| 1. |
- Abazov, V. M., et al.
(författare)
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Odderon Exchange from Elastic Scattering Differences between pp and pp¯ Data at 1.96 TeV and from pp Forward Scattering Measurements
- 2021
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Ingår i: Physical Review Letters. - 1079-7114. ; 127:6
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Tidskriftsartikel (refereegranskat)abstract
- We describe an analysis comparing the p¯p elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections, extrapolated to a center-of-mass energy of √s=1.96 TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4σ level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in pp scattering for which the significance is between 3.4σ and 4.6σ. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound.
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| 2. |
- Addazi, Andrea, et al.
(författare)
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CDF II W-mass anomaly faces first-order electroweak phase transition
- 2023
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 83:3
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Tidskriftsartikel (refereegranskat)abstract
- We suggest an appealing strategy to probe a large class of scenarios beyond the Standard Model simultaneously explaining the recent CDF II measurement of the W boson mass and predicting first-order phase transitions (FOPT) testable in future gravitational-wave (GW) experiments. Our analysis deploys measurements from the GW channels and high energy particle colliders. We discuss this methodology focusing on the specific example provided by an extension of the Standard Model of particle physics that incorporates an additional scalar SU (2) L triplet coupled to the Higgs boson. We show that within this scenario a strong electroweak FOPT is naturally realised consistently with the measured W boson mass-shift. Potentially observable GW signatures imply the triplet mass scale to be TeV-ish, consistently with the value preferred by the W mass anomaly. This model can be tested in future space-based interferometers such as LISA, DECIGO, BBO, TianQin, TAIJI projects and in future colliders such as FCC, ILC, CEPC.
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| 3. |
- Addazi, Andrea, et al.
(författare)
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Cosmology from Strong Interactions
- 2022
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Ingår i: Universe. - : MDPI AG. - 2218-1997. ; 8:9
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Forskningsöversikt (refereegranskat)abstract
- A wealth of theoretical and phenomenological information about Quantum Chromodynamics at short and long distances collected so far in major collider measurements has profound implications in cosmology. In this review, we give a brief discussion of major implications of strongly-coupled dynamics of quarks and gluons and effects of their collective motion in physics of early Universe and in astrophysics.
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| 4. |
- Addazi, Andrea, et al.
(författare)
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Generalized Holographic Principle, Gauge Invariance and the Emergence of Gravity à la Wilczek
- 2021
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Ingår i: Frontiers in Astronomy and Space Sciences. - : Frontiers Media SA. - 2296-987X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- We show that a generalized version of the holographic principle can be derived from the Hamiltonian description of information flow within a quantum system that maintains a separable state. We then show that this generalized holographic principle entails a general principle of gauge invariance. When this is realized in an ambient Lorentzian space-time, gauge invariance under the Poincaré group is immediately achieved. We apply this pathway to retrieve the action of gravity. The latter is cast à la Wilczek through a similar formulation derived by MacDowell and Mansouri, which involves the representation theory of the Lie groups SO (Formula presented.) and SO (Formula presented.).
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| 5. |
- Addazi, Andrea, et al.
(författare)
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Gravitational echoes of lepton number symmetry breaking with light and ultralight Majorons
- 2023
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Ingår i: Journal of Cosmology and Astroparticle Physics. - 1475-7516. ; 2023:9
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Tidskriftsartikel (refereegranskat)abstract
- We formulate a version of the low-scale Majoron model equipped with an inverse seesaw mechanism featuring lepton-number preserving dimension-6 operators in the scalar potential. Contrary to its dimension-4 counterpart, we find that the model can simultaneously provide light and ultralight Majorons, neutrino masses and their mixing, while featuring strong first-order cosmological phase transitions associated to the spontaneous breaking of the lepton number and the electroweak symmetries in the early Universe. We show by a detailed numerical analysis under which circumstances the model can be probed via the primordial gravitational wave spectrum potentially observable at LISA and other planned facilities. We discuss which implications result for collider physics observables, such as scalar trilinear couplings, the scalar mixing angle and the mass of a new CP-even Higgs boson.
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| 6. |
- Addazi, Andrea, et al.
