Records |
Author |
Capozziello, S.; Harko, T.; Koivisto, T.S.; Lobo, F.S.N.; Olmo, G.J. |
Title |
Galactic rotation curves in hybrid metric-Palatini gravity |
Type |
Journal Article |
Year |
2013 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
50-52 |
Issue |
|
Pages |
65-75 |
Keywords |
Modified gravity; Galactic rotation curves; Dark matter |
Abstract |
Generally, the dynamics of test particles around galaxies, as well as the corresponding mass deficit, is explained by postulating the existence of a hypothetical dark matter. In fact, the behavior of the rotation curves shows the existence of a constant velocity region, near the baryonic matter distribution, followed by a quick decay at large distances. In this work, we consider the possibility that the behavior of the rotational velocities of test particles gravitating around galaxies can be explained within the framework of the recently proposed hybrid metric-Palatini gravitational theory. The latter is constructed by modifying the metric Einstein-Hilbert action with an f(R) term in the Palatini formalism. It was shown that the theory unifies local constraints and the late-time cosmic acceleration, even if the scalar field is very light. In the intermediate galactic scale, we show explicitly that in the hybrid metric-Palatini model the tangential velocity can be explicitly obtained as a function of the scalar field of the equivalent scalar-tensor description. The model predictions are compared model with a small sample of rotation curves of low surface brightness galaxies, respectively, and a good agreement between the theoretical rotation Curves and the observational data is found. The possibility of constraining the form of the scalar field and the parameters of the model by using the stellar velocity dispersions is also analyzed. Furthermore, the Doppler velocity shifts are also obtained in terms of the scalar field. All the physical and geometrical quantities and the numerical parameters in the hybrid metric-Palatini model can be expressed in terms of observable/measurable parameters, such as the tangential velocity, the baryonic mass of the galaxy, the Doppler frequency shifts, and the stellar dispersion velocity, respectively. Therefore, the obtained results open the possibility of testing the hybrid metric-Palatini gravitational models at the galactic or extra-galactic scale by using direct astronomical and astrophysical observations. |
Address |
[Capozziello, Salvatore] Univ Naples Federico II, Dipartimento Fis, Naples, Italy, Email: capozzie@na.infn.it; |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000329271000009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1689 |
Permanent link to this record |
|
|
|
Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
Title |
Identifying clouds over the Pierre Auger Observatory using infrared satellite data |
Type |
Journal Article |
Year |
2013 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
50-52 |
Issue |
|
Pages |
92-101 |
Keywords |
Ultra-high energy cosmic rays; Pierre Auger Observatory; Extensive air showers; Atmospheric monitoring; Clouds; Satellites |
Abstract |
We describe a new method of identifying night-time clouds over the Pierre Auger Observatory using infrared data from the Imager instruments on the GOES-12 and GOES-13 satellites. We compare cloud. identifications resulting from our method to those obtained by the Central Laser Facility of the Auger Observatory. Using our new method we can now develop cloud probability maps for the 3000 km(2) of the Pierre Auger Observatory twice per hour with a spatial resolution of similar to 2.4 km by similar to 5.5 km. Our method could also be applied to monitor cloud cover for other ground-based observatories and for space-based observatories. |
Address |
[Allekotte, I.; Asorey, H.; Bertou, X.; Golup, G.; Gomez Berisso, M.; Harari, D.; Mollerach, S.; Ponce, V. H.; Roulet, E.; Sidelnik, I.] Ctr Atom Bariloche, San Carlos De Bariloche, Rio Negro, Argentina |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000329271000011 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1690 |
Permanent link to this record |
|
|
|
Author |
ANTARES Collaboration (Adrian-Martinez, S. et al); Barrios-Marti, J.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Lambard, G.; Mangano, S.; Sanchez-Losa, A.; Tönnis, C.; Zornoza, J.D.; Zuñiga, J. |
Title |
Time calibration with atmospheric muon tracks in the ANTARES neutrino telescope |
Type |
Journal Article |
Year |
2016 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
78 |
Issue |
|
Pages |
43-51 |
Keywords |
Time calibration; Neutrino Telescopes; ANTARES; Atmospheric muon tracks |
Abstract |
