We investigate Λ production in the ( <math altimg='si146.svg'><msup><mrow><mi>&#960;</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>, <math altimg='si3.svg'><msup><mrow><mi>K</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>) reaction on a 6Li target at <math altimg='si4.svg'><msub><mrow><mi>p</mi></mrow><mrow><msup><mrow><mi>&#960;</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></mrow></msub><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><mn>1.05</mn></math> GeV/ <italic>c</italic>, using the distorted-wave impulse approximation (DWIA) with the Fermi-averaged <math altimg='si5.svg'><msup><mrow><mi>&#960;</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup><mi>n</mi><mo stretchy='false'>&#8594;</mo><msup><mrow><mi>K</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup><mi mathvariant='normal'>&#923;</mi></math> amplitudes. The calculated spectrum is in good agreement with the experimental data, suggesting that <math altimg='si1.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts></math>- <italic>d</italic> configurations play a key role in describing the &#923; continuum states of <math altimg='si23.svg'><msubsup><mrow /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>6</mn></mrow></msubsup></math>Li near and above the <math altimg='si8.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><none /><mrow><mn>3</mn></mrow></mmultiscripts><mo linebreak='goodbreak' linebreakstyle='after'>+</mo><mi>d</mi><mo linebreak='goodbreak' linebreakstyle='after'>+</mo><mi mathvariant='normal'>&#923;</mi></math> threshold. Our analysis shows that the <math altimg='si1.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts></math> hypernucleus as a hyperfragment is prominently produced through <italic>D</italic>-wave resonances with <math altimg='si9.svg'><msup><mrow><mi>J</mi></mrow><mrow><mi>P</mi></mrow></msup><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><msup><mrow><mn>3</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>, <math altimg='si10.svg'><msup><mrow><mn>2</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>, and <math altimg='si11.svg'><msup><mrow><mn>1</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math> in the <math altimg='si108.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts><mo linebreak='goodbreak' linebreakstyle='after'>+</mo><mi>d</mi></math> channel at a large momentum transfer <math altimg='si13.svg'><mi>q</mi><mo>&#8771;</mo><mn>360</mn></math>&#8211;400 MeV/ <italic>c</italic>. These findings provide theoretical evidence for the production of a <math altimg='si1.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts></math> hyperfragment via a cluster-like mechanism in the 6Li( <math altimg='si146.svg'><msup><mrow><mi>&#960;</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>, <math altimg='si3.svg'><msup><mrow><mi>K</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>) reaction.

Japan

Toru Harada

Yoshiharu Hirabayashi

Evidence for <math altimg='si1.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts></math> hyperfragment production in the 6Li( <italic>&#960;</italic> +, <italic>K</italic> +) reaction

The ultralight dark photon is an intriguing dark matter candidate. The interaction between visible and dark photons is introduced by the gauge kinetic mixing between the field strength tensors of the Abelian gauge groups in the Standard Model and dark sector. Relativistic electrodynamics was generalized to quantum electromagnetodynamics (QEMD) in the presence of both electric and magnetic charges. The photon is described by two four-potentials corresponding to two $ U(1) $ gauge groups and satisfying non-trivial commutation relations. In this work, we construct low-energy dark photon-photon interactions in the QEMD framework and obtain new dark photon-photon kinetic mixings. Then, we derive the consequent field and Maxwell's equations. We also investigate the detection strategies of dark photons as light dark matter and generic kinetic mixings at haloscope experiments.

China

Chang-Jie Dai

Tong Li

Rui-Jia Zhang

Dark photon dark matter in quantum electromagnetodynamics and detection at haloscope experiments * Li Tong is supported by the National Natural Science Foundation of China (12375096, 12035008, 11975129)

In-medium Λ <italic>N</italic> interactions are crucial in hypernuclei and neutron star physics. In this work, we study the in-medium &#923; <italic>N</italic> interaction within the relativistic Brueckner-Hartree-Fock (RBHF) framework, employing the leading-order covariant chiral hyperon/nucleon-nucleon forces for the first time. We demonstrate that a consistent description of both the experimental cross-section data and the &#8216;empirical value&#8217; of the &#923; single-particle potential can be achieved. This contrasts with the majority of studies in the non-relativistic framework, where higher-order two-body chiral forces are typically required. This study offers a new perspective on the in-medium &#923; <italic>N</italic> interactions, urgently needed in relativistic <italic>ab initio</italic> hypernuclear physics studies.

