| 1. |
- Adrian-Martinez, S., et al.
(författare)
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A first search for coincident gravitational waves and high energy neutrinos using LIGO, Virgo and ANTARES data from 2007
- 2013
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Ingår i: Journal of Cosmology and Astroparticle Physics. - : IOP Publishing. - 1475-7516. ; :6
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Tidskriftsartikel (refereegranskat)abstract
- We present the results of the first search for gravitational wave bursts associated with high energy neutrinos. Together, these messengers could reveal new, hidden sources that are not observed by conventional photon astronomy, particularly at high energy. Our search uses neutrinos detected by the underwater neutrino telescope ANTARES in its 5 line configuration during the period January - September 2007, which coincided with the fifth and first science runs of LIGO and Virgo, respectively. The LIGO-Virgo data were analysed for candidate gravitational-wave signals coincident in time and direction with the neutrino events. No significant coincident events were observed. We place limits on the density of joint high energy neutrino - gravitational wave emission events in the local universe, and compare them with densities of merger and core-collapse events.
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| 2. |
- Ageron, M., et al.
(författare)
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ANTARES : The first undersea neutrino telescope
- 2011
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 656:1, s. 11-38
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Tidskriftsartikel (refereegranskat)abstract
- The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given. (C) 2011 Elsevier B.V. All rights reserved.
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| 3. |
- Feroci, M., et al.
(författare)
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The large observatory for x-ray timing
- 2014
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 9780819496126
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Konferensbidrag (refereegranskat)abstract
- The Large Observatory For x-ray Timing (LOFT) was studied within ESA M3 Cosmic Vision framework and participated in the final downselection for a launch slot in 2022-2024. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument, LOFT will study the behaviour of matter under extreme conditions, such as the strong gravitational field in the innermost regions of accretion flows close to black holes and neutron stars, and the supranuclear densities in the interior of neutron stars. The science payload is based on a Large Area Detector (LAD, 10 m2 effective area, 2-30 keV, 240 eV spectral resolution, 1° collimated field of view) and a Wide Field Monitor (WFM, 2-50 keV, 4 steradian field of view, 1 arcmin source location accuracy, 300 eV spectral resolution). The WFM is equipped with an on-board system for bright events (e.g. GRB) localization. The trigger time and position of these events are broadcast to the ground within 30 s from discovery. In this paper we present the status of the mission at the end of its Phase A study.
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| 4. |
- Feroci, M., et al.
(författare)
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LOFT - The large observatory for x-ray timing
- 2012
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE - International Society for Optical Engineering. - 9780819491442 ; , s. 84432D-
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Konferensbidrag (refereegranskat)abstract
- The LOFT mission concept is one of four candidates selected by ESA for the M3 launch opportunity as Medium Size missions of the Cosmic Vision programme. The launch window is currently planned for between 2022 and 2024. LOFT is designed to exploit the diagnostics of rapid X-ray flux and spectral variability that directly probe the motion of matter down to distances very close to black holes and neutron stars, as well as the physical state of ultradense matter. These primary science goals will be addressed by a payload composed of a Large Area Detector (LAD) and a Wide Field Monitor (WFM). The LAD is a collimated (<1 degree field of view) experiment operating in the energy range 2-50 keV, with a 10 m2 peak effective area and an energy resolution of 260 eV at 6 keV. The WFM will operate in the same energy range as the LAD, enabling simultaneous monitoring of a few-steradian wide field of view, with an angular resolution of <5 arcmin. The LAD and WFM experiments will allow us to investigate variability from submillisecond QPO's to yearlong transient outbursts. In this paper we report the current status of the project.
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| 5. |
- Thide, Bo, et al.
(författare)
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Angular Momentum Radio
- 2014
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Ingår i: Complex Light and Optical Forces VIII. - : SPIE. - 9780819499127 ; , s. 89990B-
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Konferensbidrag (refereegranskat)abstract
- Wireless communication amounts to encoding information onto physical observables carried by electromagnetic (EM) fields, radiating them into surrounding space, and detecting them remotely by an appropriate sensor connected to an information-decoding receiver. Each observable is second order in the fields and fulfills a conservation law. In present-day radio only the EM linear momentum observable is fully exploited. A fundamental physical limitation of this observable, which represents the translational degrees of freedom of the charges (typically an oscillating current along a linear antenna) and the fields, is that it is single-mode. This means that a linear-momentum radio communication link comprising one transmitting and one receiving antenna, known as a single-input-single-output (SISO) link, can provide only one transmission channel per frequency (and polarization). In contrast, angular momentum, which represents the rotational degrees of freedom, is multi-mode, allowing an angular-momentum SISO link to accommodate an arbitrary number of independent transmission channels on one and the same frequency (and polarization). We describe the physical properties of EM angular momentum and how they can be exploited, discuss real-world experiments, and outline how the capacity of angular momentum links may be further enhanced by employing multi-port techniques, i.e., the angular momentum counterpart of linear-momentum multiple-input-multiple-output (MIMO).
