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Bochkarev, G. R.; Izotov, A. S.; Кондратьев, С. А.

doi:10.1023/a:1015187511512

Cited by 7 publications

(7 citation statements)

References 1 publication

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“…due to intergalactic ionizing background radiation (e.g. Bochkarev & Sunyaev ) or ionizing radiation from the bright disc (e.g. Bland‐Hawthorn & Maloney ) in the case of warps.…”

Section: Discussionmentioning

confidence: 99%

The link between the baryonic mass distribution and the rotation curve shape

Swaters

Sancisi²,

Hulst

et al. 2012

Monthly Notices of the Royal Astronomical Society

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The observed rotation curves of disc galaxies, ranging from late‐type dwarf galaxies to early‐type spirals, can be fitted remarkably well simply by scaling up the contributions of the stellar and H i discs. This ‘baryonic scaling model’ can explain the full breadth of observed rotation curves with only two free parameters. For a small fraction of galaxies, in particular early‐type spiral galaxies, H i scaling appears to fail in the outer parts, possibly due to observational effects or ionization of H i. The overall success of the baryonic scaling model suggests that the well‐known global coupling between the baryonic mass of a galaxy and its rotation velocity (known as the baryonic Tully–Fisher relation) applies at a more local level as well, and it seems to imply a link between the baryonic mass distribution and the distribution of total mass (including dark matter).

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“…due to intergalactic ionizing background radiation (e.g. Bochkarev & Sunyaev ) or ionizing radiation from the bright disc (e.g. Bland‐Hawthorn & Maloney ) in the case of warps.…”

Section: Discussionmentioning

confidence: 99%

The link between the baryonic mass distribution and the rotation curve shape

Swaters

Sancisi²,

Hulst

et al. 2012

Monthly Notices of the Royal Astronomical Society

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“…van Gorkom 1993). If the metagalactic UV background is sufficiently strong, beyond a certain galactic radius the cold gas may become ionized (Bochkarev & Siuniaev 1977) The total Hα emission from star-forming galaxies is divided roughly in half, between discrete H ii regions and the DIG. Pioneering work by Reynolds (1984) established that only the massive OB stars are able to ionize the DIG.…”

Section: Notesmentioning

confidence: 99%

DEEP FABRY-PEROT Hα OBSERVATIONS OF NGC 7793: A VERY EXTENDED Hα DISK AND a TRULY DECLINING ROTATION CURVE

Dicaire

Carignan

Amram

et al. 2008

The Astronomical Journal

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Deep Hα observations of the Sculptor Group galaxy NGC 7793 were obtained on the ESO 3.60 m and the Marseille 36 cm telescopes at La Silla, Chile. Hα emission is detected all the way to the edge of the H i disk, making the H ii disk of NGC 7793 one of the largest ever observed in a quiet non-active galactic nucleus (AGN) late-type system. Even in the very outer parts, the H ii ionizing sources are probably mainly internal (massive stars in the disk) with an unlikely contribution from the extragalactic ionizing background. The Hα kinematics confirms what had already been seen with the H i observations: NGC 7793 has a truly declining rotation curve. However, the decline is not Keplerian and a dark halo is still needed to explain the rotation velocities in the outer parts.

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“…In carefully observed spiral galaxy discs the neutral column density falls off slowly with radius over most of the extents as seen with 21‐cm H i observations, but then a rapid truncation is seen. Bochkarev & Sunyaev (1977) first suggested that a truncation would occur in a spiral disc at a sufficient radius where the H i column becomes ionized by an extragalactic background. Disc edges have also been modelled by Maloney (1993), Dove & Shull (1994a) and Corbelli & Salpeter (1993).…”

Section: Introductionmentioning

confidence: 99%

Galaxies as fluctuations in the ionizing background radiation at low redshift

Linder

Gunesch

Davies

et al. 2003

Monthly Notices of the Royal Astronomical Society

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Some Lyman continuum photons are likely to escape from most galaxies, and these can play an important role in ionizing gas around and between galaxies, including gas that gives rise to Lyman‐alpha absorption. Thus the gas surrounding galaxies and in the intergalactic medium will be exposed to varying amounts of ionizing radiation depending upon the distances, orientations and luminosities of any nearby galaxies. The ionizing background can be recalculated at any point within a simulation by adding the flux from the galaxies to a uniform quasar contribution. Normal galaxies are found to almost always make some contribution to the ionizing background radiation at a redshift of zero, as seen by absorbers and at random points in space. Assuming that ∼2 per cent of ionizing photons escape from a galaxy such as the Milky Way, we find that normal galaxies make a contribution of at least 30–40 per cent of the assumed quasar background. Lyman‐alpha absorbers with a wide range of neutral column densities are found to be exposed to a wide range of ionization rates, although the distribution of photoionization rates for absorbers is found to be strongly peaked. On average, fewer highly ionized absorbers are found to arise further from luminous galaxies, while local fluctuations in the ionization rate are seen around galaxies having a wide range of properties.

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Untitled

Cited by 7 publications

References 1 publication

The link between the baryonic mass distribution and the rotation curve shape

The link between the baryonic mass distribution and the rotation curve shape

DEEP FABRY-PEROT Hα OBSERVATIONS OF NGC 7793: A VERY EXTENDED Hα DISK AND a TRULY DECLINING ROTATION CURVE

Galaxies as fluctuations in the ionizing background radiation at low redshift

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