Probing parity-odd bispectra with anisotropies of GW $V$ modes

Understand

It is well known that non-trivial squeezed tensor bispectra can lead to anisotropies in the inflationary stochastic gravitational wave (GW) background, providing us with an alternative and complementary window to primordial non-Gaussianities (NGs) with respect to the CMB.

• Previous works have highlighted the detection prospects of parity-even tensor NGs via the GW $I$-mode anisotropies.
• In this work we extend this by analysing for the first time the additional information carried by GW $V$-mode anisotropies due to squeezed NGs.
• We show that GW $V$ modes allow us to probe parity-odd squeezed $\langle \rm tts \rangle$ and $\langle \rm ttt \rangle$ bispectra.