The ANTARES experiment consists of an array of photomultipliers distributed along 12 lines and located deep underwater in the Mediterranean Sea. It searches for astrophysical neutrinos collecting the Cherenkov light induced by the charged particles, mainly muons, produced in neutrino interactions around the detector. Since at energies of similar to 10 TeV the muon and the incident neutrino are almost collinear, it is possible to use the ANTARES detector as a neutrino telescope and identify a source of neutrinos in the sky starting from a precise reconstruction of the muon trajectory. To get this result, the arrival times of the Cherenkov photons must be accurately measured. A to perform time calibrations with the precision required to have optimal performances of the instrument is described. The reconstructed tracks of the atmospheric muons in the ANTARES detector are used to determine the relative time offsets between photomultipliers. Currently, this method is used to obtain the time calibration constants for photomultipliers on different lines at a precision level of 0.5 ns. It has also been validated for calibrating photomultipliers on the same line, using a system of LEDs and laser light devices. |
Address |
[Adrian-Martinez, S.; Ardid, M.; Bou-Cabo, M.; Felis, I.; Herrero, A.; Martinez-Mora, J. A.; Saldana, M.] Univ Politecn Valencia, Inst Invest Gestio Integrada Zones Costaneres IGI, C Paranimf 1, Gandia 46730, Spain, Email: javier.barrios@ific.uv.es; |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000374612500004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2641 |
Permanent link to this record |
|
|
|
Author |
LUX-ZEPLIN Collaboration (Akerib, D.S. et al); Bailey, A.J. |
Title |
Identification of radiopure titanium for the LZ dark matter experiment and future rare event searches |
Type |
Journal Article |
Year |
2017 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
96 |
Issue |
|
Pages |
1-10 |
Keywords |
|
Abstract |
The LUX-ZEPLIN (LZ) experiment will search for dark matter particle interactions with a detector containing a total of 10 tonnes of liquid xenon within a double -vessel cryostat. The large mass and proximity of the cryostat to the active detector volume demand the use of material with extremely low intrinsic radioactivity. We report on the radioassay campaign conducted to identify suitable metals, the determination of factors limiting radiopure production, and the selection of titanium for construction of the LZ cryostat and other detector components. This titanium has been measured with activities of U-238(e) < 1.6 mBq/kg, U-238(I) < 0.09 mBq/kg, Th-232(e) = 0.28 +/- 0.03 mBq/kg, Th-232(I) = 0.25 +/- 0.02 mBq/kg, K-40 <0.54 mBq/kg, and (60) Co <0.02 mBq/kg (68% CL). Such low intrinsic activities, which are some of the lowest ever reported for titanium, enable its use for future dark matter and other rare event searches. Monte Carlo simulations have been performed to assess the expected background contribution from the LZ cryostat with this radioactivity. In 1,000 days of WIMP search exposure of a 5.6-tonne fiducial mass, the cryostat will contribute only a mean background of 0.160 +/- 0.001(stat) +/- 0.030(sys) counts. |
Address |
[Akerib, D. S.; Biesiadzinski, T. P.; Bramante, R.; Craddock, W. W.; Ignarra, C. M.; Ji, W.; Krebs, H. J.; Lee, C.; Linehan, R. E.; Luitz, S.; Mizrachi, E.; Monzani, M. E.; Ratcliff, B. N.; Shutt, T. A.; Skarpaas, K.; To, W. H.; Va'vra, J.; Whitis, T. J.; Wisniewski, W. J.] SLAC Natl Accelerator Lab, POB 20450, Stanford, CA 94309 USA, Email: sally.shaw.13@ucl.ac.uk; |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000416185400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3384 |
Permanent link to this record |
|
|
|
Author |
KM3NeT Collaboration (Aiello, S. et al); Barrios-Marti, J.; Calvo, D.; Coleiro, A.; Colomer, M.; Gozzini, S.R.; Hernandez-Rey, J.J.; Illuminati, G.; Khan Chowdhury, N.R.; Lotze, M.; Real, D.; Thakore, T.; Zornoza, J.D.; Zuñiga, J. |
Title |
Sensitivity of the KM3NeT/ARCA neutrino telescope to point-like neutrino sources |
Type |
Journal Article |
Year |
2019 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
111 |
Issue |
|
Pages |
100-110 |
Keywords |
Astrophysical neutrino sources; Cherenkov underwater neutrino telescope; KM3NeT |
Abstract |
