Rotation curves of high-resolution LSB and SPARC galaxies with fuzzy and multistate (ultralight boson) scalar field dark matter

• Published in: Monthly notices of the Royal Astronomical Society Vol. 475; no. 2; pp. 1447 - 1468
• Main Authors: Bernal, T, Fernández-Hernández, L M, Matos, T, Rodríguez-Meza, M A
• Format: Journal Article
• Language: English
• Published: London Oxford University Press 01.04.2018
• Subjects: Computer simulation; Dark matter; Empirical analysis; Galactic evolution; Galactic rotation; Galaxies; High resolution; Surface brightness; Temperature; Universe
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stx3208

AbstractCold dark matter (CDM) has shown to be an excellent candidate for the dark matter (DM) of the Universe at large scales; however, it presents some challenges at the galactic level. The scalar field dark matter (SFDM), also called fuzzy, wave, Bose-Einstein condensate, or ultralight axion DM, is identical to CDM at cosmological scales but different at the galactic ones. SFDM forms core haloes, it has a natural cut-off in its matter power spectrum, and it predicts well-formed galaxies at high redshifts. In this work we reproduce the rotation curves of high-resolution low surface brightness (LSB) and SPARC galaxies with two SFDM profiles: (1) the soliton+NFW profile in the fuzzy DM (FDM) model, arising empirically from cosmological simulations of real, non-interacting scalar field (SF) at zero temperature, and (2) the multistate SFDM (mSFDM) profile, an exact solution to the Einstein-Klein-Gordon equations for a real, self-interacting SF, with finite temperature into the SF potential, introducing several quantum states as a realistic model for an SFDM halo. From the fits with the soliton+NFW profile, we obtained for the boson mass 0.212 < mψ /(10-23 eV/c2 ) < 27.0 and for the core radius 0.326 < rc /kpc < 8.96. From the combined analysis with the LSB galaxies, we obtained mψ = 0.554 × 10-23 eV, a result in tension with the severe cosmological constraints. Also, we show the analytical mSFDM model fits the observations as well as or better than the empirical soliton+NFW profile, and it reproduces naturally the wiggles present in some galaxies, being a theoretically motivated framework additional or alternative to the FDM profile.