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TH Articles

უკანასკნელი დამატებები:
2023-06-28
05:47
On the Ghost Problem of Conformal Gravity / Hell, Anamaria (Munich U., ASC) ; Lust, Dieter (Munich U., ASC ; Munich, Max Planck Inst.) ; Zoupanos, George (CERN ; Heidelberg U.)
We study the metric perturbations around the de Sitter and Minkowski backgrounds in Conformal Gravity. We confirm the presence of ghosts in both cases. [...]
arXiv:2306.13714; CERN-TH-2023-116; LMU-ASC 21/23; MPP-2023-134.- 2023-08-24 - 24 p. - Published in : JHEP 2308 (2023) 168 Fulltext: 2306.13714 - PDF; document - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-06-22
06:01
The Relation Between KMOC and Worldline Formalisms for Classical Gravity / Damgaard, Poul H. (Bohr Inst. ; CERN) ; Hansen, Elias Roos (Bohr Inst.) ; Planté, Ludovic (Bohr Inst.) ; Vanhove, Pierre (IPhT, Saclay)
We demonstrate the equivalence between KMOC and worldline formalisms for classical general relativity, highlighting how the Keldysh-Schwinger in-in formalism is contained in both of them even though the KMOC representation conventionally leads to the evaluation of scattering amplitudes with Feynman propagators. The relationship between the two approaches is illustrated in detail for the momentum kick at second Post-Minkowskian order..
arXiv:2306.11454; CERN-TH-2023-096; IPhT-t23/040; LAPTH-023/23.- 2023-09-11 - 34 p. - Published in : JHEP 2309 (2023) 059 Fulltext: 2306.11454 - PDF; document - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-06-22
05:59
Charged Higgs-Boson Decays into Quarks / Chang, Jamie (PSI, Villigen) ; Kirk, Fiona (Braunschweig, Phys. Tech. Bund. ; CERN) ; Mühlleitner, Margarete (KIT, Karlsruhe, TP) ; Spira, Michael (PSI, Villigen)
We consider the full genuine next-to-leading order SUSY-QCD corrections to the charged Higgs decays into quarks supplemented by the NNLO corrections to the effective top and bottom Yukawa couplings. The NNLO corrections to the effective top Yukawa coupling are a new ingredient of our analysis. [...]
arXiv:2306.11392; KA-TP-12-2023; PSI-PR-23-18; CERN-TH-2023-112.- 2023-08-19 - 22 p. - Published in : Nucl. Phys. B 995 (2023) 116330 Fulltext: Publication - PDF; 2306.11392 - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-06-02
04:05
Composing arbitrarily many $SU(N)$ fundamentals / Polychronakos, Alexios P. (City Coll., N.Y. ; CUNY, Graduate School - U. Ctr.) ; Sfetsos, Konstantinos (Athens U. ; CERN)
We compute the multiplicity of the irreducible representations in the decomposition of the tensor product of an arbitrary number $n$ of fundamental representations of $SU(N)$, and we identify a duality in the representation content of this decomposition. Our method utilizes the mapping of the representations of $SU(N)$ to the states of free fermions on the circle, and can be viewed as a random walk on a multidimensional lattice. [...]
arXiv:2305.19345; CERN-TH-2023-085.- 2023-08-08 - 25 p. - Published in : Nucl. Phys. B 994 (2023) 116314 Fulltext: 2305.19345 - PDF; Publication - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-05-25
04:07
Dark Sectors with Mass Thresholds Face Cosmological Datasets / Allali, Itamar J. (Tufts U.) ; Rompineve, Fabrizio (CERN ; Barcelona, IFAE ; Barcelona, Autonoma U.) ; Hertzberg, Mark P. (Tufts U.)
Interacting dark sectors may undergo changes in the number of their relativistic species during the early universe, due to a mass threshold $m$ (similar to changes in the Standard Model bath), and in doing so affect the cosmic history. When such changes occur close to recombination, i.e., for $m\sim (0.1-10)~\text{eV}$, the stringent bound on the effective number of neutrino species, $N_{\text{eff}}$, can be relaxed and the value of the Hubble expansion rate $H_0$ inferred from Cosmic Microwave Background (CMB) observations raised. [...]
arXiv:2305.14166; CERN-TH-2023-084.- 2023-07-15 - 36 p. - Published in : Phys. Rev. D 108 (2023) 023527 Fulltext: PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-05-05
04:09
Precision CMB constraints on eV-scale bosons coupled to neutrinos / Sandner, Stefan (Valencia U., IFIC) ; Escudero, Miguel (CERN) ; Witte, Samuel J. (Amsterdam U. ; U. Amsterdam, GRAPPA ; ICC, Barcelona U.)
