as very short-lived resonances (about 10−21s), provide the most stringent tests of modern nuclear-structure theories. Here we report on the first observation of 28O and 27O through their decay into 24O and four and three neutrons, respectively. The 28O nucleus is of particular interest as, with the Z = 8 and N = 20 magic numbers1,2, it is expected in the standard shell-model picture of nuclear structure to be one of a relatively small number of so-called ‘doubly magic’ nuclei. Both 27O and 28O were found to exist as narrow, low-lying resonances and their decay energies are compared here to the results of sophisticated theoretical modelling, including a large-scale shell-model calculation and a newly developed statistical approach. In both cases, the underlying nuclear interactions were derived from effective field theories of quantum chromodynamics. Finally, it is shown that the cross-section for the production of 28O from a 29F beam is consistent with it not exhibiting a closed N = 20 shell structure.
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| 15. |
- Kowalski, Marek, et al.
(författare)
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Physics results from the AMANDA neutrino detector
- 2001
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Ingår i: Proceedings of Science. - 1824-8039. ; HEP2001
-
Tidskriftsartikel (refereegranskat)abstract
- In the winter season of 2000, the AMANDA (Antarctic Muon And NeutrinoDetector Array) detector was completed to its nal state. We report on major physicsresults obtained from the AMANDA-B10 detector, as well as initial results of the fullAMANDA-II detector.
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| 16. |
- Ahrens, J., et al.
(författare)
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Results from the Antarctic muon and nuetrino detector array
- 2003
-
Ingår i: Nuclear physics B, Proceedings supplements. - : Elsevier. - 0920-5632 .- 1873-3832. ; 118, s. 371-379
-
Tidskriftsartikel (refereegranskat)abstract
- We show new results from both the older and newer incarnations of AMANDA (AMANDA-B10 and AMANDA-II, respectively). These results demonstrate that AMANDA is a functioning, multipurpose detector with significant physics and astrophysics reach. They include a new higher-statistics measurement of the atmospheric muon neutrino flux and preliminary results from searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, gamma-ray bursters and diffuse sources producing muons in the detector, and diffuse sources producing electromagnetic or hadronic showers in or near the detector.
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| 17. |
- Ahrens, J., et al.
(författare)
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Search for neutrino-induced cascades with the AMANDA detector
- 2003
-
Ingår i: Physical Review D. - : American Physical Society (APS). - 1550-7998 .- 1550-2368. ; 67:1, s. 012003-
-
Tidskriftsartikel (refereegranskat)abstract
- We report on a search for electromagnetic and/or hadronic showers (cascades) induced by a diffuse flux of neutrinos with energies between 5 TeV and 300 TeV from extraterrestrial sources. Cascades may be produced by matter interactions of all flavors of neutrinos, and contained cascades have better energy resolution and afford better background rejection than throughgoing νμ-induced muons. Data taken in 1997 with the AMANDA detector were searched for events with a high-energy cascadelike signature. The observed events are consistent with expected backgrounds from atmospheric neutrinos and catastrophic energy losses from atmospheric muons. Effective volumes for all flavors of neutrinos, which allow the calculation of limits for any neutrino flux model, are presented. The limit on cascades from a diffuse flux of νe+ νμ + ντ+ ν̄e + ν̄μ+ ν̄τ is E2(dΦ/dE)<9.8×10-6 GeV cm-2 s-1 sr-1, assuming a neutrino flavor flux ratio of 1:1:1 at the detector. The limit on cascades from a diffuse flux of νe+ν̄e is E2(dΦ/dE)<6. 5×10-6 GeV cm-2 s-1 sr-1, independent of the assumed neutrino flavor flux ratio. © 2003 The American Physical Society.
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| 18. |
- Ahrens, J., et al.
