arXiv subjects

Yen-Hsun Lin

Publications and source records attributed to Yen-Hsun Lin.

At least 19 recordsLinked to original sources

arXiv2026

Circumstellar Medium of Supernovae as New Probes for Feebly-interacting Particles

We propose a novel strategy to probe feebly-interacting particles (FIPs) by exploiting the dense, confined circumstellar medium (CSM) surrounding core-collapse supernovae (CCSNe). FIPs produced in the proto-neutron star can deposit substantial visible energy into the CSM via decay prior to the shock breakout from the progenitor star. This energy injection heats and ionizes the CSM, establishing a FIP-induced photosphere that generates distinctive precursor blackbody emission. Using early-time observations of SN 2023ixf, we translate the non-detection of excessive precursor luminosity into stringent new constraints on MeV-scale dark photons as an exemplary model. Our results significantly extend existing CCSN bounds and exclude previously unexplored regions of parameter space. We further demonstrate that the FIP-induced dust sublimation offers robust diagnostics for future Galactic SNe, opening a new avenue to explore the dark sector.

hep-ph↗

arXiv2025

Mapping the evolution of supernova-neutrino-boosted dark matter within the Milky Way

Supernova-neutrino-boosted dark matter (SN$\nu$ BDM) has emerged as a promising portal for probing sub-GeV dark matter. In this work, we investigate the behavior of BDM signatures originating from core-collapse supernovae within the Milky Way (MW) over the past one hundred thousand years, examining both their temporal evolution and present-day spatial distributions. We show that while the MW BDM signature is approximately diffuse in the nonrelativistic regime, it exhibits significant temporal variation and spatial localization when the BDM is relativistic. Importantly, we compare these local MW signatures with the previously proposed diffuse SN$\nu$ BDM (DBDM), which arises from the accumulated flux of all past supernovae in the Universe [Y.-H. Lin and M.-R. Wu, Phys. Rev. Lett. 133, 111004 (2024)]. In the nonrelativistic limit, DBDM consistently dominates over the local diffuse MW BDM signature. Only when the MW BDM becomes ultrarelativistic and transitions into a transient, highly-localized signal can it potentially surpass the DBDM background. This work thus reinforces the importance of DBDM for SN$\nu$ BDM searches until the next galactic SN offers new opportunities.

hep-ph↗

arXiv2024

Signatures of afterglows from light dark matter boosted by supernova neutrinos in current and future large underground detectors

Supernova neutrino boosted dark matter (SN$ν$ BDM) and its afterglow effect have been shown to be a promising signature for beyond Standard Model (bSM) physics. The time-evolution feature of SN$ν$ BDM allows for %the possibly direct inference of DM mass $m_χ$, and results in significant background suppression with improving sensitivity. This paper extends the earlier study and provides a general framework for computing the SN$ν$ BDM fluxes for a supernova that occurs at any location in our galaxy. A bSM $U(1)_{L_μ-L_τ}$ model with its gauge boson coupling to both DM and the second and third generation of leptons is considered, which allows for both DM-$ν$ and DM-$e$ interactions. Detailed analysis of the temporal profile, angular distribution, and energy spectrum of the SN$ν$ BDM are performed. Unique signatures in SN$ν$ BDM allowing extraction of $m_χ$ and detail features that contain information of the underlying interaction type are discussed. Expected sensitivities on the above new physics model from Super-Kamiokande, Hyper-Kamiokande, and DUNE detections of BDM events induced by the next galactic SN are derived and compared with the existing bounds.

