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Author Jueid, A.; Kip, J.; Ruiz de Austri, R.; Skands, P.
Title Impact of QCD uncertainties on antiproton spectra from dark-matter annihilation Type Journal Article
Year 2023 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 068 - 15pp
Keywords cosmic ray theory; dark matter simulations; cosmic ray experiments; Frequentist statistics
Abstract Dark-matter particles that annihilate or decay can undergo complex sequences of processes, including strong and electromagnetic radiation, hadronisation, and hadron de-cays, before particles that are stable on astrophysical time scales are produced. Antiprotons produced in this way may leave footprints in experiments such as AMS-02. Several groups have reported an excess of events in the antiproton flux in the rigidity range of 10-20 GV. However, the theoretical modeling of baryon production is not straightforward and relies in part on phenomenological models in Monte Carlo event generators. In this work, we assess the impact of QCD uncertainties on the spectra of antiprotons from dark-matter annihila-tion. As a proof-of-principle, we show that for a two-parameter model that depends only on the thermally-averaged annihilation cross section ((o -v)) and the dark-matter mass (Mx), QCD uncertainties can affect the best-fit mass by up to ti 14% (with large uncertainties for large DM masses), depending on the choice of Mx and the annihilation channel (bb over bar or W+W-), and (o -v) by up to ti 10%. For comparison, changes to the underlying diffusion parameters are found to be within 1%-5%, and the results are also quite resilient to the choice of cosmic-ray propagation model. These findings indicate that QCD uncertainties need to be included in future DM analyses. To facilitate full-fledged analyses, we provide the spectra in tabulated form including QCD uncertainties and code snippets to perform mass interpolations and quick DM fits. The code can be found in this GitHub [1] repository.
Address (up) [Jueid, Adil] Inst Basic Sci IBS, Ctr Theoret Phys Universe, Daejeon 34126, South Korea, Email: adiljueid@ibs.re.kr;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000985779900007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5532
Permanent link to this record
 
 
Author Kim, J.; Ko, P.; Park, W.I.
Title Higgs-portal assisted Higgs inflation with a sizeable tensor-to-scalar ratio Type Journal Article
Year 2017 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 02 Issue 2 Pages 003 - 16pp
Keywords inflation; particle physics – cosmology connection; physics of the early universe
Abstract We show that the Higgs portal interactions involving extra dark Higgs field can save generically the original Higgs inflation of the standard model (SM) from the problem of a deep non-SM vacuum in the SM Higgs potential. Specifically, we show that such interactions disconnect the top quark pole mass from inflationary observables and allow multi-dimensional parameter space to save the Higgs inflation, thanks to the additional parameters (the dark Higgs boson mass m(phi), the mixing angle a between the SM Higgs H and dark Higgs Phi, and the mixed quartic coupling) affecting RG-running of the Higgs quartic coupling. The effect of Higgs portal interactions may lead to a larger tensor-to-scalar ratio, 0.08 less than or similar to r less than or similar to 0.1, by adjusting relevant parameters in wide ranges of alpha and m(phi), some region of which can be probed at future colliders. Performing a numerical analysis we find an allowed region of parameters, matching the latest Planck data.
Address (up) [Kim, Jinsu; Ko, Pyungwon] Korea Inst Adv Study, Quantum Universe Ctr, 85 Hoegiro Dongdaemungu, Seoul 02455, South Korea, Email: kimjinsu@kias.re.kr;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000399455000003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3080
Permanent link to this record
 
