| |
Records |
Links |
|
Author |
Maluf, R.V.; Olmo, G.J. |
|
| |
Title  |
Vacuum polarization and induced Maxwell and Kalb-Ramond effective action in very special relativity |
Type |
Journal Article |
| |
Year |
2023 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
| |
Volume |
108 |
Issue |
9 |
Pages |
095022 - 13pp |
|
| |
Keywords |
|
|
| |
Abstract |
This work investigates the implications of very special relativity (VSR) on the calculation of vacuum polarization for fermions in the presence of Maxwell and Kalb-Ramond gauge fields in four-dimensional spacetime. We derive the SIM(2)-covariant gauge theory associated with an Abelian antisymmetric twotensor and its corresponding field strength. We demonstrate that the free VSR-Kalb-Ramond electrodynamics is equivalent to a massive scalar field with a single polarization. Furthermore, we determine an explicit expression for the effective action involving Maxwell and Kalb-Ramond fields due to fermionic vacuum polarization at one-loop order. The quantum corrections generate divergences free of nonlocal terms only in the VSR-Maxwell sector. At the same time, we observe UV/IR mixing divergences due to the entanglement of VSR-nonlocal effects with quantum higher-derivative terms for the Kalb-Ramond field. However, in the lower energy limit, the effective action can be renormalized like in the Lorentz invariant case. |
|
| |
Address |
[Maluf, Roberto, V; Olmo, Gonzalo J.] Univ Fed Ceara UFC, Dept Fis, Campus Pici,CP 6030, BR-60455760 Fortaleza, CE, Brazil, Email: r.v.maluf@fisica.ufc.br; |
|
| |
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:001111823400003 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
5863 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Nebot, M.; Botella, F.J.; Branco, G.C. |
|
| |
Title |
Vacuum induced CP violation generating a complex CKM matrix with controlled scalar FCNC |
Type |
Journal Article |
| |
Year |
2019 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
|
| |
Volume |
79 |
Issue |
8 |
Pages |
711 - 23pp |
|
| |
Keywords |
|
|
| |
Abstract |
We propose. a viable minimal model with spontaneous CP violation in the framework of a two Higgs doublet model. The model is based on a generalised Branco-Grimus-Lavoura model with a flavoured Z(2) symmetry, under which two of the quark families are even and the third one is odd. The lagrangian respects CP invariance, but the vacuum has a CP violating phase, which is able to generate a complex CKM matrix, with the rephasing invariant strength of CP violation compatible with experiment. The question of scalar mediated flavour changing neutral couplings is carefully studied. In particular we point out a deep connection between the generation of a complex CKM matrix from a vacuum phase and the appearance of scalar FCNC. The scalar sector is presented in detail, showing that the new scalars are necessarily lighter than 1 TeV. A complete analysis of the model including the most relevant constraints is performed, showing that it is viable and that it has definite implications for the observation of New Physics signals in, for example, flavour changing Higgs decays or the discovery of the new scalars at the LHC. We give special emphasis to processes like t -> hc, hu, as well as h -> bs, bd, which are relevant for the LHC and the ILC. |
|
| |
Address |
[Nebot, Miguel; Branco, Gustavo C.] UL, Dept Fis, Inst Super Tecn, Av Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: miguel.r.nebot.gomez@tecnico.ulisboa.pt; |
|
| |
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:000483225300003 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
4130 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Khosa, C.K.; Sanz, V.; Soughton, M. |
|
| |
Title |
Using machine learning to disentangle LHC signatures of Dark Matter candidates |
Type |
Journal Article |
| |
Year |
2021 |
Publication |
Scipost Physics |
Abbreviated Journal |
SciPost Phys. |
|
| |
Volume |
10 |
Issue |
6 |
Pages |
151 - 26pp |
|
| |
Keywords |
|
|
| |
Abstract |