Ru-You Zheng

Zhi-Wei Liu

Li-Sheng Geng

Jin-Niu Hu

Sibo Wang

In-medium Λ <italic>N</italic> interactions with leading order covariant chiral hyperon/nucleon-nucleon forces

The Weinberg compositeness criterion dictates that a pure shallow bound state is characterized by a large scattering length <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>a</mi><mn>0</mn></msub><mo>≫</mo><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mn>1</mn><mo>/</mo><mi>β</mi><mo stretchy="false">)</mo></math> and a positive effective range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>r</mi><mn>0</mn></msub></math> that naturally scales to the size of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mn>1</mn><mo>/</mo><mi>β</mi><mo stretchy="false">)</mo></math>, where <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mo>/</mo><mi>β</mi></math> signifies the interaction range. In constructing the contact-range effective field theory (EFT) up to the next-to-leading order to describe the pentaquarks <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4312</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4440</mn><mo stretchy="false">)</mo></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4457</mn><mo stretchy="false">)</mo></math> observed by the LHCb collaboration in 2019, we match the effective range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>r</mi><mn>0</mn></msub></math> at single-channel situation for these pentaquarks with the low-energy couplings within the EFT framework. Three different schemes are used to connect the couplings with the effective range. We find positive effective ranges <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>r</mi><mn>0</mn></msub></math> of the natural size of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mn>1</mn><mo>/</mo><mi>β</mi><mo stretchy="false">)</mo></math> for the spin configurations <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>J</mi><mi>P</mi></msup><mo>=</mo><msup><mfrac><mn>3</mn><mn>2</mn></mfrac><mo>−</mo></msup></math> for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4440</mn><mo stretchy="false">)</mo></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>J</mi><mi>P</mi></msup><mo>=</mo><msup><mfrac><mn>1</mn><mn>2</mn></mfrac><mo>−</mo></msup></math> for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4457</mn><mo stretchy="false">)</mo></math> within the molecular <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mo>*</mo></msup><msub><mi mathvariant="normal">Σ</mi><mi>c</mi></msub></math> description. Additionally, predictions from the power counting for low-energy couplings or Wilsonian coefficients suggest that, under heavy quark spin symmetry, the broad <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4380</mn><mo stretchy="false">)</mo></math> resonance, discovered by the LHCb collaboration in 2015, when considered as part of the single-channel <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mrow><mo stretchy="false">(</mo><mo>*</mo><mo stretchy="false">)</mo></mrow></msup><msubsup><mi mathvariant="normal">Σ</mi><mi>c</mi><mrow><mo stretchy="false">(</mo><mo>*</mo><mo stretchy="false">)</mo></mrow></msubsup></math> molecular system alongside <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4312</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4440</mn><mo stretchy="false">)</mo></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4457</mn><mo stretchy="false">)</mo></math>, has a mass of approximately <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>4376</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></mrow></math>.

Fang-Zheng Peng

Ju-Jun Xie

Constraining the hidden-charm pentaquark predictions and discriminating the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>P</mi></mrow><mrow><mi>c</mi></mrow></msub><mo stretchy="false">(</mo><mn>4440</mn><mo stretchy="false">)</mo></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>P</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>4457</mn><mo stretchy="false">)</mo></math> spins through the effective range expansion

