Wed·Sep 18, 2019Wednesday·September 18, 2019

1. 01*

   Recent Results of the Majorana Demonstrator Experiment

   J.M.López-Castaño

   The MAJORANA DEMONSTRATOR is searching for neutrinoless double-beta decay in ${}^{76}$Ge with two modular arrays of natural and ${}^{76}$Ge-enriched germanium detectors. It is located at the 4850 level of Sanford Underground Research Facility in Lead, South Dakota, USA, and its total mass of germanium detectors is 44.1 kg, of which 29.7 kg is enriched. The analysis of the first 26 kg-yr of data provides an unprecedented energy resolution of 0.13% in the region of interest at 2039 keV and a background level of 15.4 $\pm$ 2.0 counts/(FWHM t yr). It establishes the lower limit of the half-life of neutrinoless double beta decay as 2.7 10${}^{25}$ yr in 76Ge at 90% CL. This analysis will be summarized here with an emphasis on the energy determination.

   ↳ hep-exnucl-exphysics.ins-detAIP Conf.Proc.(2019)·3 citations
2. 02*

   Production of $\varphi (2170)$ and $\eta (2225)$ in a kaon induced reaction

   Xiao-Yun Wang🇨🇳 · Jun He🇨🇳

   In this work, we study the production of strange quarkoniums, the $\varphi (2170)$, also named $Y(2175)$, and the $\eta (2225)$, via a kaon induced reaction on a proton target in an effective Lagrangian approach. The total and differential cross sections of the reactions $K^{-}p\to \varphi (2170)\Lambda$ and $K^{-}p\to \eta (2225)\Lambda$ are calculated by the Reggeized $t$-channel Born term under an assumption that the $\varphi (2170)$ and $\eta (2225)$ are $\Lambda \bar{\Lambda }$ molecular states. At the center of mass energies of about 4.2 GeV, the total cross section for the $\varphi (2170)$ production is predicted to be about 1 $\mu$b. The numerical results indicate that it is feasible to produce the $\varphi (2170)$ via kaon beam scattering at the best energy window near 4.2 GeV. The total cross section for the $\eta (2225)$ production is smaller than that for the $\varphi (2170)$ production and it may reach an order of the magnitude of 0.1 $\mu$b. The differential cross sections for both reactions at different center of mass energies are also presented. It is found that the Reggeized $t$ channel gives a considerable contribution at forward angles. As the energy increases, the contribution from the $t$-channel almost concentrates at extreme forward angles. From these theoretical predictions, the relevant experimental research is suggested, which could provide important information to clarify the internal structure and production mechanism of these two strange quarkoniums.

   ↳ nucl-thhep-phnucl-exEPJA(2019)·14 citations
3. 03*

   Microscopic study of strange hadron productions at the LHC with$\sqrt{s_{NN}}$=2.76 TeV

   Purabi Ghosh🇮🇳 · Jajati K. Nayak🇮🇳 · Sushant K. Singh🇮🇳 · Santosh K. Agarwalla🇮🇳

   Ratio of the yield of strange hadrons to pions is considered as an important observable in studying the properties of the system produced in relativistic heavy ion collisions. Production of strange hadrons $K,\bar{K},\Lambda ,\Sigma ,\Xi$ and $\Omega$ have been evaluated microscopically using rate equations by considering their hadronic interaction cross sections in an expanding medium. The yields obtained from rate equations are normalized with thermal pions and compared with the measurements from Pb-Pb collisions at various multiplicities at LHC energy. The calculation has been done for various initial and freeze out conditions. At 2760 GeV, LHC energy, $\Lambda ,\Xi ,\Omega$ freeze out close to $T_C$ and $K_s^0$ freezes out little later. But there is a subtle difference in freeze out temperatures of different species which may be distinguishable at lower colliding energies.

   ↳ nucl-thhep-exhep-phnucl-exPRD(2020)·7 citations
4. 04*

   The Shape of the Correlation Function

   Jakub Cimerman🇨🇿 · Christopher Plumberg🇸🇪 · Boris Tomášik🇸🇰

   The two-particle correlation function employed in Hanbury-Brown Twiss interferometry and femtoscopy is traditionally parameterized by a Gaussian form. Other forms, however, have also been used, including the somewhat more general Lévy form. Here we consider a variety of effects present in realistic femtoscopic studies which may modify the shape of the correlation function and thereby influence the physical interpretation of a given parameterization.

   ↳ nucl-thhep-phnucl-exPhys.Part.Nucl.(2020)·8 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.