The simplest extension of the SM to account for the observed neutrino masses and mixings is the addition of at least two singlet fermions (or right-handed neutrinos). If their masses lie at or below the GeV scale, such new fermions would be produced in meson decays. Similarly, provided they are sufficiently heavy, their decay channels may involve mesons in the final state. Although the couplings between mesons and heavy neutrinos have been computed previously, significant discrepancies can be found in the literature. The aim of this paper is to clarify such discrepancies and provide consistent expressions for all relevant effective operators involving mesons with masses up to 2 GeV. Moreover, the effective Lagrangians obtained for both the Dirac and Majorana scenarios are made publicly available as FeynRules models so that fully differential event distributions can be easily simulated. As an application of our setup, we numerically compute the expected sensitivity of the DUNE near detector to these heavy neutral leptons.
We propose to use the unique event topology and reconstruction capabilities of liquid argon time projection chambers to study sub-GeV atmospheric neutrinos. The detection of low energy recoiled protons in DUNE allows for a determination of the leptonic $CP$-violating phase independent from the accelerator neutrino measurement. Our findings indicate that this analysis can exclude several values of $δ_{CP}$ beyond the $3σ$ level. Moreover, the determination of the sub-GeV atmospheric neutrino flux will have important consequences in the detection of diffuse supernova neutrinos and in dark matter…
We study how nonstandard neutrino interactions (NSI) may be probed by a combination of coherent elastic neutrino-nucleus scattering, neutrino oscillation and collider data, from COHERENT, DUNE, T2HK and the high-luminosity (HL) LHC. We focus on NSI induced by a new flavored gauge boson $Z'$ in a generic anomaly-free ultraviolet-complete model. For $Z'$ masses above 10 GeV, the HL-LHC has the best sensitivity regardless of the flavor structure of the model. For masses between 0.01 GeV-10 GeV, current LHCb data and future COHERENT data have the best sensitivity unless the $Z'$ couplings to the f…
We explore the sensitivity of the Deep Underground Neutrino Experiment (DUNE) near detector and the proposed DUNE-PRISM movable near detector to sub-GeV dark matter, specifically scalar dark matter coupled to the Standard Model via a sub-GeV dark photon. We consider dark matter produced in the DUNE target that travels to the detector and scatters off electrons. By combining searches for dark matter at many off-axis positions with DUNE-PRISM, sensitivity to this scenario can be much stronger than when performing a measurement at one on-axis position.
The simplest extension of the SM to account for the observed neutrino masses and mixings is the addition of at least two singlet fermions (or right-handed neutrinos). If their masses lie at or below the GeV scale, such new fermions would be produced in meson decays. Similarly, provided they are sufficiently heavy, their decay channels may involve mesons in the final state. In this work, we provide consistent expressions for the relevant effective operators involving neutrinos and mesons with masses up to 2 GeV. The associated effective Lagrangian has been implemented in FeynRules, allowing for…
In this work we analyze quantum decoherence in neutrino oscillations considering the Open Quantum System framework and oscillations through matter for three neutrino families. Taking DUNE as a case study we performed sensitivity analyses for two neutrino flux configurations finding limits for the decoherence parameters. We also offer a physical interpretation for a new peak which arises at the $ν_{e}$ appearance probability with decoherence. The best sensitivity regions found for the decoherence parameters are $Γ_{21}\le 1.2\times10^{-23}\,\text{GeV}$ and $Γ_{32}\le 7.7\times10^{-25}\,\text{Ge…
While the QCD axion is often considered to be necessarily light ($\lesssim$ eV), recent work has opened a viable and interesting parameter space for heavy axions, which solve both the Strong CP and the axion Quality Problems. These well-motivated heavy axions, as well as the generic axion-like-particles, call for explorations in the GeV mass realm at collider and beam dump environments. The primary upcoming neutrino experiment, Deep Underground Neutrino Experiment (DUNE), is simultaneously also a powerful beam dump experiment, enabled by its multipurpose Near Detector (ND) complex. In this stu…
