The new interaction suggested by the anomalous 8^8Be transition sets a rigorous constraint on the mass range of dark matter

The WIMPs are considered one of the favorable dark matter (DM) candidates, but as the upper bounds on the interactions between DM and standard model (SM) particles obtained by the upgraded facilities of DM direct detections get lower and lower. Researchers turn their attentions to search for less massive DM candidates, i.e. light dark matter of MeV scale. The recently measured anomalous transition in $^8$Be suggests that there exists a vectorial boson which may mediate the interaction between DM and SM particles. Based on this scenario, we combine the relevant cosmological data to constrain the mass range of DM, and have found that there exists a model parameter space where the requirements are satisfied, a range of $10.4 \lesssim m_{\phi} \lesssim$ 16.7 MeV for scalar DM, and $13.6 \lesssim m_{V} \lesssim$ 16.7 MeV for vectorial DM is demanded. Then a possibility of directly detecting such light DM particles via the DM-electron scattering is briefly studied in this framework.Comment: 13 Pages, 7 figures, references added, version accepted by journa

The Organizational Operation of Farmers’ Specialized Technology Association (FSTA) in Yuanshi County Hebei Province

This paper examines NPO, a FSTA in Yushi County Hebei Province, focusing its organizational operation and evolvement process of property right system. The paper found that evolvement of property rights system is experiencing a ‘Cooperative System →Joint Stock Cooperative System → Joint Stock System’ process. Other newly established associations might replace the previous functions of mutual aid and service. Key words: Organizational Framework, Organizational Operation, Property Rights System Résumé: Cet essai examine une organisation non lucrative, un FSTA dans la région Yuxi de la province du Hubei, se concentrant sur son opération organisationnelle et l’évolution de son système du droit de propriété. L’essai trouve que l’évolution du système du droit de propriété connaît un tel processus : Système coopératif→ Système coopératif de stock joint→ Système de stock joint. D’autres associations dernièremment établies pourraient remplacer les fonctions précédentes d’aide mutuelle et de service. Mots-Clés: cadre organisationnel, opération organisationnelle, système du droit de propriét

Truth-telling with a smartphone: The effect of communication media in strategic interactions

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