Inside-out star formation quenching and the need for a revision of bulge-disk decomposition concepts for spiral galaxies

AbstractThe distribution of chemical abundances and their variation in space and time are important tools to understand the chemical evolution of disks in spiral galaxies. In this work we present an one infall chemical evolution model for the Galactic disk based on an updated version of the Trieste group model. We adopted a pre enriched gas (to take into account the effect of the halo evolution), an inside-out scenario for the formation of the disk and a threshold in the surface gas density to regulate the star formation rate. The observational constraints for the solar neighbourhood were well reproduced and the spatial and time evolution of the radial abundance gradient were studied. We also used this model to reproduce the chemical evolution of some nearby spiral galaxies. The model was scaled to the disk properties of each galaxy and its dependence with the star formation efficiency and the time scale for the infalling gas into the disk were explored. Using this modified model we were able to reproduce the observed constraints available in the literature for this galaxies. The similarities and the differences between the chemical evolution of these objects and teh Milky Way are discussed to provide a basis to the understanding of the chemical evolution of disks.

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CHANG-ES

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731991 ◽

2018 ◽

Vol 611 ◽

pp. A72 ◽

Cited By ~ 26

Author(s):

Marita Krause ◽

Judith Irwin ◽

Theresa Wiegert ◽

Arpad Miskolczi ◽

Ancor Damas-Segovia ◽

...

Keyword(s):

Star Formation ◽

Wind Velocity ◽

Surface Density ◽

Spiral Galaxies ◽

Star Formation Rate ◽

Formation Rate ◽

Cosmic Ray ◽

Scale Height ◽

Radio Continuum ◽

Frequency Bands

Aim. The vertical halo scale height is a crucial parameter to understand the transport of cosmic-ray electrons (CRE) and their energy loss mechanisms in spiral galaxies. Until now, the radio scale height could only be determined for a few edge-on galaxies because of missing sensitivity at high resolution.Methods. We developed a sophisticated method for the scale height determination of edge-on galaxies. With this we determined the scale heights and radial scale lengths for a sample of 13 galaxies from the CHANG-ES radio continuum survey in two frequency bands.Results. The sample average values for the radio scale heights of the halo are 1.1 ± 0.3 kpc in C-band and 1.4 ± 0.7 kpc in L-band. From the frequency dependence analysis of the halo scale heights we found that the wind velocities (estimated using the adiabatic loss time) are above the escape velocity. We found that the halo scale heights increase linearly with the radio diameters. In order to exclude the diameter dependence, we defined a normalized scale height h˜ which is quite similar for all sample galaxies at both frequency bands and does not depend on the star formation rate or the magnetic field strength. However, h˜ shows a tight anticorrelation with the mass surface density.Conclusions. The sample galaxies with smaller scale lengths are more spherical in the radio emission, while those with larger scale lengths are flatter. The radio scale height depends mainly on the radio diameter of the galaxy. The sample galaxies are consistent with an escape-dominated radio halo with convective cosmic ray propagation, indicating that galactic winds are a widespread phenomenon in spiral galaxies. While a higher star formation rate or star formation surface density does not lead to a higher wind velocity, we found for the first time observational evidence of a gravitational deceleration of CRE outflow, e.g. a lowering of the wind velocity from the galactic disk.

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Clumpy Galaxies in the Early Universe

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306010210 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 376-380 ◽

Cited By ~ 3

Author(s):

Debra Meloy Elmegreen

Keyword(s):

Star Formation ◽

Early Universe ◽

Spiral Galaxies ◽

Star Forming ◽

Wide Range ◽

Thick Disks ◽

Hubble Ultra Deep Field

AbstractClumpy galaxies are prominent in the early Universe. We present morphological and photometric properties of a wide range of galaxy types and their star-forming clumps in the Hubble Ultra Deep Field. Sizes, scale lengths, and scale heights suggest that galaxies grow by a factor of 2 fromz= 4 to the present, and that thick disks are present in the early Universe. The largest clumps of star formation are 107–109M⊙in different galaxies, much more massive than large star-forming complexes in local galaxies. Dissolved clumps may account for both the exponential disks and the early thick disks of spirals and proto-spiral galaxies.

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Bar rejuvenation in S0 galaxies?

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1387 ◽

2020 ◽

Vol 495 (4) ◽

pp. 4548-4556

Author(s):

Sudhanshu Barway ◽

Kanak Saha

Keyword(s):

Star Formation ◽

Spiral Galaxies ◽

Theoretical Studies ◽

Tidal Interactions ◽

Colour Measurements ◽

Induce Star Formation ◽

Minor Mergers ◽

Stellar Masses ◽

S0 Galaxies ◽

Intermediate Density

ABSTRACT Based on the colour measurements from a multiband, multicomponent 2D decompositions of S0 and spiral galaxies using SDSS images, we found that bars are bluer in S0 galaxies compared to the spiral galaxies. Most of the S0s in our sample have stellar masses ∼L* galaxies. The environment might have played an important role as most of the S0s with bluer bars are in the intermediate-density environment. The possibility of minor mergers and tidal interactions that occurs frequently in the intermediate-density environment might have caused either a bar to form and/or induce star formation in the barred region of S0 galaxies. The underlying discs show the usual behaviour being redder in S0s compared to spiral galaxies while the bulges are red and old for both S0 and spiral galaxies. The finding of bluer bars in S0 galaxies is a puzzling issue and poses an interesting question at numerical and theoretical studies most of which shows that the bars are long-lived structures with old stellar populations.

