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Author |
Vagnozzi, S.; Di Valentino, E.; Gariazzo, S.; Melchiorri, A.; Mena, O.; Silk, J. |
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Title |
The galaxy power spectrum take on spatial curvature and cosmic concordance |
Type |
Journal Article |
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Year |
2021 |
Publication |
Physics of the Dark Universe |
Abbreviated Journal |
Phys. Dark Universe |
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Volume |
33 |
Issue |
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Pages |
100851 - 17pp |
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Keywords |
Cosmological parameters; Spatial curvature; Cosmological tensions |
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Abstract |
The concordance of the ACDM cosmological model in light of current observations has been the subject of an intense debate in recent months. The 2018 Planck Cosmic Microwave Background (CMB) temperature anisotropy power spectrum measurements appear at face value to favour a spatially closed Universe with curvature parameter Omega(K) < 0. This preference disappears if Baryon Acoustic Oscillation (BAO) measurements are combined with Planck data to break the geometrical degeneracy, although the reliability of this combination has been questioned due to the strong tension present between the two datasets when assuming a curved Universe. Here, we approach this issue from yet another point of view, using measurements of the full-shape (FS) galaxy power spectrum, P(k), from the Baryon Oscillation Spectroscopic Survey DR12 CMASS sample. By combining Planck data with FS measurements, we break the geometrical degeneracy and find Omega(K) = 0.0023 +/- 0.0028. This constrains the Universe to be spatially flat to sub-percent precision, in excellent agreement with results obtained using BAO measurements. However, as with BAO, the overall increase in the best-fit chi(2) suggests a similar level of tension between Planck and P(k) under the assumption of a curved Universe. While the debate on spatial curvature and the concordance between cosmological datasets remains open, our results provide new perspectives on the issue, highlighting the crucial role of FS measurements in the era of precision cosmology. |
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Address |
[Vagnozzi, Sunny] Univ Cambridge, Kavli Inst Cosmol, Cambridge CB3 0HA, England, Email: sunny.vagnozzi@ast.cam.ac.uk; |
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Elsevier |
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English |
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Conference |
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Notes |
WOS:000704383100022 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4984 |
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Permanent link to this record |
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Author |
Vagnozzi, S.; Visinelli, L.; Mena, O.; Mota, D.F. |
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Title |
Do we have any hope of detecting scattering between dark energy and baryons through cosmology? |
Type |
Journal Article |
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Year |
2020 |
Publication |
Monthly Notices of the Royal Astronomical Society |
Abbreviated Journal |
Mon. Not. Roy. Astron. Soc. |
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Volume |
493 |
Issue |
1 |
Pages |
1139-1152 |
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Keywords |
cosmic background radiation; cosmological parameters; cosm logy: observations; dark energy; large-scale structure of Universe |
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Abstract |
We consider the possibility that dark energy and baryons might scatter off each other. The type of interaction we consider leads to a pure momentum exchange, and does not affect the background evolution of the expansion history. We parametrize this interaction in an effective way at the level of Boltzmann equations. We compute the effect of dark energy-baryon scattering on cosmological observables, focusing on the cosmic microwave background (CMB) temperature anisotropy power spectrum and the matter power spectrum. Surprisingly, we find that even huge dark energy-baryon cross-sections sigma(xb) similar to O(b), which are generically excluded by non-cosmological probes such as collider searches or precision gravity tests, only leave an insignificant imprint on the observables considered. In the case of the CMB temperature power spectrum, the only imprint consists in a sub-per cent enhancement or depletion of power (depending whether or not the dark energy equation of state lies above or below -1) at very low multipoles, which is thus swamped by cosmic variance. These effects are explained in terms of differences in how gravitational potentials decay in the presence of a dark energy-baryon scattering, which ultimately lead to an increase or decrease in the late-time integrated Sachs-Wolfe power. Even smaller related effects are imprinted on the matter power spectrum. The imprints on the CMB are not expected to be degenerate with the effects due to altering the dark energy sound speed. We conclude that, while strongly appealing, the prospects for a direct detection of dark energy through cosmology do not seem feasible when considering realistic dark energy-baryon cross-sections. As a caveat, our results hold to linear order in perturbation theory. |
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Address |
