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We have performed calculations for the nonleptonic Ξb-→π-Ξc0(2790)J=12 and Ξb-→π-Ξc0(2815)J=32 decays and the same reactions replacing the π- by a Ds-. At the same time we have also evaluated the semileptonic rates for Ξb-→ν¯llΞc0(2790) and Ξb-→ν¯llΞc0(2815). We look at the reactions from the perspective that the Ξc0(2790) and Ξc0(2815) resonances are dynamically generated from the pseudoscalar–baryon and vector–baryon interactions. We evaluate ratios of the rates of these reactions and make predictions that can be tested in future experiments. We also find that the results are rather sensitive to the coupling of the Ξc∗ resonances to the D∗Σ and D∗Λ components.

We discuss the mass splittings for the S-wave triply heavy pentaquark states with the \\[QQQqq\\]\\[(Q=b,c;q=u,d,s)\\] configuration which is a mirror structure of \\[QQqqq\\]. The latter configuration is related with the nature of \\[P_c(4380)\\] observed by the LHCb Collaboration. The considered pentaquark masses are estimated with a simple method. One finds that such states are probably not narrow even if they do exist. This leaves room for molecule interpretation for a state around the low-lying threshold of a doubly heavy baryon and a heavy-light meson, e.g. \\[ _ccD\\], if it were observed. As a by product, we conjecture that upper limits for the masses of the conventional triply heavy baryons can be determined by the masses of the conventional doubly heavy baryons.

The Theta super(+) pentaquark baryon was searched for via the pi super(-) p arrow right K super(-) X reaction at J-PARC. pi super(-) meson beams were irradiated on the liquid hydrogen target with the beam momentum of 1.92 GeV/c. In the missing mass spectrum, no peak structure corresponding to Theta super(+) mass was observed. The preliminary upper limit of the differential cross section averaged over the scattering angle of 2 degree to 15 degree at the laboratory frame was less than 0.3 mu b/sr at the 90 % confidence level in the missing mass region over 1.51 to 1.55 GeV/c super(2).

We present updated constraints on cosmological parameters in a 12-parameter model, extending the standard six-parameter ΛCDM by including dynamical dark energy (DE; w 0, w a ), the sum of neutrino masses (∑m ν ), the effective number of non-photon radiation species (N eff), the lensing amplitude scaling (A lens), and the running of the scalar spectral index (α s ). For cosmic wave background (CMB) data, we use the Planck Public Release (PR) 4 (2020) HiLLiPoP and LoLLiPoP likelihoods, Planck PR4+Atacama Cosmology Telescope (ACT) DR6 lensing, and Planck 2018 low-ℓ TT likelihoods, along with DESI DR1 baryon acoustic oscillations (BAO) and Pantheon+ and DESY5 uncalibrated Type Ia supernovae (SNe) likelihoods. Key findings are the following: (i) Contrary to DESI results, CMB+BAO+Pantheon+ data include a cosmological constant within 2σ, while CMB+BAO+DESY5 excludes it at over 2σ, indicating the dynamical nature of DE is not yet robust. Potential systematics in the DESY5 sample may drive this exclusion. (ii) Some data combinations show a 1σ+ detection of nonzero ∑m ν , indicating possible future detection. We also provide a robust upper bound of ∑m ν ≲ 0.3 eV (95% confidence limit (CL)). (iii) With CMB+BAO+SNe, A lens = 1 is included at 2σ (albeit not at 1σ), indicating no significant lensing anomaly in this extended cosmology with Planck PR4 likelihoods. (iv) The Hubble tension persists at 3.2 to 3.9σ, suggesting these simple extensions do not resolve it. (v) The S 8 tension with Dark Energy Survey Year 3 weak lensing is reduced to 1.4σ, likely due to additional parameters and the Planck PR4 likelihoods.

It was recently demonstrated [1] that the meson-baryon rescattering in the final state has a major impact on the magnitude and structure of the πΣ mass distributions observed in the γp → K+πΣ photoproduction. We discuss briefly several aspects of this work emphasizing the model dependence of the meson-baryon amplitudes, used to represent the final-state interaction, and the role of the adopted photoproduction mechanism.

Abstract In recent decades, the spectroscopy of singly heavy baryons has made significant progress, with many excited states observed experimentally. Among the various theoretical approaches used to study their properties, the QCD sum rule method has been widely applied. In this paper, we review QCD sum rule studies of singly heavy baryons, with particular emphasis on our systematic investigations ofP-wave states over the past ten years using QCD sum rules and light-cone sum rules within the framework of heavy quark effective theory. These studies provide plausible interpretations for many observed excited heavy baryons, including theΛ_(c)(2595)⁺,Λ_(c)(2625)⁺,Ξ_(c)(2790)^(0/+),Ξ_(c)(2815)^(0/+),Σ_(c)(2800)⁰,Ξ_(c)(2882)⁰,Ξ_(c)(2923)⁰,Ξ_(c)(2939)⁰,Ξ_(c)(2965)⁰,Ω_(c)(3000)⁰,Ω_(c)(3050)⁰,Ω_(c)(3066)⁰,Ω_(c)(3090)⁰,Ω_(c)(3119)⁰,Λ_(b)(5912)⁰,Λ_(b)(5920)⁰,Ξ_(b)(6087)⁰,Ξ_(b)(6095)⁰/Ξ_(b)(6100)⁻,Σ_(b)(6097)^(±),Ξ_(b)(6227)⁻,Ω_(b)(6316)⁻,Ω_(b)(6330)⁻,Ω_(b)(6340)⁻, andΩ_(b)(6350)⁻. While the absolute masses extracted from QCD sum rules may have sizable systematic uncertainties, the relative mass splittings and qualitative decay patterns are generally more robust and thus provide useful guidance for phenomenological assignments and future experimental searches. We also predict a number of yet-unobservedP-wave singly heavy baryons, many of which are expected to have relatively narrow decay widths and are therefore promising for experimental observation. More broadly, the study of singly heavy baryons is closely related to two fundamental questions: “What is the shortest possible lifetime of an observable particle” and “How can one generally describe approximate (flavor) symmetries”.