We have studied the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>N</mi><msup><mrow><mi>D</mi></mrow><mrow><mo>*</mo></mrow></msup><msup><mrow><mover accent="true"><mrow><mi>K</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mo>*</mo></mrow></msup></mrow></math> system in the framework of the fixed center approximation to the Faddeev equations, taking the exotic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>*</mo></msup><msup><mover accent="true"><mi>K</mi><mo stretchy="false">¯</mo></mover><mo>*</mo></msup></math> system as the cluster and allowing the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>N</mi></math> to interact with the components of the cluster. Previous studies have determined the existence of three states of spin 0, 1, 2 for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mo>*</mo></msup><msup><mover accent="true"><mi>K</mi><mo stretchy="false">¯</mo></mover><mo>*</mo></msup></math> system, the one of spin 0 associated to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>X</mi><mn>0</mn></msub><mo stretchy="false">(</mo><mn>2900</mn><mo stretchy="false">)</mo></math> state observed by the LHCb Collaboration. From this perspective, we find five states with total spin <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mo>/</mo><mn>2</mn><mo>,</mo><mn>3</mn><mo>/</mo><mn>2</mn><mo>,</mo><mn>5</mn><mo>/</mo><mn>2</mn></math>, with bindings from 10 to 30 MeV and widths below 60 MeV, which could be well identified. We also discuss the decay channels of these states that should help in future experimental searches for these states.

Qing-Yu Zhai

Spain

Raquel Molina

Eulogio Oset

Study of the exotic three-body <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>N</mi><msup><mrow><mi>D</mi></mrow><mrow><mo>*</mo></mrow></msup><msup><mrow><mover accent="true"><mrow><mi>K</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mo>*</mo></mrow></msup></mrow></math> system

A recent analysis of the LHCb data [Esposito et al., <a href="http://dx.doi.org/10.1103/PhysRevD.105.L031503">Phys. Rev. D 105 L031503 (2022)</a>] obtained a sizable negative effective range for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3872</mn><mo stretchy="false">)</mo></math>. This has attracted intensive discussions on whether <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3872</mn><mo stretchy="false">)</mo></math> can be deemed as a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><msup><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mo>*</mo></msup></math> molecular state. This work explicitly demonstrates that the negative effective range of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3872</mn><mo stretchy="false">)</mo></math> does not contradict the molecular picture, adopting an effective field theory formulation of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><msup><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mo>*</mo></msup></math> interaction that can simultaneously reproduce the binding energy and effective range of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3872</mn><mo stretchy="false">)</mo></math>. We elaborate on the implications of the large negative effective range of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3872</mn><mo stretchy="false">)</mo></math> and the small binding energy on the underlying <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><msup><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mo>*</mo></msup></math> interaction. Such results are relevant for a better understanding of hadronic molecules and their binding mechanism.

Yi-Bo Shen

Ming-Zhu Liu

Implication of a negative effective range on the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><msup><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mo>*</mo></msup></math> interaction and the nature of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3872</mn><mo stretchy="false">)</mo></math>

Cryogenic calorimetric experiments to search for neutrinoless double-beta decay ( $$0\nu \beta \beta $$ ) are highly competitive, scalable and versatile in isotope. The largest planned detector array, CUPID, is comprised of about 1500 individual Li $$_{2}$$ $$^{100}$$ MoO $$_4$$ detector modules with a further scale up envisioned for a follow up experiment (CUPID-1T). In this article, we present a novel detector concept targeting this second stage with a low impedance TES based readout for the Li $$_2$$ MoO $$_4$$ absorber that is easily mass-produced and lends itself to a multiplexed readout. We present the detector design and results from a first prototype detector operated at the NEXUS shallow underground facility at Fermilab. The detector is a 2-cm-side cube with 21 g mass that is strongly thermally coupled to its readout chip to allow rise-times of $$\sim $$ 0.5 ms. This design is more than one order of magnitude faster than present NTD based detectors and is hence expected to effectively mitigate backgrounds generated through the pile-up of two independent two neutrino decay events coinciding close in time. Together with a baseline resolution of 1.95 keV (FWHM) these performance parameters extrapolate to a background index from pile-up as low as $$5\cdot 10^{-6}$$ counts/keV/kg/yr in CUPID size crystals. The detector was calibrated up to the MeV region showing sufficient dynamic range for $$0\nu \beta \beta $$ searches. In combination with a SuperCDMS HVeV detector this setup also allowed us to perform a precision measurement of the scintillation time constants of Li $$_2$$ MoO $$_4$$ , which showed a primary component with a fast O(20 $$\upmu $$ s) time scale.