[Vagnozzi, Sunny] Univ Cambridge, Kat Inst Cosmol, Madingley Rd, Cambridge CB3 0HA, England, Email: sunny.vagnozzi@ast.cam.ac.uk |
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Oxford Univ Press |
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English |
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ISSN |
0035-8711 |
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Expedition |
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Conference |
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Notes |
WOS:000518156100081 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4320 |
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Permanent link to this record |
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Author |
n_TOF Collaboration (Sosnin, N.V. et al.); Babiano-Suarez, V.; Caballero, L.; Domingo-Pardo, C.; Ladarescu, I.; Tain, J.L. |
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Title |
Measurement of the 77Se(n,gamma) cross section up to 200 keV at the n_TOF facility at CERN |
Type |
Journal Article |
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Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
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Volume |
107 |
Issue |
6 |
Pages |
065805 - 9pp |
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Keywords |
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Abstract |
The 77Se(n,gamma) reaction is of importance for 77Se abundance during the slow neutron capture process in massive stars. We have performed a new measurement of the 77Se radiative neutron capture cross section at the Neutron Time-of-Flight facility at CERN. Resonance capture kernels were derived up to 51 keV and cross sections up to 200 keV. Maxwellian-averaged cross sections were calculated for stellar temperatures between kT = 5 keV and kT = 100 keV, with uncertainties between 4.2% and 5.7%. Our results lead to substantial decreases of 14% and 19% in 77Se abundances produced through the slow neutron capture process in selected stellar models of 15M0 and 2M0, respectively, compared to using previous recommendation of the cross section. |
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Address |
[V. Sosnin, N.; Lederer-Woods, C.; Garg, R.; Dietz, M.; Murphy, A. St. J.; Lonsdale, S.; Woods, P. J.] Univ Edinburgh, Sch Phys & Astron, Edinburgh, Scotland, Email: nsosnin@ed.ac.uk |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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English |
Summary Language |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9985 |
ISBN |
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Expedition |
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Conference |
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Notes |
WOS:001023903800002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5599 |
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Permanent link to this record |
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Author |
Utrilla Gines, E.; Mena, O.; Witte, S.J. |
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Title |
Revisiting constraints on WIMPs around primordial black holes |
Type |
Journal Article |
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Year |
2022 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
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Volume |
106 |
Issue |
6 |
Pages |
063538 - 14pp |
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Keywords |
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Abstract |
While primordial black holes (PBHs) with masses MPBH greater than or similar to 10-11 Mo cannot comprise the entirety of dark matter, the existence of even a small population of these objects can have profound astrophysical consequences. A subdominant population of PBHs will efficiently accrete dark matter particles before matter-radiation equality, giving rise to high-density dark matter spikes. We consider here the scenario in which dark matter is comprised primarily of weakly interacting massive particles (WIMPs) with a small subdominant contribution coming from PBHs, and revisit the constraints on the annihilation of WIMPs in these spikes using observations of the isotropic gamma-ray background (IGRB) and the cosmic microwave background (CMB), for a range of WIMP masses, annihilation channels, cross sections, and PBH mass functions. We find that the constraints derived using the IGRB have been significantly overestimated (in some cases by many orders of magnitude), and that limits obtained using observations of the CMB are typically stronger than, or comparable to, those coming from the IGRB. Importantly, we show that similar to OoMo thorn PBHs can still contribute significantly to the dark matter density for sufficiently low WIMP masses and p-wave annihilation cross sections. |
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Address |
[Utrilla Gines, Estanis; Mena, Olga] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Parc Cient UV,C Catedrat Jose Beltran 2, E-46980 Paterna, Spain |
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Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
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English |
Summary Language |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2470-0010 |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000866519600007 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5390 |
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Permanent link to this record |
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Author |