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Star formation bursts in isolated spiral galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2006.10597.x ◽

2006 ◽

Vol 371 (2) ◽

pp. 530-536 ◽

Cited By ~ 18

Author(s):

C. Clarke ◽

D. Gittins

Keyword(s):

Star Formation ◽

Spiral Galaxies

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Environmental Effects on the ISM and Star Formation Properties of Nearby Spiral Galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316008188 ◽

2015 ◽

Vol 11 (S315) ◽

Author(s):

Angus Mok ◽

Christine Wilson

Keyword(s):

Star Formation ◽

Environmental Effects ◽

Spiral Galaxies ◽

Star Formation Rate ◽

Formation Rate ◽

Molecular Gas ◽

Turbulent Pressure ◽

Cluster Environment ◽

Gas Properties

AbstractWe studied molecular gas properties in a sample of 98 Hi - flux selected spiral galaxies within ~ 25 Mpc using the CO J = 3 − 2 line, observed with the JCMT, and subdivided into isolated, group, and Virgo subsamples. We find a larger mean H2 mass in the Virgo galaxies compared to group galaxies, despite their lower mean Hi mass. Combining our data with complementary Hα star formation rate measurements, Virgo galaxies have a longer molecular gas depletion times compared to group galaxies, perhaps due to heating processes in the cluster environment or differences in the turbulent pressure.

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Relation Between Star Formation and Angular Momentum in Spiral Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900032630 ◽

1983 ◽

Vol 100 ◽

pp. 135-136

Author(s):

L. Carrasco ◽

A. Serrano

Keyword(s):

Angular Momentum ◽

Star Formation ◽

Radial Distribution ◽

Spiral Galaxies ◽

Formation Rate ◽

Inverse Function ◽

Solar Neighborhood ◽

Spin Angular Momentum ◽

Stellar Formation ◽

The Galaxy

We derive the radial distribution of the specific angular momentum j=J/M, for the gas in M31, M51 and the galaxy, objects for which well observed unsmoothed rotation curves are available in the literature. We find the specific angular momentum to be anti-correlated with the present stellar formation rate, i.e. minima of spin angular momentum correspond to the loci of spiral arms. We find that the stellar formation rate is an inverse function of j. We derive new values of Oort's A constant for the arm and interarm regions in the solar neighborhood.

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Magnetic Fields and Star Formation for the ANS Sample of Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900190072 ◽

1990 ◽

Vol 140 ◽

pp. 233-234

Author(s):

J. Stryczynski

Keyword(s):

Magnetic Field ◽

Star Formation ◽

Magnetic Fields ◽

Field Strength ◽

Magnetic Field Strength ◽

Field Data ◽

Spiral Galaxies ◽

Magnetic Field Data ◽

Uv Range

From the literature we collected radio and magnetic field data for the ANS spiral galaxies. We suggest that the groups of objects, as revealed in the UV range, do not differ in magnetic field strength, although statistics of the sample are very poor.

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High reddening patches in Gaia DR2

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936881 ◽

2020 ◽

Vol 634 ◽

pp. A33

Author(s):

Leire Beitia-Antero ◽

Ana Inés Gómez de Castro ◽

Raúl de la Fuente Marcos

Keyword(s):

Star Formation ◽

Milky Way ◽

Spectroscopic Analysis ◽

Galactic Halo ◽

Spiral Galaxies ◽

Monte Carlo Sampling ◽

The Other ◽

Host Galaxies ◽

Galactic Model ◽

Gaia Dr2

Context. Deep GALEX UV data show that the extreme outskirts of some spiral galaxies are teeming with star formation. Such young stellar populations evolving so far away from the bulk of their host galaxies challenge our overall understanding of how star formation proceeds at galactic scales. It is at present unclear whether our own Milky Way may also exhibit ongoing and recent star formation beyond the conventional edge of the disk (∼15 kpc). Aims. Using Gaia DR2 data, we aim to determine if such a population is present in the Galactic halo, beyond the nominal radius of the Milky Way disk. Methods. We studied the kinematics of Gaia DR2 sources with parallax values between 1/60 and 1/30 milliarcseconds towards two regions that show abnormally high values of extinction and reddening; the results are compared with predictions from GALAXIA Galactic model. We also plotted the color–magnitude (CM) diagrams with heliocentric distances computed inverting the parallaxes, and studied the effects of the large parallax errors by Monte Carlo sampling. Results. The kinematics point towards a Galactic origin for one of the regions, while the provenance of the stars in the other is not clear. A spectroscopic analysis of some of the sources in the first region confirms that they are located in the halo. The CM diagram of the sources suggests that some of them are young.

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