Supermassive Dark Stars Detectable by Roman Space Telescope and James Webb Space Telescope with Lensing

Dark stars are luminous stellar objects powered by dark matter annihilation and can grow supermassive to ~10^6M⊙ via accretion. In this study, we investigate various methods for the detection of supermassive dark stars(SMDS) by the James Webb Space Telescope(JWST) and Roman Space Telescope(RST) . JWST has higher light sensitivity and a more extensive wavelength range, while the RST will provide a much wider effective field of view that increases the probability of detection. Similar to JWST, RST will also detect J- and H- band dropouts if SMDS ever exists at the redshift of ~10 and 12. To differentiate SMDS from objects like Pop.III galaxies at similar redshift, we compare their color indexes using the spectral energy distribution simulations. We find that to make them differentiable, at least a signal-to-noise ratio(SNR) of 50 will be needed, which can be achieved by long exposure(~10^6s) or some lensing magnification(~100) . The lensing effect will also allow us to detect SMDS of smaller mass(~10^5M⊙) by simulation. If SMDS is detected, this will provide evidence for WIMP dark matter. Such massive stars can also be the progenitor of supermassive black holes observed at early times.