DUNE with its cutting edge technology is designed to study the neutrino science and proton decay physics. This facility can be further exploited for the study of the ground breaking discoveries i.e. origin of matter, unification of forces, dark matter detection etc. In this work we have explored the DUNE potential for capturing the sub-GeV dark matter in viable dark matter parameter space. The scenario of sub-GeV dark matter range requires a light mediator that couples the hidden sector with the standard model. The choice of the mediator will decide the different channels by which dark matter …
We consider the use of directionality in the search for monoenergetic sub-GeV neutrinos arising from the decay of stopped kaons, which can be produced by dark matter annihilation in the core of the Sun. When these neutrinos undergo charged-current interactions with a nucleus at a neutrino detector, they often eject a proton which is highly peaked in the forward direction. The direction of this track can be measured at DUNE, allowing one to distinguish signal from background by comparing on-source and off-source event rates. We find that directional information can enhance the signal to backgro…
Many Beyond-Standard Model physics signatures are enhanced in high-energy neutrino interactions. To explore these signatures, ultra-large Cherenkov detectors such as IceCube exploit event samples with charged current muon neutrino interactions > 1 TeV. Most of these interactions occur below the detector volume, and produce muons that enter the detector. However, the large spacing between detectors leads to inefficiency for measuring muons with energies below or near the critical energy of 400 GeV. In response, IceCube has built a densely instrumented region within the larger detector. This pro…
Secret interactions of neutrinos with light new gauge bosons, $Z^\prime$, can lead to a rich phenomenology in supernova explosion as well as in the early Universe. This interaction can also lead to new decay modes for charged mesons, $π^+ (K^+) \to e^+ νZ'$, and subsequently to $Z'\to ν\barν$. After demonstrating that such an interaction can be accommodated within viable electroweak symmetric models, we study how the near detector (ND) of DUNE can probe this scenario. We also discuss how the DUNE ND can make it possible to reconstruct the flavor structure of the $Z^\prime$ coupling to neutrino…
Next generation neutrino oscillation experiments like DUNE and T2HK are multi-purpose observatories, with a rich physics program beyond oscillation measurements. A special role is played by their near detector facilities, which are particularly well-suited to search for weakly coupled dark sector particles produced in the primary target. In this paper, we demonstrate this by estimating the sensitivity of the DUNE near detectors to the scattering of sub-GeV DM particles and to the decay of sub-GeV sterile neutrinos ("heavy neutral leptons"). We discuss in particular the importance of the DUNE-P…
We study the sensitivity to sub-GeV dark sectors of high energy ($ \geq100$ GeV) proton fixed target experiments such as the Main Injector and the future Long-Baseline Neutrino Facility (LBNF). We focus on off-axis detectors since they have been shown to be the ideal location to reduce the neutrino background. We consider MiniBooNE as an off-axis detector for the NuMI facility and a hypotetical detector for LBNF located 200 m away from the target and 6.5 degrees off-axis. We find that with the existing data, MiniBoone can explore new regions of the parameter space for leptophobic dark forces i…
We show that, the decoherence phenomena applied to the neutrino system could lead us to have an observable breaking of the fundamental CPT symmetry. We require a specific textures of non-diagonal decoherence matrices, with non-zero $δ_{CP}$, for having such observations. Using the information from the CPT conjugate channels: $ν_μ \rightarrow ν_μ$ and $\barν_μ \rightarrow \barν_μ$ and its corresponding backgrounds, we have estimated the sensitivity of DUNE experiment for testing CPT under the previous conditions. Four scenarios for energy dependent decoherence parameters $Γ_{E_ν}=Γ\times (E_ν/\…
