%0 Generic %1 dawoodbhoy2021coreenvelope %A Dawoodbhoy, Taha %A Shapiro, Paul R. %A Rindler-Daller, Tanja %D 2021 %K tifr %T Core-Envelope Haloes in Scalar Field Dark Matter with Repulsive Self-Interaction: Fluid Dynamics Beyond the de Broglie Wavelength %U http://arxiv.org/abs/2104.07043 %X Scalar Field Dark Matter (SFDM) comprised of ultralight bosons has attracted great interest as an alternative to standard, collisionless Cold Dark Matter (CDM) because of its novel structure-formation dynamics, described by the coupled Schrödinger-Poisson equations. In the free-field ("fuzzy") limit of SFDM (FDM), structure is inhibited below the de Broglie wavelength, but resembles CDM on larger scales. Virialized haloes have "solitonic" cores of radius $\simłambda_deB$, surrounded by CDM-like envelopes. When a strong enough repulsive self-interaction (SI) is also present, structure can be inhibited below a second length scale, $łambda_SI$, with $łambda_SI> łambda_deB$ -- called the Thomas-Fermi (TF) regime. FDM dynamics differs from CDM because of quantum pressure, and SFDM-TF differs further by adding SI pressure. In the small-$łambda_deB$ limit, however, we can model all three by fluid conservation equations for a compressible, $\gamma=5/3$ ideal gas, with ideal gas pressure sourced by internal velocity dispersion and, for the TF regime, an added SI pressure, $P_SI\rho^2$. We use these fluid equations to simulate halo formation from gravitational collapse in 1D, spherical symmetry, demonstrating for the first time that SFDM-TF haloes form with cores the size of $R_TF$, the radius of an SI-pressure-supported $(n=1)$-polytrope, surrounded by CDM-like envelopes. In comparison with rotation curves of dwarf galaxies in the local Universe, SFDM-TF haloes pass the "too-big-to-fail" + "core-cusp"-test if $R_TF1$ kpc.

@misc{dawoodbhoy2021coreenvelope, abstract = {Scalar Field Dark Matter (SFDM) comprised of ultralight bosons has attracted great interest as an alternative to standard, collisionless Cold Dark Matter (CDM) because of its novel structure-formation dynamics, described by the coupled Schr\"odinger-Poisson equations. In the free-field ("fuzzy") limit of SFDM (FDM), structure is inhibited below the de Broglie wavelength, but resembles CDM on larger scales. Virialized haloes have "solitonic" cores of radius $\sim\lambda_\text{deB}$, surrounded by CDM-like envelopes. When a strong enough repulsive self-interaction (SI) is also present, structure can be inhibited below a second length scale, $\lambda_\text{SI}$, with $\lambda_\text{SI}> \lambda_\text{deB}$ -- called the Thomas-Fermi (TF) regime. FDM dynamics differs from CDM because of quantum pressure, and SFDM-TF differs further by adding SI pressure. In the small-$\lambda_\text{deB}$ limit, however, we can model all three by fluid conservation equations for a compressible, $\gamma=5/3$ ideal gas, with ideal gas pressure sourced by internal velocity dispersion and, for the TF regime, an added SI pressure, $P_\text{SI}\propto \rho^2$. We use these fluid equations to simulate halo formation from gravitational collapse in 1D, spherical symmetry, demonstrating for the first time that SFDM-TF haloes form with cores the size of $R_\text{TF}$, the radius of an SI-pressure-supported $(n=1)$-polytrope, surrounded by CDM-like envelopes. In comparison with rotation curves of dwarf galaxies in the local Universe, SFDM-TF haloes pass the ["too-big-to-fail" + "core-cusp"]-test if $R_\text{TF}\gtrsim 1$ kpc.}, added-at = {2021-04-16T06:21:07.000+0200}, author = {Dawoodbhoy, Taha and Shapiro, Paul R. and Rindler-Daller, Tanja}, biburl = {https://www.bibsonomy.org/bibtex/20075163db50c379b2f7c7d4f373bb509/citekhatri}, description = {Core-Envelope Haloes in Scalar Field Dark Matter with Repulsive Self-Interaction: Fluid Dynamics Beyond the de Broglie Wavelength}, interhash = {6b143be439fce1ccc35cb01efc9b2819}, intrahash = {0075163db50c379b2f7c7d4f373bb509}, keywords = {tifr}, note = {cite arxiv:2104.07043Comment: 27 pages, 11 figures, submitted to MNRAS, comments welcome}, timestamp = {2021-04-16T06:21:07.000+0200}, title = {Core-Envelope Haloes in Scalar Field Dark Matter with Repulsive Self-Interaction: Fluid Dynamics Beyond the de Broglie Wavelength}, url = {http://arxiv.org/abs/2104.07043}, year = 2021 }