hep-ph↗

arXiv2024

Searching for Afterglow: Light Dark Matter Boosted by Supernova Neutrinos

A novel analysis is performed, incorporating time-of-flight (TOF) information to study the interactions of dark matter (DM) with standard model particles. After supernova (SN) explosions, DM with mass $m_χ\lesssim\mathcal{O}({\rm MeV})$ in the halo can be boosted by SN neutrinos (SN$ν$) to relativistic speed. The SN$ν$ boosted DM (BDM) arrives on Earth with TOF which depends only on $m_χ$ and is independent of the cross section. These BDMs can interact with detector targets in low-background experiments and manifest as afterglow events after the arrival of SN$ν$. The characteristic TOF spectra of the BDM events can lead to large background suppression and unique determination of $m_χ$. New cross section constraints on $\sqrt{σ_{χe} σ_{χν}}$ are derived from SN1987a in the Large Magellanic Cloud with data from the Kamiokande and Super-Kamiokande experiments. Potential sensitivities for the next galactic SN with Hyper-Kamiokande are projected. This analysis extends the existing bounds on $\sqrt{σ_{χe}σ_{χν}}$ over a broad range of $r_χ=σ_{χν}/σ_{χe}$. In particular, the improvement is by 1-3 orders of magnitude for $m_χ<\mathcal{O}(100\,{\rm keV})$ for $σ_{χe}\simσ_{χν}$. Prospects of exploiting TOF information in other astrophysical systems to probe exotic physics with other DM candidates are discussed.

hep-ph↗

arXiv2024

Supernova-Neutrino-Boosted Dark Matter from All Galaxies

It has been recently proposed that the boosted dark matter (BDM) by supernova neutrinos (SN$\nu$) from SN1987a or from the next Galactic supernova (SN) can serve as a novel component to probe nonvanishing interaction between dark matter (DM) and the standard model leptons [Y.-H. Lin et al., Phys. Rev. Lett 130, 111002 (2023) and Y.-H. Lin et al., Phys. Rev. D 108, 083013 (2023)]. In this Letter, we extend this concept and evaluate the present-day diffuse flux of SN$\nu$ BDM originated from all galaxies at higher redshifts. We show that by considering this diffuse BDM (DBDM) component, the best sensitivity on the product of the energy-independent DM-$\nu$ and DM-electron cross sections, $\sqrt{\sigma_{\chi\nu}\sigma_{\chi e}}\simeq \mathcal{O}(10^{-37})$ cm$^2$ for sub-MeV DM, can be obtained with large-size neutrino experiments such as Super-Kamiokande or Hyper-Kamiokande, surpassing the estimated SN$\nu$ BDM bound from SN1987a. We also examine the impact due to the presence of DM spikes around the supermassive black holes in galaxies on SN$\nu$ BDM and DBDM. Our results suggest that both the DBDM and the SN$\nu$ BDM probes are robust to the uncertain properties of DM spikes, unless the next Galactic SN happens to occur at a location extremely close to or right behind the Galactic Center along the SN line of sight.

hep-ph↗

arXiv2023

Compact Dark Objects in Neutron Star Mergers

We estimate the long-lasting gravitational wave (GW) emission of compact dark objects following a binary neutron-star (NS) merger. We consider compact dark objects, which initially reside in the centers of NSs and which may consist of self-interacting dark matter (DM). By approximating the compact dark objects as test particles, we model the merging of NS binaries hosting DM components with three-dimensional relativistic simulations. Our simulation results suggest that the DM components remain gravitationally bound and orbit inside the merger remnant with orbital separations of typically a few km. The subsequent orbital motion of the DM components generates a GW signal with frequencies in the range of a few kHz. When considering a range of different binary masses and high-density equations of state (EoS), we find that the GW frequency of the orbiting DM components scales with the compactness of NSs. Similarly, we find relations between the DM GW frequency and the dominant postmerger GW frequency of the stellar fluid or the tidal deformability, which quantifies EoS effects during the binary inspiral. Hence, a measurement of these quantities can be used to specify the frequency range of the GW emission by DM. Under the assumption that GW back reaction is the only relevant dissipative process, the GW signal may last between seconds and years depending on the mass of the DM component. We estimate the detectability of the GW signals and find that DM components in NS mergers may only be detectable with existing and projected GW instruments if the dark objects are as massive as about 0.01 to 0.1 M_sun. We emphasize that the GW emission is limited by the lifetime of the remnant. A forming black hole will immediately swallow the DM objects because their orbits are smaller than the innermost stable circular orbit of the black hole.

