Records |
Author |
ATLAS Collaboration (Aad, G. et al); Alvarez Piqueras, D.; Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Jimenez Pena, J.; Kaci, M.; King, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Mitsou, V.A.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
Title |
Measurement of the charge asymmetry in top-quark pair production in the lepton-plus-jets final state in pp collision data at root s=8 TeV with the ATLAS detector |
Type |
Journal Article |
Year |
2016 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
76 |
Issue |
2 |
Pages |
87 - 30pp |
Keywords |
|
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
This paper reports inclusive and differential measurements of the t (t) over bar charge asymmetry A(C) in 20.3 fb(-1) of root s = 8 TeV pp collisions recorded by the ATLAS experiment at the Large Hadron Collider at CERN. Three differential measurements are performed as a function of the invariant mass, transverse momentum and longitudinal boost of the t (t) over bar system. The t (t) over bar pairs are selected in the single-lepton channels (e or mu) with at least four jets, and a likelihood fit is used to reconstruct the t (t) over bar event kinematics. A Bayesian unfolding procedure is performed to infer the asymmetry at parton level from the observed data distribution. The inclusive t (t) over bar charge asymmetry is measured to be A(C) = 0.009 +/- 0.005 (stat. + syst.). The inclusive and differential measurements are compatible with the values predicted by the Standard Model. |
Address |
[Aleksa, M.; Gonzalez, B. Alvarez; Anders, G.; Anghinolfi, F.; Armbruster, A. J.; Arnaez, O.; Avolio, G.; Baak, M. A.; Backes, M.; Backhaus, M.; Barak, L.; Beermann, T. A.; Beltramello, O.; Bianco, M.; Bogaerts, J. A.; Boveia, A.; Boyd, J.; Burckhart, H.; Campana, S.; Garrido, M. D. M. Capeans; Carli, T.; Carrillo-Montoya, G. D.; Catinaccio, A.; Cattai, A.; Cerv, M.; Chromek-Burckhart, D.; Conti, G.; Dell'Acqua, A.; Deviveiros, P. O.; Di Girolamo, A.; Di Girolamo, B.; Dittus, F.; Dobos, D.; Dudarev, A.; Duehrssen, M.; Eifert, T.; Ellis, N.; Elsing, M.; Farthouat, P.; Fassnacht, P.; Feigl, S.; Feng, E. J.; Perez, S. Fernandez; Francis, D.; Froidevaux, D.; Gadatsch, S.; Gillberg, D.; Glatzer, J.; Goossens, L.; Gorini, B.; Gray, H. M.; Hawkings, R. J.; Correia, A. M. Henriques; Hervas, L.; Hoecker, A.; Huhtinen, M.; Iengo, P.; Jaekel, M. R.; Jakobsen, S.; Jenni, P.; Klioutchnikova, T.; Krasznahorkay, A.; Lapoire, C.; Lassnig, M.; Miotto, G. Lehmann; Lenzi, B.; Lichard, P.; Macina, D.; Malyukov, S.; Mandelli, B.; Mapelli, L.; Marzin, A.; Milic, A.; Mornacchi, G.; Nairz, A. M.; Nakahama, Y.; Nessi, M.; Nicquevert, B.; Nordberg, M.; Oide, H.; Palestini, S.; Pauly, T.; Pernegger, H.; Peters, K.; Petersen, B. A.; Pommes, K.; Poppleton, A.; Poulard, G.; Poveda, J.; Prasad, S.; Rammensee, M.; Raymond, M.; Rembser, C.; Ritsch, E.; Roe, S.; Ruiz-Martinez, A.; Ruthmann, N.; Salzburger, A.; Schaefer, D.; Schlenker, S.; Schmieden, K.; Serfon, C.; Sforza, F.; Sfyrla, A.; Solans, C. A.; Spigo, G.; Stelzer, H. J.; Teischinger, F. A.; Ten Kate, H.; Tremblet, L.; Tricoli, A.; Tsarouchas, C.; Unal, G.; van Woerden, M. C.; Vandelli, W.; Voss, R.; Vuillermet, R.; Wells, P. S.; Wengler, T.; Wenig, S.; Werner, P.; Wilkens, H. G.; Wotschack, J.; Young, C. J. S.; Zwalinski, L.; ATLAS Collaboration] CERN, CH-1211 Geneva 23, Switzerland |
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Springer |
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English |
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ISSN |
1434-6044 |
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Expedition |
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Conference |
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Notes |
WOS:000372877800002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2587 |
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Author |
Amarilo, K.M.; Ferreira Filho, M.B.; Araujo Filho, A.A.; Reis, J.A.A.S. |
Title |
Gravitational waves effects in a Lorentz-violating scenario |
Type |
Journal Article |
Year |
2024 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
855 |
Issue |
|
Pages |
138785 - 7pp |
Keywords |
Gravitational waves; Lorentz symmetry breaking; Polarization states; Quadrupole term |
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
