Records |
Author |
Olmo, G.J.; Rubiera-Garcia, D.; Wojnar, A. |
Title |
Stellar structure models in modified theories of gravity: Lessons and challenges |
Type |
Journal Article |
Year |
2020 |
Publication |
Physics Reports |
Abbreviated Journal |
Phys. Rep. |
Volume |
876 |
Issue |
|
Pages |
1-75 |
Keywords |
Stellar structure; Modified gravity; Palatini formalism; Neutron stars; Brown dwarfs; Relativistic stars; Weak field; f(R) theories; Born-Infeld theory; Horndeski theory |
Abstract |
The understanding of stellar structure represents the crossroads of our theories of the nuclear force and the gravitational interaction under the most extreme conditions observably accessible. It provides a powerful probe of the strong field regime of General Relativity, and opens fruitful avenues for the exploration of new gravitational physics. The latter can be captured via modified theories of gravity, which modify the Einstein-Hilbert action of General Relativity and/or some of its principles. These theories typically change the Tolman-Oppenheimer-Volkoff equations of stellar's hydrostatic equilibrium, thus having a large impact on the astrophysical properties of the corresponding stars and opening a new window to constrain these theories with present and future observations of different types of stars. For relativistic stars, such as neutron stars, the uncertainty on the equation of state of matter at supranuclear densities intertwines with the new parameters coming from the modified gravity side, providing a whole new phenomenology for the typical predictions of stellar structure models, such as mass-radius relations, maximum masses, or moment of inertia. For non-relativistic stars, such as white, brown and red dwarfs, the weakening/strengthening of the gravitational force inside astrophysical bodies via the modified Newtonian (Poisson) equation may induce changes on the star's mass, radius, central density or luminosity, having an impact, for instance, in the Chandrasekhar's limit for white dwarfs, or in the minimum mass for stable hydrogen burning in high-mass brown dwarfs. This work aims to provide a broad overview of the main such results achieved in the recent literature for many such modified theories of gravity, by combining the results and constraints obtained from the analysis of relativistic and non-relativistic stars in different scenarios. Moreover, we will build a bridge between the efforts of the community working on different theories, formulations, types of stars, theoretical modelings, and observational aspects, highlighting some of the most promising opportunities in the field. |
Address |
[Olmo, Gonzalo J.] Univ Valencia, Dept Fis Teor, Ctr Mixto, CSIC, Valencia 46100, Spain, Email: gonzalo.olmo@uv.es; |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
0370-1573 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000570298900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4531 |
Permanent link to this record |
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Author |
AGATA Collaboration (Siciliano, M. et al); Gadea, A.; Perez-Vidal, R.M.; Domingo-Pardo, C. |
Title |
Pairing-quadrupole interplay in the neutron-deficient tin nuclei: First lifetime measurements of low-lying states in Sn-106,Sn-108 |
Type |
Journal Article |
Year |
2020 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
806 |
Issue |
|
Pages |
135474 - 7pp |
Keywords |
Lifetime; Nuclear structure; Multi-nucleon transfer; Light Sn; Tracking array |
Abstract |
The lifetimes of the low-lying excited states 2(+) and 4(+) have been directly measured in the neutron-deficient Sn-106,Sn-108 isotopes. The nuclei were populated via a deep-inelastic reaction and the lifetime measurement was performed employing a differential plunger device. The emitted gamma rays were detected by the AGATA array, while the reaction products were uniquely identified by the VAMOS++ magnetic spectrometer. Large-Scale Shell-Model calculations with realistic forces indicate that, independently of the pairing content of the interaction, the quadrupole force is dominant in the B(E2; 2(1)(+) -> 0(g.s)(+)) values and it describes well the experimental pattern for Sn104-114 ; the B(E2;(+)(4) -> 2(1)(+)) values, measured here for the first time, depend critically on a delicate pairing-quadrupole balance, disclosed by the very precise results in Sn-108. |
Address |
[Siciliano, M.; Valiente-Dobon, J. J.; Goasduff, A.; Jaworski, G.; Marchi, T.; Napoli, D. R.; Saygi, B.; Egea-Canet, F. J.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, Legnaro, PD, Italy, Email: marco.siciliano@lnl.infn.it |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000571760900006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4539 |
Permanent link to this record |
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Author |
Azevedo, C.D.R.; Baeza, A.; Chauveau, E.; Corbacho, J.A.; Diaz, J.; Domange, J.; Marquet, C.; Martinez-Roig, M.; Piquemal, F.; Veloso, J.F.C.A.; Yahlali, N. |
Title |
Simulation results of a real-time in water tritium monitor |
Type |
Journal Article |
