Talk detail

Participant	Ito, Asuka
Institution	Kobe University - 1-1, Rokko dai-cho, Nada-ku - Kobe - Hyogo - Japan

Session	GW1	Accepted		Order	Time
Talk	Oral abstract	Title	A strategy for detecting the bispectrum of stochastic gravitational waves
Coauthors
Abstract	Bispectra of primordial gravitational waves is one of the keys to probe the early universe which contain information beyond standard model. In this talk, I give a method to detect bispectra of stochastic gravitational waves. In general, bispectra form a momentum triangle because of homogeneity of the universe. I show that an optimal filter function enables us to extract a specific configuration of the momentum triangle from the correlation of the signals. Applying this method to pulsar timing array gravitational wave detector, I argue about the dependance of positions of three pulsars to the sensitivity, which is called overlap reduction function in the case of power spectra. Our result suggests the optimal positions of pulsars to detect the bispectrum forming a momentum triangle. This study is in preparation to submit and will be published until MG15.
Pdf file

Session	EU2C	Accepted		Order	Time
Talk	Oral abstract	Title	Primordial gravitational waves in an bouncing universe
Coauthors
Abstract	Both inflationary and bouncing scenarios can account for the origin of the large scale structure of the universe. It is often said that detecting primordial gravitational waves is the key to distinguish both scenarios. I show that this is not true if the magnetic field, which existence is inferred by gamma-ray burst observations, was produced in an bouncing scenario. In fact, such magnetic field production can induce abundant primordial gravitational waves. This work has been published in Phys.Lett. B771 (2017) (arXiv:1607.07062).
Pdf file