Graphics: Upper Limits on the Tensor to Scalar Power Ratio

A measurement of the tensor to scalar power ratio, r, would constrain the energy scale of inflation. There is no detection at present, but recent limits on r, evaluated at a pivot scale of 0.05 Mpc-1, are shown in the following plot. This graphic is not intended to illustrate a complete history, but rather provides a snapshot of current upper limits as experiments continue to search for a detection. Please acknowledge LAMBDA when using these images.


Planck PR4 + BK18 + lens + BAO (2022b) (arXiv, ADS)

Planck PR4 + BK18 + lens + BAO (2022a) (arXiv, ADS)

BK18 + WMAP + Planck PR4 (2021) (arXiv, ADS)

Planck PR4 + BK15 (2020) (arXiv, ADS)
Planck PR4, TT+EE+EB+BB (2020)
Planck PR4, TT only (2020)

Planck PR3 + BK15 (2020) (arXiv, ADS)

BK15 (2018) (arXiv, ADS)

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