arXiv subjects

Ruitian Li

Publications and source records attributed to Ruitian Li.

10 recordsLinked to original sources

arXiv2026

A Spatially Resolved HI Survey of Seyfert Galaxies: the Role of AGN Feedback in Shaping Atomic Gas Reservoirs

Active galactic nucleus (AGN) feedback is a key ingredient in galaxy evolution, yet its impact on the cold atomic gas reservoir -- the neutral hydrogen (HI) phase -- remains poorly constrained. We present the most extensive spatially resolved HI 21-cm survey of Seyfert AGN hosts to date, based on observations with the Giant Metrewave Radio Telescope (GMRT). Our high-resolution HI maps of eight Seyfert galaxies reveal detailed kinematics and surface density distributions of their atomic gas disks. We find that AGN-host galaxies exhibit a slightly shallower HI mass-size relation than the canonical relation or the SIMBA simulation predictions; however, the measured slope remains consistent with the canonical value within $2σ$ uncertainties. This result suggests that AGN feedback does not significantly disrupt the global extent or large-scale structure of atomic gas reservoirs. To investigate the internal HI kinematics in greater detail, we perform a 3D kinematic forward modeling of the HI disk in UGC 4503. Our analysis reveals an elevated intrinsic velocity dispersion of $σ= 14.9^{+6.1}_{-3.8}$ km/s and a reduced level of rotational support, with $V/σ= 14.28_{-4.17}^{+4.97}$, compared to large-sample star-forming spirals. These kinematic signatures, together with localized residuals in the velocity field, indicate that AGN-driven outflows or jets may inject or indirectly affect the turbulence in the atomic gas disk, potentially regulating the cold gas reservoir. Future GMRT observations, combined with optical integral-field spectroscopy from MaNGA, will enable quantitative constraints on the role of AGN feedback in regulating star formation efficiency across a larger and more representative galaxy sample.

astro-ph.GA↗

arXiv2026

Theoretical study of $f_0(980)$, $a_0(980)$ and $Ξ(1/2^-)$ in the process $Ξ_c^+ \to Σ^+K^+K^-$

We employed the chiral unitarity approach to investigate the decay process $Ξ_c^+ \to Σ^+K^+K^-$, by considering that the low lying nucleon resonance $Ξ(1/2^-)$ and the low lying scalar meson $f_0(980)$ and $a_0(980)$ that could be dynamically generated through $S$-wave pseudoscalar meson-octet baryon and the $S$-wave pseudoscalar meson-pseudoscalar meson interactions, respectively. In the invariant mass distributions of $Σ^+K^-$ and $K^+K^-$, we observe a distinct peak structure associated with the resonant state $Ξ(1/2^-)$ and a bit enhancement near the $K^+K^-$ threshold that is corresponding to the mesons $f_0(980)$ and $a_0(980)$, respectively. Consequently, we recommend more precise experimental measurements of this process in the future.

hep-ph↗

arXiv2026

Searching for ALP Lepton Flavor Violation via ALP Decays at the LHC

In the ALP model, lepton flavor violation (LFV) can arise from off-diagonal ALP-lepton couplings ($g_{a\ell_i\ell_j}$), which are absent in the Standard Model. We focus on ALP production via gluon fusion ($pp \to a$) at the Large Hadron Collider (LHC), which dominates the ALP mass range of 5-1000 GeV due to its high cross section and manageable backgrounds. We are interested in the decay of an axion into an electron and a muon, two oppositely charged leptons of different flavors. After background suppression, we obtain the sensitivity to ALP in this mass range, finding significantly improved limits for $5 < m_a < 1000$ GeV, where SM backgrounds are suppressed. Our research is complementary with relevant studies.

hep-ph↗

arXiv2025

Theoretical study of the $N(1535)$ in the process $Λ_c^+\to nπ^+π^0$

We have investigated the $Λ_c^+\to nπ^+π^0$ decay process using the chiral unitary approach, by considering that the nucleon resonance $N(1535)$ could be dynamically generated through $S$-wave pseudoscalar meson-octet baryon interactions. In the invariant mass distributions of $π^0n$ and $π^+n$, we observe a distinct peak structure associated with the resonance states $N(1535)^0$ and $N(1535)^+$, respectively. Our results suggest that the $Λ_c^+\to nπ^+π^0$ process can be utilized to probe the properties of the nucleon $N(1535)$, and therefore, we encourage more precise experimental measurements of this process in the future.

hep-ph↗

arXiv2025

Solving two and three-body systems with deep neural networks

We develop a new method for solving two- and three-body bound state problems using unsupervised machine learning techniques. We use a deep neural network to calculate both simple and realistic potentials, obtaining the properties of the deuteron and triton bound states for the chiral effective field theory NN potential. Our results provide significant accuracy with no prior assumptions about the behaviour of the wave function. This neural network technique, which extends from two-body to three-body, may provide insight into potential solutions to the nuclear and hadronic many-body problems.

