When solving the solar neutrino problem on the basis of the hypothesis of the existence of a new interaction between electron neutrinos and nucleons, carried by a massless pseudoscalar boson, it becomes necessary to find the consequences of the short-term Brownian motion of neutrinos in the Sun. Earlier, we transmitted these consequences by the effective number of collisions of a neutrino with nucleons of the Sun, assuming the equality of fluxes near the Earth of left- and right-handed solar neutrinos. In this paper, we analyze the transfer of the mentioned consequences by a test geometric distribution of collisions with one free parameter. This distribution provides good agreement between theoretical and experimental results for all five observed processes with solar neutrinos, while it gives the ratio of fluxes near the Earth of left- and right-handed neutrinos equal to 0.516:0.484. With such a ratio, the acceptability of the method of the effective number of collisions of a neutrino with nucleons is again confirmed.
After scattering off nuclei in the Sun, dark matter particles can be gravitationally captured by the Sun, accumulate in the Sun's core and annihilate into Standard Model particles. Neutrinos originating from these annihilations can be detected by the IceCube Neutrino Observatory, located at the South Pole. Due to the non-observation of these neutrinos, constraints on the standard spin-dependent and spin-independent dark matter-nucleon scattering cross sections have been placed. Based on these constraints, we present upper limits on the coupling constants of the non-relativistic effective theor…
The annihilation of dark matter (DM) particles accumulated in the Sun could produce a flux of neutrinos, which is potentially detectable with neutrino detectors/telescopes and the DM elastic scattering cross section can be constrained. Although the process of DM capture in astrophysical objects like the Sun is commonly assumed to be due to interactions only with nucleons, there are scenarios in which tree-level DM couplings to quarks are absent, and even if loop-induced interactions with nucleons are allowed, scatterings off electrons could be the dominant capture mechanism. We consider this p…
The Sun Can Strongly Constrain Spin-Dependent Dark Matter Nucleon Scattering Below the Evaporation Limit
Stockholm University（斯德哥尔摩大学）；The Oskar Klein Centre for Cosmoparticle Physics（奥斯卡·克莱因宇宙粒子物理中心）；Friedrich-Alexander-Universität Erlangen-Nürnberg（埃尔朗根-纽伦堡弗里德里希-亚历山大大学）
We consider the prospects for studying spin-independent isospin-violating dark matter-nucleon interactions with neutrinos from dark matter annihilation in the Sun, with a focus on IceCube/DeepCore (IC/DC). If dark matter-nucleon interactions are isospin violating, IC/DC's reach in the spin-independent cross section may be competitive with current direct detection experiments for a wide range of dark matter masses. We also compare IC/DC's sensitivity to that of next generation argon, germanium, neon and xenon based detectors.
We discuss a limitation on extracting bounds on the scattering cross section of dark matter with nucleons, using neutrinos from the Sun. If the dark matter particle is sufficiently light (less than about 4 GeV), the effect of evaporation is not negligible and the capture process goes in equilibrium with the evaporation. In this regime, the flux of solar neutrinos of dark matter origin becomes independent of the scattering cross section and therefore no constraint can be placed on it. We find the minimum values of dark matter masses for which the scattering cross section on nucleons can be prob…
In the effective theory of isoscalar and isovector dark matter-nucleon interactions mediated by a heavy spin-1 or spin-0 particle, 8 isotope-dependent nuclear response functions can be generated in the dark matter scattering by nuclei. We compute the 8 nuclear response functions for the 16 most abundant elements in the Sun, i.e. H, $^{3}$He, $^{4}$He, $^{12}$C, $^{14}$N, $^{16}$O, $^{20}$Ne, $^{23}$Na, $^{24}$Mg, $^{27}$Al, $^{28}$Si, $^{32}$S, $^{40}$Ar, $^{40}$Ca, $^{56}$Fe, and $^{58}$Ni, through numerical shell model calculations. We use our response functions to compute the rate of dark m…
Broad disagreement persists between helioseismological observables and predictions of solar models computed with the latest surface abundances. Here we show that most of these problems can be solved by the presence of asymmetric dark matter coupling to nucleons as the square of the momentum $q$ exchanged in the collision. We compute neutrino fluxes, small frequency separations, surface helium abundances, sound speed profiles and convective zone depths for a number of models, showing more than a $6σ$ preference for $q^2$ models over others, and over the Standard Solar Model. The preferred mass …
