ترغب بنشر مسار تعليمي؟ اضغط هنا

Confirmation of the isomeric state in 26P

185   0   0.0 ( 0 )
 تاريخ النشر 2017
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We report the independent experimental confirmation of an isomeric state in the proton drip-line nucleus $^{26}$P. The ${gamma}$-ray energy and half-life determined are 164.4 $pm$ 0.3 (sys) $pm$ 0.2 (stat) keV and 104 $pm$ 14 ns, respectively, which are in agreement with the previously reported values. These values are used to set a semi-empirical limit on the proton separation energy of $^{26}$P, with the conclusion that it can be bound or unbound.



قيم البحث

اقرأ أيضاً

131 - A. Dijon 2012
We report on the observation of a new isomeric state in $^{68}$Ni. We suggest that the newly observed state at 168(1) keV above the first 2$^+$ state is a $pi(2p-2h)$ 0$^{+}$ state across the major Z=28 shell gap. Comparison with theoretical calculat ions indicates a pure proton intruder configuration and the deduced low-lying structure of this key nucleus suggests a possible shape coexistence scenario involving a highly deformed state.
111 - D. Perez-Loureiro 2016
Background: Measurements of $beta$ decay provide important nuclear structure information that can be used to probe isospin asymmetries and inform nuclear astrophysics studies. Purpose: To measure the $beta$-delayed $gamma$ decay of $^{26}$P and compa re the results with previous experimental results and shell-model calculations. Method: A $^{26}$P fast beam produced using nuclear fragmentation was implanted into a planar germanium detector. Its $beta$-delayed $gamma$-ray emission was measured with an array of 16 high-purity germanium detectors. Positrons emitted in the decay were detected in coincidence to reduce the background. Results: The absolute intensities of $^{26}$P $beta$-delayed $gamma$-rays were determined. A total of six new $beta$-decay branches and 15 new $gamma$-ray lines have been observed for the first time in $^{26}$P $beta$-decay. A complete $beta$-decay scheme was built for the allowed transitions to bound excited states of $^{26}$Si. $ft$ values and Gamow-Teller strengths were also determined for these transitions and compared with shell model calculations and the mirror $beta$-decay of $^{26}$Na, revealing significant mirror asymmetries. Conclusions: A very good agreement with theoretical predictions based on the USDB shell model is observed. The significant mirror asymmetry observed for the transition to the first excited state ($delta=51(10)%$) may be evidence for a proton halo in $^{26}$P.
Mass-separated 187Ta in a high-spin isomeric state has been produced for the first time by multi-nucleon transfer reactions, employing an argon gas stopping cell and laser ionisation. Internal gamma rays revealed a 7.3 s isomer at 1778 keV, which dec ays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer decay reduced E2 hindrance factor of 27 supports the interpretation that axial symmetry is approximately conserved.
The isomeric and {beta} decays of the N = Z +2 nucleus 96Ag were investigated at NSCL. A cascade of {gamma}-ray transitions originating from the de-excitation of a {mu}s isomer was observed for the first time and was found in coincidence with two pre viously-known transitions with energies of 470 and 667 keV. The isomeric half-life was determined as 1.45(7) {mu}s, more precise than previously reported. The existence of a second, longer-lived {mu}s isomer, associated with a 743-keV transition, is also proposed here. Shell model results within the (p_{3/2}p_{1/2}f_{5/2}g_{9/2}) model space, using the jj44b interaction, reproduced level energies and isomeric decay half-lives reasonably well.
Neutron-rich nuclei were populated in a relativistic fission of 238U. Gamma-rays with energies of 135 keV and 184 keV were associated with two isomeric states in 121Pd and 117Ru. Half-lives of 0.63(5) microseconds and 2.0(3) micrisecondss were deduce d and the isomeric states were interpreted in terms of deformed single-particle states.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا