| 1. |
- Schael, S., et al.
(författare)
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Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP
- 2013
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 532:4, s. 119-244
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Forskningsöversikt (refereegranskat)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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| 2. |
- Aleksic, J., et al.
(författare)
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DETECTION OF VERY HIGH ENERGY gamma-RAY EMISSION FROM THE PERSEUS CLUSTER HEAD-TAIL GALAXY IC 310 BY THE MAGIC TELESCOPES
- 2010
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Ingår i: The Astrophysical Journal Letters. - 2041-8205. ; 723:2, s. l207-L212
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Tidskriftsartikel (refereegranskat)abstract
- We report on the detection with the MAGIC telescopes of very high energy (VHE) gamma-rays from IC 310, a head-tail radio galaxy in the Perseus galaxy cluster, observed during the interval 2008 November to 2010 February. The Fermi satellite has also detected this galaxy. The source is detected by MAGIC at a high statistical significance of 7.6 sigma in 20.6 hr of stereo data. The observed spectral energy distribution is flat with a differential spectral index of -2.00 +/- 0.14. The mean flux above 300 GeV, between 2009 October and 2010 February, (3.1 +/- 0.5) x 10(-12) cm(-2) s(-1), corresponds to (2.5 +/- 0.4)% of Crab Nebula units. Only an upper limit, of 1.9% of Crab Nebula units above 300 GeV, was obtained with the 2008 data. This, together with strong hints (>3 sigma) of flares in the middle of 2009 October and November, implies that the emission is variable. The MAGIC results favor a scenario with the VHE emission originating from the inner jet close to the central engine. More complicated models than a simple one-zone synchrotron self-Compton (SSC) scenario, e. g., multi-zone SSC, external Compton, or hadronic, may be required to explain the very flat spectrum and its extension over more than three orders of magnitude in energy.
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| 3. |
- Grieser, M., et al.
(författare)
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Storage ring at HIE-ISOLDE Technical design report
- 2012
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Ingår i: The European Physical Journal Special Topics. - : Springer Science and Business Media LLC. - 1951-6355 .- 1951-6401. ; 207:1, s. 1-117
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Forskningsöversikt (refereegranskat)abstract
- We propose to install a storage ring at an ISOL-type radioactive beam facility for the first time. Specifically, we intend to setup the heavy-ion, low-energy ring TSR at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored secondary beams that is unique in the world. The envisaged physics programme is rich and varied, spanning from investigations of nuclear ground-state properties and reaction studies of astrophysical relevance, to investigations with highly-charged ions and pure isomeric beams. The TSR might also be employed for removal of isobaric contaminants from stored ion beams and for systematic studies within the neutrino beam programme. In addition to experiments performed using beams recirculating within the ring, cooled beams can also be extracted and exploited by external spectrometers for high-precision measurements. The existing TSR, which is presently in operation at the Max-Planck Institute for Nuclear Physics in Heidelberg, is well-suited and can be employed for this purpose. The physics cases as well as technical details of the existing ring facility and of the beam and infrastructure requirements at HIE-ISOLDE are discussed in the present technical design report.
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| 4. |
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| 5. |
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| 6. |
- Grieser, M., et al.
(författare)
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Storage ring at HIE-ISOLDE
- 2012
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Ingår i: European Physical Journal: Special Topics. - : Springer Science and Business Media LLC. - 1951-6401 .- 1951-6355. ; 207:1, s. 1-117
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Tidskriftsartikel (refereegranskat)abstract
- We propose to install a storage ring at an ISOL-type radioactive beam facility for the first time. Specifically, we intend to setup the heavy-ion, low-energy ring TSR at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored secondary beams that is unique in the world. The envisaged physics programme is rich and varied, spanning from investigations of nuclear ground-state properties and reaction studies of astrophysical relevance, to investigations with highly-charged ions and pure isomeric beams. The TSR might also be employed for removal of isobaric contaminants from stored ion beams and for systematic studies within the neutrino beam programme. In addition to experiments performed using beams recirculating within the ring, cooled beams can also be extracted and exploited by external spectrometers for high-precision measurements. The existing TSR, which is presently in operation at the Max-Planck Institute for Nuclear Physics in Heidelberg, is well-suited and can be employed for this purpose. The physics cases as well as technical details of the existing ring facility and of the beam and infrastructure requirements at HIE-ISOLDE are discussed in the present technical design report.
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| 7. |
- Litvinov, Yu.A., et al.
(författare)
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Nuclear physics experiments with ion storage rings
- 2013
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Ingår i: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - : Elsevier BV. - 0168-583X. ; 317:PART B, s. 603-616
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Tidskriftsartikel (refereegranskat)abstract
- In the last two decades a number of nuclear structure and astrophysics experiments were performed at heavy-ion storage rings employing unique experimental conditions offered by such machines. Furthermore, building on the experience gained at the two facilities presently in operation, several new storage ring projects were launched worldwide. This contribution is intended to provide a brief review of the fast growing field of nuclear structure and astrophysics research at storage rings.
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| 8. |
- Alves, C. F., et al.
(författare)
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Welcome from the IWSECO-WEA chairs
- 2014
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Ingår i: Proceedings - International Conference on Software Engineering. - New York, NY, USA : ACM. - 0270-5257.