A finite axion-nucleon coupling, nearly unavoidable for QCD axions, leads to the production of axions via the thermal excitation and subsequent de-excitation of Fe-57 isotopes in the sun. We revise the solar bound on this flux adopting the up to date emission rate, and investigate the sensitivity of the proposed International Axion Observatory IAXO and its intermediate stage BabyIAXO to detect these axions. We compare different realistic experimental options and discuss the model dependence of the signal. Already BabyIAXO has sensitivity far beyond previous solar axion searches via the nucleon…
The physics of the solar dark matter (DM) that are captured and thermalise through the DM-nucleon interaction has been extensively studied. In this work, we consider the leptophilic DM scenario where the DM particles interact exclusively with the electrons through the axial-vector coupling. We investigate relevant phenomenologies in the Sun, including its capture, evaporation and thermalisation, and we calculate the equilibrium distribution using the Monte Carlo methods, rather than adopting a semi-analytic approximation. Based on the analysis, we then determine the minimum testable mass for w…
We consider the scattering of the brane fields due to t-channel massive graviton exchanges in the Randall-Sundrum model. The eikonal amplitude is analytically calculated and both differential and total neutrino-nucleon cross sections are estimated. The event rate of quasi-horizontal air showers induced by cosmic neutrinos, which can be detected at the Pierre Auger Observatory, is presented for two different fluxes of cosmogenic neutrinos.
We argue that the detection of neutrino signature from the Earth core is an ideal approach for probing the coupling of heavy dark matter ($m_χ>10^{4}$ GeV) to nucleons. We first note that direct searches for dark matter (DM) in such a mass range do not provide stringent constraints. Furthermore the energies of neutrinos arising from DM annihilations inside the Sun cannot exceed a few TeV at the Sun surface due to the attenuation effect. Therefore the sensitivity to the heavy DM coupling is lost. Finally, the detection of neutrino signature from galactic halo can only probe DM annihilation cros…
We argue that the detection of neutrino signature from the Earth's core can effectively probe the coupling of heavy dark matter ($m_χ>10^{4}$ GeV) to nucleons. We first note that direct searches for dark matter (DM) in such a mass range provide much less stringent constraint than the constraint provided by such searches for $m_χ\sim 100$ GeV. Furthermore the energies of neutrinos arising from DM annihilation inside the Sun cannot exceed a few TeVs at the Sun surface due to the attenuation effect. Therefore the sensitivity to the heavy DM coupling is lost. Finally, the detection of neutrino sig…
The halo dark matter (DM) can be gravitationally captured by the Sun. For self-interacting DM (SIDM), we show that the number of DM trapped inside the Sun remains unsuppressed even if the DM-nucleon cross section is negligible. We consider a SIDM model where $U(1)$ gauge symmetry is introduced to account for the DM self-interaction. Such a model naturally leads to isospin violation for DM-nucleon interaction, although isospin symmetry is still allowed as a special case. We show that the detection of neutrino signature from DM annihilation in the Sun can probe those SIDM parameter ranges not re…
We study the effects of energy transport in the Sun by asymmetric dark matter with momentum and velocity-dependent interactions, with an eye to solving the decade-old Solar Abundance Problem. We study effective theories where the dark matter-nucleon scattering cross-section goes as $v_{\rm rel}^{2n}$ and $q^{2n}$ with $n = -1, 0, 1 $ or $2$, where $v_{\rm rel}$ is the dark matter-nucleon relative velocity and $q$ is the momentum exchanged in the collision. Such cross-sections can arise generically as leading terms from the most basic nonstandard DM-quark operators. We employ a high-precision s…
Weakly interacting massive particles (WIMPs) can be gravitationally captured by the Sun and trapped in its core. The annihilation of those WIMPs into Standard Model particles produces a spectrum of neutrinos whose energy distribution is related to the dark matter mass. In this work, we present the theoretical framework for relating an observed neutrino flux to the WIMP-nucleon cross section and summarize a previous solar WIMP search carried out by IceCube. We then outline an ongoing updated solar WIMP search, focusing on improvements over the previous search.