United States

G. Bratrud

C. Chang

R. Chen

Canada

E. Cudmore

E. Figueroa-Feliciano

Z. Hong

K. Kennard

S. Lewis

M. Lisovenko

L. Mateo

V. Novati

V. Novosad

France

E. Oliveri

R. Ren

J. Scarpaci

B. Schmidt

G. Wang

L. Winslow

V. Yefremenko

J. Zhang

D. Baxter

M. Hollister

C. James

P. Lukens

D. Temples

First demonstration of a TES based cryogenic Li $$_2$$ MoO $$_4$$ detector for neutrinoless double beta decay search

The decay behavior of an exotic state can be used to probe its internal structure. We note that the hidden-charm pentaquark states, <math><mrow><msubsup><mrow><mi>P</mi></mrow><mrow><mi>ψ</mi></mrow><mrow><mi>N</mi></mrow></msubsup><mo>(</mo><mn>4312</mn><mo>)</mo></mrow></math>, <math><msubsup><mi>P</mi><mi>ψ</mi><mi>N</mi></msubsup><mo>(</mo><mn>4440</mn><mo>)</mo></math>, and <math><msubsup><mi>P</mi><mi>ψ</mi><mi>N</mi></msubsup><mo>(</mo><mn>4457</mn><mo>)</mo></math>, have only been observed in the <math><mi>J</mi><mo>/</mo><mi>ψ</mi><mi>p</mi></math> channel. In this work, we employ the effective Lagrangian approach to systematically investigate the two-body and three-body decays of the heavy quark spin symmetry multiplet of hadronic molecules <math><msup><mover><mi>D</mi><mo>¯</mo></mover><mrow><mo>(</mo><mo>*</mo><mo>)</mo></mrow></msup><msubsup><mi>Σ</mi><mi>c</mi><mrow><mo>(</mo><mo>*</mo><mo>)</mo></mrow></msubsup></math>. Our results show that the partial decay widths of the hidden-charm pentaquark molecules into <math><msup><mover><mi>D</mi><mo>¯</mo></mover><mrow><mo>(</mo><mo>*</mo><mo>)</mo></mrow></msup><msub><mi>Λ</mi><mi>c</mi></msub><mi>π</mi></math> are sizable so that <math><msup><mover><mi>D</mi><mo>¯</mo></mover><mrow><mo>(</mo><mo>*</mo><mo>)</mo></mrow></msup><msub><mi>Λ</mi><mi>c</mi></msub><mi>π</mi></math> are promising channels to search for them, which can help clarify their molecular nature.

Ya-Wen Pan

Studying the heavy quark spin symmetry multiplet of hadronic molecules <math><mrow><msup><mrow><mover><mrow><mi>D</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow><mrow><mo>(</mo><mo>*</mo><mo>)</mo></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>(</mo><mo>*</mo><mo>)</mo></mrow></msubsup></mrow></math> in the three-body decays of <math><mrow><msup><mrow><mover><mrow><mi>D</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow><mrow><mo>(</mo><mo>*</mo><mo>)</mo></mrow></msup><msub><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow></msub><mi>π</mi></mrow></math>