 
Author Kim, J.S.; Lopez-Fogliani, D.E.; Perez, A.D.; Ruiz de Austri, R.
Title Right-handed sneutrino and gravitino multicomponent dark matter in light of neutrino detectors Type Journal Article
Year 2023 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 050 - 32pp
Keywords dark matter theory; dark matter experiments; neutrino detectors
Abstract We investigate the possibility that right-handed (RH) sneutrinos and gravitinos can coexist and explain the dark matter (DM) problem. We compare extensions of the minimal supersymmetric standard model (MSSM) and the next-to-MSSM (NMSSM) adding RH neutrinos superfields, with special emphasis on the latter. If the gravitino is the lightest supersymmetric particle (LSP) and the RH sneutrino the next-to-LSP (NLSP), the heavier particle decays to the former plus left-handed (LH) neutrinos through the mixing between the scalar partners of the LH and RH neutrinos. However, the interaction is suppressed by the Planck mass, and if the LH-RH sneutrino mixing parameter is small, << O(10-2), a long-lived RH sneutrino NLSP is possible even surpassing the age of the Universe. As a byproduct, the NLSP to LSP decay produces monochromatic neutrinos in the ballpark of current and planned neutrino telescopes like Super-Kamiokande, IceCube and Antares that we use to set constraints and show prospects of detection. In the NMSSM+RHN, assuming a gluino mass parameter M3 = 3 TeV we found the following lower limits for the gravitino mass m3/2 >= 1-600 GeV and the reheating temperature TR >= 105-3 x 107 GeV, for m nu similar to R similar to 10-800 GeV. If we take M3 = 10 TeV, then the limits on TR are relaxed by one order of magnitude.
Address (up) [Kim, Jong Soo] Univ Witwatersrand, Sch Phys, Johannesburg, South Africa, Email: jongsoo.kim@tu-dortmund.de;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000975382300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5523
Permanent link to this record
 
 
Author Kuo, J.L.; Lattanzi, M.; Cheung, K.; Valle, J.W.F.
Title Decaying warm dark matter and structure formation Type Journal Article
Year 2018 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 12 Issue 12 Pages 026 - 24pp
Keywords cosmological simulations; dark matter simulations
Abstract We examine the cosmology of warm dark matter (WDM), both stable and decaying, from the point of view of structure formation. We compare the matter power spectrum associated to WDM masses of 1.5 keV and 0.158 keV, with that expected for the stable cold dark matter ACDM Xi SCDM paradigm, taken as our reference model. We scrutinize the effects associated to the warm nature of dark matter, as well as the fact that it decays. The decaying warm dark matter (DWDM) scenario is well-motivated, emerging in a broad class of particle physics theories where neutrino masses arise from the spontaneous breaking of a continuous global lepton number symmetry. The majoron arises as a Nambu-Goldstone boson, and picks up a mass from gravitational effects, that explicitly violate global symmetries. The majoron necessarily decays to neutrinos, with an amplitude proportional to their tiny mass, which typically gives it cosmologically long lifetimes. Using N-body simulations we show that our DWDM picture leads to a viable alternative to the ACDM scenario, with predictions that can differ substantially on small scales.
Address (up) [Kuo, Jui-Lin; Cheung, Kingman] Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan, Email: juilinkuo@gapp.nthu.edu.tw;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000453858100005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3851
Permanent link to this record
 
 
Author Lessa, L.A.; Maluf, R.V.; Silva, J.E.G.; Almeida, C.A.S.
Title Braneworlds in warped Einsteinian cubic gravity Type Journal Article
Year 2024 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 05 Issue 5 Pages 123 - 25pp
Keywords Gauss-Bonnet-Lovelock-Horndeski-Palatini etc gravity theories; gravity; modified gravity
Abstract Einstenian cubic gravity (ECG) is a modified theory of gravity constructed with cubic contractions of the curvature tensor. This theory has the remarkable feature of having the same two propagating degrees of freedom of Einstein gravity (EG), at the perturbative level on maximally symmetric spacetimes. The additional unstable modes steaming from the higher order derivative dynamics are suppressed provided that we consider the ECG as an effective field theory wherein the cubic terms are seen as perturbative corrections of the Einstein -Hilbert term. Extensions of ECG have been proposed in cosmology and compact objects in order to probe if this property holds in more general configurations. In this work, we construct a modified ECG gravity in a five dimensional warped braneworld scenario. By assuming a specific combination of the cubic parameters, we obtained modified gravity equations of motion with terms up to second -order. For a thin 3-brane, the cubic -gravity corrections yield an effective positive bulk cosmological constant. Thus, in order to keep the 5D bulk warped compact, an upper bound of the cubic parameter with respect to the bulk curvature was imposed. For a thick brane, the cubic -gravity terms modify the scalar field potential and its corresponding vacuum. Nonetheless, the domain -wall structure with a localized source is preserved. At the perturbative level, the Kaluza-Klein (KK) tensor gravitational modes are stable and possess a localized massless mode provided the cubic corrections are small compared to the EG braneworld.
Address (up) [Lessa, L. A.; Maluf, R. V.; Silva, J. E. G.; Almeida, C. A. S.] Univ Fed Ceara UFC, Dept Fis, Campus Pici, BR-60455760 Fortaleza, CE, Brazil, Email: leandrolessa@fisica.ufc.br;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:001240966600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6164
Permanent link to this record
 