The origin of the ultra high energy cosmic ray (UHECR) showers has remained as a mystery among particle physicists and astrophysicists. In low scale gravity models, where the neutrino-nucleon cross section rises to typical hadronic values at energies above $10^{20}$ eV, the neutrino becomes a candidate for the primary that initiates these showers. We calculate the neutrino-nucleon cross section at ultra high energies by assuming that it is dominated by the production of p-branes. We show, using a generalized Randall-Sundrum model, that the neutrino-nucleon cross-section at neutrino energies of…
We study the indirect detection of dark matter through neutrino flux from their annihilation in the center of the Sun, in a class of theories where the dark matter-nucleon spin-independent interactions break the isospin symmetry. We point out that, while the direct detection bounds with heavy targets like Xenon are weakened and reconciled with the positive signals in DAMA and CoGeNT experiments, the indirect detection using neutrino telescopes can impose a relatively stronger constraint and brings tension to such explanation, if the annihilation is dominated by heavy quark or $τ$-lepton final …
We combine experimental constraints from direct detection searches and from neutrino telescopes looking for WIMP annihilations in the Sun to derive halo-independent bounds on each of the 28 WIMP-proton and WIMP-neutron couplings of the effective non-relativistic Hamiltonian that drives the scattering process off nuclei of a WIMP of spin 1/2. The method assumes that the velocity distribution is normalized to one and homogeneous at the the solar system scale, as well as equilibrium between WIMP capture and annihilation in the Sun, and requires to fix the WIMP annihilation channels (we assume $b\…
A new concept is proposed to solve the solar neutrino problem, that is based on a hypothesis about the existence of a new interaction of electron neutrinos with nucleons mediated by massless pseudoscalar bosons. At every collision of a neutrino with nucleons of the Sun, its handedness changes from left to right and vice versa, and its energy decreases. The postulated hypothesis, having only one free parameter, provides a good agreement between the calculated and experimental characteristics of all five observed processes with solar neutrinos.
A new concept is proposed to solve the solar neutrino problem, that is based on a hypothesis about the existence of semi-weak interaction of electron neutrinos with nucleons mediated by massless pseudoscalar bosons. Owing to about 10 collisions of a solar neutrino with nucleons of the Sun, the fluxes of left- and right-handed solar neutrinos at the Earth surface are approximately equal, and their spectrum is changed in comparison with the one at the production moment. The postulated model with one free parameter provides a good agreement between the calculated and experimental characteristics …
NuSTAR as an Axion Helioscope: probing axion-nucleon and axion-electron couplings
Università di Torino（都灵大学）；Istituto Nazionale di Fisica Nucleare, Sezione di Torino（意大利国家核物理研究所都灵分部）；Technische Universität Dortmund（多特蒙德工业大学）；University of Zaragoza（萨拉戈萨大学）；Leinweber Institute for Theoretical Physics, University of California, Berkeley（加州大学伯克利分校莱因韦伯理论物理研究所）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）
Celestial objects such as stars and planets might be able to capture a large amount of dark matter particles through dark matter-nucleon scattering. Many previous studies have considered different celestial objects such as the Sun and the Earth as natural dark matter detectors and obtained some stringent bounds of the dark matter-nucleon scattering cross section. In this study, we use the $\sim 10$ MeV electron neutrino flux limits obtained by the Super-Kamiokande experiment and consider the Earth as a large natural dark matter detector to constrain the dark matter-nucleon scattering cross sec…
It has been recently pointed out that a momentum-dependent coupling of the asymmetric Dark Matter (ADM) with nucleons can explain the broad disagreement between helioseismological observables and the predictions of standard solar models. In this paper, we propose a minimal simplified ADM model consisting of a scalar and a pseudoscalar mediator, in addition to a Dirac fermionic DM, for generating such momentum-dependent interactions. Remarkably, the pseudoscalar with mass around 750 GeV can simultaneously explain the solar anomaly and the recent diphoton excess observed by both ATLAS and CMS ex…
Interactions with neutrons and protons play a crucial role for the neutrino opacity of matter in the supernova core. Their current implementation in many simulation codes, however, is rather schematic and ignores not only modifications for the correlated nuclear medium of the nascent neutron star, but also free-space corrections from nucleon recoil, weak magnetism or strange quarks, which can easily add up to changes of several 10% for neutrino energies in the spectral peak. In the Garching supernova simulations with the Prometheus-Vertex code, such sophistications have been included for a lon…