This paper focuses on how the production and polarization of gravitational waves are affected by spontaneous Lorentz symmetry breaking, which is driven by a self-interacting vector field. Specifically, we examine the impact of a smooth quadratic potential and a non-minimal coupling, discussing the constraints and causality features of the linearized Einstein equation. To analyze the polarization states of a plane wave, we consider a fixed vacuum expectation value (VEV) of the vector field. Remarkably, we verify that a space-like background vector field modifies the polarization plane and introduces a longitudinal degree of freedom. In order to investigate the Lorentz violation effect on the quadrupole formula, we use the modified Green function. Finally, we show that the space-like component of the background field leads to a third-order time derivative of the quadrupole moment, and the bounds for the Lorentz-breaking coefficients are estimated as well. |
Address |
[Amarilo, K. M.; Ferreira Filho, M. B.] Univ Estado Rio de Janeiro, Dep Fis Nucl & Altas Energias, Inst Fis, Rua Sao Francisco Xavier 524, BR-20559900 Rio De Janeiro, RJ, Brazil, Email: kevin.amarilo@cern.ch; |
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Elsevier |
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English |
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ISSN |
0370-2693 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001257664300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6168 |
Permanent link to this record |
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Author |
Bates, R.L. et al; Bernabeu Verdu, J.; Civera, J.V.; Gonzalez, F.; Lacasta, C.; Sanchez, J. |
Title |
The ATLAS SCT grounding and shielding concept and implementation |
Type |
Journal Article |
Year |
2012 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
Volume |
7 |
Issue |
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Pages |
P03005 |
Keywords |
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Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
This paper describes the design and implementation of the grounding and shielding system for the ATLAS SemiConductor Tracker (SCT). The mitigation of electromagnetic interference and noise pickup through power lines is the critical design goal as they have the potential to jeopardize the electrical performance. We accomplish this by adhering to the ATLAS grounding rules, by avoiding ground loops and isolating the different subdetectors. Noise sources are identified and design rules to protect the SCT against them are described. A rigorous implementation of the design was crucial to achieve the required performance. This paper highlights the location, connection and assembly of the different components that affect the grounding and shielding system: cables, filters, cooling pipes, shielding enclosure, power supplies and others. Special care is taken with the electrical properties of materials and joints. The monitoring of the grounding system during the installation period is also discussed. Finally, after connecting more than four thousand SCT modules to all of their services, electrical, mechanical and thermal within the wider ATLAS experimental environment, dedicated tests show that noise pickup is minimised. |
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Series Issue |
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Edition |
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ISSN |
1748-0221 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000304015300053 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1025 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aad, G. et al); Aikot, A.; Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Chitishvili, M.; Costa, M.J.; Didenko, M.; Escobar, C.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Lacasta, C.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valiente Moreno, E.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M. |
Title |
Measurement of the cross-sections of the electroweak and total production of a Zγ pair in association with two jets in pp collisions at √s=13 TeV with the ATLAS detector |
Type |
Journal Article |
Year |
2023 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
846 |
Issue |
|
Pages |
138222 - 30pp |
Keywords |
|
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
This Letter presents the measurement of the fiducial and differential cross-sections of the electroweak production of a Z gamma pair in association with two jets. The analysis uses 140 fb(-1)of LHC proton-proton collision data taken at root s=13 TeV recorded by the ATLAS detector during the years 2015-2018. Events with a Zboson candidate decaying into either an e(+) e(-) or mu(+) mu(-) pair, a photon and two jets are selected. The electroweak component is extracted by requiring a large dijet invariant mass and by using the information about the centrality of the system and is measured with an observed and expected significance well above five standard deviations. The fiducial pp -> Z gamma jj cross-section for the electroweak production is measured to be 3.6 +/- 0.5fb. The total fiducial cross-section that also includes contributions where the jets arise from strong interactions is measured to be 16.8(-1.8)(+2.0) fb. The results are consistent with the Standard Model predictions. Differential cross-sections are also measured using the same events and are compared with parton-shower Monte Carlo simulations. Good agreement is observed between data and predictions. |