We introduce the mono-neutrino signal at neutrino detectors as a smoking gun of sub-GeV scale dark matter candidates that mainly interact with standard model neutrinos. In a mono-neutrino process, invisible particles, either dark matter themselves or the mediator particle, are radiated off a neutrino when it undergoes the charged-current weak interaction. The associated signals include a missing transverse momentum with respect to the incoming neutrino beam direction and the production of wrong-sign charged leptons. We demonstrate the potential leading role of the future DUNE experiment, using…
The low-energy $U(1)_{B-L}$ gauge symmetry is well-motivated as part of beyond Standard Model physics related to neutrino mass generation. We show that a light $B-L$ gauge boson $Z{'}$ and the associated $U(1)_{B-L}$-breaking scalar $φ$ can both be effectively searched for at high-intensity facilities such as the near detector complex of the Deep Underground Neutrino Experiment (DUNE). Without the scalar $φ$, the $Z{'}$ can be probed at DUNE up to mass of 1 GeV, with the corresponding gauge coupling $g_{BL}$ as low as $10^{-9}$. In the presence of the scalar $φ$ with gauge coupling to $Z{'}$, …
Highly energetic proton/electron beam fixed target experiments extends an opportunity to probe the sub-GeV dark matter and associated interactions. In this work we have explored the sensitivity of DUNE for sub-GeV leptophobic dark matter i.e. this dark matter barely couples with the leptons. Baryon number gauge theory can predicts the existence of a leptophobic cold dark matter particle candidates. In our work, the dark matter candidate is considered to be scalar whose mass is defined by the symmetry breaking of new baryonic gauge group $U(1)_{B}$. In this scenario a light scalar dark matter c…
We point out that the LDMX (Light Dark Matter eXperiment) detector design, conceived to search for sub-GeV dark matter, will also have very advantageous characteristics to pursue electron-nucleus scattering measurements of direct relevance to the neutrino program at DUNE and elsewhere. These characteristics include a 4-GeV electron beam, a precision tracker, electromagnetic and hadronic calorimeters with near 2$π$ azimuthal acceptance from the forward beam axis out to $\sim$40$^\circ$ angle, and low reconstruction energy threshold. LDMX thus could provide (semi)exclusive cross section measurem…
In this paper we show that the DUNE experiment can measure the Earth's density profile by analyzing atmospheric neutrino oscillations. The crucial feature that enables such measurement is the detailed event reconstruction capability of liquid argon time projection chambers. This allows for studying the sub-GeV atmospheric neutrino component, which bears a rich oscillation phenomenology, strongly dependent on the matter potential sourced by the Earth. We provide a pedagogical discussion of the MSW and parametric resonances and their role in measuring the core and mantle densities. By performing…
Current long-baseline neutrino-oscillation experiments such as NO$ν$A and T2K are mainly sensitive to physics in the neighbourhood of the first oscillation maximum of the $ν_μ\to ν_e$ oscillation probability. The future Deep Underground Neutrino Experiment (DUNE) utilizes a wide-band beam tune optimized for CP violation sensitivity that fully covers the region of the first maxima and part of the second. In the present study, we elucidate the role of second oscillation maximum in addressing issues pertaining to unknowns in the standard three flavour paradigm. We consider a new DUNE beam tune op…
We address some theoretical issues of the quantum decoherence phenomenon within the neutrino oscillation framework and carry out various tests under DUNE simulated experimental environment. On the theoretical side, we provide a general expression for an invariant decoherence matrix under a quantum basis rotation. On the simulated experimental side, considering a rotation invariant and a non-invariant decoherence matrix, we study the impact on the fitting of the standard oscillation parameters, the sensitivity in the mass hierarchy and CP violation, combining the neutrino and antineutrino mode …