We consider the capture of dark matter in the Sun by inelastic scattering against nuclei as in the inelastic dark matter scenario. We show that, assuming a WIMP-nucleon cross-section of σ_n = 10^{-40}\cm^2 the resulting capture rate and density are sufficiently high so that current bounds on the muon neutrino flux from the Sun rule out any appreciable annihilation branching ratio of WIMPs into W^+W^-, Z^0Z^0, τ^+τ^-, t\bar{t} and neutrinos. Slightly weaker bounds are also available for annihilations into b\bar{b} and c\bar{c}. Annihilations into lighter particles that may produce neutrinos, su…
Annihilation of dark matter particles accumulated in the Sun would produce a flux of high-energy neutrinos whose prospects of detection in neutrino telescopes and detectors have been extensively discussed in the literature. However, for annihilations into Standard Model particles, there would also be a flux of neutrinos in the MeV range from the decays at rest of muons and positively charged pions. These low-energy neutrinos have never been considered before and they open the possibility to also constrain dark matter annihilation in the Sun into e+e-, mu+mu- or light quarks. Here we perform a …
Radiative seesaw models have the attractive property of providing dark matter candidates in addition to generation of neutrino masses. Here we present a study of neutrino signals from the annihilation of dark matter particles which have been gravitationally captured in the Sun, in the framework of the scotogenic model. We compute expected event rates in the IceCube detector in its 86-string configuration. As fermionic dark matter does not accumulate in the Sun, we study the case of scalar dark matter, with a scan over the parameter space. Due to a naturally small mass splitting between the two…
I study the process of dark matter capture by the Sun, under the assumption of a Weakly Interacting Massive Particle (WIMP), in the framework of non-relativistic effective field theory. Hypothetically, WIMPs from the galactic halo can scatter against atomic nuclei in the solar interior, settle to thermal equilibrium with the solar core and annihilate to produce an observable flux of neutrinos. In particular, I examine the thermalization process using Monte-Carlo integration of WIMP trajectories. I consider WIMPs in a mass range of 10--1000 GeV and WIMP-nucleon interaction operators with differ…
The strategy of modern effective field theory is exploited to pin down accurately the flux $S$ factors for the $pp$ and $hep$ processes in the Sun. The technique used is to combine the high accuracy established in few-nucleon systems of the "standard nuclear physics approach" (SNPA) and the systematic power counting of chiral perturbation theory (ChPT) into a consistent effective field theory framework. Using highly accurate wave functions obtained in the SNPA and working to \nlo3 in the chiral counting for the current, we make totally parameter-free and error-controlled predictions for the $p…
We examine the JEM-EUSO sensitivity to gravity effects in the context of Randall-Sundrum (RS) model with a single extra dimension and small curvature of the metric. Exchanges of reggeized Kaluza-Klein gravitons in the $t$-channel contribute to the inelastic cross-section for scattering of ultra-high-energy neutrinos off nucleons. Such effects can be detected in deeply penetrating quasi-horizontal air showers induced by interactions of cosmic neutrinos with atmospheric nucleons. For this reason, we calculate the expected number of quasi-horizontal air showers at the JEM-EUSO observatory as a fu…
As a part of the effort to investigate the implications of dark matter (DM)-nucleon effective interactions on the solar DM detection, in this paper we focus on the evaporation of the solar DM for a set of the DM-nucleon spin-independent (SI) effective operators. In order to put the evaluation of the evaporation rate on a more reliable ground, we calculate the non-thermal distribution of the solar DM using the Monte Carlo methods, rather than adopting the Maxwellian approximation. We then specify relevant signal parameter spaces for the solar DM detection for various SI effective operators. Bas…
We explore the singlet scalar dark matter (DM) from direct detections and high energy neutrino signals generated by the solar DM annihilation. Two singlet scalar DM models are discussed, one is the real singlet scalar DM model as the simple extension of the standard model (SSDM-SM) with a discrete Z_2 symmetry, and another is the complex singlet scalar DM model as the simple extension of the left-right symmetric two Higgs bidoublet model (SSDM-2HBDM) with $P$ and CP symmetries. To derive the Sun capture rate, we consider the uncertainties in the hadronic matrix elements and calculate the spin-…