 
Author Lineros, R.A.; Pereira dos Santos, F.A.
Title Inert scalar dark matter in an extra dimension inspired model Type Journal Article
Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 10 Issue 10 Pages 059 - 17pp
Keywords dark matter theory; extra dimensions; particle physics – cosmology connection
Abstract In this paper we analyze a dark matter model inspired by theories with extra dimensions. The dark matter candidate corresponds to the first Kaluza-Klein mode of an real scalar added to the Standard Model. The tower of new particles enriches the calculation of the relic abundance. For large mass splitting, the model converges to the predictions of the inert singlet dark matter model. For nearly degenerate mass spectrum, coannihilations increase the cross-sections used for direct and indirect dark matter searches. Moreover, the Kaluza-Klein zero mode can mix with the SM higgs and further constraints can be applied.
Address (up) [Lineros, R. A.; Pereira dos Santos, F. A.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46980 Paterna, Spain, Email: rlineros@ific.uv.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000345990800060 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2042
Permanent link to this record
 
 
Author Lobo, F.S.N.; Olmo, G.J.; Rubiera-Garcia, D.
Title Semiclassical geons as solitonic black hole remnants Type Journal Article
Year 2013 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 011 - 10pp
Keywords modified gravity; primordial black holes; Wormholes; quantum field theory on curved space
Abstract We find that the end state of black hole evaporation could be represented by non-singular and without event horizon stable solitonic remnants with masses of the order the Planck scale and up to similar to 16 units of charge. Though these objects are locally indistinguishable from spherically symmetric, massive electric (or magnetic) charges, they turn out to be sourceless geons containing a wormhole generated by the electromagnetic field. Our results are obtained by interpreting semiclassical corrections to Einstein's theory in the first-order (Palatini) formalism, which yields second-order equations and avoids the instabilities of the usual (metric) formulation of quadratic gravity. We also discuss the potential relevance of these solutions for primordial black holes and the dark matter problem.
Address (up) [Lobo, Francisco S. N.] Univ Lisbon, Ctr Astron & Astrofis, P-1749016 Lisbon, Portugal, Email: flobo@cii.fc.ul.pt;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000322582000012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1532
Permanent link to this record
 
 
Author Lopez Honorez, L.; Reid, B.A.; Mena, O.; Verde, L.; Jimenez, R.
Title Coupled dark matter-dark energy in light of near universe observations Type Journal Article
Year 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 09 Issue 9 Pages 029 - 36pp
Keywords dark energy experiments; dark energy theory; cosmological parameters from LSS
Abstract Cosmological analysis based on currently available observations are unable to rule out a sizeable coupling among the dark energy and dark matter fluids. We explore a variety of coupled dark matter-dark energy models, which satisfy cosmic microwave background constraints, in light of low redshift and near universe observations. We illustrate the phenomenology of different classes of dark coupling models, paying particular attention in distinguishing between effects that appear only on the expansion history and those that appear in the growth of structure. We find that while a broad class of dark coupling models are effectively models where general relativity (GR) is modified – and thus can be probed by a combination of tests for the expansion history and the growth of structure -, there is a class of dark coupling models where gravity is still GR, but the growth of perturbations is, in principle modified. While this effect is small in the specific models we have considered, one should bear in mind that an inconsistency between reconstructed expansion history and growth may not uniquely indicate deviations from GR. Our low redshift constraints arise from cosmic velocities, redshift space distortions and dark matter abundance in galaxy voids. We find that current data constrain the dimensionless coupling to be vertical bar xi vertical bar < 0.2, but prospects from forthcoming data are for a significant improvement. Future, precise measurements of the Hubble constant, combined with high-precision constraints on the growth of structure, could provide the key to rule out dark coupling models which survive other tests. We shall exploit as well weak equivalence principle violation arguments, which have the potential to highly disfavour a broad family of coupled models.
Address (up) [Lopez Honorez, Laura] UAM, CSIC, Dept Phys, Madrid 28049, Spain, Email: laura.lopez@uam.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes ISI:000283576500007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 343
Permanent link to this record
 