ANTARES Collaboration (Albert, A. et al); Barrios-Marti, J.; Coleiro, A.; Colomer, M.; Hernandez-Rey, J.J.; Illuminati, G.; Lotze, M.; Zornoza, J.D.; Zuñiga, J. |
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Title |
The search for high-energy neutrinos coincident with fast radio bursts with the ANTARES neutrino telescope |
Type |
Journal Article |
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Year |
2019 |
Publication |
Monthly Notices of the Royal Astronomical Society |
Abbreviated Journal |
Mon. Not. Roy. Astron. Soc. |
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Volume |
482 |
Issue |
1 |
Pages |
184-193 |
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Keywords |
acceleration of particles; neutrinos; astroparticle physics; radio continuum: transients; methods: data analysis |
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Abstract |
In the past decade, a new class of bright transient radio sources with millisecond duration has been discovered. The origin of these so-called fast radio bursts (FRBs) is still a mystery, despite the growing observational efforts made by various multiwavelength and multimessenger facilities. To date, many models have been proposed to explain FRBs, but neither the progenitors nor the radiative and the particle acceleration processes at work have been clearly identified. In this paper, we assess whether hadronic processes may occur in the vicinity of the FRB source. If they do, FRBs may contribute to the high-energy cosmic-ray and neutrino fluxes. A search for these hadronic signatures was carried out using the ANTARES neutrino telescope. The analysis consists in looking for high-energy neutrinos, in the TeV-PeV regime, that are spatially and temporally coincident with the detected FRBs. Most of the FRBs discovered in the period 2013-2017 were in the field of view of the ANTARES detector, which is sensitive mostly to events originating from the Southern hemisphere. From this period, 12 FRBs were selected and no coincident neutrino candidate was observed. Upper limits on the per-burst neutrino fluence were derived using a power-law spectrum, dN/DE nu proportional to E-nu(-gamma), for the incoming neutrino flux, assuming spectral indexes gamma = 1.0, 2.0, 2.5. Finally, the neutrino energy was constrained by computing the total energy radiated in neutrinos, assuming different distances for the FRBs. Constraints on the neutrino fluence and on the energy released were derived from the associated null results. |
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Address |
[Turpin, D.] Chinese Acad Sci, Natl Astron Observ, Key Lab Space Astron & Technol, Beijing 100101, Peoples R China, Email: dornic@cppm.in2p3.fr; |
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Publisher |
Oxford Univ Press |
Place of Publication |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0035-8711 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000454575300014 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3860 |
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Permanent link to this record |
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Author |
NEXT Collaboration (Trindade, A.M.F. et al); Alvarez, V.; Benlloch-Rodriguez, J.M.; Botas, A.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Ferrario, P.; Gomez-Cadenas, J.J.; Laing, A.; Liubarsky, I; Lopez-March, N.; Martinez, A.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Perez, J.; Querol, M.; Renner, J.; Rodriguez, J.; Simon, A.; Sorel, M.; Torrent, J.; Yahlali, N. |
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Title |
Study of the loss of xenon scintillation in xenon-trimethylamine mixtures |
Type |
Journal Article |
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Year |
2018 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
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Volume |
905 |
Issue |
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Pages |
22-28 |
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Keywords |
Gaseous radiation detectors; Noble gas mixtures; Molecular additives; VUV absorption |
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Abstract |
This work investigates the capability of TMA ((CH3)(3)N) molecules to shift the wavelength of Xe VUV emission (160-188 nm) to a longer, more manageable, wavelength (260-350 nm). Light emitted from a Xe lamp was passed through a gas chamber filled with Xe-TMA mixtures at 800 Torr and detected with a photomultiplier tube. Using bandpass filters in the proper transmission ranges, no reemitted light was observed experimentally. Considering the detection limit of the experimental system, if reemission by TMA molecules occurs, it is below 0.3% of the scintillation absorbed in the 160-188 nm range. An absorption coefficient value for xenon VUV light by TMA of 0.43 +/- 0.03 cm(-1) Torr(-1) was also obtained. These results can be especially important for experiments considering TMA as a molecular additive to Xe in large volume optical time projection chambers. |
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Address |
[Trindade, A. M. F.; Escada, J.; Cortez, A. F., V; Borges, F. I. G. M.; Santos, F. P.; Conde, C. A. N.] LIP Lab Instrumentacao & Fis Expt Particulas, Coimbra, Portugal, Email: Kalexandre.trindade@coimbra.lip.pt |
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Publisher |
Elsevier Science Bv |
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English |
Summary Language |
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Edition |
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ISSN |
0168-9002 |
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Conference |
