Neutrino mass and Gravitational waves from first order phase transitions

主讲人 (Speaker): 
Andrea Addazi
主讲人单位 (Speaker's Institute): 
邀请人 (Invited by): 
黄志琦 (Zhiqi Huang)
时间 (Time): 
星期二, 2017/06/06 - 10:30 to 11:30
地点 (Location): 
摘要 (Abstract): 

We show how Majoron models may be tested/limited in gravitational waves experiments. In particular, the Majoron self-interaction potential may induce a first order phase transition, producing gravitational waves from bubble collisions. We dubbed such a new scenario {\it violent Majoron model}, because it would be associated to a violent phase transition in the early Universe. Sphaleron constraints can be avoided if the global $U(1)_{B-L}$ is broken at scales lower than the electroweak scale, provided that the B-L spontaneously breaking scale is lower than $10\, {\rm TeV}$ in order to satisfy the cosmological mass density bound. The possibility of a sub-electroweak phase transition is practically unconstrained by cosmological bounds and it may be detected within the sensitivity of next generation of gravitational waves experiments: eLISA, DECIGO and BBO. We also comment on the possible detection in CEPC collider, where Majorons's production can be observed from Higgs' portals in missing transverse energy channels.

主讲人简介 (Speaker's CV): 
Andrea Addazi在意大利的Università degli Studi dell'Aquila获得博士学位。现在是复旦大学物理系的博士后。他的研究兴趣包括中微子模型,超弦,粒子宇宙学,引力波等。迄今在SCI刊物上发表多篇论文。