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Using cosmological particle hydrodynamical simulations and uniform ultraviolet backgrounds, we compare Lyman-$alpha$ forest flux spectra predicted by the conventional cold dark matter (CDM) model, the free-particle wave dark matter (FP$psi$DM) model and extreme-axion wave dark matter (EA$psi$DM) models of different initial axion field angles against the BOSS Lyman-$alpha$ forest absorption spectra with a fixed boson mass $m_bsim 10^{-22}$eV. We recover results reported previously (Irv{s}iv{c} et al. 2017b; Armengaud et al. 2017) that the CDM model agrees better with the BOSS data than the FP$psi$DM model by a large margin, and we find the difference of total $chi^2$s is $120$ for $420$ data bins. These previous results demand a larger boson mass by a factor $>10$ to be consistent with the date and are in tension with the favoured value determined from local satellite galaxies. We however find that such tension is removed as some EA$psi$DM models predict Lyman-$alpha$ flux spectra agreeing better with the BOSS data than the CDM model, and the difference of total $chi^2$s can be as large as $24$ for the same bin number. This finding arises with no surprise since EA$psi$DM models have unique spectral shapes with spectral bumps in excess of the CDM power near the small-scale cutoff typical of $psi$DM linear matter power spectra as well as more extended cutoffs than FP$psi$DM (Zhang & Chiueh 2017a,b).
We present the BOSS Lyman-alpha (Lya) Forest Sample from SDSS Data Release 9, comprising 54,468 quasar spectra with zqso > 2.15 suitable for Lya forest analysis. This data set probes the intergalactic medium with absorption redshifts 2.0 < z_alpha <
We investigate the large-scale structure of Lyman-alpha emission intensity in the Universe at redshifts z=2-3.5 using cross-correlation techniques. Our Lya emission samples are spectra of BOSS Luminous Red Galaxies from Data Release 12 with the best
We present constraints on the masses of extremely light bosons dubbed fuzzy dark matter from Lyman-$alpha$ forest data. Extremely light bosons with a De Broglie wavelength of $sim 1$ kpc have been suggested as dark matter candidates that may resolve
The renewed interest in the possibility that primordial black holes (PBHs) may constitute a significant part of the dark matter has motivated revisiting old observational constraints, as well as developing new ones. We present new limits on the PBH a
With recent Lyman-alpha forest data from BOSS and XQ-100, some studies suggested that the lower mass limit on the fuzzy dark matter (FDM) particles is lifted up to $10^{-21},mathrm{eV}$. However, such a limit was obtained by $Lambda$CDM simulations w