|   | 
Details
   web
Records
Author Alvarez-Ortega, D.; Olmo, G.J.; Rubiera-Garcia, D.; Saez-Chillon Gomez, D.
Title Eternal versus singular observers in interacting dark-energy-dark-matter models Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 106 Issue 2 Pages 023523 - 14pp
Keywords (up)
Abstract Interacting dark-energy-dark-matter models have been widely analyzed in the literature in an attempt to find traces of new physics beyond the usual cosmological (Lambda CDM) models. Such a coupling between both dark components is usually introduced in a phenomenological way through a flux in the continuity equation. However, models with a Lagrangian formulation are also possible. A class of the latter assumes a conformal/disformal coupling that leads to a fifth force on the dark-matter component, which consequently does not follow the same geodesics as the other (baryonic, radiation, and dark-energy) matter sources. Here we analyze how the usual cosmological singularities of the standard matter frame are seen from the dark-matter one, concluding that by choosing an appropriate coupling, dark-matter observers will see no singularities but a non beginning, non ending universe. By considering two simple phenomenological models we show that such a type of coupling can fit observational data as well as the usual Lambda CDM model.
Address [Alvarez-Ortega, Diego] Inst Fis Cantabria CSIC UC, Avda Castros S-N, Santander 39005, Spain, Email: diego.alvarezo@alumnos.unican.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000842768300012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5345
Permanent link to this record
 

 
Author AGATA Collaboration (Rezynkina, K. et al); Gadea, A.; Perez-Vidal, R.M.
Title Structure of As-83, As- 85, and As-87: From semimagicity to gamma softness Type Journal Article
Year 2022 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 106 Issue 1 Pages 014320 - 14pp
Keywords (up)
Abstract The structure of As-83,As- 85, and As-87 have been studied in fusion-fission reaction( 238)U+9Be. Fission fragments were identified in mass and atomic number using the VAMOS++ spectrometer and the coincident gamma rays were detected in the gamma-ray tracking array AGATA. New transitions in 83As and 85As are reported and placed in the level schemes. A level scheme of the excited states in 87As is proposed for the first time. The data are interpreted in frame of large-scale shell-model calculations, SU3 symmetries, and beyond mean-field frameworks. A spherical regime at magic number N = 50 is predicted and the location of the proton g9/2 orbital is proposed for the first time. Development of collectivity in a prolate deformed, gamma-soft regime in the open shell cases 85As and 87As, most neutron-rich isotopes beyond N = 50, is concluded. Data and theoretical calculations give confidence to a relatively high extrapolated excitation energy about 4 MeV of the 9/2+ state in 79Cu, one proton above 78Ni.
Address [Rezynkina, K.; Dao, D. D.; Duchene, G.; Nowacki, F.; Didierjean, F.; Le Blanc, F.; Lozeva, R.; Schmitt, C.] Univ Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France, Email: kseniia.rezynkina@pd.infn.it
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000848175600004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5347
Permanent link to this record
 

 
Author Guerrero, M.; Olmo, G.J.; Rubiera-Garcia, D.; Saez-Chillon Gomez, D.
Title Multiring images of thin accretion disk of a regular naked compact object Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 106 Issue 4 Pages 044070 - 13pp
Keywords (up)
Abstract We discuss the importance of multiring images in the optical appearance of a horizonless spherically symmetric compact object, when illuminated by an optically thin accretion disk. Such an object corresponds to a subcase of an analytically tractable extension of the Kerr solution dubbed as the “eye of the storm” by Simpson and Visser in [J. Cosmol. Astropart. Phys. 03 (2022) 011], which merits in removing curvature singularities via an asymptotically Minkowski core, while harboring both a critical curve and an infinite potential barrier at the center for null geodesics. This multiring structure is induced by light rays winding several times around the object, and whose luminosity is significantly boosted as compared to the Schwarzschild solution by the modified shape of the potential. Using three toy profiles for the emission of an infinitely thin disk, truncated at its inner edge (taking its maximum value there) and having different decays with the distance, we discuss the image created by up to eight rings superimposed on top of the direct emission of the disk as its edge is moved closer to the center of the object. Our results point to the existence of multiring images with a non-negligible luminosity in shadow observations when one allows for the existence of other compact objects in the cosmic zoo beyond the Schwarzschild solution. Such multiring images could be detectable within the future projects on very long baseline interferometry.
Address [Guerrero, Merce; Rubiera-Garcia, Diego] Univ Complutense Madrid, Dept Fis Teor, IPARCOS, Madrid 28040, Spain, Email: merguerr@ucm.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000850772800006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5352
Permanent link to this record
 