Address |
[Filmer, E. K.; Grant, C. M.; Jackson, P.; Kong, A. X. Y.; Pandya, H. D.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
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Publisher |
Elsevier |
Place of Publication |
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Editor |
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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:001257131700001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6196 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aad, G. et al); Aikot, A.; Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Chitishvili, M.; Costa, M.J.; Didenko, M.; Escobar, C.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Lacasta, C.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Saibel, A.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valiente Moreno, E.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M. |
Title |
Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector |
Type |
Journal Article |
Year |
2024 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
132 |
Issue |
13 |
Pages |
131802 - 23pp |
Keywords |
|
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
This Letter presents the first study of Higgs boson production in association with a vector boson (V = W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in ffiffiproton-proton collisions at root root s= 13 TeV and corresponding to an integrated luminosity of 137fb(-1). The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into b (b) over bar. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ= 1.4(-0.9)(+1.0) and the corresponding cross section is 3.1 +/- 1.3(stat)(-1.4)(+1.8) (syst) pb. |
Address |
[Fedin, O. L.; Filmer, E. K.; Grant, C. M.; Jackson, P.; Kong, A. X. Y.; Kulchitsky, Y.; Myagkov, A. G.; Nikolaenko, V.; Pandya, H. D.; Potti, H.; Ruggeri, T. A.; Smirnova, L. N.; Tikhomirov, V.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
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Publisher |
Amer Physical Soc |
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 |
0031-9007 |
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:001202030300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6121 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aad, G. et al); Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Chitishvili, M.; Costa, M.J.; Didenko,, M.; Escobar, C.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Lacasta, C.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valiente Moreno, E.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M. |
Title |
Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb plus Pb Collisions at √sNN=5.02 TeV with the ATLAS Detector |
Type |
Journal Article |
Year |
2023 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
131 |
Issue |
17 |
Pages |
172301 - 22pp |
Keywords |
|
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
This letter presents a measurement of the nuclear modification factor of large-radius jets in root s(NN) = 5.02 TeV Pb thorn Pb collisions by the ATLAS experiment. The measurement is performed using 1.72 nb(-1) and 257 pb(-1) of Pb thorn Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-kt algorithm using a radius parameter of R = 1.0, by reclustering anti-k(t) R = 0.2 jets, and are measured over the transverse momentum (p(T)) kinematic range of 158 < p(T) < 1000 GeV and absolute pseudorapidity |y| < 2.0. The large-radius jet constituents are further reclustered using the k(t) algorithm in order to obtain the splitting parameters, root d(12) and Delta R-12, which characterize the transverse momentum scale and angular separation for the hardest splitting in the jet, respectively. The nuclear modification factor, R-AA, obtained by comparing the Pb thorn Pb jet yields to those in pp collisions, is measured as a function of jet transverse momentum (p(T)) and root d(12) or Delta R-12. A significant difference in the quenching of large-radius jets having single subjet and those with more complex substructure is observed. Systematic comparison of jet suppression in terms of R-AA for different jet definitions is also provided. Presented results support the hypothesis that jets with hard internal splittings lose more energy through quenching and provide a new perspective for understanding the role of jet structure in jet suppression. |
Address |
[Filmer, E. K.; Jackson, P.; Kong, A. X. Y.; Potti, H.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
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Publisher |
