Tue·Jul 16, 2019Tuesday·July 16, 2019

1. 01*

   Competing quasifission and asymmetric fusion-fission in neutron-deficient sub-lead nuclei

   Shilpi Gupta🇮🇳 · K. Mahata🇮🇳 · A. Shrivastava🇮🇳 · K. Ramachandran🇮🇳 · S.K. Pandit🇮🇳 · P.C. Rout🇮🇳 · V.V. Parkar🇮🇳 · R. Tripathi🇮🇳 · A. Kumar🇮🇳 · B.K. Nayak🇮🇳 · E.T. Mirgule🇮🇳 · A. Saxena🇮🇳 and 6 other authors

   To disentangle the role of shell effects and dynamics, fission fragment mass distributions of ${}^{191}$Au, a nucleus in the newly identified island of mass asymmetric fission in the sub-lead region, have been measured down to excitation energy of $\approx$20 MeV above the fission barrier via two different entrance channels, viz. ${}^{16}$O+${}^{175}$Lu and ${}^{37}$Cl+${}^{154}$Sm reactions. Apart from having signature of the shell effects in both the cases, clear experimental evidence of quasifission has been observed in the mass distributions of the Cl induced reaction, that has also been substantiated by the theoretical calculations. This crucial evidence along with a systematic analysis of available experimental data has revealed that the dynamics in the entrance channel has significant influence on most of the reactions used earlier to explore the persistence of recently discovered mass asymmetry in $\beta$-delayed fission at low energy in this mass region, ignoring which might lead to ambiguity in interpreting the heavy-ion data.

   nucl-exnucl-thPLB(2020)·31 citations
2. 02*

   Power corrections in semi-inclusive deep inelastic scatterings at fixed target energies

   Tianbo Liu🇺🇸 · Jian-Wei Qiu🇺🇸

   The COMPASS collaboration published precise data on production cross section of charged hadrons in lepton-hadron semi-inclusive deep inelastic scattering, showing almost an order of magnitude larger than next-to-leading order QCD calculations when $P_{h_T}$ and $z_h$ are sufficiently large. We explore the role of power corrections to the theoretical calculations, and quantitatively demonstrate that the power corrections are extremely important for these data when the final-state multiplicity is low and the production kinematics is near the edge of phase space. Our finding motivates more detailed studies on power corrections for upcoming experiments at Jefferson Lab, as well as the future Electron-Ion Collider.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2020)·13 citations
3. 03*

   Study of radioactivity built-up and decay with singles time-stamped data

   Sangeeta Das · Arkajyoti De🇮🇳 · Balaram Dey🇮🇳 · Sathi Sharma · Anik Adhikari · S. S. Alam🇮🇳 · Arkabrata Gupta🇮🇳 · Y. Sapkota · Ananya Das · A. Saha🇺🇸 · Dibyadyuti Pramanik · T. Bhattacharjee🇮🇳 and 3 other authors

   Time-stamped data have been used to estimate the decay half-lives of radioactive 118mSb and 64,66,68Ga nuclei. These nuclei are populated through the reaction 4He (Elab = 32 MeV) + nat In and p (Elab = 10 MeV) + natZn, respectively. The g -rays emitted by the excited daughter nuclei are detected by a single high purity germanium (HPGe) detector and the data are acquired using a CAEN 5780M desktop digitizer. Half-lives of different orders of magnitudes for the above mentioned nuclei are obtained from both the decay of parent and the growth of daughter nuclei. It is observed that the half-lives obtained from both these techniques match fairly well and also are consistent with the reported values. It is demonstrated that the time-stamped data can be useful while studying certain half-lives which are too long for measurement using in-beam electronic technique and too short for decay studies in off-beam methods. The data also have a special relevance for constant monitoring of beam current and beam-tuning.

   ↳ physics.ins-detnucl-exnucl-thJINST(2019)·2 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.