astro-ph.HE↗

arXiv2021

Exploring dark sector parameters in light of neutron star temperatures

Using neutron stars (NS) as a dark matter (DM) probe has gained broad attention recently, either from heating due to DM annihilation or its stability under the presence of DM. In this work, we investigate spin-$1/2$ fermionic DM $χ$ charged under the $U(1)_{X}$ in the dark sector. The massive gauge boson $V$ of $U(1)_{X}$ gauge group can be produced in NS via DM annihilation. The produced gauge boson can decay into Standard Model (SM) particles before it exits the NS, despite its tiny couplings to SM particles. Thus, we perform a systematic study on $χ\barχ\to2V\to4{\rm SM}$ as a new heating mechanism for NS in addition to $χ\barχ\to2{\rm SM}$ and kinetic heating from DM-baryon scattering. The self-trapping due to $χV$ scattering is also considered. We assume the general framework that both kinetic and mass mixing terms between $V$ and SM gauge bosons are present. This allows both vector and axial-vector couplings between $V$ and SM fermions even for $m_V\ll m_Z$. Notably, the contribution from axial-vector coupling is not negligible when particles scatter relativistically. We point out that the above approaches to DM-induced NS heating are not yet adopted in recent analyses. Detectabilities of the aforementioned effects to the NS surface temperature by the future telescopes are discussed as well.

hep-ph↗

arXiv2020

Analysis on the black hole formations inside old neutron stars by isospin-violating dark matter with self-interaction

Fermionic dark matter (DM) with attractive self-interaction is possible to form black holes (BH) inside the Gyr-old neutron stars (NS). Therefore by observing such NS corresponding to their adjacent DM environments can place bounds on DM properties, eg. DM-baryon cross section $σ_{χb}$, DM mass $m_χ$, dark coupling $α_χ$ and mediator mass $m_ϕ$. In case of isospin violation, DM couples to neutron and proton in different strengths. Even NS is composed of protons roughly one to two percent of the total baryons, the contribution from protons to the DM capture rate could be drastically changed in the presence of isospin violation. We demonstrate that this effect can be important in certain cases. On the other hand, DM-forming BH inside the star is subject to many criteria and the underlying dynamics is rich with interesting features. We also systematically review the relevant physics based on the virial equation. Moreover, an accompanied python package \texttt{dm2nsbh} to realize the mechanism is also released on the github for other relevant research.

hep-ph↗

arXiv2018

Reheating neutron stars with the annihilation of self-interacting dark matter

Compact stellar objects such as neutron stars (NS) are ideal places for capturing dark matter (DM) particles. We study the effect of self-interacting DM (SIDM) captured by nearby NS that can reheat it to an appreciated surface temperature through absorbing the energy released due to DM annihilation. When DM-nucleon cross section $σ_{χn}$ is small enough, DM self-interaction will take over the capture process and make the number of captured DM particles increased as well as the DM annihilation rate. The corresponding NS surface temperature resulted from DM self-interaction is about hundreds of Kelvin and is potentially detectable by the future infrared telescopes. Such observations could act as the complementary probe on DM properties to the current DM direct searches.

hep-ph↗

arXiv2018

The 17 MeV Anomaly in Beryllium Decays and $U(1)$ Portal to Dark Matter

The experiment of Krasznahorkay \textit{et al} observed the transition of a $\rm{^{8}Be}$ excited state to its ground state and accompanied by an emission of $e^{+}e^{-}$ pair with 17 MeV invariant mass. This 6.8$σ$ anomaly can be fitted by a new light gauge boson. We consider the new particle as a $U(1)$ gauge boson, $Z'$, which plays as a portal linking dark sector and visible sector. In particular, we study the new $U(1)$ gauge symmetry as a hidden or non-hidden group separately. The generic hidden $U(1)$ model, referred to as dark $Z$ model, is excluded by imposing various experimental constraints. On the other hand, a non-hidden $Z'$ is allowed due to additional interactions between $Z'$ and Standard Model fermions. We also study the implication of the dark matter direct search on such a scenario. We found the search for the DM-nucleon scattering excludes the range of DM mass above 500 MeV. However, the DM-electron scattering for MeV-scale DM is still allowed by current constraints for non-hidden $U(1)$ models. It is possible to test the underlying $U(1)$ portal model by the future Si and Ge detectors with $5e^{-}$ threshold charges.