Amer Physical Soc |
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Editor |
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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 |
0031-9007 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001257149500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6197 |
Permanent link to this record |
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Author |
Aristizabal Sierra, D.; De Romeri, V.; Ternes, C.A. |
Title |
Reactor neutrino background in next-generation dark matter detectors |
Type |
Journal Article |
Year |
2024 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
109 |
Issue |
11 |
Pages |
115026 - 7pp |
Keywords |
|
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
Third -generation dark matter detectors will be fully sensitive to the 8 B solar neutrino flux. Because of this, the characterization of such a background has been the subject of extensive analyses over the last few years. In contrast, little is known about the impact of reactor neutrinos. In this paper, we report on the implications of such a flux for dark matter direct -detection searches. We consider five potential detector deployment sites envisioned by the recently established XLZD Consortium: SURF, SNOLAB, Kamioka, LNGS, and Boulby. By using public reactor data, we construct five reactor clusters -involving about 100 currently operating commercial nuclear reactors each -and determine the net neutrino flux at each detector site. Assuming a xenon -based detector and a 50 ton -year exposure, we show that in all cases the neutrino event rate may be sizable, depending on energy recoil thresholds. Of all possible detector sites, SURF and LNGS are those with the smallest reactor neutrino background. On the contrary, SNOLAB and Boulby are subject to the strongest reactor neutrino fluxes, with Kamioka being subject to a more moderate background. Our findings demonstrate that reactor neutrino fluxes should be taken into account in the next round of dark matter searches. We argue that this background may be particularly relevant for directional detectors, provided they meet the requirements we have employed in this analysis. |
Address |
[Sierra, D. Aristizabal] Univ Tecn Federico Santa Maria, Dept Fis, Casilla 110 V,Ave Espana 1680, Valparaiso, Chile, Email: daristizabal@uliege.be; |
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Amer Physical Soc |
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English |
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Series Editor |
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Series Issue |
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Edition |
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ISSN |
2470-0010 |
ISBN |
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Expedition |
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Conference |
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Notes |
WOS:001255433200010 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6167 |
Permanent link to this record |
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Author |
Bottoni, S. et al; Gadea, A.; Perez-Vidal, R. M. |
Title |
Search for the γ decay of the narrow near-threshold proton resonance in 11B |
Type |
Journal Article |
Year |
2024 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
855 |
Issue |
|
Pages |
138851 - 4pp |
Keywords |
11B; Near-threshold resonance; gamma-ray decay; Continuum shell model |
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
The y decay of the elusive narrow, near-threshold proton resonance in 11 B was investigated at Laboratori Nazionali di Legnaro (INFN) in a particle-y coincidence experiment, using the 6 Li( 6 Li,py) fusion-evaporation reaction and the GALILEO-GALTRACE setup. No clear signature was found for a possible E1 decay to the 1/2-1, – 1 , first-excited state of 11 B, predicted by the Shell Model Embedded in the Continuum (SMEC) with a branching of 0.98+167 +167 -69 x 10-3 -3 with respect to the dominant particle-decaying modes. The statistical analysis of the y-ray spectrum provided an average upper limit of 2.37 x 10-3 -3 for this y-ray branching, with a global significance of 5 sigma. On the other hand, by imposing a global confidence level of 3 sigma, a significant excess of counts was observed for Ey y = 9300(20) keV, corresponding to a resonance energy of 11429(20) keV (namely 200(20) keV above the proton separation energy of 11 B) and a y-ray branching of 1.12(35) x10-3. -3 . This result is compatible with the SMEC calculations, potentially supporting the existence of a near-threshold proton resonance in 11 B. |
Address |
[Bottoni, S.; Corbari, G.; Leoni, S.; Capra, S.; Albanese, E.; Ziliani, S.; Bracco, A.; Camera, F.; Crespi, F. C. L.; Gamba, E.; Polettini, M.; Porzio, C.] Univ Milano 1, Dipartimento Fis, Via Celoria 16, I-20133 Milan, Italy, Email: simone.bottoni@mi.infn.it |