(författare)
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Search for point sources of high-energy neutrinos with AMANDA
- 2003
-
Ingår i: Astrophysical Journal Letters. - : Institute of Physics (IOP). - 2041-8205 .- 0004-637X .- 1538-4357. ; 583:2 I, s. 1040-1057
-
Tidskriftsartikel (refereegranskat)abstract
- This paper describes the search for astronomical sources of high-energy neutrinos using the AMANDA-B10 detector, an array of 302 photomultiplier tubes used for the detection of Cerenkov light from upward-traveling neutrino-induced muons, buried deep in ice at the South Pole. The absolute pointing accuracy and angular resolution were studied by using coincident events between the AMANDA detector and two independent telescopes on the surface, the GASP air Cerenkov telescope and the SPASE extensive air shower array. Using data collected from 1997 April to October (130.1 days of live time), a general survey of the northern hemisphere revealed no statistically significant excess of events from any direction. The sensitivity for a flux of muon neutrinos is based on the effective detection area for through-going muons. Averaged over the northern sky, the effective detection area exceeds 10,000 m2 for E μ ≈ 10 TeV. Neutrinos generated in the atmosphere by cosmic-ray interactions were used to verify the predicted performance of the detector. For a source with a differential energy spectrum proportional to Eν -2 and declination larger than +40°, we obtain E2(dNν/dE) ≤ 10-6 GeV cm-2 s-1 for an energy threshold of 10 GeV.
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| 19. |
- Andres, E., et al.
(författare)
-
Results from the AMANDA high energy neutrino detector
- 2000
-
Ingår i: Nuclear physics B, Proceedings supplements. - : Elsevier. - 0920-5632 .- 1873-3832. ; 91:1-3, s. 423-430
-
Tidskriftsartikel (refereegranskat)abstract
- This paper briefly summarizes the search for astronomical sources of high-energy neutrinos using the AMANDA-B10 detector. The complete data set from 1997 was analyzed. For Eμ > 10 TeV, the detector exceeds 10,000 m2 in effective area between declinations of 25 and 90 degrees. Neutrinos generated in the atmosphere by cosmic ray interactions were used to verify the overall sensitivity of the detector. The absolute pointing accuracy and angular resolution has been confirmed by the analysis of coincident events between the SPASE air shower array and the AMANDA detector. Preliminary flux limits from point source candidates are presented. For declinations larger than +45 degrees, our results compare favorably to existing limits for sources in the Southern sky. We also present the current status of the searches for high energy neutrino emission from diffusely distributed sources, GRBs, and WIMPs from the center of the earth.
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| 20. |
- Bai, X., et al.
(författare)
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Status of the Neutrino Telescope AMANDA : Monopoles and WIMPS
- 2001
-
Ingår i: Dark Matter in Astro- and Particle Physics. - Berlin, Heidelberg : Springer. - 9783642626081 ; , s. 699-706
-
Konferensbidrag (refereegranskat)abstract
- The neutrino telescope AMANDA has been set up at the geographical South Pole as first step to a neutrino telescope of the scale of one cubic kilometer, which is the canonical size for a detector sensitive to neutrinos from Active Galactic Nuclei (AGN), Gamma Ray Bursts (GRB) and Topological Defects (TD). The location and depth in which the detector is installed is given by the requirement to detect neutrinos by the Cherenkov light produced by their reaction products and to keep the background due to atmospheric muons as small as possible. However, a detector optimized for this purpose is also capable to detect the bright Cherenkov light from relativistic Monopoles and neutrino signals from regions with high gravitational potential, where WIMPS are accumulated and possibly annihilate. Both hypothetical particles might contribute to the amount of dark matter. Therefore here a report about the status of the experiment (autumn 2000) and about the status of the search for these particles with the AMANDA B10 sub-detector is given.
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| 21. |
- Edsjö, Joakim, et al.
(författare)
-
WIMP searches with AMANDA-B10
- 2001
-
Ingår i: The Identification Of Dark Matter. - : World Scientific. - 9789810246020 ; , s. 499-505
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 22. |
- Ilieva, S., et al.