hep-ph↗

arXiv2018

On the evolution process of two-component dark matter in the Sun

We introduce dark matter (DM) evolution process in the Sun under a two-component DM (2DM) scenario. Both DM species $χ$ and $ξ$ with masses heavier than 1 GeV are considered. In this picture, both species could be captured by the Sun through DM-nucleus scattering and DM self-scatterings, e.g. $χχ$ and $ξξ$ collisions. In addition, the heterogeneous self-scattering due to $χ$ and $ξ$ collision is essentially possible in any 2DM models. This new introduced scattering naturally weaves the evolution processes of the two DM species that was assumed to evolve independently. Moreover, the heterogeneous self-scattering enhances the number of DM being captured in the Sun mutually. This effect significantly exists in a broad range of DM mass spectrum. We have studied this phenomena and its implication for the solar-captured DM annihilation rate. It would be crucial to the DM indirect detection when the two masses are close. General formalism of the 2DM evolution in the Sun as well as its kinematics are studied.

hep-ph↗

arXiv2017

Study of $B^\pm_c \to (D^0 K^\pm, D^0 π^\pm)$ decays

LHCb observes the $B^+_c \to D^0 K^+$ decay with $R_{D^0 K} = f_c/f_u \times {\cal B}(B^+_c \to D^0 K^+)=(9.3^{+2.8}_{-2.5} \pm 0.6)\times 10^{-7}$. The corresponding branching ratio (BR) of the decay can be estimated as ${\cal B}(B^+_c \to D^0 K^+) \approx (10.01 \pm 3.40)\times 10^{-5}$; however, the theoretical estimates vary from $\sim 10^{-7}$ to $\sim 5\times 10^{-5}$. We phenomenologically investigate the $B^+_c \to (D^0 K^+, D^0 π^+)$ decays through the analysis of $B\to KK$, $B^+_u\to D^+ K^0$, and $B_d \to D^-_s K^+$. With the form factor of $f^{B_c D}_0\approx 0.2$, it is found that the tree-annihilation contribution dominates the $B^+_c \to D^0 K^+$ decay, and when ${\cal B}(B^+_u \to D^+ K^0) \approx (1-3.1) \times 10^{-7}$ is required, we obtain ${\cal B}(B^+_c \to D^0 K^+)\approx (4.4- 9) \times 10^{-5}$, and the magnitude of CP asymmetry is lower than approximately $10\%$. Although the $B^+_c \to D^0 π^+$ decay is dominated by the tree-transition effect, the tree-annihilation also makes an important contribution, where its effect could be around $70\%$ of the tree-transition. It is found that when ${\cal B}(B^+_c \to D^0 K^+)\approx (4.4- 9) \times 10^{-5}$ is taken, the BR and CP asymmetry for $B^+_c \to D^0 π^+$ with the common values of parameters can be ${\cal B}(B^+_c \to D^0 π^+)\approx (4.9-8)\times 10^{-6}$ and of the order of one, respectively. Moreover, we conclude ${\cal B}(B^+_c \to D^+ K^0)\approx {\cal B}(B^+_c \to D^0 K^+)$, and the BRs for $B^+_c \to K^+ \bar K^0$ and $B^+_c \to J/Ψπ^+$ are $(6.99 \pm 1.34) \times 10^{-7}$ and $(7.7 \pm 1.1)\times 10^{-4}$, respectively.

