The search for relativistic scattering signals of cosmogenic light dark matter at terrestrial detectors has received increasing attention as an alternative approach to probe dark-sector physics. Large-volume neutrino experiments are well motivated for searches of dark matter that interacts very weakly with Standard Model particles and/or that exhibits a small incoming flux. We perform a dedicated signal sensitivity study for a detector similar to the one proposed by the DUNE Collaboration for cosmogenic dark-matter signals resulting from a non-minimal multi-particle dark-sector scenario. The liquid argon time projection chamber technology adopted for the DUNE detectors is particularly suited for searching for complicated signatures owing to good measurement resolution and particle identification, as well as $dE/dx$ measurements to recognize merged tracks. Taking inelastic boosted dark matter as our benchmark scenario that allows for multiple visible particles in the final state, we demonstrate that the DUNE far detectors have a great potential for probing scattering signals induced by relativistic light dark matter. Detector effects and backgrounds have been estimated and taken into account. Model-dependent and model-independent expected sensitivity limits for a DUNE-like detector are presented.
When neutrino masses arise from the exchange of neutral heavy leptons, as in most seesaw schemes, the effective lepton mixing matrix $N$ describing neutrino propagation is non-unitary, hence neutrinos are not exactly orthonormal. New CP violation phases appear in $N$ that could be confused with the standard phase $δ_{\text{CP}}$ characterizing the three neutrino paradigm. We study the potential of the long-baseline neutrino experiment DUNE in probing CP violation induced by the standard CP phase in the presence of non-unitarity. In order to accomplish this we develop our previous formalism, so…
We study the possibility of probing different texture zero neutrino mass matrices at long baseline neutrino experiment DUNE. Assuming a diagonal charged lepton basis and Majorana nature of light neutrinos, we first classify the possible light neutrino mass matrices with one and two texture zeros and then numerically evaluate the parameter space in terms of atmospheric mixing angle $θ_{23}$ and Dirac CP phase $δ_{\text{CP}}$ which satisfies the texture zero conditions. We then feed these parameter values into the numerical analysis in order to study the sensitivity of DUNE experiment to them. W…
We investigate the capability of the DUNE Near Detector (ND) to constrain Non Standard Interaction parameters (NSI) describing the production of neutrinos ($\varepsilon_{αβ}^s$) and their detection ($\varepsilon_{αβ}^d$). We show that the DUNE ND is able to reject a large portion of the parameter space allowed by DUNE Far Detector analyses and to set the most stringent bounds from accelerator neutrino experiments on $|\varepsilon_{μe}^{s,d}|$ for wide intervals of the related phases. We also provide simple analytic understanding of our results as well as a numerical study of their dependence o…
The presence of non-unitary neutrino mixing can affect the measurement of the three-neutrino leptonic Dirac CP phase and hamper efforts to probe CP violation due to degeneracies of the extra non-unitary CP phase with the standard CP phase. We study the effect of including non-unitarity on probing CP violation with the long-baseline experiments NO$ν$A, T2K and DUNE. We analyze the effect of non-unitary mixing at the level of oscillation probabilities associated with the relevant baselines, and present the CP violation sensitivity for the individual experiments and their combination. Our results…
We discuss the impact of non-standard neutrino matter interactions (NSI) in propagation on the determination of CP phase in the context of the long baseline accelerator experiments such as Deep Underground Neutrino Experiment (DUNE). DUNE will mainly address the issue of CP violation in the leptonic sector. Here we study the role of NSI and its impact on the question of observing the CP violation signal at DUNE. We consider two scenarios of oscillation with three active neutrinos in absence and presence of NSI. We elucidate the importance of ruling out subdominant new physics effects introduce…
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 $Γ_{E_ν}=Γ\times (E_ν/\…
Probing non-unitarity of the PMNS matrix in P2SO and comparison with DUNE
School of Physics, University of Hyderabad（海德拉巴大学物理学院）；Center of Excellence for Advanced Materials and Sensing Devices, Ruđer Bošković Institute（鲁德·博什科维奇研究所先进材料与传感设备卓越中心）
S. N. Bose National Centre for Basic Sciences（S.N. 玻色基础科学国家中心）；Theoretical Physics Division, Physical Research Laboratory（物理研究实验室理论物理部）；Division of Sciences, Krea University（克里亚大学理学院）
We study the sensitivity to sub-GeV dark sectors of high energy ($ \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 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…
Probing Light Dark Particles in Neutrino Scattering Experiments
Southeast University（东南大学）；Tsung-Dao Lee Institute & School of Physics and Astronomy, Shanghai Jiao Tong University（李政道研究所与上海交通大学物理与天文学院）；Shanghai Jiao Tong University（上海交通大学）；Peking University（北京大学）
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 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…
Neutrino and dark matter experiments with large-volume ($\gtrsim 1$ ton) detectors can provide excellent sensitivity to signals induced by energetic light dark matter coming from the present universe. Taking boosted dark matter as a concrete example of energetic light dark matter, we scrutinize two representative search channels, electron scattering and proton scattering including deep inelastic scattering processes, in the context of elastic and inelastic boosted dark matter, in a completely detector-independent manner. In this work, a dark gauge boson is adopted as the particle to mediate th…