(författare)
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Coulomb excitation of neutron-rich Cd isotopes
- 2014
-
Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 89:1
-
Tidskriftsartikel (refereegranskat)abstract
- The isotopes (122),(124),Cd-126 were studied in a "safe" Coulomb-excitation experiment at the radioactive ion-beam facility REX-ISOLDE at CERN. The reduced transition probabilities B(E2; 0(g. s)(vertical bar) -> 2(1)(+)) and limits for the quadrupole moments of the first 2(+) excited states in the three isotopes were determined. The onset of collectivity in the vicinity of the Z = 50 and N = 82 shell closures is discussed by comparison with shell model and beyond mean-field calculations.
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| 23. |
- Ahrens, J., et al.
(författare)
-
Limits to the muon flux from WIMP annihilation in the center of the Earth with the AMANDA detector
- 2002
-
Ingår i: Physical Review D. - : American Physical Society. - 1550-7998 .- 1550-2368. ; 66:3, s. 032006-
-
Tidskriftsartikel (refereegranskat)abstract
- A search for nearly vertical up-going muon-neutrinos from neutralino annihilations in the center of the Earth has been performed with the AMANDA-B10 neutrino detector. The data collected in 130.1 days of live time in 1997, ∼10 9 events, have been analyzed for this search. No excess over the expected atmospheric neutrino background has been observed. An upper limit at 90% confidence level has been obtained on the annihilation rate of neutralinos in the center of the Earth, as well as the corresponding muon flux limit, both as a function of the neutralino mass in the range 100 GeV-5000 GeV. © 2002 The American Physical Society.
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| 24. |
- Andres, E., et al.
(författare)
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AMANDA : Status, results and future
- 1999
-
Ingår i: Proceedings, 8th International Workshop, Venice, Italy, February 23-26, 1999. Vol. 1, 2. ; , s. 63-79
-
Konferensbidrag (refereegranskat)abstract
- We review the status of the AMANDA neutrino telescope. We present resultsobtained from the four-string prototype array AMANDA-B4 and describe themethods of track reconstruction and neutrino event separation. We give also firstresults of the analysis of the 10-string detector AMANDA-B10, in particular onatmospheric neutrinos and the search for magnetic monopoles. We sketch thefuture schedule on the way to a cube kilometer telescope at the South Pole,ICECUBE.
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| 25. |
- Andres, E., et al.
(författare)
-
The AMANDA neutrino telescope : Principle of operation and first results
- 2000
-
Ingår i: Astroparticle physics. - : Elsevier. - 0927-6505 .- 1873-2852. ; 13:1, s. 1-20
-
Tidskriftsartikel (refereegranskat)abstract
- AMANDA is a high-energy neutrino telescope presently under construction at the geographical South Pole. In the Antarctic summer 1995/96, an array of 80 optical modules (OMs) arranged on 4 strings (AMANDA-B4) was deployed at depths between 1.5 and 2 km. In this paper we describe the design and performance of the AMANDA-B4 prototype, based on data collected between February and November 1996. Monte Carlo simulations of the detector response to down-going atmospheric muon tracks show that the global behavior of the detector is understood. We describe the data analysis method and present first results on atmospheric muon reconstruction and separation of neutrino candidates. The AMANDA array was upgraded with 216 OMs on 6 new strings in 1996/97 (AMANDA-B10), and 122 additional OMs on 3 strings in 1997/98.
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| 26. |
- Bay, R. C., et al.
(författare)
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The AMANDA neutrino telescope and the indirect search for dark matter : AMANDA Colaboration
- 1998
-
Ingår i: Physics reports. - : Elsevier. - 0370-1573 .- 1873-6270. ; 307:1-4, s. 243-252
-
Tidskriftsartikel (refereegranskat)abstract
- With an effective telescope area of order 104m2, a threshold of ~50GeV and a pointing accuracy of 2.5°, the AMANDA detector represents the first of a new generation of high energy neutrino telescopes, reaching a scale envisaged over 25 years ago. We describe its performance, focussing on the capability to detect halo dark matter particles via their annihilation into neutrinos.