Year |
2020 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
982 |
Issue |
|
Pages |
164555 - 7pp |
Keywords |
Tritium in water; Real-time monitor; Nuclear power plant; Environmental safety |
Abstract |
In this work we present simulation results for a modular tritium in-water real-time monitor. The system allows for scalability in order to achieve the required sensitivity. The modules are composed by 340 uncladed scintillating fibers immersed in water and 2 photosensors in coincidence for light readout. Light yield and Birks' coefficient uncertainties for low energy beta particles is discussed. A study of the detection efficiency according to the fiber length is presented. Discussion on the system requirements and background mitigation for a device with sensitivity of 100 Bq/L, required to comply with the European directive 2013/51/Euratom, is presented. Due to the low energetic beta emission from tritium a detection efficiency close to 3.3% was calculated for a single 2 mm round fiber. |
Address |
[Azevedo, C. D. R.; Veloso, J. F. C. A.] Univ Aveiro, Dept Phys, I3N, Campus Univ Santiago, P-3810193 Aveiro, Portugal, Email: cdazevedo@ua.pt |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
|
Edition |
|
ISSN |
0168-9002 |
ISBN |
|
Medium |
|
Area |
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Expedition |
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Conference |
|
Notes |
WOS:000581805300016 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4578 |
Permanent link to this record |
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Author |
Fernandez-Tejero, J.; Bartl, U.; Docke, M.; Fadeyev, V.; Fleta, C.; Hacker, J.; Hommels, B.; Lacasta, C.; Parzefall, U.; Soldevila, U.; Stocker, G.; Ullan, M.; Unno, Y. |
Title |
Design and evaluation of large area strip sensor prototypes for the ATLAS Inner Tracker detector |
Type |
Journal Article |
Year |
2020 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
981 |
Issue |
|
Pages |
164536 - 6pp |
Keywords |
ATLAS; Silicon strip sensors; Large area silicon sensors; Layout design; Prototype evaluation; Market survey |
Abstract |
The ATLAS community is facing the last stages prior to the production of the upgraded silicon strip Inner Tracker for the High-Luminosity Large Hadron Collider. An extensive Market Survey was carried out in order to evaluate the capability of different foundries to fabricate large area silicon strip sensors, satisfying the ATLAS specifications. The semiconductor manufacturing company, Infineon Technologies AG, was one of the two foundries, along with Hamamatsu Photonics K.K., that reached the last stage of the evaluation for the production of the new devices. The full prototype wafer layout for the participation of Infineon, called ATLAS17LS-IFX, was designed using a newly developed Python-based Automatic Layout Generation Tool, able to rapidly design sensors with different characteristics and dimensions based on a few geometrical and technological input parameters. This work presents the layout design process and the results obtained from the evaluation of the new Infineon large area sensors before and after proton and neutron irradiations, up to fluences expected in the inner layers of the future ATLAS detector. |
Address |
[Fernandez-Tejero, J.; Fleta, C.; Ullan, M.] CSIC, Ctr Nacl Microelect IMB CNM, Campus UAB Bellaterra, Barcelona 08193, Spain, Email: Xavi.Fdez@cern.ch |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
0168-9002 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000581799800023 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4579 |
Permanent link to this record |
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Author |
Dias, A.G.; Leite, J.; Valle, J.W.F.; Vaquera-Araujo, C.A. |
Title |
Reloading the axion in a 3-3-1 setup |
Type |
Journal Article |
Year |
2020 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
810 |
Issue |
|
Pages |
135829 - 12pp |
Keywords |
Peccei-Quinn symmetry; Axion; Neutrinos |
Abstract |
We generalize the idea of the axion to an extended electroweak gauge symmetry setup. We propose a minimal axion extension of the Singer-Valle-Schechter (SVS) theory, in which the standard model fits in SU(3)(L) circle times U(1)(X), the number of families results from anomaly cancellation, and the Peccei-Quinn (PQ) solution to the strong-CP problem is implemented. Neutrino masses arise from a type-I Dirac seesaw mechanism, suppressed by the ratio of SVS and PQ scales, suggesting the existence of new physics at a moderate SVS scale. Novel features include an enhanced axion coupling to photons when compared to the DFSZ axion, as well as flavor-changing axion couplings to quarks. |
Address |
[Dias, Alex G.; Leite, Julio] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210580 Santo Andre, SP, Brazil, Email: alex.dias@ufabc.edu.br; |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
0370-2693 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000582969900048 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4586 |
Permanent link to this record |