Hydrodynamic simulations of the triaxial bulge of M 31
Citations
737 citations
Cites background from "Hydrodynamic simulations of the tri..."
...Those anomalies are attributed to the presence of a triaxial bar/bulge in M31 (e.g. Stark 1977; Stark & Binney 1994; Berman 2001)....
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198 citations
Cites background from "Hydrodynamic simulations of the tri..."
...The location of these spots and appearance of the nuclear region (especially at 70 µm) is similar to the triaxial bulge simulations of Berman (2001)....
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193 citations
Cites background from "Hydrodynamic simulations of the tri..."
...Its non-circular orbit may be caused by the central bar (Berman 2001; Berman & Loinard 2002)....
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175 citations
Cites background from "Hydrodynamic simulations of the tri..."
...However, notice that this is shown not just to point out the consistency of the molecular and atomic gas velocities, but to emphasize one has to consider non-circular motion to properly trace the rotation curve in the inner region (Berman 2001; Berman & Loinard 2002)....
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...In particular Berman (2001); Berman & Loinard (2002) have shown that the anomalous velocities observed in the inner region of M31 can be explained as the response of the gas to the potential of a triaxial rotating bulge....
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...Detailed modelling of the surface brightness shows that at very least the bulge is an obl te spheroid with axis ratio of 0.8 (Kent 1983) but most likely it is a triaxial bulge (e.g. Berman 2001, and references therein)....
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...Hydrodynamic simulations of the triaxial bulge of M31 by Berman (2001) found a B-band mass-to-light ratio of 6.5 for the bulge i.e. a stellar mass of 1010 M⊙....
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References
9,729 citations
"Hydrodynamic simulations of the tri..." refers background or methods in this paper
...Hence, for a given value of Hubble’s constant, the halo circular speed curve is fully specified byv200 and c. Navarro et al. (1997) find a relationship between the characteristic density and radius (or, equivalently, betweenc andv200) of a halo in a given cosmology, thereby reducing the NFW…...
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...If v200 = v0 = 257 km s−1, then the method of Navarro et al. (1997) gives a halo mass fraction at 3.5 kpc of 58% and a disk mass of only 5.8× 109M ....
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...From Navarro et al. (1997), at a redshiftz = 0, r200 = ( h v200 km s−1 ) kpc....
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7,622 citations
"Hydrodynamic simulations of the tri..." refers background or methods or result in this paper
...One method of breaking this degeneracy is to represent the halo by an NFW profile (Navarro et al. 1996) derived from cosmologicalN -body simulations, ρ(r) ρs = 1 (r/rs)(1 + r/rs)2 , where ρs is a characteristic density,rs = r200/c is a characteristic radius andc is a dimensionless concentration…...
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...This is in stark contrast to the predictions of Navarro et al. (1996), which imply that the halo mass fraction within 3.5 kpc is between 44% and 58%....
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...However, Navarro et al. (1996) state that the maximum rotation velocity can be as high as1....
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1,025 citations
"Hydrodynamic simulations of the tri..." refers methods in this paper
...Using the values ofAB = 0.32 mag for our Galaxy in the direction of M31 (Burstein and Heiles 1982),AB = 0.98 mag for the bulge region of M31 (van Genderen 1973) andM B = 5.48 for the absoluteB-band solar magnitude (Allen 1973), the value of Ie = 22.2 mag arcsec−2 in Walterbos and Kennicutt (1988)…...
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...…of inner isophotes∗ β 1.54 Bulge to disk isophote angle∗∗ ψ 10◦ Max. bulge isophote semi-major axis§ rmax 11′.4 At the distance of M31,1′ = 200 pc on the major axis † Hodge (1992),∗ Walterbos and Kennicutt (1988) ‡ Burstein and Heiles (1982) and van Genderen (1973) ∗∗ Lindblad (1956),§ Stark (1977)...
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946 citations
"Hydrodynamic simulations of the tri..." refers background or methods in this paper
...Athanassoula (1992) shows that these shocks are intimately linked to the dust lanes which appear in many barred galaxies....
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...However, unlike the galaxy models of Athanassoula (1992), M31 is a real galaxy, modelled with a somewhat arbitrary bulge edge....
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...…α 0.3 pc2M−1 yr −1 Initial gas density Σ0 1M pc−2 Constant mass radius rM 10 kpc Sound speed‡ cg 10 km s−1 Galaxy radius rG 10 kpc Courant number C 0.5 † Athanassoula (1992),‡ Cowie (1980) Simulations start with the gas at a uniform surface density Σ0 = 1 M pc−2 and on circular orbits at…...
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...As in Athanassoula (1992), GALAHAD includes a routine to compensate for this by crudely simulating the interaction of stars with the ISM: star formation occurs and gas is removed in areas of high density, whereas stellar mass loss is assumed to take place at a steady rate across the galaxy....
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...Following Athanassoula (1992), we set rco = R a, wherea is the length of the bulge semi-major axis....
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663 citations