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Kunihiko Terasaki

Publications and source records attributed to Kunihiko Terasaki.

At least 19 recordsLinked to original sources
arXiv2018

Open- and hidden-charm tetra-quark scalar mesons

Masses of open- and hidden-charm tetra-quark scalar mesons are studied in a new approach. As the result, newly estimated masses of hidden-charm sector are significantly lower than our earier ones by a naive quark counting. In particular, our new result on the non-strange iso-triplet scalar mesons should be compared with the experiment that an indication of tiny eta pi peak around 3.2 GeV has been observed, while no signal in the eta_c pi channel.

hep-ph↗
arXiv2016

Tetra-Quark Interpretation of X(3872) and Z_c(3900) Revisited

In relation to the newly observed bottom-strange X^{+,-}(5568) mesons, we revisit our tetra-quark interpretation of X(3872) and Z_c(3900). It is discussed that our assignment of X^{+,-}(5568) to charged components of iso-triplet bottom partners of D_{s0}^+(2317) is compatible with the revised version of our tetra-quark interpretation of X(3872) and Z_c(3900).

hep-ph↗
arXiv2016

Production of Neutral and Doubly Charged Partners of D_{s0}^+(2317) Revisited

Rates for productions of neutral and doubly charged partners of D_{s0}^+(2317) in B meson decays are studied by using a hard D meson approximation in the infinite momentum frame, and the results are of the same order of magnitude as that of D_{s0}^+(2317). Because the bottom-strange X^{+-}(5568) which can be interpreted as iso-triplet bottom partners of D_{s0}^+(2317) have recently been discovered, observations of neutral and doubly charged partners of D_{s0}^+(2317) are strongly desired.

hep-ph↗
arXiv2014

X(3872) --> J/psi pi pi pi as a Three-Step Decay

Rate for the X(3872) --> J/psi pi pi pi decay is studied by assuming that it proceeds as X(3872) --> J/psi omega --> J/psi pi rho --> J/psi pi pi pi. The result is compared with the X(3872) --> J/psi pi pi decay.

hep-ph↗
arXiv2013

Hidden-Strangeness Partners of X(3872)

Decay properties of hidden-strangeness partners of X(3872) are studied in tetra-quark pictures. As the results, it is seen that their decay properties are strongly model dependent, and therefore, experimental studies of them will select a realistic model.

hep-ph↗
arXiv2013

Decay Property of Axial-Vector Tetra-Quark Mesons

Decay property of hidden-charm tetra-quark mesons is studied. It is seen that estimated width of iso-triplet odd $\mathcal{C}$ partners of X(3872), although still crude, is compatible with the measured ones of Z_c(3900). It is pointed out that confirmation of an eta-pi^0 peak around 3.2 GeV indicated in gamma-gamma collisions gives a clue to select a realistic model of multi-quark mesons.

hep-ph↗
arXiv2012

X(3872) and Its Iso-Triplet Partners

Decays of X(3872) and its partners as hidden-charm axial-vector tetra-quark mesons are studied. As the result, it is seen that the iso-triplet partners of X(3872) can be broad, and therefore, higher statistics would be needed to find them.

hep-ph↗
arXiv2009

omega-rho^0 mixing as a possible origin of the hypothetical isospin non-conservation in the X(3872) --> pi^+ pi^- J/psi decay

The ratio of branching fractions Br(X(3872) --> gamma J/psi)/ Br(X(3872) --> pi^+ pi^- J/psi) is studied by assuming that the X(3872) --> pi^+ pi^- J/psi decay proceeds through the rho^0 meson pole which is caused by the omega-rho^0 mixing. As the result, it is seen that the calculated ratio is compatible with the measured values of the ratio when X(3872) is an axial-vector tetra-quark state, while it would be much larger than the measurements when it is a charmonium. Therefore, the existing data on the ratio seem to favor the tetra-quark interpretation of X(3872) over the charmonium, although a small mixing of the charmonium is not excluded.

hep-ph↗
arXiv2008

Hidden-charm scalar tetra-quark mesons

Decays of hidden-charm scalar tetra-quark mesons as the partners of D_{s0}(2317) which has successfully been assigned to the iso-triplet scalar tetra-quark [c,n][sbar,nbar]_{I=1} meson are studied. Because OZI-rule allowed strong decays are kinematically limited, their radiative decays are expected to be important.

hep-ph↗
arXiv2008

Charmed Scalar Resonances

It is pointed out that assigning D_{s0}^+(2317) to an iso-triplet tetra-quark meson is favored by experiments. It also is discussed why its neutral and doubly charged partners have never been observed in inclusive e^+e^- annihilation. To search for them, hadronic weak decays of B mesons would be better, and their production rates, Br(B_u^+ -> D^-D_{s0}^{++}(2317)) and Br(B_d^0 ->antiD^0D_{s0}^{0}(2317)), would be around 10^{-3}.

hep-ph↗
arXiv2007

A new tetra-quark interpretation of X(3872)

A new tetra-quark interpretation of X(3872) is presented. In this model, X(3872) consists of two degenerate tetra-quark mesons, {[cn](cbar nbar) +- (cn)[cbar nbar]}_{I=0}, and, therefore, it is naturally understood that X(3872) decays into two different eigenstates of G-parity.

hep-ph↗
arXiv2007

D_{s0}^+(2317) as an Iso-triplet Four-quark Meson and Production of Its Neutral and Doubly Charged Partners

By studying the decays D_{s0}^+(2317) --> D_s^+ pi^0 and D_s^{*+} gamma, It is shown that its assignment to the I_3=0 component of iso-triplet scalar four-quark mesons is favored. Productions of its neutral and doubly charged partners are also studied. As the result, it is concluded that they could be observed in B decays. Their iso-singlet partner might have been observed in the radiative channels of B decays by the BELLE Collaboration.

hep-ph↗
arXiv2006

D_{s0}^+(2317) as an iso-triplet four-quark meson

Although assigning D_{s0}^+(2317) to the I_3=0 component of iso-triplet four-quark mesons is favored by experiments, its neutral and doubly charged partners have not yet been observed. It is discussed why they were not observed in inclusive e^+e^- annihilation experiments and that they can be observed in B decays.

hep-ph↗
arXiv2006

Production of neutral and doubly charged partners of D_{s0}^+(2317)

Production of neutral and doubly charged partners, $\hat F_I^0$ and $\hat F_I^{++}$, of $ D_{s0}^+(2317)$ as a charm-strange four-quark meson is studied in relation to observations of $D_{s0}^+(2317)$. It is discussed that observation of $\hat F_I^{++}$ in inclusive $e^+e^-\to c\bar c$ is difficult but it might be observed in $B_u^+\to D_s^+π^+D^-$. Observations of $\hat F_I^0$ and $\hat F_0^+$ might be possible in hadronic B decays.

hep-ph↗