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| 6. |
- Mari, E., et al.
(författare)
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Sub-Rayleigh optical vortex coronagraphy
- 2012
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Ingår i: Optics Express. - 1094-4087. ; 20:3, s. 2445-2451
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Tidskriftsartikel (refereegranskat)abstract
- We introduce a new optical vortex coronagraph(OVC) method to determine the angular distance between two sources when the separation is sub-Rayleigh. We have found a direct relationship between the position of the minima and the source angular separation. A priori knowledge about the location of the two sources is not required. The superresolution capabilities of an OVC, equipped with an l = 2 N-step spiral phase plate in its optical path, were investigated numerically. The results of these investigations show that a fraction of the light, increasing with N, from the secondary source can be detected with a sub-Rayleigh resolution of at least 0.1 lambda/D.
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| 7. |
- Tamburini, F., et al.
(författare)
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Reply to Comment on 'Encoding many channels on the same frequency through radio vorticity : first experimental test'
- 2012
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Ingår i: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 14, s. 118002-
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Our recent paper (Tamburini et al 2012 New J. Phys. 14 033001), which presented results from outdoor experiments that demonstrate that it is physically feasible to simultaneously transmit different states of the newly recognized electromagnetic (EM) quantity orbital angular momentum (OAM) at radio frequencies into the far zone and to identify these states there, has led to a comment (Tamagnone et al 2012 New J. Phys. 14 118001). These authors discuss whether our investigations can be regarded as a particular implementation of the multiple-input-multiple-output (MIMO) technique. Clearly, our experimental confirmation of a theoretical prediction, first made almost a century ago (Abraham 1914 Phys. Z. XV 914-8), that the total EM angular momentum (a pseudovector of dimension length x mass x velocity) can propagate over huge distances, is essentially different from-and conceptually incompatible with-the fact that there exist engineering techniques that can enhance the spectral capacity of EM linear momentum (an ordinary vector of dimension mass x velocity). Our OAM experiments (Tamburini et al 2012 New J. Phys. 14 033001; Tamburini et al 2011 Appl. Phys. Lett. 99 204102-3) confirm the availability of a new physical layer for real-world radio communications based on EM rotational degrees of freedom. The next step is to develop new protocols and techniques for high spectral density on this new physical layer. This includes MIMO-like and other, more efficient, techniques.
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| 8. |
- Burd, Adrian B., et al.
(författare)
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Assessing the Apparent Imbalance Between Geochemical and Biochemical Indicators of Meso- and Bathypelagic Biological Activity: What the @$#! is wrong with present calculations of carbon budgets?
- 2010
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Ingår i: Deep-sea research. Part II, Topical studies in oceanography. - : Elsevier BV. - 0967-0645 .- 1879-0100. ; 57:16, s. 1557-1571
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Tidskriftsartikel (refereegranskat)abstract
- Metabolic activity in the water column below the euphotic zone is ultimately fuelled by the vertical flux of organic material from the surface. Over time, the deep ocean is presumably at steady state, with sources and sinks balanced. But recently compiled global budgets and intensive local field studies suggest that estimates of metabolic activity in the dark ocean exceed the influx of organic substrates. This imbalance indicates either the existence of unaccounted sources of organic carbon or that metabolic activity in the dark ocean is being over-estimated. Budgets of organic carbon flux and metabolic activity in the dark ocean have uncertainties associated with environmental variability, measurement capabilities, conversion parameters, and processes that are not well sampled. We present these issues and quantify associated uncertainties where possible, using a Monte Carlo analysis of a published data set to determine the probability that the imbalance can be explained purely by uncertainties in measurements and conversion factors. A sensitivity analysis demonstrates that the bacterial growth efficiencies and assumed cell carbon contents have the greatest effects on the magnitude of the carbon imbalance. Two poorly quantified sources, lateral advection of particles and a population of slowly settling particles, are discussed as providing a means of closing regional carbon budgets. Finally, we make recommendations concerning future research directions to reduce important uncertainties and allow a better determination of the magnitude and causes of the unbalanced carbon budgets. (C) 2010 Elsevier Ltd. All rights reserved.
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| 9. |
- Ferrari, S., et al.
(författare)
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Nonmetastatic Ewing family tumors: high-dose chemotherapy with stem cell rescue in poor responder patients. Results of the Italian Sarcoma Group/Scandinavian Sarcoma Group III protocol
- 2011
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Ingår i: Annals of Oncology. - : Elsevier BV. - 1569-8041 .- 0923-7534. ; 22:5, s. 1221-1227
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Tidskriftsartikel (refereegranskat)abstract
- Background: High-dose chemotherapy (HDT) was added to conventional chemotherapy in Ewing sarcoma family tumor (EFT) patients, poor responders (PRs) to induction chemotherapy in order to improve their survival. Patients and methods: Patients aged <= 40 years with nonmetastatic Ewing sarcoma (ES) received vincristine (V), doxorubicin (A), cyclofosfamide (C), actinomycin (Ac), ifosfamide (I) and etoposide (E) (VACAc-IE regimen) as induction chemotherapy. As maintenance treatment, good responders (GR) received nine cycles of VACAc-IE regimen. PRs received three cycles of VAC-IE, mobilizing cycle with CE and HDT with Busulfan and Melphalan with stem cell support. Results: Three hundred patients [median age 15 years (3-40 years)] entered the study. One patient refused local treatment, 242 (81%) underwent surgery [with radiotherapy (RT) in 80] and 57 (19%) RT alone. No toxic deaths were recorded. Overall GR were 146 (49%). Twenty-eight PR did not receive HDT. At a median follow-up of 64 months (21-116 months), 5-year overall and event-free survival (EFS) were 75% and 69%, respectively. Five-year EFS was 75% for GR, 72% for PR treated with HDT and 33% for PR who did not receive HDT. Conclusions: High-dose therapy added to the VACA-IE regimen in PR patients is feasible and effective. Selected groups of patients with ES can benefit from HDT.
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| 10. |
- Luksch, R., et al.
(författare)
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Primary metastatic Ewing's family tumors: results of the Italian Sarcoma Group and Scandinavian Sarcoma Group ISG/SSG IV Study including myeloablative chemotherapy and total-lung irradiation
- 2012
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Ingår i: Annals of Oncology. - : Elsevier BV. - 1569-8041 .- 0923-7534. ; 23:11, s. 2970-2976
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Tidskriftsartikel (refereegranskat)abstract
- The Italian Sarcoma Group and the Scandinavian Sarcoma Group designed a joint study to improve the prognosis for patients with Ewing's family tumors and synchronous metastatic disease limited to the lungs, or the pleura, or a single bone. The study was opened in 1999 and closed to the enrollment in 2008. The program consisted of intensive five-drug combination chemotherapy, surgery and/or radiotherapy as local treatment, and consolidation treatment with high-dose busulfan/melphalan plus autologous stem cell rescue and total-lung irradiation. During the study period, 102 consecutive patients were enrolled. The median follow-up was 62 months (range 24-124). The 5-year event-free survival probability was 0.43 [standard deviation (SD) = 0.05] and the 5-year overall survival probability was 0.52 (SD = 0.052). Unfavorable prognostic factors emerging on multivariate analysis were a poor histological/radiological response at the site of the primary tumor [relative risk (RR) = 3.4], and incomplete radiological remission of lung metastases after primary chemotherapy (RR = 2.6). One toxic death and one secondary leukemia were recorded. This intensive approach is feasible and long-term survival is achievable in similar to 50% of patients. New treatment approaches are warranted for patients responding poorly to primary chemotherapy.
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| 11. |
- Tamburini, F., et al.
(författare)
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Photon orbital angular momentum and mass in a plasma vortex
- 2010
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Ingår i: Europhysics letters. - : IOP Publishing. - 0295-5075 .- 1286-4854. ; 90:4, s. 45001-
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Tidskriftsartikel (refereegranskat)abstract
- We analyse the Anderson-Higgs mechanism of photon mass acquisition in a plasma and study the contribution to the mass from the orbital angular momentum acquired by a beam of photons when it crosses a spatially structured charge distribution. To this end we apply Proca-Maxwell equations in a static plasma with a particular spatial distribution of free charges, notably a plasma vortex, that is able to impose orbital angular momentum (OAM) onto light. In addition to the mass acquisition of the conventional Anderson-Higgs mechanism, we find that the photon acquires an additional mass from the OAM and that this mass reduces the Proca photon mass.
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| 12. |
- Tamburini, F., et al.
(författare)
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Storming Majorana's Tower with OAM states of light in a plasma
- 2011
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Ingår i: Europhysics letters. - : IOP Publishing. - 0295-5075 .- 1286-4854. ; 96:6, s. 64005-
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Tidskriftsartikel (refereegranskat)abstract
- We extend the relationship between mass and spin angular momentum, described by the bosonic spectrum of positive definite mass particles of the Majorana solution to the Dirac equation, to photons that acquire an effective Proca mass through the Anderson-Higgs mechanism (Anderson P. W., Phys. Rev., 130 (1963) 439) when they propagate in a plasma. In an earlier paper (TAMBURINI F. et al., EPL, 90 (2010) 45001) we showed that if the plasma is structured, it can impart orbital angular momentum (OAM) to the photons that reduces the total Proca photon mass. Here we show, through a generalisation of Majorana's solution, that photons with OAM in a plasma cannot assume negative squared mass states. This means that there exist interesting analogies with Quantum Gravity or General Relativity models involving a modified action of the Lorentz group.
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