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Direct mass measurements of neutron-deficient nuclides around the N=50 shell closure below 100Sn were performed at the FRS Ion Catcher (FRS-IC) at GSI, Germany. The nuclei were produced by projectile fragmentation of 124Xe, separated in the fragment separator FRS and delivered to the FRS-IC. The masses of 14 ground states and two isomers were measured with relative mass uncertainties down to 1×10−7 using the multiple-reflection time-of-flight mass spectrometer of the FRS-IC, including the first direct mass measurements of 98Cd and 97Rh. A new QEC=5437±67 keV was obtained for 98Cd, resulting in a summed Gamow-Teller (GT) strength for the five observed transitions (0+⟶1+) as B(GT)=2.94−0.28+0.32. Investigation of this result in state-of-the-art shell model approaches accounting for the first time experimentally observed spectrum of GT transitions points to a perfect agreement for N=50 isotones. The excitation energy of the long-lived isomeric state in 94Rh was determined for the first time to be 293±21 keV. This, together with the shell model calculations, allows the level ordering in 94Rh to be understood.

A compact ion source combining electron impact and thermal ionization has been developed and commissioned in two Multiple-Reflection Time-Of-Flight Mass Spectrometer (MR-TOF-MS) setups at the Fragment Separator Ion Catcher at the GSI Helmholtz Centre for Heavy Ion Research, Darmstadt, Germany, and at TRIUMF's Ion Trap for Atomic and Nuclear science at TRIUMF Canada's particle accelerator center, Vancouver, Canada. The ion source is notable for its compact dimensions of 50 mm in height and 68 mm in diameter. The ion source is currently in daily operation at both facilities. Design, simulations, and results of combining ions from thermal and electron-impact ionization of different gases (perfluoropropane and sulfur hexafluoride) are presented in this work. The systematic effects of heating power on the thermal source were studied in detail. The source has demonstrated stable and long-term production of reference ions over a wide mass range for the MR-TOF-MS. This versatile ion source has also been used to optimize and investigate the transport of ions with different chemical reactivity and ionization potentials. [ABSTRACT FROM AUTHOR]

We present a direct method to measure fission product yield distributions (FPY) and isomeric yield ratios (IYR) for spontaneous fission (SF) fragments. These physical properties are of utmost importance to the understanding of basic nuclear physics, the astrophysical rapid neutron capture process ('r process') of nucleosynthesis, neutron star composition, and nuclear reactor safety. With this method, fission fragments are produced by spontaneous fission from a source that is mounted in a cryogenic stopping cell (CSC), thermalized and stopped within it, and then extracted and transported to a multiple-reflection time-of-flight mass-spectrometer (MR-TOF-MS). We will implement the method at the FRS Ion Catcher (FRS-IC) at GSI (Germany), whose MR-TOF-MS relative mass accuracy (~ 10-7) and resolving power (~ 600,000 FWHM) are sufficient to separate all isobars and numerous isomers in the fission fragment realm. The system's essential element independence and its fast simultaneous mass measurement provide a new direct way to measure isotopic FPY distributions, which is complementary to existing methods. It will enable nuclide FPY measurements in the high fission peak, which is hardly accessible by current techniques. The extraction time of the CSC, tens of milliseconds, enables a direct measurement of independent fission yields, and a first study of the temporal dependence of FPY distributions in this duration range. The ability to resolve isomers will further enable direct extraction of numerous IYRs while performing the FPY measurements. The method has been recently demonstrated at the FRS-ICr for SF with a 37 kBq 252Cf fission source, where about 70 different fission fragments have been identified and counted. In the near future, it will be used for systematic studies of SF with a higher-activity 252Cf source and a 248Cm source. The method can be implemented also for neutron induced fission at appropriate facilities.

In a sociological review of novels, the connection between structure and content of the story studied by considering the conditions and changes in society and environment in which they are created, and the modality of artistic reflection of the society in the world of the literary work is reviewed and analyzed. In this article, the authors present an analysis of the works of the famous Algerian female novelist called “Ahlam Mosteghanemi”. As a writer, she is romantic, but she deals with social and cultural situation in her country relying on community-oriented romanticism. She deals with many issues such as women’s rights, cultural poverty, social instability and conflict between tradition and modernity, and also describes the wounds and injuries imposed on the society through the colonialism. Based on the results obtained from this descriptive- analytical research, we come to realize that she could open a horizon to knowing different angles of occupation in Algeria, liberation wars at this country, results of colonization and mustiness of Arab communities. She also tries to keep her obligation to romanticism, using an emotional tone. Although her works have a critic tone, they are drastically different social realism.

Palestinian women have not only collaborated with men in issues such as social, political and cultural affairs but also in literary fields. They have even been pioneer in some fields. A number of senses of contemporary Palestinian poetries have been considered by both genders which include different types of sentimental poetries such as ghazals and love poems. Although ghazal has been among the most important types of Palestinian poetry for long, there are certain differences between female ghazals and the male ones, which is an indication of physical and psychological differences between them. This research tries to study those differences and to find out the reasons. The research methods have been documentary and library methods. As a result women, in their poems, pay less attention to physical and beauty attractions in their love poems. Instead, sentimental symbols have been considered by female poets and they use more codes and metaphors compared to male poets.

If we study the contemporary Palestinian poetry of the last century we will find that the theme of nationhood and motherland dominates it. One reason is the fact that during this period Palestine has been through such events that has ignited a sense of patriotism, a wish to defend of the motherland and the Arabic origin of the Palestinian people. Since the Balfour Declaration, the endeavour to enforce it and the repression of the Paletinians during the uprisings of 1936-1948, and especially after the 1967 war, have contributed to the cause of Palestinian nationalism. It is natural therefore that contemporary Palestinian poetry should be in tune with popular aspirations in promoting the spirit of patriotism

Nuclear mass is a key property of atomic nuclei. The accurate determination of nuclear masses provides information for the nuclear shell structure and nuclear deformations. The FRS Ion Catcher experimental setup at GSI, Darmstadt was used to perform mass measurements of 252Cf fragments using a multiple-reflection time-of-flight mass spectrometer. The reported results are compared to previous measurements and their implication in the estimation of two-neutron separation energy is discussed. [ABSTRACT FROM AUTHOR]

Neutron-deficient iodine isotopes, 116 I and 114 I, were produced at relativistic energies by in-flight fragmentation at the Fragment Separator (FRS) at GSI. The FRS Ion Catcher was used to thermalize the ions and to perform highly accurate mass measurements with a Multiple-Reflection Time-of-Flight Mass-Spectrometer (MR-TOF-MS). The masses of both isotopes were measured directly for the first time. The half-life of the 114 I was measured by storing the ions in an RF quadrupole for different storage times and counting the remaining nuclei with the MR-TOF-MS. The measured half-life was used to assign the ground state to the measured 114 I ions. Predictions on the possible α -decay branch for 114 I are presented based on the reduced uncertainties obtained for the Q α -value. Systematic studies of the mass surface were performed with the newly obtained masses, showing better agreement with the expected trend in this mass region. [ABSTRACT FROM AUTHOR]