The cosmic microwave background (CMB) has proven to be an invaluable tool for studying the properties and interactions of neutrinos, providing insight not only into the sum of neutrino masses but also the free streaming nature of neutrinos prior to recombination. The CMB is a particularly powerful probe of new eV-scale bosons interacting with neutrinos, as these particles can thermalize with neutrinos via the inverse decay process, $\nu\bar{\nu} \rightarrow X$, and suppress neutrino free streaming near recombination -- even for couplings as small as $\lambda_\nu \sim \mathcal{O}(10^{-13})$. [...]
arXiv:2305.01692; IFIC/23-13; FTUV-23-0413.0599; CERN-TH-2023-073.- 2023-08-09 - 19 p. - Published in : Eur. Phys. J. C 83 (2023) 709 Fulltext: 2305.01692 - PDF; document - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-05-03
04:19
Non-singular pre-big bang scenarios from all-order $\alpha'$ correctionsNon-singular pre-big bang scenarios from all-order α′ corrections / Gasperini, M. (Bari U. ; INFN, Bari) ; Veneziano, G. (CERN ; College de France)
We reformulate in Hamiltonian language the recent proposal by Hohm and Zwiebach of an action yielding the most general $O(d,d)$-symmetric string cosmology equations, at tree-level in the string-loop expansion, but to all orders in the $\alpha'$ expansion. This allows us to give a simple characterization of a large class of non-singular, non-perturbative, pre-big bang scenarios smoothly interpolating between a low-energy initial accelerated (string frame) expansion and a phase of final (string and Einstein frame) decelerated expansion. [...]
arXiv:2305.00222; BA-TH/807-23; CERN-TH-2023-066.- 2023-07-18 - 20 p. - Published in : JHEP 2307 (2023) 144 Fulltext: document - PDF; 2305.00222 - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-05-03
04:18
The Hawking Energy in a Perturbed Friedmann-Lemaître Universe / Stock, Dennis (Geneva U., CAP ; Geneva U., Dept. Theor. Phys.) ; Di Dio, Enea (CERN) ; Durrer, Ruth (CERN)
Hawking's quasi-local energy definition quantifies the energy enclosed by a spacelike 2-sphere in terms of the amount of lightbending on the sphere caused by the energy distribution inside the sphere. This paper establishes for the first time a direct connection between the formal mathematical definition of a quasi-local energy and observations, in the context of cosmological perturbation theory. [...]
arXiv:2305.00711; CERN-TH-2023-063.- 2023-08-14 - 28 p.
Fulltext: 2305.00711 - PDF; document - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-04-29
04:01
NLO + parton-shower generator for Wc production in the POWHEG BOX RES / Ferrario Ravasio, Silvia (CERN) ; Oleari, Carlo (Milan Bicocca U. ; INFN, Milan)
We present the implementation of a next-to-leading-order plus parton-shower event generator for the hadronic production of a heavy charm quark accompanied by a leptonically-decaying $W$ boson in the POWHEG BOX RES framework. We consider both signatures, i.e. [...]
arXiv:2304.13791; CERN-TH-2023-064.- 2023-07-31 - 25 p. - Published in : Eur. Phys. J. C 83 (2023) 684 Fulltext: document - PDF; 2304.13791 - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები
2023-04-22
05:45
Neutrino Constraints and the ATOMKI X17 Anomaly / Denton, Peter B. (Brookhaven Natl. Lab.) ; Gehrlein, Julia (CERN)
Recent data from the ATOMKI group continues to confirm their claim of the existence of a new $\sim17$ MeV particle. We review and numerically analyze the data and then put into context constraints from other experiments, notably neutrino scattering experiments such as the latest reactor anti-neutrino coherent elastic neutrino nucleus scattering data and unitarity constraints from solar neutrino observations. [...]
arXiv:2304.09877; CERN-TH-2023-053.- 2023-07-01 - 11 p. - Published in : Phys. Rev. D 108 (2023) 015009 Fulltext: 2304.09877 - PDF; Publication - PDF;

დეტალური ჩანაწერი - მსგავსი ჩანაწერები