Polymer Brushes

Yoshizawa, Masahiro; Ohno, Hiroyuki

doi:10.1002/0471762512.ch31

Cited by 11 publications

(9 citation statements)

References 18 publications

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“…This is consistent with the quantitative studies ofGraham & Worley (2008) and largely driven by the changing bulge flux with spiral galaxy type(Yoshizawa & Wakamatsu 1975, , their Figures 1 and 2).…”

supporting

confidence: 92%

Black Hole Mass Scaling Relations for Spiral Galaxies. II. M_BH–M_,tot and M_BH–M_,disk

Davis

Graham

Cameron

2018

ApJ

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Black hole mass (M BH ) scaling relations are typically derived using the properties of a galaxy's bulge and samples dominated by (high-mass) early-type galaxies. Studying late-type galaxies should provide greater insight into the mutual growth of black holes and galaxies in more gas-rich environments. We have used 40 spiral galaxies to establish how M BH scales with both the total stellar mass (M * ,tot ) and the disk's stellar mass, having measured the spheroid (bulge) stellar mass (M * ,sph ) and presented the M BH -M * ,sph relation in Paper I. The relation involving M * ,tot may be beneficial for estimating M BH either from pipeline data or at higher redshift, conditions that are not ideal for the accurate isolation of the bulge. A symmetric Bayesian analysis finds log (M BH /M ) = 3.05 +0.57 −0.49 log M * ,tot /[υ(6.37 × 10 10 M )] + (7.25 +0.13 −0.14 ). The scatter from the regression of M BH on M * ,tot is 0.66 dex; compare 0.56 dex for M BH on M * ,sph and 0.57 dex for M BH on σ * . The slope is > 2 times that obtained using core-Sérsic early-type galaxies, echoing a similar result involving M * ,sph , and supporting a varied growth mechanism among different morphological types. This steeper relation has consequences for galaxy/black hole formation theories, simulations, and predicting black hole masses. We caution that (i) an M BH -M * ,tot relation built from a mixture of early-and late-type galaxies will find an arbitrary slope of approximately 1-3, with no physical meaning beyond one's sample selection, and (ii) evolutionary studies of the M BH -M * ,tot relation need to be mindful of the galaxy types included at each epoch. We additionally update the M * ,tot -(face-on spiral arm pitch angle) relation. 1 We shall use the terms "spheroid" and "bulge" interchangeably.3 Defined by the geometric mean √ ab, where a and b are the major-and minor-axis lengths of a given isophote, respectively; the "equivalent axis" can be considered equivalent to a circle of the same radius. 4 We corrected for Galactic extinction, cosmological redshift dimming, and K-corrections, in addition to dust (see Paper I).

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supporting

confidence: 92%

Black Hole Mass Scaling Relations for Spiral Galaxies. II. M_BH–M_,tot and M_BH–M_,disk

Davis

Graham

Cameron

2018

ApJ

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“…5 (e.g. Trujillo et al 2002;Scannapieco & Tissera 2003;Balcells et al 2007) reflect the results in Yoshizawa & Wakamatsu (1975, their figs 1 and 2) and echo the remarks in Ostriker (1977) and Meisels & Ostriker (1984) that the bulge luminosity, and ergo mass, may be a key parameter which distinguishes galaxies. In Fig.…”

Section: The Bulge-to-disc Flux Ratiosupporting

confidence: 69%

Inclination- and dust-corrected galaxy parameters: bulge-to-disc ratios and size-luminosity relations