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Konferensbidrag (refereegranskat)abstract
- The creation and adoption of a software ecosystem is becoming increasingly pervasive, leading to new research and management challenges. Several companies are platformizing successful products and opening these products up for outside innovation where customers expect to be actively involved in the shaping of the technology they use. This also leads to new opportunities and challenges regarding new business models, open innovation, collaborative development, strategic planning, and coordination of multiple platforms. IWSECO and WEA aim to further increase the body of knowledge in software ecosystems by providing a forum to exchange ideas and discuss the most recent innovations, trends and experiences in the field. It aims to build and shape the community of leading practitioners and research experts by providing a forum for the exchange of research results and industrial practice in software ecosystems. By co-locating both, IWSECO and WEA we aim at attracting and involving interested participants from the larger European software engineering community in an early stage of shaping software ecosystem research and community building. The co-located workshops will be a venue for practitioners and researchers to share experience and lessons learned; with a particular focus on architecture, as the ecosystem architecture can actually determine the success or failure of software ecosystems as a whole.
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| 9. |
- Castellsague, Xavier, et al.
(författare)
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Prospective seroepidemiologic study on the role of Human Papillomavirus and other infections in cervical carcinogenesis: Evidence from the EPIC cohort
- 2014
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 135:2, s. 440-452
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Tidskriftsartikel (refereegranskat)abstract
- To evaluate prospectively the association between serological markers of selected infections, including HPV, and risk of developing cervical cancer (CC) and precancer, we performed a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC) study that included 184 cases of invasive CC (ICC), 425 cases of cervical intraepithelial neoplasia (CIN) grade 3 or carcinoma in situ (CIS), and 1,218 matched control women. At enrollment participants completed lifestyle questionnaires and provided sera. Subjects were followed-up for a median of 9 years. Immunoassays were used to detect serum antibodies to Human Herpes Virus 2 (HHV-2), Chlamydia trachomatis (CT), Chlamydia pneumoniae, L1 proteins of mucosal and cutaneous HPV types, E6/E7 proteins of HPV16/18, as well as to four polyomaviruses. Adjusted odds ratios (OR) [and 95% confidence intervals (CI)] for CIN3/CIS and ICC risk were respectively: 1.6 (1.2-2.0) and 1.8 (1.1-2.7) for L1 seropositivity to any mucosal HPV type, 1.0 (0.4-2.4) and 7.4 (2.8-19.7) for E6 seropositivity to HPV16/18, 1.3 (0.9-1.9) and 2.3 (1.3-4.1) for CT seropositivity, and 1.4 (1.0-2.0) and 1.5 (0.9-2.6) for HHV-2 seropositivity. The highest OR for ICC was observed for HPV16 E6 seropositivity [OR=10.2 (3.3-31.1)]. Increasing number of sexually transmitted infections (STIs) was associated with increasing risk. Non-STIs were not associated with CC risk. In conclusion, this large prospective study confirms the important role of HPV and a possible contribution of CT and HHV-2 in cervical carcinogenesis. It further identifies HPV16 E6 seropositivity as the strongest marker to predict ICC well before disease development. What's New? Limited data are available from prospective studies concerning the role of past exposure to human papillomavirus (HPV) and other infections in cervical carcinogenesis. This study assessed associations between cervical cancer and pre-cancer and serological markers of exposure to mucosal and cutaneous HPVs, Chlamydia trachomatis (CT), Chlamydia pneumonia, human herpes virus-2 (HHV-2), and polyomaviruses using a nested case-control design within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Associations were found for mucosal HPVs, CT, and HHV-2. A greater number of sexually transmitted diseases further raised the risk of cervical cancer.
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| 10. |
- Daeichin, Verya, 1984, et al.
(författare)
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Effect of self-demodulation on the subharmonic response of contrast agent microbubbles
- 2012
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Ingår i: Physics in Medicine and Biology. - : IOP Publishing. - 0031-9155 .- 1361-6560. ; 57:12, s. 3675-3691
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Tidskriftsartikel (refereegranskat)abstract
- Subharmonic (SH) emission from the ultrasound contrast agent (UCA) is of interest since it is produced only by the UCA and not by tissue, opposite to harmonic imaging modes where both tissue and microbubble show harmonics. In this work, the use of the self-demodulation (S-D) signal as a means of microbubble excitation at the SH frequency to enhance the SH emission of UCA is studied. The S-D wave is a low-frequency signal produced by the weak nonlinear propagation of an ultrasound wave. It is proportional to the second time derivative of the squared envelope of the transmitted signal. A diluted population of BR14 UCA (Bracco Research SA, Geneva, Switzerland) was insonified by a 10 MHz transducer focused at 76 mm firing bursts with different envelopes, durations and peak pressure amplitudes. The center frequency of the S-D signal changes from low frequencies (around 0.5 MHz) toward the transmitted frequency (10 MHz) by modifying the envelope function from Gaussian to rectangular. For 6 and 20 transmitted cycles, the SH response is enhanced up to 25 and 22 dB, respectively, when using a rectangular envelope instead of a Gaussian one. The experimental results are confirmed by the numerical simulation. The effects of the excitation duration and pressure amplitude are also studied. This study shows that a suitable design of the envelope of the transmit excitation to generate a S-D signal at the SH frequency can enhance the SH emission of UCA, and the SH imaging is feasible at high frequencies with a shorter transmit burst (six-cycle) and low acoustic pressure (similar to 100 KPa).
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