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| 27. |
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| 28. |
- Koszorús, Agota, et al.
(författare)
-
Charge radii of exotic potassium isotopes challenge nuclear theory and the magic character of N = 32
- 2021
-
Ingår i: Nature Physics. - : Springer Science and Business Media LLC. - 1745-2481 .- 1745-2473. ; 17:4, s. 439-443
-
Tidskriftsartikel (refereegranskat)abstract
- Nuclear charge radii are sensitive probes of different aspects of the nucleon–nucleon interaction and the bulk properties of nuclear matter, providing a stringent test and challenge for nuclear theory. Experimental evidence suggested a new magic neutron number at N = 32 (refs. 1–3) in the calcium region, whereas the unexpectedly large increases in the charge radii4,5 open new questions about the evolution of nuclear size in neutron-rich systems. By combining the collinear resonance ionization spectroscopy method with β-decay detection, we were able to extend charge radii measurements of potassium isotopes beyond N = 32. Here we provide a charge radius measurement of 52K. It does not show a signature of magic behaviour at N = 32 in potassium. The results are interpreted with two state-of-the-art nuclear theories. The coupled cluster theory reproduces the odd–even variations in charge radii but not the notable increase beyond N = 28. This rise is well captured by Fayans nuclear density functional theory, which, however, overestimates the odd–even staggering effect in charge radii. These findings highlight our limited understanding of the nuclear size of neutron-rich systems, and expose problems that are present in some of the best current models of nuclear theory.
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| 29. |
- Wischnewski, R., et al.
(författare)
-
The AMANDA neutrino detector : Status report
- 2000
-
Ingår i: Nuclear physics B, Proceedings supplements. - 0920-5632 .- 1873-3832. ; 85:1-3, s. 141-145
-
Tidskriftsartikel (refereegranskat)abstract
- The first stage of the AMANDA High Energy Neutrino Detector at the South Pole, the 302 PMT array AMANDA-B10, is taking data since 1997. We describe results on atmospheric neutrinos, limits on indirect WIMP detection, seasonal muon flux variation, relativistic monopole flux limits, a search for gravitational collapse neutrinos, and a depth scan of the optical ice properties. The next stage 19-string detector AMANDA-II with ∼650 PMTs will be completed in spring 2000.
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| 30. |
- Wischnewski, R., et al.
(författare)
-
The AMANDA neutrino detector
- 1999
-
Ingår i: Nuclear physics B, Proceedings supplements. - : Elsevier. - 0920-5632 .- 1873-3832. ; 75:1-2, s. 412-414
-
Tidskriftsartikel (refereegranskat)abstract
- The first stage of the AMANDA High Energy Neutrino Detector at the South Pole, the 302 PMT array AMANDA-B with an expected effective area for TeV neutrinos of ∼ 104 m2, has been taking data since 1997. Progress with calibration, investigation of ice properties, as well as muon and neutrino data analysis are described. The next stage 20-string detector AMANDA-II with ∼800 PMTs will be completed in spring 2000.
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| 31. |
- Adolph, C, et al.
(författare)
-
Measurement of the eta -> 3 pi(0) Dalitz plot distribution with the WASA detector at COSY
- 2009
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 677:1-2, s. 24-29
-
Tidskriftsartikel (refereegranskat)abstract
- In the first production run of the WASA experiment at COSY, the eta decay into three neutral pions was measured in proton-proton interactions at a proton beam kinetic energy of 1.4 GeV. The Dalitz plot of the three pious was Studied using 1.2 x 10(5) fully reconstructed events. and the quadratic slope parameter alpha was determined to be -0.027 +/- 0.008(stat) +/- 0.005(syst). The result is consistent with previous measurements and further corroborates the importance of pion-pion final state interactions. (C) 2009 Elsevier B.V. All rights reserved.
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| 32. |
- Andrés, E., et al.