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Elsevier |
Place of Publication |
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Editor |
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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:001272132000001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6205 |
Permanent link to this record |
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Author |
Forconi, M.; Giare, W.; Mena, O.; Ruchika; Di Valentino, E.; Melchiorri, A.; Nunes, R.C. |
Title |
A double take on early and interacting dark energy from JWST |
Type |
Journal Article |
Year |
2024 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
05 |
Issue |
5 |
Pages |
097 - 37pp |
Keywords |
high redshift galaxies; dark energy theory; physics of the early universe |
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
The very first light captured by the James Webb Space Telescope (JWST) revealed a population of galaxies at very high redshifts more massive than expected in the canonical Lambda CDM model of structure formation. Barring, among others, a systematic origin of the issue, in this paper, we test alternative cosmological perturbation histories. We argue that models with a larger matter component ohm m and/or a larger scalar spectral index n s can substantially improve the fit to JWST measurements. In this regard, phenomenological extensions related to the dark energy sector of the theory are appealing alternatives, with Early Dark Energy emerging as an excellent candidate to explain (at least in part) the unexpected JWST preference for larger stellar mass densities. Conversely, Interacting Dark Energy models, despite producing higher values of matter clustering parameters such as sigma 8 , are generally disfavored by JWST measurements. This is due to the energy -momentum flow from the dark matter to the dark energy sector, implying a smaller matter energy density. Upcoming observations may either strengthen the evidence or falsify some of these appealing phenomenological alternatives to the simplest Lambda CDM picture. |
Address |
[Forconi, Matteo; Melchiorri, Alessandro] Univ Roma La Sapienza, Phys Dept, Ple Aldo Moro 2, I-00185 Rome, Italy, Email: matteo.forconi@roma1.infn.it; |
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IOP Publishing Ltd |
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English |
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1475-7516 |
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WOS:001259284100005 |
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no |
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yes |
International Collaboration |
yes |
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IFIC @ pastor @ |
Serial |
6179 |
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Author |
Giarnetti, A.; Herrero-Garcia, J.; Marciano, S.; Meloni, D.; Vatsyayan, D. |
Title |
Neutrino masses from new Weinberg-like operators: phenomenology of TeV scalar multiplets |
Type |
Journal Article |
Year |
2024 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
05 |
Issue |
5 |
Pages |
055 - 37pp |
Keywords |
Baryon/Lepton Number Violation; Multi-Higgs Models |
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
The unique dimension-5 effective operator, LLHH, known as the Weinberg operator, generates tiny Majorana masses for neutrinos after electroweak spontaneous symmetry breaking. If there are new scalar multiplets that take vacuum expectation values (VEVs), they should not be far from the electroweak scale. Consequently, they may generate new dimension-5 Weinberg-like operators which in turn also contribute to Majorana neutrino masses. In this study, we consider scenarios with one or two new scalars up to quintuplet SU(2) representations. We analyse the scalar potentials, studying whether the new VEVs can be induced and therefore are naturally suppressed, as well as the potential existence of pseudo-Nambu-Goldstone bosons. Additionally, we also obtain general limits on the new scalar multiplets from direct searches at colliders, loop corrections to electroweak precision tests and the W-boson mass. |
Address |
[Giarnetti, Alessio; Marciano, Simone; Meloni, Davide] Univ Roma Tre, Dipartimento Matemat & Fis, Via Vasca Navale 84, I-00146 Rome, Italy, Email: alessio.giarnetti@uniroma3.it; |
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Springer |
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English |
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1029-8479 |
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Notes |
WOS:001255993100006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6173 |
Permanent link to this record |