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Author Bandyopadhyay, P.; Karan, A.; Mandal, R.; Parashar, S.
Title Distinguishing signatures of scalar leptoquarks at hadron and muon colliders Type Journal Article
Year 2022 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 82 Issue 10 Pages 916 - 41pp
Keywords
Abstract (down) While the hunt for new states beyond the standardmodel (SM) goes on for various well motivated theories, the leptoquarks are among the most appealing scenarios at recent times due to a series of tensions observed in B-meson decays. We consider SU(2) singlet and triplet scalar leptoquarks separately, which contribute to charged and neutral current B-meson decays. Focusing on the single production of these two scalar leptoquarks, we perform a PYTHIA-based simulation considering all the dominant SM backgrounds at the current and future setups of the Large Hadron Collider (LHC). The mono-b-jet + p(T) finalstate gives the strongest signal for the singlet leptoquark at the 30 TeV LHC or Future Circular Collider (FCC), with a possibility of 5 sigma signal significance with greater than or similar to 1000 fb(-1) of integrated luminosity, for the chosen benchmark scenarios. The finalstate consisting of a c-jet and two tau-jets provides highest reach for the singlet leptoquark, probing an O(10(-1)) value of the Yukawa-type couplings for up to 3.0 TeV leptoquark mass. For the triplet leptoquark, 1 – jet + 2 μ+ p(T) topology is the most optimistic signature at the LHC, probing leptoquark couplings to fermions at O(10(-1)) value for the leptoquark mass range up to 4.0 TeV. The invariant mass edge distribution is found to be instrumental in determination of the leptoquarkmass scale at the LHC. We also perform the analysis at the proposed multiTeV muon collider, where an O(10(-1)) leptoquark Yukawa coupling can be probed for a 5.0 TeV leptoquark mass.
Address [Bandyopadhyay, Priyotosh; Karan, Anirban; Parashar, Snehashis] Indian Inst Technol Hyderabad, Sangareddy 502284, Telangana, India, Email: bpriyo@phy.iith.ac.in;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000868388600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5391
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Author Utrilla Gines, E.; Mena, O.; Witte, S.J.
Title Revisiting constraints on WIMPs around primordial black holes Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 106 Issue 6 Pages 063538 - 14pp
Keywords
Abstract (down) While primordial black holes (PBHs) with masses MPBH greater than or similar to 10-11 Mo cannot comprise the entirety of dark matter, the existence of even a small population of these objects can have profound astrophysical consequences. A subdominant population of PBHs will efficiently accrete dark matter particles before matter-radiation equality, giving rise to high-density dark matter spikes. We consider here the scenario in which dark matter is comprised primarily of weakly interacting massive particles (WIMPs) with a small subdominant contribution coming from PBHs, and revisit the constraints on the annihilation of WIMPs in these spikes using observations of the isotropic gamma-ray background (IGRB) and the cosmic microwave background (CMB), for a range of WIMP masses, annihilation channels, cross sections, and PBH mass functions. We find that the constraints derived using the IGRB have been significantly overestimated (in some cases by many orders of magnitude), and that limits obtained using observations of the CMB are typically stronger than, or comparable to, those coming from the IGRB. Importantly, we show that similar to OoMo thorn PBHs can still contribute significantly to the dark matter density for sufficiently low WIMP masses and p-wave annihilation cross sections.
Address [Utrilla Gines, Estanis; Mena, Olga] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Parc Cient UV,C Catedrat Jose Beltran 2, E-46980 Paterna, Spain
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:000866519600007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5390
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Author Wilson, J.N. et al; Algora, A.
Title Angular momentum generation in nuclear fission Type Journal Article
Year 2021 Publication Nature Abbreviated Journal Nature
Volume 590 Issue 7847 Pages 566-570
Keywords
Abstract (down) When a heavy atomic nucleus splits (fission), the resulting fragments are observed to emerge spinning(1); this phenomenon has been a mystery in nuclear physics for over 40 years(2,3). The internal generation of typically six or seven units of angular momentum in each fragment is particularly puzzling for systems that start with zero, or almost zero, spin. There are currently no experimental observations that enable decisive discrimination between the many competing theories for the mechanism that generates the angular momentum(4-12). Nevertheless, the consensus is that excitation of collective vibrational modes generates the intrinsic spin before the nucleus splits (pre-scission). Here we show that there is no significant correlation between the spins of the fragment partners, which leads us to conclude that angular momentum in fission is actually generated after the nucleus splits (post-scission). We present comprehensive data showing that the average spin is strongly mass-dependent, varying in saw-tooth distributions. We observe no notable dependence of fragment spin on the mass or charge of the partner nucleus, confirming the uncorrelated post-scission nature of the spin mechanism. To explain these observations, we propose that the collective motion of nucleons in the ruptured neck of the fissioning system generates two independent torques, analogous to the snapping of an elastic band. A parameterization based on occupation of angular momentum states according to statistical theory describes the full range of experimental data well. This insight into the role of spin in nuclear fission is not only important for the fundamental understanding and theoretical description of fission, but also has consequences for the gamma-ray heating problem in nuclear reactors(13,14), for the study of the structure of neutron-rich isotopes(15,16), and for the synthesis and stability of super-heavy elements(17,18). gamma-ray spectroscopy experiments on the origin of spin in the products of nuclear fission of spin-zero nuclei suggest that the fission fragments acquire their spin after scission, rather than before.