(författare)
-
Status of the AMANDA experiment
- 1999
-
Ingår i: Nuclear physics B, Proceedings supplements. - : Elsevier. - 0920-5632 .- 1873-3832. ; 70:1-3, s. 448-452
-
Tidskriftsartikel (refereegranskat)abstract
- The AMANDA high energy neutrino telescope has successfully been increased in size from four detector strings to ten detector strings during the 1996/1997 season. The first upward going muon-neutrino candidates have been reconstructed from the 1996 year's four-string data. Three new detector strings will be deployed during 1997/1998 to 2350 metres depth.
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| 33. |
- Kumar, R., et al.
(författare)
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ENHANCED 0(g.s.)(+) -> 2(1)(+) E2 TRANSITION STRENGTH IN Sn-112,Sn-114
- 2011
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Ingår i: Acta Physica Polonica B. - 0587-4254. ; 42:3-4, s. 813-816
-
Konferensbidrag (refereegranskat)abstract
- The poorly known B(E2; 0(+) -> 2(+)) values of Sn-112 and Sn-114 have been measured to high precision. Two Coulomb excitation experiments were performed to determine the reduced transition probabilities relative to Sn-116 in order to minimize the systematic errors. The obtained B(E2 up arrow) values of 0.242(8) e(2)b(2) for Sn-112 and 0.232(8) e(2)b(2) for Sn-114 confirm the tendency of large B(E2 up arrow) values for the lighter tin isotopes below the midshell Sn-116 that has been observed recently in various radioactive ion beam experiments.
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| 34. |
- Astell, A. J., et al.
(författare)
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Developing a pragmatic evaluation of ICTs for older adults with cognitive impairment at scale : the IN LIFE experience
- 2022
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Ingår i: Universal Access in the Information Society. - Heidelberg, Germany : Springer. - 1615-5289 .- 1615-5297. ; 21:1, s. 1-19
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Tidskriftsartikel (refereegranskat)abstract
- Implementing information and communications technology (ICT) at scale requires evaluation processes to capture the impacton users as well as the infrastructure into which it is being introduced. For older adults living with cognitive impairment, thisrequires evaluation that can accommodate diferent levels of cognitive impairment, alongside input from family and formalcaregivers, plus stakeholder organisations. The European Horizon 2020 project INdependent LIving support Functions forthe Elderly (IN LIFE) set out to integrate 17 technologies into a single digital platform for older people living with cognitive impairment plus their families, care providers and stakeholders. The IN LIFE evaluation took place across six nationalpilot sites to examine a number of variables including impact on the users, user acceptance of the individual services andthe overall platform, plus the economic case for the IN LIFE platform. The results confrmed the interest and need amongolder adults, family caregivers, formal caregivers and stakeholders, for information and communications technology (ICT).Relative to the baseline, quality of life improved and cognition stabilised; however, there was an overall reluctance to payfor the platform. The fndings provide insights into existing barriers and challenges for adoption of ICT for older peopleliving with cognitive impairment.
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| 35. |
- Astell, A. J., et al.
(författare)
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Developing a pragmatic evaluation of ICTs for older adults with cognitive impairment at scale: the IN LIFE experience
- 2021
-
Ingår i: Universal Access in the Information Society. - Heidelberg, Germany : Springer. - 1615-5289 .- 1615-5297.
-
Tidskriftsartikel (refereegranskat)abstract
- Implementing information and communications technology (ICT) at scale requires evaluation processes to capture the impact on users as well as the infrastructure into which it is being introduced. For older adults living with cognitive impairment, this requires evaluation that can accommodate different levels of cognitive impairment, alongside input from family and formal caregivers, plus stakeholder organisations. The European Horizon 2020 project INdependent LIving support Functions for the Elderly (IN LIFE) set out to integrate 17 technologies into a single digital platform for older people living with cognitive impairment plus their families, care providers and stakeholders. The IN LIFE evaluation took place across six national pilot sites to examine a number of variables including impact on the users, user acceptance of the individual services and the overall platform, plus the economic case for the IN LIFE platform. The results confirmed the interest and need among older adults, family caregivers, formal caregivers and stakeholders, for information and communications technology (ICT). Relative to the baseline, quality of life improved and cognition stabilised; however, there was an overall reluctance to pay for the platform. The findings provide insights into existing barriers and challenges for adoption of ICT for older people living with cognitive impairment.