hep-ph↗

arXiv2024

The Theoretical Study of $p\bar{p}\to\barΛΣη$ Reaction

We study the production of hyperon resonances in the $p\bar{p}\to\barΛΣη$ reaction within an effective Lagrangian approach. The model includes the production of $Σ(1750)$ and $Λ(1670)$ in the intermediate state excited by the $K$ and $K^*$ meson exchanges between the initial proton and antiproton. Due to the large coupling of $Σ(1750)Ση$ vertex, $Σ(1750)$ is found a significant contribution near the threshold in this reaction. We provide total and differential cross section predictions for the reation and discuss the possible influence of $Σ(1750)Ση$ vertex coupling and model parameters, which will be useful in future experimental studies. This reaction can provide a platform for studying the features of $Σ(1750)$ resonance, especially the coupling to $Ση$ channel.

hep-ph↗

arXiv2024

Exploring the molecular scenario of X(4160)

In this work, we investigate the decays of meson $X(4160)$ in the molecular frame. By using an effective lagrangian approach, we calculate the widths of $X(4160)\to J/ψϕ$, $D^*\bar{D}^*$, $D^*\bar{D}$ and $D\bar{D}$ through the triangle loop mechanism in the molecular scenario. Based on the compositeness condition, the coupling between $X(4160)$ and the $D_s^*\bar{D}_s^*$ molecular state is determined. The other coupling constants used are determined phenomenologically. The calculation of the decay widths shows that the $D^*\bar{D}^*$ decay mode has a larger branching ratio. These predictions can be seen as a test for the charmonium assignment of $X(4160)$.

hep-ph↗

arXiv2024

The Theoretical Study of $π^+p\to pa_0^+ϕ$ Reaction

We study the production of hyperon resonances in the $π^+p\to pa_0^+ϕ$ reaction within an effective Lagrangian approach. The model includes the production of $Δ(1940)$ and $Δ(1920)$ in the intermediate state excited by the $ρ$ and $p$ exchanges between the initial proton and $π$ meson. Due to the large contribution of $ρ$ exchange in $Δ(1940)$ production, $Δ(1940)$ is found a significant contribution near the threshold in this reaction. We provide total and differential cross section predictions for the reation and discuss the possible influence of model parameters, off-shell effects and branching ratios for $Δ(1940)\to pa_0$ and $Δ(1920)\to pa_0$ decays, which will be useful in future experimental studies. This reaction can provide a platform for studying the features of $Δ(1940)$ resonance, especially the coupling to $pa_0$ channel.

hep-ph↗

arXiv2024

Theoretical study of the $B^+\to D^-D_s^{+}π^+$ reaction

Prompted by the recent discoveries of $T_{c\bar{s}0}(2900)^{++}$ in the $D_s^+π^+$ invariant mass distribution of $B^+\to D^-D_s^+π^+$ process, we present a model that hopes to help us investigate the nature of $T_{c\bar{s}0}(2900)^{++}$ by reproducing the mass distribution of $D^-π^+, D_s^+π^+$ and $D^-D_s^+$ in $B^+ \to D^-D_s^+π^+$ decays. The structure of the triangular singularity peak generated from the $χ_{c1}D^{*+}K^{*+}$ loop near the $D^{*+}K^{*+}$ threshold is considered in our model may be the experimentally discovered resonance-like state structure $T_{c\bar{s}0}(2900)^{++}$. In addition, we employ a coupled-channel approach to describe the dominant contribution of the $Dπ$ $S\text{-wave}$ amplitude, and also consider other excitations. Our model provides a well fit to the invariant mass distributions of $D^-π^+, D_s^+π^+$ and $D^-D_s^+$ simultaneously.

hep-ph↗

arXiv2023

The theoretical study of $D_s^+\toπ^+π^0π^0$

Inspired by recent BESIII's amplitude analysis on $D_s^+\toπ^+π^0π^0$, we develop a model based on the chiral unitary approach to discribe the $D_s^+\toπ^+π^0π^0$ decay, where $D_s^+$ decays into a $π^+$ and a quark-antiquark pair through weak decay of charm quark. The interaction of pseudoscalar mesons produced by the hadronization of quark-antiquark pair will lead to dynamically generated $f_0(980)$. The dominant amplitudes from resonances $f_0(1370)$ and $f_2(1270)$ in BESIII fit are also included in our model. In addition to above contributions, to obtain a good fit we also add a amplitude from resonance $f_2(1430)$ to our model. Our model fits well $M_{π^0π^0}$ and $M_{π^+π^0}$ invariant mass distributions simultaneously.

hep-ph↗