We give an overview of the old and new topic, “charge symmetry”, a basic concept in nuclear physics. Old data implied that this symmetry might be broken largely for Λ hypernuclei. The ...state-of-the-art experimental techniques we developed, the decay π spectroscopy of electro-produced hypernuclei and the γ-ray spectroscopy of hypernuclei with a Ge detector array, have established the existence of a large charge symmetry breaking in 4ΛH and 4ΛHe hypernuclei.
X-ray spectroscopy of hadronic atoms is a powerful method to study strong interaction between hadrons and nuclei. At J-PARC, we have conducted two experiments, J-PARC E07 and E03, for hadronic atoms ...with a doubly strange hyperon, Ξ
−
, aiming at the world-first detection of their X-rays. The first measurement is performed as a byproduct of J-PARC E07 experiment with the hybrid emulsion technique. The second one, J-PARC E03, is a dedicated experiment for detection of Ξ
−
Fe atom X rays. The preliminary results and the present status of E07 and E03 are shown in this article. Future prospects of Ξ
−
-atomic X-ray spectroscopy are also discussed. A new measurement has been proposed for detecting Ξ
−
C atom X rays, where a novel Ξ
−
tracking method will be applied to realize an improved signal to noise ratio.
To understand the mechanism of the charge symmetry breaking between
4
Λ
H and
4
Λ
He, we plan to measure the gamma-transition energy of
4
Λ
H (1
+
→ 0
+
) with a Ge detector array. For identification ...of the hypernucleus, we will perform triple coincidence with the reaction,
γ
-ray, and weak decay for the first time. We measure the pion from weak decay with a range counter. This method will enable
γ
-ray spectroscopy of various hyperfragments which cannot be directly produced by (
K
−
,
π
−
) or (
π
+
,
K
+
) reactions.
The J-PARC Hadron Experimental Facility was constructed with an aim to explore the origin and evolution of matter in the universe through experiments with intense particle beams. In the past decade, ...many results from particle and nuclear physics experiments have been obtained at the present facility. To expand the physics programs to as yet unexplored regions, the extension project of the Hadron Experimental Facility has been extensively discussed. This contribution presents the physics of the extension of the Hadron Experimental Facility to resolve issues related to strangeness nuclear physics, hadron physics, and flavor physics.
Photoproduction of the neutral kaon on the deuteron has been investigated at the Research Center for Electron Photon Science, Tohoku University. We constructed the Neutral Kaon Spectrometer-2 for the ...detection of charged particles from the decay of the neutral kaon and the hyperon. We obtained a momentum distribution of
K
0
with the inclusive measurement. It was consistent with the previous measurement. The total cross section of
γ + d
→
K
0
+ Λ +
p
was estimated from the measured integral cross section of
γ + d
→ Λ +
X
. The total cross section with respect to the photon energy was compared with the theoretical calculations. It favored the Saclay-Lyon A model calculation with the ratio of the neutral to charged coupling constants of the axial-vector meson,
K
1
, as ~ −1.5. The energy dependence and the magnitude of the total cross section were similar to the total cross section of
γ + p → K
+
Λ.
Beam and SKS spectrometers at the K1.8 beam line Takahashi, Toshiyuki; Adachi, Satoshi; Agnello, Michelangelo ...
Progress of theoretical and experimental physics,
01/2012, Volume:
2012, Issue:
1
Journal Article
We performed a novel Σ
+
p
scattering experiment at the J-PARC Hadron Experimental Facility. Approximately 2400 Σ
+
p
scattering events were identified by a kinematical consistency check for the ...recoil proton. The differential cross sections of the Σ
+
p
elastic scattering were derived with better precision than in previous experiments. By exploiting high-quality differential cross section data and the simple representation of Σ
+
p
interaction in the SU(3) flavor symmetry, we performed a phase-shift analysis on hyperon-nucleon scattering data for the first time. The absolute value of the phase shift of the
3
S
1
channel, where a large repulsive force was predicted due to the Pauli exclusive effect between quarks, was evaluated. These results indicate that the interaction of the
3
S
1
channel in the Σ
+
p
channel is moderately repulsive, as the Nijmegen extended-soft-core models predicted.
We performed a novel Σ+p scattering experiment at the J-PARC Hadron Experimental Facility. Approximately 2400 Σ+p scattering events were identified by a kinematical consistency check for the recoil ...proton. The differential cross sections of the Σ+p elastic scattering were derived with better precision than in previous experiments. By exploiting high-quality differential cross section data and the simple representation of Σ+p interaction in the SU(3) flavor symmetry, we performed a phase-shift analysis on hyperon-nucleon scattering data for the first time. The absolute value of the phase shift of the 3S1 channel, where a large repulsive force was predicted due to the Pauli exclusive effect between quarks, was evaluated. These results indicate that the interaction of the 3S1 channel in the Σ+p channel is moderately repulsive, as the Nijmegen extended-soft-core models predicted.
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