We study the prospects of characterising Dark Matter at colliders using Machine Learning (ML) techniques. We focus on the monojet and missing transverse energy (MET) channel and propose a set of benchmark models for the study: a typical WIMP Dark Matter candidate in the form of a SUSY neutralino, a pseudo-Goldstone impostor in the shape of an Axion-Like Particle, and a light Dark Matter impostor whose interactions are mediated by a heavy particle. All these benchmarks are tensioned against each other, and against the main SM background (Z+jets). Our analysis uses both the leading-order kinematic features as well as the information of an additional hard jet. We explore different representations of the data, from a simple event data sample with values of kinematic variables fed into a Logistic Regression algorithm or a Fully Connected Neural Network, to a transformation of the data into images related to probability distributions, fed to Deep and Convolutional Neural Networks. We also study the robustness of our method against including detector effects, dropping kinematic variables, or changing the number of events per image. In the case of signals with more combinatorial possibilities (events with more than one hard jet), the most crucial data features are selected by performing a Principal Component Analysis. We compare the performance of all these methods, and find that using the 2D images of the combined information of multiple events significantly improves the discrimination performance. |
|
| |
Address |
[Khosa, Charanjit Kaur; Sanz, Veronica; Soughton, Michael] Univ Sussex, Dept Phys & Astron, Brighton BN1 9QH, E Sussex, England, Email: Charanjit.Kaur@sussex.ac.uk; |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Scipost Foundation |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2542-4653 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000680038800002 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
4927 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Liang, W.H.; Ikeno, N.; Oset, E. |
|
| |
Title |
Upsilon(nl) decay into B(*) (B)over-bar(*) |
Type |
Journal Article |
| |
Year |
2020 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
|
| |
Volume |
803 |
Issue |
|
Pages |
135340 - 6pp |
|
| |
Keywords |
|
|
| |
Abstract |
We have evaluated the decay modes of the Upsilon(4s), Upsilon(3d), Upsilon(5s), Upsilon(6s) states into B (B) over bar, B (B) over bar* + c.c., B* (B) over bar*, B-s(B) over bar (s), B-s(B) over bar (s)* + c.c., B-s* (B) over bar (s)* using the P-3(0) model to hadronize the bb vector seed, fitting some parameters to the data. We observe that the Upsilon(4s) state has an abnormally large amount of mesonmeson components in the wave function, while the other states are largely b (b) over bar. We predict branching ratios for the different decay channels which can be contrasted with experiment for the case of the Upsilon(5s) state. While globally the agreement is fair, we call the attention to some disagreement that could be a warning for the existence of more elaborate components in the state. |
|
| |
Address |
[Liang, Wei-Hong; Oset, Eulogio] Guangxi Normal Univ, Dept Phys, Guilin 541004, Peoples R China, Email: liangwh@gxnu.edu.cn; |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0370-2693 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000521730300046 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
4355 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
T2K Collaboration (Abe, K. et al); Antonova, M.; Cervera-Villanueva, A.; Molina Bueno, L.; Novella, P. |
|
| |
Title |
Updated T2K measurements of muon neutrino and antineutrino disappearance using 3.6 x 10^21 protons on target |
Type |
Journal Article |
| |
Year |
2023 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
| |
Volume |
108 |
Issue |
7 |
Pages |
072011 - 10pp |
|
| |
Keywords |
|
|
| |
Abstract |
Muon neutrino and antineutrino disappearance probabilities are identical in the standard three-flavor neutrino oscillation framework, but CPT violation and nonstandard interactions can violate this symmetry. In this work we report the measurements of sin2 theta 23 and Delta m232 independently for neutrinos and antineutrinos. The aforementioned symmetry violation would manifest as an inconsistency in the neutrino and antineutrino oscillation parameters. The analysis discussed here uses a total of 1.97 x 1021 and 1.63 x 1021 protons on target taken with a neutrino and antineutrino beam respectively, and benefits from improved flux and cross section models, new near-detector samples and more than double the data reducing the overall uncertainty of the result. No significant deviation is observed, consistent with the standard neutrino oscillation picture. |
|
| |
Address |
[Labarga, L.; Ospina, N.] Univ Autonoma Madrid, Dept Theoret Phys, Madrid 28049, 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:001102916000001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
5846 |
|
| Permanent link to this record |
