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Related papers: Light Scalars and the KOTO Anomaly

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Medium-energy electron beam-dump experiments provide an intense sources of secondary muons. These particles can be used to search for muon-coupling light dark scalars that may explain the $(g-2)_\mu$ anomaly. We applied this idea to SLAC…

High Energy Physics - Experiment · Physics 2018-12-26 L. Marsicano , M. Battaglieri , A. Celentano , R. De Vita , Yi-Ming Zhong

While the main goal of the J-PARC KOTO experiment is to measure the rare decay $K_L \to \pi^0 \nu \bar \nu$, the unique setup of KOTO raises the possibility to search for physics beyond the Standard Model, in an attempt to probe parts of…

High Energy Physics - Phenomenology · Physics 2023-09-28 Yoav Afik , Babette Döbrich , Jan Jerhot , Yotam Soreq , Kohsaku Tobioka

Recent measurements of the proton radius using the Lamb shift in muonic hydrogen are troublingly discrepant with values extracted from hydrogen spectroscopy and electron-proton scattering experiments. This discrepancy, which differs by more…

High Energy Physics - Phenomenology · Physics 2017-08-08 Yu-Sheng Liu

The MiniBooNE experiment has recently reported an anomalous 4.5$\sigma$ excess of electron-like events consistent with $\nu_e$ appearance from a $\nu_\mu$ beam at short-baseline. Given the lack of corresponding $\nu_\mu$ disappearance…

High Energy Physics - Phenomenology · Physics 2019-08-08 Johnathon R. Jordan , Yonatan Kahn , Gordan Krnjaic , Matthew Moschella , Joshua Spitz

We explore the possible exotic particle content beyond the standard model by examining all its scalar bilinear combinations. We categorize these exotic scalar fields and show that without the suppression of (A) their Yukawa couplings with…

High Energy Physics - Phenomenology · Physics 2011-09-13 Ernest Ma , Martti Raidal , Utpal Sarkar

We argue that demanding a consistent cosmological history, including the absence of domain walls and strongly interacting relics at the Peccei-Quinn scale, singles out two concrete realizations of hadronic QCD axions as viable dark matter…

High Energy Physics - Phenomenology · Physics 2023-10-27 Gonzalo Alonso-Álvarez , James M. Cline , Tianzhuo Xiao

In this work we study possible connections between $B$-meson anomalies and Kaon physics observables in the context of combined solutions with the singlet and triplet scalar leptoquarks $S_1$ and $S_3$. By assuming a flavor structure for the…

High Energy Physics - Phenomenology · Physics 2022-04-27 David Marzocca , Sokratis Trifinopoulos , Elena Venturini

The excess of solar-neutrino events above 13 MeV that has been recently observed by Superkamiokande can be explained by vacuum oscillations (VO). If the boron neutrino flux is 20% smaller than the standard solar model (SSM) prediction and…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. Berezinsky , G. Fiorentini , M. Lissia

The rare kaon decays K_L -> pi^0 nu {bar nu}, K^+ -> pi^+ nu {bar nu}, K_L -> pi^0 e^+ e^- and K_L -> pi^0 mu^+ mu^- are theoretically very clean and, being strongly CKM suppressed, highly sensitive to New Physics (NP). Recent Flavour…

High Energy Physics - Phenomenology · Physics 2008-11-26 Cecilia Tarantino

One of the portals to new physics is a light scalar coupled to the Standard Model (SM) Higgs. In this paper we focus on hadronic decays of such a scalar in the regime where QCD dynamics is nonperturbative, resulting, e.g., in decays to…

High Energy Physics - Phenomenology · Physics 2024-07-19 Patrick J. Blackstone , Jaume Tarrús Castellà , Emilie Passemar , Jure Zupan

There is no doubt that in the coming years we will witness the renaissance of kaon flavour physics with crucial measurements of the branching ratios for the rare decays $K^+\rightarrow\pi^+\nu\bar\nu$ and $K_{L}\rightarrow\pi^0\nu\bar\nu$…

High Energy Physics - Phenomenology · Physics 2016-07-18 Andrzej J. Buras

During the last fifteen years B_{s,d} decays, B_{s,d}^0-\bar B^0_{s,d} mixings, CP-violating asymmetries S_{\psi K_S} and S_{\psi\phi} provided the dominant information about the pattern of flavour violation within the SM and its…

High Energy Physics - Phenomenology · Physics 2015-10-02 Andrzej J. Buras

The KOTO ($K^0$ at Tokai) experiment aims to observe the CP-violating rare decay $K_L \rightarrow \pi^0 \nu \bar{\nu}$ by using a long-lived neutral-kaon beam produced by the 30 GeV proton beam at the Japan Proton Accelerator Research…

The confirmation of the Higgs boson in Run I data at the Large Hadron Collider (LHC) and the excesses in recent Run II data suggest scenarios beyond the Standard Model (SM). We pursue a study in a minimal model which is an extension of a…

We explore the possibility that the interactions of a light scalar singlet, which mixes with the Standard Model~(SM) Higgs, also receive other UV contributions of comparable size. We focus, in particular, on the flavor aligned limit, where…

High Energy Physics - Phenomenology · Physics 2025-11-10 Cédric Delaunay , Teppei Kitahara , Yotam Soreq , Jure Zupan

Based on a number of features from proton-proton collisions taken during Run 1 data taking period at the LHC, a boson with a mass around the Electro-Weak scale was postulated such that a significant fraction of its decays would comprise the…

High Energy Physics - Phenomenology · Physics 2019-09-11 Stefan von Buddenbrock , Bruce Mellado

Rare kaon decays provide sensitive tests of new physics. In this work, we focus on scalar and pseudoscalar operators, analysing the $K\to \pi \ell^+\ell^-$ and $K\to \ell^+\ell^-$ decays. We highlight the complementary role of different…

High Energy Physics - Phenomenology · Physics 2025-12-19 G. D'Ambrosio , A. M. Iyer , F. Mahmoudi , S. Neshatpour

An excess of low-energy electronic recoil events over known backgrounds was recently observed in the XENON1T detector, where $285$ events are observed compared to an expected $232 \pm 15$ events from the background-only fit to the data in…

High Energy Physics - Phenomenology · Physics 2021-03-03 Athanasios Karozas , Stephen F. King , George K. Leontaris , Dimitrios K. Papoulias

The precision expected for the rare $K\to \pi \nu\bar\nu$ decays by the NA62 and KOTO experiments in the coming decade will rival their current SM predictions. In preparation for this upcoming opportunity, we review the SM predictions and…

High Energy Physics - Phenomenology · Physics 2015-06-02 Robert Knegjens

We consider implications of the diphoton excess recently observed at the LHC on the anomalous magnetic dipole moment of the muon $(g-2)_\mu = 2 a_\mu$, hypothesizing that the possible 750 GeV resonance is a (pseudo)scalar particle. The…

High Energy Physics - Phenomenology · Physics 2016-05-20 Seungwon Baek , Jae-hyeon Park