English
Related papers

Related papers: Realistic model for a fifth force explaining anoma…

200 papers

A recent update from MiniBooNE has strengthened the observed $4.8\sigma$ excess of $e$-like events. Motivated by this and other notable deviations from standard model predictions, such as the muon $(g-2)$, we propose a solution to low…

High Energy Physics - Phenomenology · Physics 2021-08-03 Asli Abdullahi , Matheus Hostert , Silvia Pascoli

We consider several extensions of the Standard Model (SM) which can explain the anomalies observed by the Atomki collaboration in the decay of excited states of Beryllium via a new boson with a mass around 17 MeV yielding $e^+e^-$ pairs. We…

High Energy Physics - Phenomenology · Physics 2019-05-21 Luigi Delle Rose , Shaaban Khalil , Simon J. D. King , Stefano Moretti

We consider the possibility of observing deviations from the Standard Model gauge-boson self-couplings at future $e\gamma$ colliders. We concentrate on the process $e^-\gamma \rightarrow \nu W^- Z$, which is particularly sensitive to the…

High Energy Physics - Phenomenology · Physics 2009-12-30 K. Cheung , S. Dawson , T. Han , G. Valencia

In the absence of any new physics signals at the Large Hadron Collider (LHC), anomalous results at low energy experiments have become the subject of increased attention. We focus on three such results from the LSND, MiniBooNE (MB), and…

High Energy Physics - Phenomenology · Physics 2024-10-29 Waleed Abdallah , Raj Gandhi , Tathagata Ghosh , Najimuddin Khan , Samiran Roy , Subhojit Roy

The possible origin of an $X$-boson having a mass value around $17 \, \mbox{MeV}$ had motivated us to investigate its interaction with leptons of QED. This new hypothetical particle can possibly be a candidate to describe the so called…

High Energy Physics - Phenomenology · Physics 2018-02-08 Mario J. Neves , Everton M. C. Abreu

A series of experiments studying neutrinos from intense radioactive sources have reported a deficit in the measured event rate which, in combination, has reached a statistical significance of $\sim 5\sigma$. In this paper, we explore…

High Energy Physics - Phenomenology · Physics 2023-06-02 Vedran Brdar , Julia Gehrlein , Joachim Kopp

The recent updated angular analysis of the $B\to K^*\mu^+\mu^-$ decay by the LHCb collaboration is interpreted by performing a global fit to all relevant measurements probing the flavour-changing neutral current $b\to s\mu^+\mu^-$…

High Energy Physics - Phenomenology · Physics 2015-03-24 Wolfgang Altmannshofer , David M. Straub

The standard electroweak interaction is here re-assessed to accommodate two different situations in Particle Physics. The first one is a $Z'$-model at the TeV-scale physics. The second one tackles the recent discussion of a possible fifth…

High Energy Physics - Phenomenology · Physics 2017-11-16 M. J. Neves , J. A. Helaÿel-Neto

The 4.2$\sigma$ discrepancy between the standard model prediction for the muon anomalous magnetic moment $a_\mu$ and the experimental result is accompanied by other anomalies. A crucial input for the prediction is the hadronic vacuum…

High Energy Physics - Phenomenology · Physics 2022-07-06 Luc Darmé , Giovanni Grilli di Cortona , Enrico Nardi

The angular distribution of the flavor-changing neutral current decay B$^+$ $\to$ K$^+\mu^+\mu^-$ is studied in proton-proton collisions at a center-of-mass energy of 8 TeV. The analysis is based on data collected with the CMS detector at…

High Energy Physics - Experiment · Physics 2018-12-26 CMS Collaboration

Recent experimental results in $B$ physics from Belle, BaBar and LHCb suggest new physics (NP) in the weak $b\to c$ charged-current and the $b\to s$ neutral-current processes. Here we focus on the charged-current case and specifically on…

High Energy Physics - Phenomenology · Physics 2022-10-10 Bhubanjyoti Bhattacharya , Thomas Browder , Quinn Campagna , Alakabha Datta , Shawn Dubey , Lopamudra Mukherjee , Alexei Sibidanov

The low lying states in $^8$Be are believed to have a two-alpha cluster structure and hence a large intrinsic quadrupole deformation. An earlier calculation showed a large collective enhancement in gamma transition probability between the…

Nuclear Experiment · Physics 2009-11-10 V. M. Datar , Suresh Kumar , D. R. Chakrabarty , V. Nanal , E. T. Mirgule , A. Mitra , H. H. Oza

To address the long-standing $(g-2)_{\mu}$ anomaly via a light boson, in Ref. [1] we proposed to extend the standard model (SM) by the local $(B-L)_{23}$, under which only the second and third generations of fermions are charged. It…

High Energy Physics - Phenomenology · Physics 2021-04-30 Zhaofeng Kang , Yoshihiro Shigekami

In this proceedings, we discuss a light (17 MeV) $Z'$ solution to the anomaly observed in the decay of Beryllium-8 by the Atomki collaboration. We detail an anomaly free model with minimal particle content which can satisfy all other…

High Energy Physics - Phenomenology · Physics 2019-05-14 Luigi Delle Rose , Shaaban Khalil , Simon J. D. King , Stefano Moretti , Ahmed M. Thabt

Experimental searches for new, "fifth" forces are attracting a lot of attention because they allow to test theoretical extensions to the standard model. Here, we report a new experimental search for possible fifth forces, specifically…

Atomic Physics · Physics 2022-12-13 Kai Wei , Wei Ji , Changbo Fu , Arne Wickenbrock , Jiancheng Fang , Victor Flambaum , Dmitry Budker

A discrepancy between the measured anomalous magnetic moment of the muon $(g - 2)_{\mu}$ and computed Standard Model value now stands at a combined $4.2\sigma$ following experiments at Brookhaven National Lab (BNL) and the Fermi National…

High Energy Physics - Phenomenology · Physics 2021-11-17 Joseph L. Lamborn , Tianjun Li , James A. Maxin , Dimitri V. Nanopoulos

Recent reactor neutrino experiments observe an anomalous excess around 5 MeV in the prompt energy spectra of positrons following the inverse beta decay reaction. In this note we suggest that this 5 MeV anomaly was already present in a much…

High Energy Physics - Experiment · Physics 2018-07-10 V. Zacek , G. Zacek , P. Vogel , J. -L. Vuilleumier

We discuss the current status of the anomaly in beryllium-8 nuclear transitions recently reported in the angular distribution of internal conversion electron-positron pairs. We present a phenomenological analysis of the signal and review…

High Energy Physics - Phenomenology · Physics 2017-08-28 Bartosz Fornal

We investigate how far a new physics scenario affecting primarily the third generation fermions can ameliorate the tension between B-decay observables and Standard Model expectations. Adopting a model-independent approach, we find that…

High Energy Physics - Phenomenology · Physics 2013-01-07 Debajyoti Choudhury , Dilip Kumar Ghosh , Anirban Kundu

We review the current status and implications of the anomalies (i.e. deviations from the Standard Model predictions) in semi-leptonic $B$ meson decays, both in the charged and in the neutral current. In $b\to s\ell^+\ell^-$ transitions…

High Energy Physics - Phenomenology · Physics 2023-12-25 Bernat Capdevila , Andreas Crivellin , Joaquim Matias