Wed·Sep 20, 2017Wednesday·September 20, 2017

1. 01*

   Disentangling the role of vibration, rotation, and neutron transfer in the fusion of neutron-rich mid-mass nuclei

   J. Vadas🇺🇸 · Varinderjit Singh🇺🇸 · B.B. Wiggins🇺🇸 · J. Huston🇺🇸 · S. Hudan🇺🇸 · R.T. deSouza🇺🇸 · Z. Lin🇺🇸 · C.J. Horowitz🇺🇸 · A. Chbihi🇫🇷 · D. Ackermann🇫🇷 · M. Famiano🇺🇸 · K.W. Brown🇺🇸

   We report the first measurement of the fusion excitation functions for ${}^{39,47}$K + ${}^{28}$Si at near-barrier energies. Evaporation residues resulting from the fusion process were identified by direct measurement of their energy and time-of-flight with high geometric efficiency. At the lowest incident energy, the cross-section measured for the neutron-rich ${}^{47}$K induced reaction is ~6 times larger than that of the $\beta$-stable system. The experimental data are compared with both a dynamical deformation model and coupled channels calculations (CCFULL).

   nucl-exPRC(2018)·11 citations
2. 02*

   First direct mass measurements of nuclides around $Z=100$ with a Multireflection Time-of-Flight Mass Spectrograph

   Y. Ito🇯🇵 · P. Schury🇯🇵 · M. Wada🇯🇵 · F. Arai🇯🇵 · H. Haba🇯🇵 · Y. Hirayama🇯🇵 · S. Ishizawa🇯🇵 · D. Kaji🇯🇵 · S. Kimura🇯🇵 · H. Koura🇯🇵 · M. MacCormick🇫🇷 · H. Miyatake🇯🇵 and 14 other authors

   The masses of ${}^{246}$Es, ${}^{251}$Fm and the transfermium nuclei ${}^{249-252}$Md, and ${}^{254}$No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed $N=152$ neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. The masses of ${}^{246}$Es and ${}^{249,250,252}$Md were measured for the first time. Using the masses of ${}^{249,250}$Md as anchor points for $\alpha$ decay chains, the masses of heavier nuclei, up to ${}^{261}$Bh and ${}^{266}$Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter ${\delta }_{2n}$ derived from three isotopic masses was updated with the new masses and corroborate the existence of the deformed $N=152$ neutron shell closure for Md and Lr.

   nucl-exPRL(2018)·53 citations
3. 03*

   Double Beta Decay to the Excited States: Review

   A.S. Barabash🇷🇺

   A brief review of double beta decay to the excited states of daughter nuclei is given. Results of the most sensitive experiments are presented.

   nucl-exAIP Conf.Proc.(2017)·20 citations
4. 04*

   Development of a compact ExB microchannel plate detector for beam imaging

   B. B. Wiggins🇺🇸 · Varinderjit Singh🇺🇸 · J. Vadas🇺🇸 · J. Huston🇺🇸 · T. K. Steinbach · S. Hudan🇺🇸 · R. T. deSouza🇺🇸

   A beam imaging detector was developed by coupling a multi-strip anode with delay line readout to an E$\times$B microchannel plate (MCP) detector. This detector is capable of measuring the incident position of the beam particles in one-dimension. To assess the spatial resolution, the detector was illuminated by an $\alpha$-source with an intervening mask that consists of a series of precisely-machined slits. The measured spatial resolution was 520$\mu$m FWHM, which was improved to 413$\mu$m FWHM by performing an FFT of the signals, rejecting spurious signals on the delay line, and requiring a minimum signal amplitude. This measured spatial resolution of 413$\mu$m FWHM corresponds to an intrinsic resolution of 334$\mu$m FWHM when the effect of the finite slit width is de-convoluted. To understand the measured resolution, the performance of the detector is simulated with the ion-trajectory code SIMION.

   ↳ physics.ins-detnucl-ex0 citations
5. 05*

   Role of Multi-Parton Interactions on $J/\psi$ production in $p+p$ collisions at LHC Energies

   Dhananjaya Thakur🇮🇳 · Sudipan De🇮🇳 · Raghunath Sahoo🇮🇳 · Soumya Dansana🇮🇳

   The production mechanism of quarkonia states in hadronic collisions is still to be understood by the scientific community. In high-multiplicity $p+p$ collisions, Underlying Event (UE) observables are of major interest. The Multi-Parton Interactions (MPI) is a UE observable, where several interactions occur at the partonic level in a single $p+p$ event. This leads to dependence of particle production on event multiplicity. If the MPI occurs in a harder scale, there will be a correlation between the yield of quarkonia and total charged particle multiplicity. The ALICE experiment at the Large Hadron Collider (LHC) in $p+p$ collisions at $\sqrt{s}$ = 7 and 13 TeV has observed an approximate linear increase of relative $J/\psi$ yield ($\frac{d{N}_{J/\psi }/dy}{<d{N}_{J/\psi }/dy>}$) with relative charged particle multiplicity density ($\frac{d{N}_{ch}/dy}{<d{N}_{ch}/dy>}$). In our present work we have performed a comprehensive study of the production of charmonia as a function of charged particle multiplicity in $p+p$ collisions at LHC energies using pQCD-inspired multiparton interaction model, PYTHIA8 tune 4C, with and without Color Reconnection (CR) scheme. A detail multiplicity and energy dependent study is performed to understand the effects of MPI on $J/\psi$ production. The ratio of $\psi (2S)$ to $J/\psi$ is also studied as a function of charged particle multiplicity at LHC energies.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2018)·44 citations
6. 06*

   Hyperfine splitting in ordinary and muonic hydrogen

   Oleksandr Tomalak🇩🇪

   We provide an accurate evaluation of the two-photon exchange correction to the hyperfine splitting of S energy levels in muonic hydrogen exploiting the corresponding measurements in electronic hydrogen. The proton structure uncertainty in the calculation of ${\alpha }^5$ contribution is sizably reduced.

   ↳ hep-phnucl-exnucl-thphysics.atom-phEPJA(2018)·18 citations
7. 07*

   Demonstration of Laser-produced Neutron Diagnostic by Radiative Capture Gamma-rays

   Xiaopeng Zhang · Wenqing Wei · Changbo Fu🇨🇳 · Xiaohui Yuan · Songhai An · Yanqing Deng · Yuan Fang · Jian Gao🇨🇳 · Xulei Ge · Bing Guo · Chuangye He · Peng Hu and 20 other authors

   We report a new scenario of time-of-flight (TOF) technique in which fast neutrons and delayed gamma-ray signals were both recorded in a millisecond time window in harsh environments induced by high-intensity lasers. The delayed gamma signals, arriving far later than the original fast neutron and often being ignored previously, were identified to be the results of radiative captures of thermalized neutrons. The linear correlation between gamma photon number and the fast neutron yield shows that these delayed gamma events can be employed for neutron diagnosis. This method can reduce the detecting efficiency dropping problem caused by prompt high-flux gamma radiation, and provides a new way for neutron diagnosing in high-intensity laser-target interaction experiments.

   ↳ physics.ins-detnucl-exRev.Sci.Instrum.(2018)·0 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.