ALPHA CLUSTERING AND CONDENSATION IN 16O

2010 ◽  
Vol 25 (21n23) ◽  
pp. 1939-1942
Author(s):  
Y. FUNAKI ◽  
T. YAMADA ◽  
H. HORIUCHI ◽  
G. RÖPKE ◽  
P. SCHUCK ◽  
...  

The α-particle condensed state in 16 O is investigated by the use of 4α OCM (Orthogonality Condition Model). Low-lying spectrum in experiment is well reproduced up to around the 4α break-up threshold. The excited state obtained around the 4α threshold as the [Formula: see text] state is shown to have a dilute density structure and give strong enhancement of the occupation of the S-state c.o.m. orbital of the α-particles. This is strong evidence that the state is regarded as the 4α condensed state.

2009 ◽  
Vol 18 (10) ◽  
pp. 2083-2087
Author(s):  
Y. FUNAKI ◽  
T. YAMADA ◽  
H. HORIUCHI ◽  
G. RÖPKE ◽  
P. SCHUCK ◽  
...  

The α-particle condensed state in 16 O is investigated by the use of 4α OCM (Orthogonality Condition Model). Low-lying spectrum in experiment is well reproduced up to around the 4α threshold. Furthermore, the excited state obtained around the 4α threshold as the [Formula: see text] state is shown to have a dilute density structure and give strong enhancement of the occupation of the S-state c.o.m. orbital of the α-particles. This is strong evidence that the state is regarded as the 4α condensed state. It also has a large component of [Formula: see text] configuration, which is another reliable evidence of the state to be of 4α condensate nature.


2011 ◽  
Vol 20 (04) ◽  
pp. 874-879 ◽  
Author(s):  
Y. FUNAKI ◽  
T. YAMADA ◽  
H. HORIUCHI ◽  
G. RÖPKE ◽  
P. SCHUCK ◽  
...  

Low density states near the 3α and 4α breakup threshold in 12 C and 16 O , respectively, are discussed in terms of the α-particle condensation. Calculations are performed in OCM (Orthogonality Condition Model) and THSR (Tohsaki-Horiuchi-Schuck-Röpke) approaches. The [Formula: see text] state in 12 C and the [Formula: see text] state in 16 O are shown to have dilute density structures and give strong enhancement of the occupation of the S-state c.o.m. orbital of the α-particles. The possibility of the existence of α-particle condensed states in heavier nα nuclei is also discussed.


2008 ◽  
Vol 17 (10) ◽  
pp. 2087-2095 ◽  
Author(s):  
Y. FUNAKI ◽  
T. YAMADA ◽  
H. HORIUCHI ◽  
G. RÖPKE ◽  
P. SCHUCK ◽  
...  

Low density states near the 3α and 4α breakup threshold in 12 C and 16 O , respectively, are discussed in terms of the α-particle condensation. Calculations are performed in OCM (Orthogonality Condition Model) and THSR (Tohsaki-Horiuchi-Schuck-Röpke) approaches. The [Formula: see text] state in 12 C and the [Formula: see text] state in 16 C are shown to have dilute density structures and give strong enhancement of the occupation of the S-state c.o.m. orbital of the α-particles. The [Formula: see text] state in 16 C has a large component of [Formula: see text] configuration, which is another reliable evidence of the state to be of 4α condensate nature. The possibility of the existence of α-particle condensed states in heavier nα nuclei is also discussed.


2008 ◽  
Vol 17 (10) ◽  
pp. 2101-2105 ◽  
Author(s):  
TAIICHI YAMADA ◽  
YASURO FUNAKI

The structure of 13 C is studied with the semi-microscopic cluster model, 3α+n orthogonality condition model (OCM). The energy spectra of four 1/2- states and three 1/2+ states up to Ex ~ 13 MeV are successfully reproduced, in particular, three monopole transition strengths are in fair agreement with the observed ones. We discuss the cluster states and alpha particle condensation in the 1/2± states appearing around the 12 C +n, 9 Be +α and 3α+n thresholds.


1987 ◽  
Vol 98 (5) ◽  
pp. 529-537 ◽  
Author(s):  
S. M. Saad ◽  
V. B. Subbotin ◽  
K. A. Gridnev ◽  
E. F. Hefter ◽  
V. M. Semjonov

1950 ◽  
Vol 28a (6) ◽  
pp. 616-627 ◽  
Author(s):  
E. Pickup ◽  
L. Voyvodic

One of the more interesting features of cosmic ray stars is that [Formula: see text] nuclei are ejected occasionally in the nuclear disintegrations. Such nuclei are characterized by the fact that, at the end of their range, they suffer radioactive decay (τ = 0.9 sec.) into [Formula: see text], which immediately splits up into two oppositely directed α-particles, giving what is usually referred to as a hammer track. In this investigation numerous examples have been observed of the emission of such nuclei in stars in photographic emulsions, the stars having from 2 to 60 prongs. In particular, it has been shown that the energy spectrum of the α-particles forming the hammer tracks is in good agreement with that observed by other workers, and also with experiments made, using the cloud chamber technique, indicating that the [Formula: see text] in this disintegration is formed in the excited state. When an electron sensitive emulsion is used it is shown that the hammer track is accompanied by the [Formula: see text] disintegration electron. The energy spectrum of the [Formula: see text] nuclei is plotted, and the mechanism of the formation is discussed for both large and small stars.


2008 ◽  
Vol 101 (8) ◽  
Author(s):  
Y. Funaki ◽  
T. Yamada ◽  
H. Horiuchi ◽  
G. Röpke ◽  
P. Schuck ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document