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Notes |
WOS:000444425700003 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3730 |
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Permanent link to this record |
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Author |
Toubiana, A.; Sberna, L.; Caputo, A.; Cusin, G.; Marsat, S.; Jani, K.; Babak, S.; Barausse, E.; Caprini, C.; Pani, P.; Sesana, A.; Tamanini, N. |
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Title |
Detectable Environmental Effects in GW190521-like Black-Hole Binaries with LISA |
Type |
Journal Article |
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Year |
2021 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
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Volume |
126 |
Issue |
10 |
Pages |
101105 - 6pp |
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Keywords |
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Abstract |
GW190521 is the compact binary with the largest masses observed to date, with at least one black hole in the pair-instability gap. This event has also been claimed to be associated with an optical flare observed by the Zwicky Transient Facility in an active galactic nucleus (AGN), possibly due to the postmerger motion of the merger remnant in the AGN gaseous disk. The Laser Interferometer Space Antenna (LISA) may detect up to ten such gas-rich black-hole binaries months to years before their detection by Laser Interferometer Gravitational Wave Observatory or Virgo-like interferometers, localizing them in the sky within approximate to 1 degrees(2). LISA will also measure directly deviations from purely vacuum and stationary waveforms arising from gas accretion, dynamical friction, and orbital motion around the AGN's massive black hole (acceleration, strong lensing, and Doppler modulation). LISA will therefore be crucial to enable us to point electromagnetic telescopes ahead of time toward this novel class of gas-rich sources, to gain direct insight on their physics, and to disentangle environmental effects from corrections to general relativity that may also appear in the waveforms at low frequencies. |
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Address |
[Toubiana, Alexandre; Marsat, Sylvain; Babak, Stanislav; Caprini, Chiara] Univ Paris, CNRS, AstroParticule & Cosmol, APC, F-75013 Paris, France |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9007 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000652824700005 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4846 |
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Permanent link to this record |
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Author |
Tortajada, S.; Albiol, F.; Caballero, L.; Albiol, A.; Leganes-Nieto, J.L. |
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Title |
A portable geometry-independent tomographic system for gamma-ray, a next generation of nuclear waste characterization |
Type |
Journal Article |
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Year |
2023 |
Publication |
Scientific Reports |
Abbreviated Journal |
Sci Rep |
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Volume |
13 |
Issue |
1 |
Pages |
12284 - 10pp |
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Keywords |
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Abstract |
One of the main activities of the nuclear industry is the characterisation of radioactive waste based on the detection of gamma radiation. Large volumes of radioactive waste are classified according to their average activity, but often the radioactivity exceeds the maximum allowed by regulators in specific parts of the bulk. In addition, the detection of the radiation is currently based on static detection systems where the geometry of the bulk is fixed and well known. Furthermore, these systems are not portable and depend on the transport of waste to the places where the detection systems are located. However, there are situations where the geometry varies and where moving waste is complex. This is especially true in compromised situations.We present a new model for nuclear waste management based on a portable and geometry-independent tomographic system for three-dimensional image reconstruction for gamma radiation detection. The system relies on a combination of a gamma radiation camera and a visible camera that allows to visualise radioactivity using augmented reality and artificial computer vision techniques. This novel tomographic system has the potential to be a disruptive innovation in the nuclear industry for nuclear waste management. |
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Address |
[Tortajada, Salvador; Albiol, Francisco; Caballero, Luis] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46980 Paterna Valencia, Spain, Email: s.tortajada@ific.uv.es |
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Publisher |
Nature Portfolio |
Place of Publication |
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Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
2045-2322 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001041587900052 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
no |
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Call Number |
IFIC @ pastor @ |
Serial |
5612 |
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Permanent link to this record |
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Author |
Torres-Sanchez, P.; Steiger, H.T.J.; Mastinu, P.; Wyss, J.L.; Kayser, L.; Silvestrin, L.; Musacchio-Gonzalez, E.; Stock, M.R.; Dörflinger, D.; Fahrendholz, U.; Prete, G.; Carletto, O.; Oberauer, L.; Porras, I. |