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| 36. |
- Bashkanov, M., et al.
(författare)
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Two-pion production in proton-proton collisions
- 2004
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Ingår i: Hadron Spectroscopy, Tenth International Conference on Hadron Spectrscopy, Aschaffenburg, Germany 31 August - 6 September 2003. - 0735401977 ; , s. 241-244
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 37. |
- Bondar, A., et al.
(författare)
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The pp → ppπ0 reaction near the kinematical threshold
- 1995
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Ingår i: Physics Letters B. - : Elsevier. - 0370-2693 .- 1873-2445. ; 356:1, s. 8-12
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Tidskriftsartikel (refereegranskat)abstract
- The reaction pp → ppπ0 has been measured using electron-cooled protons incident on an internal gas-jet target at seven different incident beam energies, from 280.7 MeV (1 MeV above the reaction threshold) up to 310.2 MeV. The pions were measured by their decay photons. In the overlapping energy region, the measured total cross sections agree with those measured in a recent Indiana experiment. The angular distributions are consistent with a 3P0 → 1S0S0 transition in the full energy range studied. The kinematical distributions are well described when taking into account the final state and the Coulomb interactions.
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| 38. |
- Calén, H., et al.
(författare)
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Detector setup for a storage ring with an internal target
- 1996
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 379:1, s. 57-75
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Tidskriftsartikel (refereegranskat)abstract
- A detector setup for the cooler storage ring CELSIUS is described. The setup detects particles produced in interactions between the internal beam and a cluster-jet target. Particles emitted in the forward direction are measured by means of arrays of plastic scintillators and proportional counters. Particles, particularly photons, emitted more isotropically are measured by means of two calorimeters containing CsI(Na) crystals. The performance of the setup is given for neutral meson production in proton-proton and proton-deuteron interactions in the energy range 290-1360 MeV.
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| 39. |
- Calén, H, et al.
(författare)
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Detector setup for a storage ring with an internal target
- 1996
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Ingår i: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV. - 0168-9002. ; 379:1, s. 57-75
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Tidskriftsartikel (refereegranskat)abstract
- A detector setup for the cooler storage ring CELSIUS is described. The setup detects particles produced in interactions between the internal beam and a cluster-jet target. Particles emitted in the forward direction are measured by means of arrays of plast
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| 40. |
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| 41. |
- Clément, E., et al.
(författare)
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Low-energy Coulomb excitation of Sr 96,98 beams
- 2016
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 94:5, s. 054326-
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Tidskriftsartikel (refereegranskat)abstract
- The structure of neutron-rich Sr96,98 nuclei was investigated by low-energy safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility, CERN, with the MINIBALL spectrometer. A rich set of transitional and diagonal E2 matrix elements, including those for non-yrast structures, has been extracted from the differential Coulomb-excitation cross sections. The results support the scenario of a shape transition at N=60, giving rise to the coexistence of a highly deformed prolate and a spherical configuration in Sr98, and are compared to predictions from several theoretical calculations. The experimental data suggest a significant contribution of the triaxal degree of freedom in the ground state of both isotopes. In addition, experimental information on low-lying states in Rb98 has been obtained.
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| 42. |
- Clément, E, et al.
(författare)
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Spectroscopic Quadrupole Moments in ^{96,98}Sr: Evidence for Shape Coexistence in Neutron-Rich Strontium Isotopes at N=60.