KM3NeT will be a network of deep-sea neutrino telescopes in the Mediterranean Sea. The KM3NeT/ARCA detector, to be installed at the Capo Passero site (Italy), is optimised for the detection of high-energy neutrinos of cosmic origin. Thanks to its geographical location on the Northern hemisphere, KM3NeT/ARCA can observe upgoing neutrinos from most of the Galactic Plane, including the Galactic Centre. Given its effective area and excellent pointing resolution, KM3NeT/ARCA will measure or significantly constrain the neutrino flux from potential astrophysical neutrino sources. At the same time, it will test flux predictions based on gamma-ray measurements and the assumption that the gamma-ray flux is of hadronic origin. Assuming this scenario, discovery potentials and sensitivities for a selected list of Galactic sources and to generic point sources with an E(-2 )spectrum are presented. These spectra are assumed to be time independent. The results indicate that an observation with 3 sigma significance is possible in about six years of operation for the most intense sources, such as Supernovae Remnants RX J1713.7-3946 and Vela Jr. If no signal will be found during this time, the fraction of the gamma-ray flux coming from hadronic processes can be constrained to be below 50% for these two objects. |
Address |
[Aiello, S.; Leonora, E.; Longhitano, F.; Randazzo, N.; Tatone, F.] Ist Nazl Fis Nucl, Sez Catania, Via Santa Sofia 64, I-95123 Catania, Italy, Email: sapienza@lns.infn.it; |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000470047300008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4047 |
Permanent link to this record |
|
|
|
Author |
ANTARES Collaboration (Albert, A. et al); Barrios-Marti, J.; Hernandez-Rey, J.J.; Illuminati, G.; Lotze, M.; Tönnis, C.; Zornoza, J.D.; Zuñiga, J. |
Title |
Model-independent search for neutrino sources with the ANTARES neutrino telescope |
Type |
Journal Article |
Year |
2020 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
114 |
Issue |
|
Pages |
35-47 |
Keywords |
Neutrino astronomy; Astroparticle physics; Pattern recognition; Anisotropy |
Abstract |
A novel method to analyse the spatial distribution of neutrino candidates recorded with the ANTARES neutrino telescope is introduced, searching for an excess of neutrinos in a region of arbitrary size and shape from any direction in the sky. Techniques originating from the domains of machine learning, pattern recognition and image processing are used to purify the sample of neutrino candidates and for the analysis of the obtained skymap. In contrast to a dedicated search for a specific neutrino emission model, this approach is sensitive to a wide range of possible morphologies of potential sources of high-energy neutrino emission. The application of these methods to ANTARES data yields a large-scale excess with a post-trial significance of 2.5 sigma. Applied to public data from IceCube in its IC40 configuration, an excess consistent with the results from ANTARES is observed with a post-trial significance of 2.1 sigma. |
Address |
[Albert, A.; Drouhin, D.; Racca, C.; Saldana, M.] Univ Haute Alsace, Inst Univ Technol Colmar, GRPHE, 34 Rue Grillenbreit,BP Colmar 50568, F-68008 Mulhouse, France, Email: stefan.geisselsoeder@fau.de; |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000489353300005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4167 |
Permanent link to this record |
|
|
|
Author |
Di Valentino, E. et al; Mena, O. |
Title |
Snowmass2021-Letter of interest cosmology intertwined II: The hubble constant tension |
Type |
Journal Article |
Year |
2021 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
131 |
Issue |
|
Pages |
102605 - 8pp |
Keywords |
|
Abstract |
The current cosmological probes have provided a fantastic confirmation of the standard A Cold Dark Matter cosmological model, which has been constrained with unprecedented accuracy. However, with the increase of the experimental sensitivity, a few statistically significant tensions between different independent cosmological datasets emerged. While these tensions can be in part the result of systematic errors, the persistence after several years of accurate analysis strongly hints at cracks in the standard cosmological scenario and the need for new physics. In this Letter of Interest we will focus on the 4.4 sigma – tension between the Planck estimate of the Hubble constant H-0 and the SH0ES collaboration measurements. After showing the H-0 evaluations made from different teams using different methods and geometric calibrations, we will list a few interesting models of new physics that could solve this tension and discuss how the next decade's experiments will be crucial. |
Address |
[Di Valentino, Eleonora; Chluba, Jens; Harrison, Ian; Hart, Luke; Pace, Francesco] Univ Manchester, JBCA, Manchester, Lancs, England, Email: eleonora.di-valentino@durham.ac.uk |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000657813100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4853 |
Permanent link to this record |
|
|
|
Author |