The ground-breaking discovery of the first fully charmed tetraquark state <math><mi>X</mi><mo>(</mo><mn>6900</mn><mo>)</mo></math> in the <math><mi>J</mi><mo>/</mo><mi>ψ</mi><mi>J</mi><mo>/</mo><mi>ψ</mi></math> invariant mass distribution by the LHCb collaboration has inspired intensive theoretical studies. Various interpretations, such as molecular states, compact tetraquark states, and coupled-channel effects, have been proposed for these states. Of particular interest is the ongoing search for the triple-<math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> state–a fully-charmed hexaquark state. To deepen our understanding of the triple-<math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> state and to guide future experimental searches, we study the triple-<math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> system in this work employing the Gaussian expansion method and the <math><mi>J</mi><mo>/</mo><mi>ψ</mi><mi>J</mi><mo>/</mo><mi>ψ</mi></math> potential parametrized to yield a shallow bound state, as suggested in several theoretical works. Our results support a triple-<math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> bound state, even in cases where the attractive interaction between the two <math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> mesons is very weak. Moreover, our analysis implies the Efimov effect in the triple-<math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> system. In addition, we extend our investigation to the triple-<math><mrow><mi>ϒ</mi><mo>(</mo><mn>1</mn><mi>S</mi><mo>)</mo></mrow></math> system and obtain results similar to those for the triple-<math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> system.

Atsushi Hosaka

Xiang Liu

Likely existence of bound states and the Efimov effect in the triple-<math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> system

Motivated by the recent experimental measurements, we have investigated the Cabibbo-favored process <math><msubsup><mi>Λ</mi><mi>c</mi><mo>+</mo></msubsup><mo>→</mo><mi>p</mi><msup><mover><mi>K</mi><mo>¯</mo></mover><mn>0</mn></msup><mi>η</mi></math>, where the <math><mi>N</mi><mo>(</mo><mn>1535</mn><mo>)</mo></math> resonance is dynamically generated from the <math><mi>S</mi></math>-wave pseudoscalar meson-octet baryon interactions within the chiral unitary approach. The contributions from the intermediate <math><mi>N</mi><mo>(</mo><mn>1650</mn><mo>)</mo></math> and the predicted low-lying baryon <math><msup><mi>Σ</mi><mo>*</mo></msup><mo>(</mo><mn>1</mn><mo>/</mo><msup><mn>2</mn><mo>−</mo></msup><mo>)</mo></math> are also considered. In addition, a Breit-Wigner amplitude for the <math><mi>N</mi><mo>(</mo><mn>1535</mn><mo>)</mo></math> resonance is checked. By comparing with the measured <math><mi>η</mi><mi>p</mi></math>, <math><msup><mover><mi>K</mi><mo>¯</mo></mover><mn>0</mn></msup><mi>η</mi></math>, and <math><mi>p</mi><msup><mover><mi>K</mi><mo>¯</mo></mover><mn>0</mn></msup></math> invariant mass squared distributions, our results support the interpretation of <math><mi>N</mi><mo>(</mo><mn>1535</mn><mo>)</mo></math> as a dynamically generated state. Furthermore, we demonstrate that, with the contribution from <math><msup><mi>Σ</mi><mo>*</mo></msup><mo>(</mo><mn>1</mn><mo>/</mo><msup><mn>2</mn><mo>−</mo></msup><mo>)</mo></math> taken into account, the calculated invariant mass distributions agree with the Belle measurements. Future precise measurements of the <math><msubsup><mi>Λ</mi><mi>c</mi><mo>+</mo></msubsup><mo>→</mo><mi>p</mi><msup><mover><mi>K</mi><mo>¯</mo></mover><mn>0</mn></msup><mi>η</mi></math> process can further elucidate the existence of the low-lying baryon <math><msup><mi>Σ</mi><mo>*</mo></msup><mo>(</mo><mn>1</mn><mo>/</mo><msup><mn>2</mn><mo>−</mo></msup><mo>)</mo></math>.

Ying Li

Si-Wei Liu

En Wang

De-Min Li

Theoretical study of <math><mi>N</mi><mo>(</mo><mn>1535</mn><mo>)</mo></math> and <math><msup><mi>Σ</mi><mo>*</mo></msup><mo>(</mo><mn>1</mn><mo>/</mo><msup><mn>2</mn><mo>−</mo></msup><mo>)</mo></math> in the Cabibbo-favored process <math><msubsup><mi>Λ</mi><mi>c</mi><mo>+</mo></msubsup><mo>→</mo><mi>p</mi><msup><mover><mi>K</mi><mo>¯</mo></mover><mn>0</mn></msup><mi>η</mi></math>