A potential flux of high-energy neutrinos from the annihilation of dark matter particles trapped within the Sun has been exploited to place indirect limits on particle dark matter. In most models, the dark matter interacts weakly, but the possibility of a dark matter particle with a large cross section for elastic scattering with itself has been proposed in several contexts. I study the consequences of such dark matter self-interactions for the high-energy neutrino flux from annihilation within the Sun. The self-interaction may allow dark matter in the halo to be captured within the Sun by sca…
We study the thermal transport occurring in the system of solar captured dark matter (DM) and explore its impact on the DM indirect search signal. We particularly focus on the scenario of self-interacting DM (SIDM). The flows of energies in and out of the system are caused by solar captures via DM-nucleon and DM-DM scatterings, the energy dissipation via DM annihilation, and the heat exchange between DM and solar nuclei. We examine the DM temperature evolution and demonstrate that the DM temperature can be higher than the core temperature of the Sun if the DM-nucleon cross section is sufficien…
We explore the electron neutrino signals from light dark matter (DM) annihilation in the Sun for the large liquid scintillator detector JUNO. In terms of the spectrum features of three typical DM annihilation channels $χχ\rightarrow ν\barν,τ^+ τ^-, b \bar{b}$, we take two sets of selection conditions to calculate the expected signals and atmospheric neutrino backgrounds based on the Monte Carlo simulation data. Then the JUNO sensitivities to the spin independent DM-nucleon and spin dependent DM-proton cross sections are presented. It is found that the JUNO projected sensitivities are much bett…
We show the existence of the strong inverse correlation between the temporal variations of the toroidal component of the magnetic field in the solar tachocline (the bottom of the convective zone) and the Earth magnetic field (the Y-component). The possibility that the hypothetical solar axions, which can transform into photons in external electric or magnetic fields (the inverse Primakoff effect), can be the instrument by which the magnetic field of the Sun convective zone modulates the magnetic field of the Earth is considered. We propose the axion mechanism of Sun luminosity and "solar dynam…
Super-Kamiokande (SK) can search for weakly interacting massive particles (WIMPs) by detecting neutrinos produced from WIMP annihilations occurring inside the Sun. In this analysis, we include neutrino events with interaction vertices in the detector in addition to upward-going muons produced in the surrounding rock. Compared to the previous result, which used the upward-going muons only, the signal acceptances for light (few-GeV/$c^2$ $\sim$ 200-GeV/$c^2$) WIMPs are significantly increased. We fit 3903 days of SK data to search for the contribution of neutrinos from WIMP annihilation in the S…
We used a consistent and robust solar model to obtain upper limits placed by neutrino telescopes, such as Ice- Cube and Super-Kamiokande, on the Dark Matter-nucleon scattering cross-section, for a general model of Dark Matter with a velocity dependent (p-wave) thermally averaged cross-section. In this picture, the Boltzmann equation for the Dark Matter abundance is numerically solved satisfying the Dark Matter density measured from the Cosmic Microwave Background (CMB). We show that for lower cross-sections and higher masses, the Dark Matter annihilation rate drops sharply, resulting in upper …
We study indirect detection signals from solar annihilation of dark matter (DM) particles into light right-handed (RH) neutrinos with a mass in a $1-5$ GeV range. These RH neutrinos can have a sufficiently long lifetime to allow them to decay outside the Sun and their delayed decays can result in a signal in gamma rays from the otherwise `dark' solar direction, and also a neutrino signal that is not suppressed by the interactions with solar medium. We find that the latest Fermi-LAT and IceCube results place limits on the gamma ray and neutrino signals, respectively. Combined photon and neutrin…
The next generation of dark matter (DM) direct detection experiments and neutrino telescopes will probe large swaths of dark matter parameter space. In order to interpret the signals in these experiments, it is necessary to have good models of both the halo DM streaming through the solar system and the population of DM bound to the solar system. In this paper, the first in a series of three on DM in the solar system, we present simulations of orbits of DM bound to the solar system by solar capture in a toy solar system consisting of only the Sun and Jupiter, assuming that DM consists of a sing…