Address [Wilson, J. N.; Thisse, D.; Lebois, M.; Jovancevic, N.; Adsley, P.; Babo, M.; Chakma, R.; Delafosse, C.; Haefner, G.; Hauschild, K.; Ibrahim, F.; Ljungvall, J.; Lopez-Martens, A.; Lozeva, R.; Matea, I; Nemer, J.; Popovitch, Y.; Qi, L.; Tocabens, G.; Verney, D.] Univ Paris Saclay, IJC Lab, CNRS, IN2P3, Orsay, France, Email: jonathan.wilson@ijclab.in2p3.fr
Corporate Author Thesis
Publisher Nature Research Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-0836 ISBN Medium
Area Expedition Conference
Notes WOS:000621583600006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4717
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Author Yao, D.L.; Alvarez-Ruso, L.; Hiller Blin, A.N.; Vicente Vacas, M.J.
Title Weak pion production off the nucleon in covariant chiral perturbation theory Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 7 Pages 076004 - 25pp
Keywords
Abstract (down) Weak pion production off the nucleon at low energies has been systematically investigated in manifestly relativistic baryon chiral perturbation theory with explicit inclusion of the Delta(1232) resonance. Most of the involved low-energy constants have been previously determined in other processes such as pion-nucleon elastic scattering and electromagnetic pion production off the nucleon. For numerical estimates, the few remaining constants are set to be of natural size. As a result, the total cross sections for single pion production on neutrons and protons, induced either by neutrino or antineutrino, are predicted. Our results are consistent with the scarce existing experimental data except in the nu(mu)n -> mu(-)n pi(+) channel, where higher-order contributions might still be significant. The Delta resonance mechanisms lead to sizeable contributions in all channels, especially in nu(mu)p -> mu(-) p pi(+), even though the considered energies are close to the production threshold. The present study provides a well-founded low-energy benchmark for phenomenological models aimed at the description of weak pion production processes in the broad kinematic range of interest for current and future neutrino-oscillation experiments.
Address [Yao, De-Liang; Alvarez-Ruso, Luis; Vicente Vacas, M. J.] UV, CSIC, Dept Fis Teor, Ctr Mixto,Inst Invest Paterna, E-46071 Valencia, Spain, Email: Deliang.Yao@ific.uv.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:000446557200006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3752
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Author Olmo, G.J.; Rubiera-Garcia, D.
Title Junction conditions in Palatini f(R) gravity Type Journal Article
Year 2020 Publication Classical and Quantum Gravity Abbreviated Journal Class. Quantum Gravity
Volume 37 Issue 21 Pages 215002 - 11pp
Keywords f(R) gravity; junction conditions; Palatini approach; stellar structure
Abstract (down) We work out the junction conditions for f(R) gravity formulated in metric-affine (Palatini) spaces using a tensor distributional approach. These conditions are needed for building consistent models of gravitating bodies with an interior and exterior regions matched at some hypersurface. Some of these conditions depart from the standard Darmois-Israel ones of general relativity and from their metric f(R) counterparts. In particular, we find that the trace of the stress-energy momentum tensor in the bulk must be continuous across the matching hypersurface, though its normal derivative need not to. We illustrate the relevance of these conditions by considering the properties of stellar surfaces in polytropic models, showing that the range of equations of state with potentially pathological effects is shifted beyond the domain of physical interest. This confirms, in particular, that neutron stars and white dwarfs can be safely modelled within the Palatini f(R) framework.
Address [Olmo, Gonzalo J.] Univ Valencia, Ctr Mixto Univ Valencia, CSIC, Dept Fis Teor, Valencia 46100, Spain, Email: gonzalo.olmo@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 0264-9381 ISBN Medium
Area Expedition Conference
Notes WOS:000575326000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4555
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