The recent results from the first-year baryon acoustic oscillations (BAO) data released by the Dark Energy Spectroscopic Instrument (DESI), combined with cosmic microwave background (CMB) and Type Ia supernova (SN) data, have shown a detection of significant deviation from a cosmological constant for dark energy. In this work, we utilize the latest DESI BAO data in combination with the SN data from the full 5 yr observations of the Dark Energy Survey and the CMB data from the Planck satellite to explore potential interactions between dark energy and dark matter. We consider four typical forms of the interaction term Q. Our findings suggest that interacting dark energy (IDE) models with Q ∝ ρ de support the presence of an interaction where dark energy decays into dark matter. Specifically, the deviation from ΛCDM for the IDE model with Q = β H 0 ρ de reaches the 3σ level. These models yield a lower value of Akaike information criterion than the ΛCDM model, indicating a preference for these IDE models based on the current observational data. For IDE models with Q ∝ ρ c, the existence of interaction depends on the form of the proportionality coefficient Γ. The IDE model with Q = β H ρ c yields β = 0.0003 ± 0.0011, which essentially does not support the presence of the interaction. In general, whether the observational data support the existence of interaction is closely related to the model. Our analysis helps to elucidate which type of IDE model can better explain the current observational data.

We obtain constraints in a 12 parameter cosmological model using the recent Dark Energy Spectroscopic Instrument Data Release (DR) 2 Baryon Acoustic Oscillations (BAO) data, combined with cosmic microwave background (CMB) power spectra (Planck Public Release, PR, 4) and lensing (Planck PR4 + Atacama Cosmology Telescope DR 6) data, uncalibrated Type Ia supernovae (SNe) data from Pantheon+ and Dark Energy Survey (DES) Year 5 (DESY5) samples, and Weak Lensing (WL; DES Year 1) data. The cosmological model consists of six Λ cold dark matter parameters and additionally, the dynamical dark energy parameters (w0, wa), the sum of neutrino masses (∑mν), the effective number of non-photon radiation species (Neff), the scaling of the lensing amplitude (Alens), and the running of the scalar spectral index (αs). Our major findings are the following: (i) With CMB+BAO+DESY5+WL, we obtain the first 2σ+ detection of a non-zero ∑mν=0.19−0.18+0.15 eV (95%). Replacing DESY5 with Pantheon+ still yields a ∼1.9σ detection. (ii) The cosmological constant lies at the edge of the 95% contour with CMB+BAO+Pantheon+ but is excluded at 2σ+ with DESY5, leaving evidence for dynamical dark energy data-set dependent and inconclusive. (iii) With CMB+BAO+SNe+WL, Alens = 1 is excluded at >2σ, while it remains consistent with unity without WL data—suggesting that the existence of lensing anomaly with Planck PR4 likelihoods may depend on non-CMB data sets. (iv) The Hubble tension persists at 3.6σ–4.2σ with CMB+BAO+SNe; WL data have minimal impact.

The distribution of the dark matter (DM) in DM-admixed neutron stars (DANSs) is supposed to result in either a dense dark core or an extended dark halo, subject to the DM fraction of the DANS (f χ ) and the DM properties, such as the mass (m χ ) and the strength of the self-interaction (y). In this paper, we perform an in-depth analysis of the formation criterion for dark cores/dark halos, and point out that the relative distribution of these two components is essentially determined by the ratio of the central enthalpy of the DM component to that of the baryonic matter component inside the DANSs. For the critical case where the radii of the DM and the baryonic matter are the same, we further derive an analytical formula to describe the dependence of fχcrit on m χ and y for a given DANS mass. The relative distribution of the two components in DANSs can lead to different observational effects. We here focus on the modification of the pulsar pulse profile, due to the extra light-bending effect in the case of a dark halo existence, and conduct the first investigation into the dark halo effects on the pulse profile. We find that the peak flux deviation is strongly dependent on the ratio of the halo mass to the radius of the DM component. Last, we perform Bayesian parameter estimation on the DM particle properties, based on the recent X-ray observations of PSR J0030+0451 and PSR J0740+6620 by the Neutron Star Interior Composition Explorer.

The Dark Energy Spectroscopic Instrument (DESI) collaboration recently released the first-year data of baryon acoustic oscillations (BAOs). Based on the five different tracers, the cosmological constraint shows a hint of deviation from the standard ΛCDM model. In this Letter, we combine the DESI BAOs with other cosmic probes to constrain the evolution of the Hubble constant as a function of redshift in the flat ΛCDM model. The nonparametric method is used to estimate the value of the Hubble constant at different redshift bins. The correlations among different bins are removed by diagonalizing the covariance matrix. The joint data sample demonstrates a decreasing trend of the Hubble constant with a significance of 6.4σ, which can naturally resolve the Hubble tension. To avoid statistical effects caused by the binning methods, we tested three other different binning methods and also found a decreasing trend. It may be due to dynamical dark energy or modified gravity.