Di Valentino, E. et al; Mena, O. |
Title |
Cosmology intertwined III: f sigma(8) and S-8 |
Type |
Journal Article |
Year |
2021 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
131 |
Issue |
|
Pages |
102604 - 6pp |
Keywords |
cosmological tensions; cosmological parameters |
Abstract |
The standard A Cold Dark Matter cosmological model provides a wonderful fit to current cosmological data, but a few statistically significant tensions and anomalies were found in the latest data analyses. While these anomalies could be due to the presence of systematic errors in the experiments, they could also indicate the need for new physics beyond the standard model. In this Letter of Interest we focus on the tension between Planck data and weak lensing measurements and redshift surveys, in the value of the matter energy density Omega(m), and the amplitude sigma(8) (or the growth rate f sigma(8)) of cosmic structure. We list a few promising models for solving this tension, and discuss the importance of trying to fit multiple cosmological datasets with complete physical models, rather than fitting individual datasets with a few handpicked theoretical parameters. |
Address |
[Di Valentino, Eleonora; Chluba, Jens; Harrison, Ian; Hart, Luke; Pace, Francesco] Univ Manchester, JBCA, Manchester, Lancs, England, Email: eleonora.di-valentino@durham.ac.uk |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000657813100006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4854 |
Permanent link to this record |
|
|
|
Author |
Di Valentino, E. et al; Mena, O. |
Title |
Snowmass2021-Letter of interest cosmology intertwined IV: The age of the universe and its curvature |
Type |
Journal Article |
Year |
2021 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
131 |
Issue |
|
Pages |
102607 - 5pp |
Keywords |
|
Abstract |
A precise measurement of the curvature of the Universe is of prime importance for cosmology since it could not only confirm the paradigm of primordial inflation but also help in discriminating between different early-Universe scenarios. Recent observations, while broadly consistent with a spatially flat standard A Cold Dark Matter (ACDM) model, show tensions that still allow (and, in some cases, even suggest) a few percent deviations from a flat universe. In particular, the Planck Cosmic Microwave Background power spectra, assuming the nominal likelihood, prefer a closed universe at more than 99% confidence level. While new physics could be at play, this anomaly may be the result of an unresolved systematic error or just a statistical fluctuation. However, since positive curvature allows a larger age of the Universe, an accurate determination of the age of the oldest objects provides a smoking gun in confirming or falsifying the current flat ACDM model. |
Address |
[Di Valentino, Eleonora; Chluba, Jens; Harrison, Ian; Hart, Luke; Pace, Francesco] Univ Manchester, JBCA, Manchester, Lancs, England, Email: eleonora.di-valentino@durham.ac.uk |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000657813100007 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4855 |
Permanent link to this record |
|
|
|
Author |
Di Valentino, E. et al; Mena, O. |
Title |
Snowmass2021-Letter of interest cosmology intertwined I: Perspectives for the next decade |
Type |
Journal Article |
Year |
2021 |
Publication  |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
131 |
Issue |
|
Pages |
102606 - 4pp |
Keywords |
|
Abstract |
The standard Lambda Cold Dark Matter cosmological model provides an amazing description of a wide range of astrophysical and astronomical data. However, there are a few big open questions, that make the standard model look like a first-order approximation to a more realistic scenario that still needs to be fully understood. In this Letter of Interest we will list a few important goals that need to be addressed in the next decade, also taking into account the current discordances present between the different cosmological probes, as the Hubble constant H-0 value, the sigma S-8(8) tension, and the anomalies present in the Planck results. Finally, we will give an overview of upgraded experiments and next-generation space-missions and facilities on Earth that will be of crucial importance to address all these questions. |
Address |
[Di Valentino, Eleonora; Chluba, Jens; Harrison, Ian; Hart, Luke; Pace, Francesco] Univ Manchester, JBCA, Manchester, Lancs, England, Email: eleonora.di-valentino@durham.ac.uk |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-6505 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000657813100003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4856 |
Permanent link to this record |