 
Author Kiss, G.G. et al; Tarifeño-Saldivia, A.; Tain, J.L.; Agramunt, J.; Algora, A.; Domingo-Pardo, C.; Morales, A.I.; Nacher, E.; Rubio, B.; Tolosa, A.
Title Measuring the beta-decay Properties of Neutron-rich Exotic Pm, Sm, Eu, and Gd Isotopes to Constrain the Nucleosynthesis Yields in the Rare-earth Region Type Journal Article
Year 2022 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.
Volume 936 Issue 2 Pages 107 - 18pp
Keywords (up)
Abstract The beta-delayed neutron-emission probabilities of 28 exotic neutron-rich isotopes of Pm, Sm, Eu, and Gd were measured for the first time at RIKEN Nishina Center using the Advanced Implantation Detector Array (AIDA) and the BRIKEN neutron detector array. The existing beta-decay half-life (T (1/2)) database was significantly increased toward more neutron-rich isotopes, and uncertainties for previously measured values were decreased. The new data not only constrain the theoretical predictions of half-lives and beta-delayed neutron-emission probabilities, but also allow for probing the mechanisms of formation of the high-mass wing of the rare-earth peak located at A approximate to 160 in the r-process abundance distribution through astrophysical reaction network calculations. An uncertainty quantification of the calculated abundance patterns with the new data shows a reduction of the uncertainty in the rare-earth peak region. The newly introduced variance-based sensitivity analysis method offers valuable insight into the influence of important nuclear physics inputs on the calculated abundance patterns. The analysis has identified the half-lives of Sm-168 and of several gadolinium isotopes as some of the key variables among the current experimental data to understand the remaining abundance uncertainty at A = 167-172.
Address [Kiss, G. G.; Vitez-Sveiczer, A.; Algora, A.; Szegedi, T. N.] Inst Nucl Res ATOMKI, Bem Ter 18-c, H-4026 Debrecen, Hungary, Email: ggkiss@atomki.hu;
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 0004-637x ISBN Medium
Area Expedition Conference
Notes WOS:000850804600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5353
Permanent link to this record
 

 
Author HAWC Collaboration (Albert, A. et al); Salesa Greus, F.
Title Constraints on the Very High Energy Gamma-Ray Emission from Short GRBs with HAWC Type Journal Article
Year 2022 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.
Volume 936 Issue 2 Pages 126 - 14pp
Keywords (up)
Abstract Many gamma-ray bursts (GRBs) have been observed from radio wavelengths, and a few at very high energies (VHEs, >100 GeV). The High Altitude Water Cherenkov (HAWC) gamma-ray observatory is well suited to study transient phenomena at VHEs owing to its large field of view and duty cycle. These features allow for searches of VHE emission and can probe different model assumptions of duration and spectra. In this paper, we use data collected by HAWC between 2014 December and 2020 May to search for emission in the energy range from 80 to 800 GeV coming from a sample of 47 short GRBs that triggered the Fermi, Swift, and Konus satellites during this period. This analysis is optimized to search for delayed and extended VHE emission within the first 20 s of each burst. We find no evidence of VHE emission, either simultaneous or delayed, with respect to the prompt emission. Upper limits (90% confidence level) derived on the GRB fluence are used to constrain the synchrotron self-Compton forward-shock model. Constraints for the interstellar density as low as 10(-2) cm(-3) are obtained when assuming z = 0.3 for bursts with the highest keV fluences such as GRB 170206A and GRB 181222841. Such a low density makes observing VHE emission mainly from the fast-cooling regime challenging.
Address [Albert, A.; Dingus, B. L.; Durocher, M.; Harding, J. P.; Zhou, H.] Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA, Email: nifraija@astro.unam.mx;
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 0004-637x ISBN Medium
Area Expedition Conference
Notes WOS:000852139800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5354
Permanent link to this record