scholarly journals The Dark Matter Halo Density Profile, Spiral Arm Morphology, and Supermassive Black Hole Mass of M33

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Marc S. Seigar
Keyword(s):  
Black Hole ◽  
Dark Matter ◽  
Density Profile ◽  
Pitch Angle ◽  
Rotation Curve ◽  
Dark Matter Halo ◽  
Black Hole Mass ◽  
Supermassive Black Hole ◽  
Virial Mass ◽  
Spiral Arm

We investigate the dark matter halo density profile of M33. We find that the HI rotation curve of M33 is best described by an NFW dark matter halo density profile model, with a halo concentration of and a virial mass of . We go on to use the NFW concentration of M33, along with the values derived for other galaxies (as found in the literature), to show that correlates with both spiral arm pitch angle and supermassive black hole mass.

Testing the Correlation between Spiral Arm Pitch Angle and Central Black Hole Mass

2010 ◽  
Author(s):  
Douglas W. Shields ◽  
J. Adam Hughes ◽  
Scott R. Barrows ◽  
Ben Davis ◽  
Daniel Kennefick ◽  
...  
Keyword(s):  
Black Hole ◽  
Pitch Angle ◽  
Black Hole Mass ◽  
Central Black Hole ◽  
Spiral Arm

scholarly journals Fuzzy dark matter soliton cores around supermassive black holes

2020 ◽  
Vol 492 (4) ◽  
pp. 5721-5729 ◽  
Author(s):  
Elliot Y Davies ◽  
Philip Mocz
Keyword(s):  
Black Hole ◽  
Dark Matter ◽  
Density Profile ◽  
Mass Region ◽  
Theoretical Modelling ◽  
Black Hole Mass ◽  
Squeezing Effect ◽  
Mass Measurements ◽  
Poisson Equations ◽  
Large Black Hole

ABSTRACT We explore the effect of a supermassive black hole (SMBH) on the density profile of a fuzzy dark matter (FDM) soliton core at the centre of a dark matter (DM) halo. We numerically solve the Schrödinger–Poisson equations, treating the black hole as a gravitational point mass, and demonstrate that this additional perturbing term has a ‘squeezing’ effect on the soliton density profile, decreasing the core radius, and increasing the central density. In the limit of large black hole mass, the solution approaches one akin to the hydrogen atom, with radius inversely proportional to the black hole mass. By applying our analysis to two specific galaxies (M87 and the Milky Way) and pairing it with known observational limits on the amount of centrally concentrated DM, we obtain a constraint on the FDM particle mass, finding that the range 10−22.12 eV ≲ m ≲ 10−22.06 eV should be forbidden (taking into account additional factors concerning the lifetime of the soliton in the vicinity of a black hole). Improved observational mass measurements of the black hole and total enclosed masses will significantly extend the lower bound on the excluded FDM mass region, while self-consistent theoretical modelling of the soliton–black hole system can extend the upper bound.

scholarly journals Explaining the density profile of self-gravitating systems by statistical mechanics

2015 ◽  
Vol 11 (A29B) ◽  
pp. 743-743
Author(s):  
Dong-Biao Kang
Keyword(s):  
Dark Matter ◽  
Angular Momentum ◽  
Radial Distribution ◽  
Density Profile ◽  
Large Scale ◽  
Rotation Curve ◽  
Dark Matter Halo ◽  
Stellar Disk ◽  
Exponential Law ◽  
Flat Rotation Curve

AbstractA self-gravitating system usually shows a quasi-universal density profile, such as the NFW profile of a simulated dark matter halo, the flat rotation curve of a spiral galaxy, the Sérsic profile of an elliptical galaxy, the King profile of a globular cluster and the exponential law of the stellar disk. It will be interesting if all of the above can be obtained from first principles. Based on the original work of White & Narayan (1987), we propose that if the self-bounded system is divided into infinite infinitesimal subsystems, the entropy of each subsystem can be maximized, but the whole system's gravity may just play the role of the wall, which may not increase the whole system's entropy St, and finally St may be the minimum among all of the locally maximized entropies (He & Kang 2010). For spherical systems with isotropic velocity dispersion, the form of the equation of state will be a hybrid of isothermal and adiabatic (Kang & He 2011). Hence this density profile can be approximated by a truncated isothermal sphere, which means that the total mass must be finite and our results can be consistent with observations (Kang & He 2011b). Our method requires that the mass and energy should be conserved, so we only compare our results with simulations of mild relaxation (i.e. the virial ratio is close to -1) of dissipationless collapse (Kang 2014), and the fitting also is well. The capacity can be calculated and is found not to be always negative as in previous works, and combining with calculations of the second order variation of the entropy, we find that the thermodynamical stability still can be true (Kang 2012) if the temperature tends to be zero. However, the cusp in the center of dark matter halos can not be explained, and more works will continue.The above work can be generalized to study the radial distribution of the disk (Kang 2015). The energy constraint automatically disappears in our variation, because angular momentum is much more important than energy for the disk-shape system. To simplify this issue, a toy model is taken: 2D gravity is adopted, then at large scale it will be consistent with a flat rotation curve; the bulge and the stellar disk are studied together. Then with constraints of mass and angular momentum, the calculated surface density can be consistent with the truncated, up-bended or standard exponential law. Therefore the radial distribution of the stellar disk may be determined by both the random and orbital motions of stars. In our fittings the central gravity is set to be nonzero to include the effect of asymmetric components.

scholarly journals FURTHER EVIDENCE FOR A SUPERMASSIVE BLACK HOLE MASS-PITCH ANGLE RELATION

2013 ◽  
Vol 769 (2) ◽  
pp. 132 ◽  
Author(s):  
Joel C. Berrier ◽  
Benjamin L. Davis ◽  
Daniel Kennefick ◽  
Julia D. Kennefick ◽  
Marc S. Seigar ◽  
...  
Keyword(s):  
Black Hole ◽  
Pitch Angle ◽  
Black Hole Mass ◽  
Supermassive Black Hole

scholarly journals Galaxy Bulge Formation: Interplay with Dark Matter Halo and Central Supermassive Black Hole

2007 ◽  
Vol 664 (1) ◽  
pp. 198-203 ◽  
Author(s):  
Bing‐Xiao Xu ◽  
Xue‐Bing Wu ◽  
Hong‐Sheng Zhao
Keyword(s):  
Black Hole ◽  
Dark Matter ◽  
Dark Matter Halo ◽  
Supermassive Black Hole ◽  
Bulge Formation

scholarly journals SIMPLE FIT OF DATA RELATING SUPERMASSIVE BLACK HOLE MASS TO GALAXY PITCH ANGLE

2009 ◽  
Vol 137 (6) ◽  
pp. 4716-4717 ◽  
Author(s):  
Harry I. Ringermacher ◽  
Lawrence R. Mead
Keyword(s):  
Black Hole ◽  
Pitch Angle ◽  
Black Hole Mass ◽  
Supermassive Black Hole
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