The DUNE/LBNF program aims to address key questions in neutrino physics and astroparticle physics. Realizing DUNE's potential to reconstruct low-energy particles in the 10-100 MeV energy range will bring significant benefits for all DUNE's science goals. In neutrino physics, low-energy sensitivity will improve neutrino energy reconstruction in the GeV range relevant for the kinematics of DUNE's long-baseline oscillation program. In astroparticle physics, low-energy capabilities will make DUNE's far detectors the world's best apparatus for studying the electron-neutrino flux from a supernova. T…
Experiments measuring the parameters of active neutrino oscillations can also search for the sterile neutrinos in a part of sterile neutrino parameter space. In this paper, we analyze the prospects for the sterile neutrino search in the upcoming experiment DUNE for the sterile neutrinos with masses at GeV scale. As it relies on the still-undecided design of the Near Detector, we provide the expected number of the sterile neutrino decays in the Near Detector volume. Our most optimistic predictions show that the corresponding limit on mixing can be approximately of the same order as the previous…
We consider the sensitivity of the DUNE experiment to a heavy neutral lepton, HNL (also known as sterile neutrino) in the mass range from a few MeV to a few GeV, interacting with the Standard Model via a transition magnetic moment to the active neutrinos, the so-called dipole portal. The HNL is produced via the upscattering of active neutrinos, and the subsequent decay inside the detector provides a single-photon signal. We show that the tau-neutrino dipole portal can be efficiently probed at the DUNE far detector, using the tau-neutrino flux generated by neutrino oscillations, while the near …
We set constraints and future sensitivity projections on millicharged particles (MCPs) based on electron scattering data in numerous neutrino experiments, starting with MiniBooNE and the Liquid Scintillator Neutrino Detector (LSND). Both experiments are found to provide new (and leading) constraints in certain MCP mass windows: 5 - 35 MeV for LSND and 100 - 180 MeV for MiniBooNE. Furthermore, we provide projections for the ongoing Fermilab SBN program, the Deep Underground Neutrino Experiment (DUNE), and the proposed Search for Hidden Particles (SHiP) experiment. In the SBN program, SBND and M…
Even though neutrino oscillations have been conclusively established, there are a few unanswered questions pertaining to leptonic Charge Parity violation (CPV), mass hierarchy (MH) and $θ_{23}$ octant degeneracy. Addressing these questions is of paramount importance at the current and future neutrino experiments including the Deep Underground Neutrino Experiment (DUNE) which has a baseline of 1300 km. In the standard mode, DUNE is expected to run with a {\textit{low energy}} (LE) tuned beam which peaks around the first oscillation maximum ($2-3$ GeV) (and then sharply falls off as we go to hig…
The elliptic flow coefficient ($v_{2}$) of $ϕ$ mesons at mid-rapidity as a function of transverse momentum ($p_{T}$) is measured for Au+Au collisions at centre of mass energy ($\sqrt{s_{NN}}$) 27 and 54.4 GeV. The $v_{2}$ measurement is done using event plane from Time Projection Chamber (TPC, $|η|$ $<$1.0) and Event Plane Detectors (EPD, 2.1$<$$|η|$$<$5.1) for 54.4 and 27 GeV, respectively. A high precision test of the number of constituent quark scaling of $ϕ$ meson $v_{2}$ (by including measurements for other hadrons) has been shown. The results are compared to transport model (AMPT) calcul…
In this work, we predict the spectroscopy behavior of these light unflavored vector mesons with masses at the range of $2.4\sim 3$ GeV, which are still missing in the experiment. By presenting their mass spectrum and studying their two-body Okubo-Zweig-lizuka allowed decay widths, we discuss the possible experimental evidences of these discussed states combining with the present experimental data. Especially, we strongly suggest that our experimental colleagues carry out the exploration of these higher states via the $e^+e^-$ annihilation into light mesons. It is obvious that BESIII and Belle …
In this work, we study the high-spin states with masses below 3 GeV observed in experiments and we perform analysis of mass spectrum and investigation of strong decay behaviors of the high-spin states. Comparing our results with the experimental data, we can reveal the underlying properties of these high-spin states; more importantly, we also predict their abundant decay features, which can provide valuable information for experimental exploration of these high-spin states.