- 2016
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Ingår i: Physical Review Letters. - 1079-7114. ; 116:2
-
Tidskriftsartikel (refereegranskat)abstract
- Neutron-rich ^{96,98}Sr isotopes have been investigated by safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility. Reduced transition probabilities and spectroscopic quadrupole moments have been extracted from the differential Coulomb excitation cross sections. These results allow, for the first time, the drawing of definite conclusions about the shape coexistence of highly deformed prolate and spherical configurations. In particular, a very small mixing between the coexisting states is observed, contrary to other mass regions where strong mixing is present. Experimental results have been compared to beyond-mean-field calculations using the Gogny D1S interaction in a five-dimensional collective Hamiltonian formalism, which reproduce the shape change at N=60.
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| 43. |
- Clement, H, et al.
(författare)
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Search for narrow NN-decoupled resonances in the pi NN-system - An overview
- 1996
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Ingår i: PROGRESS IN PARTICLE AND NUCLEAR PHYSICS. - : PERGAMON PRESS LTD. ; , s. 369-378
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Konferensbidrag (refereegranskat)abstract
- The status of the search for NN-decoupled resonances in the pi NN-system is reviewed. After a short survey on the history of dibaryon searches reactions suitable for detecting such resonances are discussed. Special emphasis is put on the pionic double cha
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| 44. |
- Hansen, Lea B.S., et al.
(författare)
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A low-gluten diet induces changes in the intestinal microbiome of healthy Danish adults
- 2018
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723 .- 2041-1723. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- © 2018, The Author(s). Adherence to a low-gluten diet has become increasingly common in parts of the general population. However, the effects of reducing gluten-rich food items including wheat, barley and rye cereals in healthy adults are unclear. Here, we undertook a randomised, controlled, cross-over trial involving 60 middle-aged Danish adults without known disorders with two 8-week interventions comparing a low-gluten diet (2 g gluten per day) and a high-gluten diet (18 g gluten per day), separated by a washout period of at least six weeks with habitual diet (12 g gluten per day). We find that, in comparison with a high-gluten diet, a low-gluten diet induces moderate changes in the intestinal microbiome, reduces fasting and postprandial hydrogen exhalation, and leads to improvements in self-reported bloating. These observations suggest that most of the effects of a low-gluten diet in non-coeliac adults may be driven by qualitative changes in dietary fibres.
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| 45. |
- Hurst, A. M., et al.
(författare)
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Measurement of the sign of the spectroscopic quadrupole moment for the 2(1)(+) state in Se-70: No evidence for oblate shape
- 2007
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Ingår i: Physical Review Letters. - 1079-7114. ; 98:7
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Tidskriftsartikel (refereegranskat)abstract
- Using a method whereby molecular and atomic ions are independently selected, an isobarically pure beam of Se-70 ions was postaccelerated to an energy of 206 MeV using REX-ISOLDE. Coulomb-excitation yields for states in the beam and target nuclei were deduced by recording deexcitation gamma rays in the highly segmented MINIBALL gamma-ray spectrometer in coincidence with scattered particles in a silicon detector. At these energies, the Coulomb-excitation yield for the first 2(+) state is expected to be strongly sensitive to the sign of the spectroscopic quadrupole moment through the nuclear reorientation effect. Experimental evidence is presented here for a prolate shape for the first 2(+) state in Se-70, reopening the question over whether there are, as reported earlier, deformed oblate shapes near to the ground state in the light selenium isotopes.
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| 46. |
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| 47. |
- Kröll, Th, et al.
(författare)
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Quadrupole Collectivity of neutron-rich nuclei around 132Sn
- 2008
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Ingår i: Frontiers in Nuclear Structure, Astrophysics, and Reactions, FINUSTAR 2007. - : AIP. - 9780735405325 ; 1012, s. 296-299
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Konferensbidrag (refereegranskat)abstract
- We report on the "safe" Coulomb excitation of neutron-rich Cd, Xe, and Ba isotopes in the vicinity of the doubly-magic nucleus 132Sn. The radioactive nuclei have been produced by ISOLDE at CERN and postaccelerated by the REX-ISOLDE facility. The γ-decay of excited states has been detected by the MINIBALL array. The presented preliminary results for the B(E2) values are consistent with expectations from phenomenological systematics and will be compared with theoretical calculations.