While most searches for cosmic axions so far focused on their cold relics as (a component of) dark matter, various well-motivated cosmological sources can produce "boosted" axions that remain relativistic today. We demonstrate that existing/upcoming neutrino experiments such as Super-Kamiokande, Hyper-Kamiokande, DUNE, JUNO, and IceCube can probe such energetic axion relics. The characteristic signature is the mono-energetic single photon signal from axion absorption induced by the axion-photon coupling. This proposal offers to cover parameter ranges that are complementary to existing axion se…
Neutrino flavour oscillation is one of the primary indication of the existence of new physics beyond standard model. The presence of small neutrino mass is indispensable to explicate the oscillation among different flavours of neutrino. By the addition of a right handed neutral lepton with the standard model fermions, it is possible to generate tiny neutrino mass. Such additional fermion may induce non-unitarity to the $3\times 3$ PMNS mixing matrix which influences the propagation of neutrino in space-time. In this work the effect of non-unitary mixing matrix is analyzed in neutrino oscillati…
This paper investigates the collider phenomenolgy of a minimal nonthermal dark matter model with a 1-GeV dark matter candidate, which naturally explain baryongensis. Since the light dark matter is not parity-protected, it can be singly produced at the LHC. This leads to large missing energy associated with an energetic jet whose transverse momentum distribution is featured by a Jacobian-like shape. The monojet, dijet, paired dijet and 2 jets + missing energy channels are studied. Currently existing data at Tevatron and LHC offer significant bounds on our model.
We investigate properties of an energetic atom propagating through strongly interacting atomic gases. The operator product expansion is used to systematically compute a quasiparticle energy and its scattering rate both in a spin-1/2 Fermi gas and in a spinless Bose gas. Reasonable agreement with recent quantum Monte Carlo simulations even at a relatively small momentum k/kF>1.5 indicates that our large-momentum expansions are valid in a wide range of momentum. We also study a differential scattering rate when a probe atom is shot into atomic gases. Because the number density and current densit…
Realistic superstring models generically give rise to exotic matter states, which arise due to the ``Wilson-line'' breaking of the non-Abelian unifying gauge symmetry. Often such states are protected by a gauge or local discrete symmetry and therefore may be stable or meta-stable. We study the possibility of a flux of high energy neutrinos coming from the sun and the earth due to the annihilation of such exotic string states. We also discuss the expected flux for other heavy stable particles -- like the gluino LSP. We comment that the detection of ultra-energetic neutrinos from the sun and the…
Axion-like particles (ALPs) provide a promising direction in the search for new physics, while a wide range of models incorporate ALPs. We point out that future neutrino experiments, such as DUNE, possess competitive sensitivity to ALP signals. The high-intensity proton beam impinging on a target can not only produce copious amounts of neutrinos, but also cascade photons that are created from charged particle showers stopping in the target. Therefore, ALPs interacting with photons can be produced (often energetically) with high intensity via the Primakoff effect and then leave their signatures…
Non-standard neutrino interactions with a massive boson can produce the bosons in the core of core-collapse supernovae (SNe). After the emission of the bosons from the SN core, their subsequent decays into neutrinos can modify the SN neutrino flux. We show future observations of neutrinos from a next galactic SN in Super-Kamiokande (SK) and Hyper-Kamiokande (HK) can probe flavor-universal non-standard neutrino couplings to a light boson, improving the previous limit from the SN 1987A neutrino burst by several orders of magnitude. We also discuss sensitivity of the flavor-universal non-standard…
We investigate the prospects for probing the strength of the possible matter nonstandard neutrino interactions (mNSI) in long baseline neutrino oscillation experiments and the interference of the leptonic CP angle $δ_{CP}$ with the constraining of the mNSI couplings. The interference is found to be strong in the case of the $ν_e \leftrightarrow ν_μ$ and $ν_e \leftrightarrow ν_τ$ transitions but not significant in the other cases. We use SPS and DUNE setups as benchmarks.
There are broadly three channels to probe axion-like particles (ALPs) produced in the laboratory: through their subsequent decay to Standard Model (SM) particles, their scattering with SM particles, or their subsequent conversion to photons. Decay and scattering are the most commonly explored channels in beam-dump type experiments, while conversion has typically been utilized by light-shining-through-wall (LSW) experiments. A new class of experiments, dubbed PASSAT (Particle Accelerator helioScopes for Slim Axion-like-particle deTection), has been proposed to make use of the ALP-to-photon conv…
Probing Azimuthal Alignment in Heavy-Ion Collisions: Clusterization Effects
Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research（鲍戈留博夫理论物理实验室，核物理联合研究所）；Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University（斯考别尔钦核物理研究所，莫斯科国立罗蒙诺索夫大学）
The particle kinetic energies of pp fusion in the sun (Gamow Energy) produce small changes in the energies of pp solar neutrinos relative to those due only to exothermal energetics. Observation of this effect may be possible via the unique tools of the upcoming LENS solar neutrino detector. The temperature profile of energy production in the sun may thus be directly probed for the first time.