 
Author Lopez-Fogliani, D.E.; Perez, A.D.; Ruiz de Austri, R.
Title Dark matter candidates in the NMSSM with RH neutrino superfields Type Journal Article
Year 2021 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 067 - 35pp
Keywords dark matter theory; dark matter detectors
Abstract R-parity conserving supersymmetric models with right-handed (RH) neutrinos are very appealing since they could naturally explain neutrino physics and also provide a good dark matter (DM) candidate such as the lightest supersymmetric particle (LSP). In this work we consider the next-to-minimal supersymmetric standard model (NMSSM) plus RH neutrino superfields, with effective Majorana masses dynamically generated at the electroweak scale (EW). We perform a scan of the relevant parameter space and study both possible DM candidates: RH sneutrino and neutralino. Especially for the case of RH sneutrino DM we analyse the intimate relation between both candidates to obtain the correct amount of relic density. Besides the well-known resonances, annihilations through scalar quartic couplings and coannihilation mechanisms with all kind of neutralinos, are crucial. Finally, we present the impact of current and future direct and indirect detection experiments on both DM candidates.
Address (up) [Lopez-Fogliani, Daniel E.] Univ Buenos Aires, Fac Ciencia Exactas & Nat, Inst Fis Buenos Aires UBA, RA-1428 Buenos Aires, DF, Argentina, Email: daniel.lopez@df.uba.ar;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000644501000049 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4824
Permanent link to this record
 
 
Author Lopez-Honorez, L.; Mena, O.; Palomares-Ruiz, S.; Villanueva-Domingo, P.; Witte, S.J.
Title Variations in fundamental constants at the cosmic dawn Type Journal Article
Year 2020 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 06 Issue 6 Pages 026 - 25pp
Keywords cosmology of theories beyond the SM; particle physics – cosmology connection; reionization
Abstract The observation of space-time variations in fundamental constants would provide strong evidence for the existence of new light degrees of freedom in the theory of Nature. Robustly constraining such scenarios requires exploiting observations that span different scales and probe the state of the Universe at different epochs. In the context of cosmology, both the cosmic microwave background and the Lyman-a forest have proven to be powerful tools capable of constraining variations in electromagnetism, however at the moment there do not exist cosmological probes capable of bridging the gap between recombination and reionization. In the near future, radio telescopes will attempt to measure the 21 cm transition of neutral hydrogen during the epochs of reionization and the cosmic dawn (and potentially the tail end of the dark ages); being inherently sensitive to electromagnetic phenomena, these experiments will offer a unique perspective on space-time variations of the fine-structure constant and the electron mass. We show here that large variations in these fundamental constants would produce features on the 21 cm power spectrum that may be distinguishable from astrophysical uncertainties. Furthermore, we forecast the sensitivity for the Square Kilometer Array, and show that the 21 cm power spectrum may be able to constrain variations at the level of O(10(-3)).
Address (up) [Lopez-Honorez, Laura] Univ Libre Bruxelles, Serv Phys Theor, CP225, B-1050 Brussels, Belgium, Email: llopezho@ulb.ac.be;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000551875400049 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4473
Permanent link to this record