Graham¹,

Worley²

2008

Monthly Notices of the Royal Astronomical Society

324

372

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While galactic bulges may contain no significant dust of their own, the dust within galaxy discs can strongly attenuate the light from their embedded bulges. Furthermore, such dust inhibits the ability of observationally determined inclination corrections to recover intrinsic (i.e. dust‐free) galaxy parameters. Using the sophisticated 3D radiative transfer model of Popescu et al. and Tuffs et al., together with the recent determination of the average face‐on opacity by Driver et al. in nearby disc galaxies, we provide simple equations to correct (observed) disc central surface brightness and scalelengths for the effects of both inclination and dust in the B, V, I, J and K passbands. We then collate and homogenize various literature data sets and determine the typical intrinsic scalelengths, central surface brightness and magnitudes of galaxy discs as a function of morphological type. All galaxies have been carefully modelled in their respective papers with a Sérsic R1/n bulge plus an exponential disc. Using the bulge magnitude corrections from Driver et al., we additionally derive the average, dust‐corrected, bulge‐to‐disc flux ratio as a function of galaxy type. With values typically less than 1/3, this places somewhat uncomfortable constraints on some current semi‐analytic simulations. Typical bulge sizes, profile shapes, surface brightness and deprojected densities are provided. Finally, given the two‐component nature of disc galaxies, we present luminosity–size and (surface brightness)–size diagrams for discs and bulges. We also show that the distribution of elliptical galaxies in the luminosity–size diagram is not linear but strongly curved.

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“…If real, this could potentially explain previous findings in the literature of the dependence of the pitch and the bulge mass (e.g. Yoshizawa & Wakamatsu 1975), given the known scaling relation between central black holes and bulges (e.g. Kormendy & Richstone 1995).…”

Section: Observational Constraints On Spiral Formation: Pitch Angle Amentioning

confidence: 65%

The shapes of spiral arms in the S⁴G survey and their connection with stellar bars

Díaz-García¹,

Salo²,

Knapen³

et al. 2019

A&A

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Context. Spiral galaxies are very common in the local Universe, but their formation, evolution, and interplay with bars remain poorly understood after more than a century of astronomical research on the topic. Aims. We use a sample of 391 nearby galaxies from the S 4 G survey to characterise the winding angle and amplitude of spiral arms as a function of disc properties, such as bar strength, in all kinds of spirals (grand-design, multi-armed, and flocculent). Methods. We derived global pitch angles in 3.6 µm de-projected images from i) average measurements of individual logarithmic spiral segments, and ii) for a subsample of 32 galaxies, from 2-D Fourier analyses. The strength of spirals was quantified from the tangential-to-radial force ratio and from the normalised m = 2 Fourier density amplitudes. Results. In galaxies with more than one measured logarithmic segment, the spiral pitch angle varies on average by ∼ 10 • between segments, but by up to 15 − 20 • . The distribution of the global pitch angle versus Hubble type (T ) is very similar for barred and non-barred galaxies when 1 T 5. Most spiral galaxies (> 90%) are barred for T > 5. The pitch angle is not correlated with bar strength, and only weakly with spiral strength. The amplitude of spirals is correlated with bar strength (and less tightly, with bar length) for all types of spirals. The mean pitch angle is hardly correlated with the mass of the supermassive black hole (estimated from central stellar velocity dispersion), with central stellar mass concentration, or with shear, questioning previous results in the literature using smaller samples. Conclusions. We do not find observational evidence that spiral arms are driven by stellar bars or by invariant manifolds. Most likely, discs that are prone to the development of strong bars are also reactive to the formation of prominent spirals, explaining the observed coupling between bar and spiral amplitudes.

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Polymer Brushes

Cited by 11 publications

References 18 publications

Black Hole Mass Scaling Relations for Spiral Galaxies. II. M_BH–M_,tot and M_BH–M_,disk

Black Hole Mass Scaling Relations for Spiral Galaxies. II. M_BH–M_,tot and M_BH–M_,disk

Inclination- and dust-corrected galaxy parameters: bulge-to-disc ratios and size-luminosity relations

The shapes of spiral arms in the S⁴G survey and their connection with stellar bars

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Polymer Brushes

Cited by 11 publications

References 18 publications

Black Hole Mass Scaling Relations for Spiral Galaxies. II. MBH–M*,tot and MBH–M*,disk

Black Hole Mass Scaling Relations for Spiral Galaxies. II. MBH–M*,tot and MBH–M*,disk

Inclination- and dust-corrected galaxy parameters: bulge-to-disc ratios and size-luminosity relations

The shapes of spiral arms in the S4G survey and their connection with stellar bars

Contact Info

Product

Resources

About

Black Hole Mass Scaling Relations for Spiral Galaxies. II. M_BH–M_,tot and M_BH–M_,disk

Black Hole Mass Scaling Relations for Spiral Galaxies. II. M_BH–M_,tot and M_BH–M_,disk

The shapes of spiral arms in the S⁴G survey and their connection with stellar bars