We study the probing prospects of cosmic ray boosted dark matter (DM) in the framework of simplified electron-philic dark photon model. Focusing on the dark matter and dark photon masses around keV $\sim $ MeV scale, we consider the bounds obtained from the XENON1T and Super-K experiments. The electron bound state effects are treated carefully in calculating the XENON1T constraint. As for the detection at neutrino detector where the energy threshold is relatively higher, the large logarithmic effects induced by the scale hierarchy between the masses and momentum transfer are considered by intr…
The present experimental status does not exclude weak-strength non-standard interactions of neutrinos with electrons. These interactions can be revealed in solar neutrino experiments. Our discussion covers several aspects related to this issue. First, we perform an analysis of the Super Kamiokande and SNO data to investigate their sensitivity to such interactions. In particular, we show that the ν_e oscillation into sterile neutrinos can be still allowed if ν_e has extra interactions of the proper strength. Second, we suggest that the Borexino detector can provide good signatures for these non…
We consider nucleon-decay-like signatures of the hylogenesis, a variant of the antibaryonic dark matter model. For the interaction between visible and dark matter sectors through the neutron portal, we calculate the rates of dark matter scatterings off neutron which mimic neutron-decay processes $n\to νγ$ and $n\to νe^+ e^-$ with richer kinematics. We obtain bounds on the model parameters from nonobservation of the neutron decays by applying the kinematical cuts adopted in the experimental analyses. The bounds are generally (much) weaker than those coming from the recently performed study of e…
Probing hidden sectors with a muon beam: implication of spin-0 dark matter mediators for muon $(g-2)$ anomaly and validity of the Weiszäcker-Williams approach
Detecting dark matter (DM) relic via freeze-in is difficult in laboratories due to smallness of the couplings involved. However, a non-standard cosmological history of the Universe, prior to Big Bang Nucleosynthesis (BBN), can dramatically change this scenario. In this context, we study the freeze-in production of dark matter in classically scale invariant $U(1)_X$ gauge extension of the Standard Model (SM), recently dubbed as the \textit{Scale Invariant FIMP Miracle}. We assume an additional species dominates the energy density of the Universe at early times, causing the expansion rate at a g…
Probing Neutrino Compositeness with Invisible and Displaced Signals
INFN, Sezione di Firenze（意大利国家核物理研究所佛罗伦萨分部）；Department of Physics and Astronomy, University of Florence（佛罗伦萨大学物理与天文学系）；Perimeter Institute for Theoretical Physics（理论物理珀米特研究所）；Galileo Galilei Institute for Theoretical Physics（伽利略·伽利莱理论物理研究所）
The highest energy cosmic rays observed possess macroscopic energies and their origin is likely to be associated with the most energetic processes in the Universe. Their existence triggered a flurry of theoretical explanations ranging from conventional shock acceleration to particle physics beyond the Standard Model and processes taking place at the earliest moments of our Universe. Furthermore, many new experimental activities promise a strong increase of statistics at the highest energies and a combination with gamma-ray and neutrino astrophysics will put strong constraints on these theoreti…
New light, weakly coupled particles can be efficiently produced at existing and future high-intensity accelerators and radioactive sources in deep underground laboratories. Once produced, these particles can scatter or decay in large neutrino detectors (e.g Super-K and Borexino) housed in the same facilities. We discuss the production of weakly coupled scalars $ϕ$ via nuclear de-excitation of an excited element into the ground state in two viable concrete reactions: the decay of the $0^+$ excited state of $^{16}$O populated via a $(p,α)$ reaction on fluorine and from radioactive $^{144}$Ce dec…
Neutrino interaction uncertainties are a limiting factor in current and next-generation experiments probing the fundamental physics of neutrinos, a unique window on physics beyond the Standard Model. Neutrino-nucleon scattering amplitudes are an important part of the neutrino interaction program. However, since all modern neutrino detectors are composed primarily of heavy nuclei, knowledge of elementary neutrino-nucleon amplitudes relies heavily on experiments performed in the 1970s and 1980s, whose statistical and systematic precision are insufficient for current needs. In this white paper, w…
We investigate the potential of Liquid Argon (LAr) neutrino detectors to search for millicharged particles, a well-motivated extension of the standard model. Detectors located downstream of an intense proton beam that is striking a target may be exposed to a large flux of millicharged particles. Millicharged particles interact primarily through low momentum exchange producing electron recoil events near detector threshold. Recently, sub-MeV detection capabilities were demonstrated by the Fermilab ArgoNeuT detector, a small LAr detector which was exposed to the NuMI neutrino beam. Despite high …
We perform a feasibility study to search for axion-like particles (ALPs) using vector boson fusion (VBF) processes at the LHC. We work in an effective field theory framework with cutoff scale $Λ$ and ALP mass $m_{a}$, and assume that ALPs couple to photons with strength $\propto 1/Λ$. Assuming proton-proton collisions at $\sqrt{s} = 13$ TeV, we present the total VBF ALP production cross sections, ALP decay widths and lifetimes, and relevant kinematic distributions as a function of $m_{a}$ and $Λ$. We consider the $a\toγγ$ decay mode to show that the requirement of an energetic diphoton pair co…
