The Dark Ages' 21-cm trispectrum

Abstract We investigate tomography of 21-cm brightness temperature fluctuations during the Dark Ages as a probe for constraining primordial non-Gaussianity. expand up to cubic order in perturbation theory and improve previous models signal by including effect free electron fraction. Using modified standard methods that include baryonic pressure effects we derive an improved secondary bispectrum first time trispectrum fluctuations. then forecast amount information available from constrain non-Gaussianity, imprints massive particle exchange inflation determine how much is lost due find although non-Gaussianity swamps signal, can still be extracted with signal-to-noise ratios surpass current future CMB experiments several orders magnitude, depending on experimental setup. Furthermore, conclude bi- trispectra marginalizing over other shapes affects more severely than shapes. Baryonic turn out have negligible impact our forecasts, even at scales close Jeans scale. The results this work reinforce prospects ultimate