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Title |
Fast neutron production at the LNL Tandem from the 7Li(14N,xn)X reaction |
Type |
Journal Article |
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Year |
2024 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
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Volume |
84 |
Issue |
4 |
Pages |
372 - 11pp |
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Keywords |
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Abstract |
Fast neutron beams (E-n>1 MeV) are of relevance for many scientific and industrial applications. This paper explores fast neutron production using a TANDEM accelerator at the Legnaro National Laboratories, via an energetic ion beam (90 MeV N-14) onto a lithium target. The high energy models for nuclear collision of FLUKA foresee large neutron yields for reactions of this kind. The experiment aimed at validating the expected neutron yields from FLUKA simulations, using two separate and independent set-ups: one based on the multi-foil activation technique, and the other on the time of flight technique, by using liquid scintillator detectors. The results of the experiment show clear agreement of the measured spectra with the FLUKA simulations, both in the shape and the magnitude of the neutron flux at the mea-sured positions. The neutron spectrum is centered around the 8 MeV range with mild tails, and a maximum neutron energy spanning up to 50 MeV. These advantageous results provide a starting point in the development of fast neutron beams based on high energy ion beams from medium-sized accelerator facilities |
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Address |
[Torres-Sanchez, Pablo] Univ Valencia, Inst Fis Corpuscular, CSIC, Valencia, Spain, Email: pablotorres@ific.uv.es; |
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Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-6044 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001198645600001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
6107 |
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Permanent link to this record |
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Author |
n_TOF Collaboration (Torres-Sanchez, P. et al); Babiano-Suarez, V.; Caballero, L.; Domingo-Pardo, C.; Ladarescu, I.; Tain, J.L. |
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Title |
Measurement of the 14N(n, p) 14C cross section at the CERN n_TOF facility from subthermal energy to 800 keV |
Type |
Journal Article |
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Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
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Volume |
107 |
Issue |
6 |
Pages |
064617 - 15pp |
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Keywords |
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Abstract |
Background: The 14N(n, p) 14C reaction is of interest in neutron capture therapy, where nitrogen-related dose is the main component due to low-energy neutrons, and in astrophysics, where 14N acts as a neutron poison in the s process. Several discrepancies remain between the existing data obtained in partial energy ranges: thermal energy, keV region, and resonance region. Purpose: We aim to measure the 14N(n, p) 14C cross section from thermal to the resonance region in a single measurement for the first time, including characterization of the first resonances, and provide calculations of Maxwellian averaged cross sections (MACS). Method: We apply the time-of-flight technique at Experimental Area 2 (EAR-2) of the neutron time-of-flight (n_TOF) facility at CERN. 10B(n, & alpha;) 7Li and 235U(n, f ) reactions are used as references. Two detection systems are run simultaneously, one on beam and another off beam. Resonances are described with the R-matrix code SAMMY. Results: The cross section was measured from subthermal energy to 800 keV, resolving the first two resonances (at 492.7 and 644 keV). A thermal cross section was obtained (1.809 & PLUSMN; 0.045 b) that is lower than the two most recent measurements by slightly more than one standard deviation, but in line with the ENDF/B-VIII.0 and JEFF-3.3 evaluations. A 1/v energy dependence of the cross section was confirmed up to tens of keV neutron energy. The low energy tail of the first resonance at 492.7 keV is lower than suggested by evaluated values, while the overall resonance strength agrees with evaluations. Conclusions: Our measurement has allowed determination of the 14N(n, p) cross section over a wide energy range for the first time. We have obtained cross sections with high accuracy (2.5%) from subthermal energy to 800 keV and used these data to calculate the MACS for kT = 5 to kT = 100 keV. |
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Address |
[Torres-Sanchez, Pablo; Praena, Javier; Porras, Ignacio; Ogallar, Francisco] Univ Granada, Granada, Spain, Email: pablotorres@ugr.es |
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Amer Physical Soc |
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English |
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2469-9985 |
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WOS:001063209900001 |
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no |
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Is ISI |
yes |
International Collaboration |
yes |
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IFIC @ pastor @ |
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5701 |
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