2016/07/07 by Federico Lelli, Stacy S. McGaugh, Stacy McGaugh +2 · 1 citation
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Brightness #Dark matter #Disc #Elliptical galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Galaxy rotation curve #Lenticular galaxy #Peculiar galaxy #Photometry (optics) #Physics #Star formation #Stars #Stellar mass #Stellar, planetary, and galactic studies #Surface brightness #Surface brightness fluctuation #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.3847/2041-8205/827/1/l19
Accepted for publication in ApJL (6 pages, 3 figures)
arxiv created 2016/07/07 · openalex publication_date 2016/08/09 · arxiv updated 2016/08/17 · openalex created_date 2016/09/16 · openalex updated_date 2026/08/05
ABSTRACT We use the Spitzer Photometry and Accurate Rotation Curves (SPARC) database to study the relation between the central surface density of stars <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">Σ</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⋆</mml:mo> </mml:mrow> </mml:msub> <mml:mo stretchy="true">(</mml:mo> <mml:mn>0</mml:mn> <mml:mo stretchy="true">)</mml:mo> </mml:math> and dynamical mass <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">Σ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">dyn</mml:mi> </mml:mrow> </mml:msub> <mml:mo stretchy="true">(</mml:mo> <mml:mn>0</mml:mn> <mml:mo stretchy="true">)</mml:mo> </mml:math> in 135 disk galaxies (S0 to dIrr). We find that <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">Σ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">dyn</mml:mi> </mml:mrow> </mml:msub> <mml:mo stretchy="true">(</mml:mo> <mml:mn>0</mml:mn> <mml:mo stretchy="true">)</mml:mo> </mml:math> correlates tightly with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">Σ</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⋆</mml:mo> </mml:mrow> </mml:msub> <mml:mo stretchy="true">(</mml:mo> <mml:mn>0</mml:mn> <mml:mo stretchy="true">)</mml:mo> </mml:math> over 4 dex. This central density relation can be described by a double power law. High surface brightness galaxies are consistent with a 1:1 relation, suggesting that they are self-gravitating and baryon dominated in the inner parts. Low surface brightness (LSB) galaxies systematically deviate from the 1:1 line, indicating that the dark matter contribution progressively increases but remains tightly coupled to the stellar one. The observed scatter is small (∼0.2 dex) and largely driven by observational uncertainties. The residuals show no correlations with other galaxy properties like stellar mass, size, or gas fraction.