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| 48. |
- Munch Roager, Henrik, et al.
(författare)
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Whole grain-rich diet reduces body weight and systemic low-grade inflammation without inducing major changes of the gut microbiome: A randomised cross-over trial
- 2019
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Ingår i: Gut. - : BMJ. - 1468-3288 .- 0017-5749. ; 68:1, s. 83-93
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Tidskriftsartikel (refereegranskat)abstract
- Objective T o investigate whether a whole grain diet alters the gut microbiome and insulin sensitivity, as well as biomarkers of metabolic health and gut functionality. Design 60 Danish adults at risk of developing metabolic syndrome were included in a randomised cross-over trial with two 8-week dietary intervention periods comprising whole grain diet and refined grain diet, separated by a washout period of =6 weeks. The response to the interventions on the gut microbiome composition and insulin sensitivity as well on measures of glucose and lipid metabolism, gut functionality, inflammatory markers, anthropometry and urine metabolomics were assessed. Results 50 participants completed both periods with a whole grain intake of 179±50 g/day and 13±10 g/day in the whole grain and refined grain period, respectively. Compliance was confirmed by a difference in plasma alkylresorcinols (p<0.0001). Compared with refined grain, whole grain did not significantly alter glucose homeostasis and did not induce major changes in the faecal microbiome. Also, breath hydrogen levels, plasma short-chain fatty acids, intestinal integrity and intestinal transit time were not affected. The whole grain diet did, however, compared with the refined grain diet, decrease body weight (p<0.0001), serum inflammatory markers, interleukin (IL)-6 (p=0.009) and C-reactive protein (p=0.003). The reduction in body weight was consistent with a reduction in energy intake, and IL-6 reduction was associated with the amount of whole grain consumed, in particular with intake of rye. Conclusion C ompared with refined grain diet, whole grain diet did not alter insulin sensitivity and gut microbiome but reduced body weight and systemic lowgrade inflammation.
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| 49. |
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| 50. |
- Uvnäs-Moberg, Kerstin, et al.
(författare)
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Maternal plasma levels of oxytocin during breastfeeding-A systematic review
- 2020
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 15:8
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Oxytocin is a key hormone in breastfeeding. No recent review on plasma levels of oxytocin in response to breastfeeding is available. Materials and methods Systematic literature searches on breastfeeding induced oxytocin levels were conducted 2017 and 2019 in PubMed, Scopus, CINAHL, and PsycINFO. Data on oxytocin linked effects and effects of medical interventions were included if available. Results We found 29 articles that met the inclusion criteria. All studies had an exploratory design and included 601 women. Data were extracted from the articles and summarised in tables. Breastfeeding induced an immediate and short lasting (20 minutes) release of oxytocin. The release was pulsatile early postpartum (5 pulses/10 minutes) and coalesced into a more protracted rise as lactation proceeded. Oxytocin levels were higher in multiparous versus primiparous women. The number of oxytocin pulses during early breastfeeding was associated with greater milk yield and longer duration of lactation and was reduced by stress. Breastfeeding-induced oxytocin release was associated with elevated prolactin levels; lowered ACTH and cortisol (stress hormones) and somatostatin (a gastrointestinal hormone) levels; enhanced sociability; and reduced anxiety, suggesting that oxytocin induces physiological and psychological adaptations in the mother. Mechanical breast pumping, but not bottle-feeding was associated with oxytocin and prolactin release and decreased stress levels. Emergency caesarean section reduced oxytocin and prolactin release in response to breastfeeding and also maternal mental adaptations. Epidural analgesia reduced prolactin and mental adaptation, whereas infusions of synthetic oxytocin increased prolactin and mental adaptation. Oxytocin infusion also restored negative effects induced by caesarean section and epidural analgesia. Conclusions Oxytocin is released in response to breastfeeding to cause milk ejection, and to induce physiological changes to promote milk production and psychological adaptations to facilitate motherhood. Stress and medical interventions during birth may influence these effects and thereby adversely affect the initiation of breastfeeding.
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