Heavy nearly-sterile neutrinos are a common ingredient in extensions of the Standard Model which aim to explain neutrino masses, like for instance in Type I seesaw models, or one of its variants. If the scale of the new Heavy Neutral Leptons (HNLs) is sufficiently low, observable signatures can arise in a range of current and upcoming experiments, from the LHC to neutrino experiments. In this article, we discuss the phenomenology of sterile neutrinos in the MeV to GeV mass range, focusing on their decays. We embed our discussion in a realistic mass model and consider the resulting implications…
The properties of the light vector meson states around 2.0 GeV have been poorly understood for a long time, which has become a barrier to the expansion to higher light vector meson spectrum. Recently, the BESIII collaboration released the measurements of the $e^+ e^- \to ωπ^0$ and $e^+ e^- \to ρη^{\prime}$ reactions above 2.0 GeV, both of which are ideal processes to study the isovector $ρ$ meson family. In this work, through carrying out a combined analysis of the Born cross section data for the above two processes with the theoretical support on mass spectrum, and production and strong decay…
The masses of excited charmed mesons are shown to decrease by $\sim (50-150)$~MeV due to a flattening of the confining potential at large distances, which effectively takes into account open decay channels. The scale of the mass shifts is similar to that in charmonium for $ψ(4660)$ and $χ_{c0}(4700)$. The following masses of the first excitations: $M(2\,{}^3P_0)=2874$~MeV, $M(2\,{}^3P_2)=2968$~MeV, $M(2\,{}^3D_1)=3175$~MeV, and $M(2\,{}^3D_3)=3187$~MeV, and second excitations: $M(3\,{}^1S_0)=3008$~MeV, $M(3\,{}^3S_1)=3062$~MeV, $M(3\,{}^3P_0)=3229$~MeV, and $M(3\,{}^3P_2) =3264$~MeV, are predi…
This work is devoted to search and study scalar $σ_0 0^+[0^++]$ - mesons in the system of $π^+π^-$ from the reaction $np -> npπ^+π^-$ at the impulse of the quasimonochromatic neutrons c from the data obtained in an exposure of the 1m H2 bubble chamber of LHE (JINR)The resonance with and has been found out in effective mass distribution. Value of a statistical deviation of this peculiarity from a background is more than four. Spin of the resonance has been estimated, which, with high probability, is equal 0. The other quantum numbers of the resonance have been estimated.
We review the recent progress in modelling neutrino-nucleus scattering, in a framework based on scaling which describes simultaneously the nuclear response to electromagnetic and weak probes. The study is relevant for the analysis of neutrino oscillation data and the design of the next generation experiments Hyper-Kamiokande and DUNE.
We briefly review the status of various conventional quark-antiquark mesons below 2 GeV and outline some open questions: the status of the strange-antistrange orbitally excited vector meson, the status of the nonet of axial-tensor mesons (chiral partners of the well known tensor mesons), and the isoscalar mixing angle in the pseudotensor sector, which can eventually represent a novel manifestation of the chiral anomaly.
Properties of scalar mesons below 1.0 GeV have been studied by regarding them as hadronic molecular states. Using the effective Lagrangian approach, we have calculated their leptonic decays, strong decays and productions via the $ϕ$ meson radiative decays. Comparing our results with that given in the literature and the data, we conclude that it is difficult to arrange them in the same nonet if some of them are pure hadronic molecules.
The 125 GeV resonance discovered at the LHC could be a heavy quarkonium pseudoscalar meson. The diagonalization of the mass matrix of the isoscalar quarkonium states $|ζ>$ and $|ζ^{0'}>$ produces the states identified with the pseudoscalar heavy quarkonium mesons $ζ^0$ and $ζ^{0'}$. For a mixing angle $ϕ\sim 36\,^{\circ}$ the mass of the bound state pseudoscalar resonance $ζ^0$ is $m_{ζ^0}\sim 125$ GeV. The decay rates of the quarkonium $ζ^0$ meson are estimated and compared to the standard model Higgs boson predictions. The importance of determining the spin-parity of the 125 GeV resonance is…
Within the context of a generalized linear sigma model that includes two nonets of scalar mesons (a two-quark nonet and a four-quark nonet) and two nonets of pseudoscalar mesons (a two-quark nonet and a four-quark nonet) a collective description of scalar and pseudoscalar mesons below and above 1 GeV is studied. The quark contents of these states are probed; estimates on their quark components are extracted; and prediction for pi pi scattering amplitude is made. An overview of these studies is presented here.
The origin of neutrino mass is a big unsolved problem of the Standard Model (SM) that motivate us to consider beyond the SM (BSM) scenarios where SM-singlet right-handed neutrinos (RHNs) are introduced to explain the origin of the light neutrino masses through the seesaw mechanism. There is a variety of ways which could lead us to this goal and one of them is a general U$(1)$ extension of the SM. In this scenario, three SM-singlet RHNs are introduced to cancel the gauge and mixed gauge gravity anomalies. After anomaly cancellation, we notice that the left- and right-handed charged fermions are…