hep-ph↗

arXiv2015

Neutrino Physics with JUNO

The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose underground liquid scintillator detector, was proposed with the determination of the neutrino mass hierarchy as a primary physics goal. It is also capable of observing neutrinos from terrestrial and extra-terrestrial sources, including supernova burst neutrinos, diffuse supernova neutrino background, geoneutrinos, atmospheric neutrinos, solar neutrinos, as well as exotic searches such as nucleon decays, dark matter, sterile neutrinos, etc. We present the physics motivations and the anticipated performance of the JUNO detector for various proposed measurements. By detecting reactor antineutrinos from two power plants at 53-km distance, JUNO will determine the neutrino mass hierarchy at a 3-4 sigma significance with six years of running. The measurement of antineutrino spectrum will also lead to the precise determination of three out of the six oscillation parameters to an accuracy of better than 1\%. Neutrino burst from a typical core-collapse supernova at 10 kpc would lead to ~5000 inverse-beta-decay events and ~2000 all-flavor neutrino-proton elastic scattering events in JUNO. Detection of DSNB would provide valuable information on the cosmic star-formation rate and the average core-collapsed neutrino energy spectrum. Geo-neutrinos can be detected in JUNO with a rate of ~400 events per year, significantly improving the statistics of existing geoneutrino samples. The JUNO detector is sensitive to several exotic searches, e.g. proton decay via the $p\to K^++\barν$ decay channel. The JUNO detector will provide a unique facility to address many outstanding crucial questions in particle and astrophysics. It holds the great potential for further advancing our quest to understanding the fundamental properties of neutrinos, one of the building blocks of our Universe.

physics.ins-det↗

arXiv2015

Complementary Test of the Dark Matter Self-Interaction by Direct and Indirect Detections

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 reachable by direct detections. Those parameter ranges are either the region with a very small $m_χ$ or the region opened up due to isospin violations.

hep-ph↗

arXiv2015

Thermal transport of the solar captured dark matter and its impact on the indirect dark matter search

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 sufficiently small such that the energy flow due to DM self-interaction becomes relatively important. We argue that the correct DM temperature should be used for accurately predicting the DM annihilation rate, which is relevant to the DM indirect detection.

hep-ph↗

arXiv2014

The dark matter self-interaction and its impact on the critical mass for dark matter evaporations inside the sun

We study the capture, annihilation and evaporation of dark matter (DM) inside the Sun. It has been shown that the DM self-interaction can increase the DM number inside the Sun. We demonstrate that this enhancement becomes more significant in the regime of small DM mass, given a fixed DM self-interaction cross section. This leads to the enhancement of neutrino flux from DM annihilation. On the other hand, for DM mass as low as as a few GeVs, not only the DM-nuclei scatterings can cause the DM evaporation, DM self-interaction also provides non-negligible contributions to this effect. Consequently, the critical mass for DM evaporation (typically 3 ~ 4 GeV without the DM self-interaction) can be slightly increased. We discuss the prospect of detecting DM self-interaction in IceCube- PINGU using the annihilation channels $χχ\rightarrowν\barν,\:τ^{-}τ^{+}$ as examples. The PINGU sensitivities to DM self-interaction cross section $σ_{χχ}$ are estimated for track and cascade events.

hep-ph↗

arXiv2014

Probing Dark Matter Self-Interaction in the Sun with IceCube-PINGU

We study the capture, annihilation and evaporation of dark matter (DM) inside the Sun. It has been shown that the DM self-interaction can increase the DM number inside the Sun. We demonstrate that this enhancement becomes more significant in the regime of small DM mass, given a fixed DM self-interaction cross section. This leads to the enhancement of neutrino flux from DM annihilation. On the other hand, for DM mass as low as a few GeVs, not only the DM-nuclei scatterings can cause the DM evaporation, DM self-interaction also provides non-negligible contributions to this effect. Consequently, the critical mass for DM evaporation (typically 3 $\sim$ 4 GeV without the DM self-interaction) can be slightly increased. We discuss the prospect of detecting DM self-interaction in IceCube-PINGU using the annihilation channels $χχ\rightarrow τ^{+}τ^{-}, ν\barν$ as examples. The PINGU sensitivities to DM self-interaction cross section $σ_{χχ}$ are estimated for track and cascade events.

hep-ph↗

arXiv2014

Probing the coupling of heavy dark matter to nucleons by detecting neutrino signature from the Earth's core

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 signature from galactic halo can only probe DM annihilation cross sections. We present neutrino event rates in IceCube and KM3NeT arising from the neutrino flux produced by annihilation of Earth-captured DM heavier than $10^{4}$ GeV. The IceCube and KM3NeT sensitivities to spin independent DM-proton scattering cross section $σ_{χp}$ in this mass range are presented for both isospin symmetric and isospin violating cases.

hep-ph↗