(författare)
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Gravitational footprints of massive neutrinos and lepton number breaking
- 2020
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 807
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the production of primordial Gravitational Waves (GWs) arising from First Order Phase Transitions (FOPTs) associated to neutrino mass generation in the context of type-I and inverse seesaw schemes. We examine both “high-scale” as well as “low-scale” variants, with either explicit or spontaneously broken lepton number symmetry U(1)L in the neutrino sector. In the latter case, a pseudo-Goldstone majoron-like boson may provide a candidate for cosmological dark matter. We find that schemes with softly-broken U(1)L and with single Higgs-doublet scalar sector lead to either no FOPTs or too weak FOPTs, precluding the detectability of GWs in present or near future measurements. Nevertheless, we found that, in the majoron-like seesaw scheme with spontaneously broken U(1)L at finite temperatures, one can have strong FOPTs and non-trivial primordial GW spectra which can fall well within the frequency and amplitude sensitivity of upcoming experiments, including LISA, BBO and u-DECIGO. However, GWs observability clashes with invisible Higgs decay constraints from the LHC. A simple and consistent fix is to assume the majoron-like mass to lie above the Higgs-decay kinematical threshold. We also found that the majoron-like variant of the low-scale seesaw mechanism implies a different GW spectrum than the one expected in the high-scale seesaw. This feature will be testable in future experiments. Our analysis shows that GWs can provide a new and complementary portal to test the neutrino mass generation mechanism.
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| 7. |
- Addazi, Andrea, et al.
(författare)
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QCD surprises : Strong CP problem, neutrino mass, Dark Matter and Dark Energy
- 2022
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Ingår i: Physics of the Dark Universe. - : Elsevier BV. - 2212-6864. ; 36
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Tidskriftsartikel (refereegranskat)abstract
- An unexpected explanation for neutrino mass, Dark Matter (DM) and Dark Energy (DE) from genuine Quantum Chromodynamics (QCD) of the Standard Model (SM) is proposed here, while the strong CP problem is resolved without any need to account for fundamental axions. We suggest that the neutrino sector can be in a double phase in the Universe: i) relativistic neutrinos, belonging to the SM; ii) non-relativistic condensate of Majorana neutrinos. The condensate of neutrinos can provide an attractive alternative candidate for the DM, being in a cold coherent state. We will explain how neutrinos, combining into Cooper pairs, can form collective low-energy degrees of freedom, hence providing a strongly motivated candidate for the QCD (composite) axion.
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| 8. |
- Aranda, Alfredo, et al.
(författare)
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Gauge Couplings Evolution from the Standard Model, through Pati–Salam Theory, into E8 Unification of Families and Forces
- 2023
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Ingår i: Universe. - : MDPI AG. - 2218-1997. ; 9:2
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Tidskriftsartikel (refereegranskat)abstract
- We explore the potential of ultimate unification of the Standard Model matter and gauge sectors into a single (Formula presented.) superfield in ten dimensions via an intermediate Pati–Salam gauge theory. Through a consistent realisation of a (Formula presented.) orbifolding procedure and renormalisation group evolution of gauge couplings, we establish several novel benchmark scenarios for New Physics that are worth further phenomenological exploration.
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| 9. |
- Aranda, Alfredo, et al.
(författare)
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Sculpting the Standard Model from low-scale gauge-Higgs-matter E8 grand unification in ten dimensions
- 2023
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Ingår i: Nuclear Physics B. - 0550-3213. ; 993
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Tidskriftsartikel (refereegranskat)abstract
- The construction and general implications of a model with complete supersymmetric unification of the Standard Model matter content, interactions and families' replication into a single E8 gauge superfield in ten dimensions is presented. The gauge and extended Poincaré symmetries are broken through compactification of the T6/(Z3×Z3) orbifold with Wilson lines, which reduces the original symmetry and matter content into those of the Standard Model plus additional heavier states. Proton decay can be suppressed automatically while the compactification scale may be as low as 109GeV, so that the corresponding GUT-scale physics may be potentially accessible and testable by future collider measurements.
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| 10. |
- Babiarz, Izabela, et al.
(författare)
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Central exclusive production of scalar and pseudoscalar charmonia in the light-front kT -factorization approach
- 2020
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Ingår i: Physical Review D. - 2470-0010. ; 102:11
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Tidskriftsartikel (refereegranskat)abstract
- We study exclusive production of scalar χc0χc(0++) and pseudoscalar ηc charmonia states in proton-proton collisions at the LHC energies. The amplitudes for gg→χc0 as well as for gg→ηc mechanisms are derived in the kT-factorization approach. The pp→ppηc reaction is discussed for the first time. We have calculated rapidity, transverse momentum distributions, and such correlation observables as the distribution in relative azimuthal angle and (t1,t2) distributions. The latter two observables are very different for χc0 and ηc cases. In contrast to the inclusive production of these mesons considered very recently in the literature, in the exclusive case, the cross section for ηc is much lower than that for χc0, which is due to a special interplay of the corresponding vertices and off-diagonal unintegrated gluon distributions used to calculate the cross sections. We present the numerical results for the key observables in the framework of potential models for the light-front quarkonia wave functions. We also discuss how different the absorptive corrections are for both considered cases.
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