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3271. Seyferts in galaxy pairs and groups
ID:
ivo://CDS.VizieR/J/A+A/335/912
Title:
Seyferts in galaxy pairs and groups
Short Name:
J/A+A/335/912
Date:
21 Oct 2021
Publisher:
CDS
Description:
The occurrence of Seyfert galaxies in 6 samples representative of different cosmological environments (i.e. isolated pairs, compact and loose groups) is analysed. To avoid biases linked to subjective sample selection criteria only canonical samples, taken from the literature, are considered. It is found that the average frequency of Seyferts in all samples, is near 2%. Most Seyferts lying in pairs and compact groups show disturbed morphological appearance, whilst in loose groups disturbed and ``isolated'' Seyferts have roughly the same proportion. Then, within each sample, structures which host a Seyfert are compared to structures which do not. No appreciable differences regarding dynamical properties are found.
3272. 5 Seyferts reduced CO(2-1) cubes
ID:
ivo://CDS.VizieR/J/A+A/643/A127
Title:
5 Seyferts reduced CO(2-1) cubes
Short Name:
J/A+A/643/A127
Date:
21 Oct 2021
Publisher:
CDS
Description:
Active galactic nucleus (AGN) driven outflows are believed to play an important role in regulating the growth of galaxies, mostly via negative feedback. However, their effects on their hosts are far from clear, especially for low- and moderate-luminosity Seyferts. To investigate this issue, we obtained cold molecular gas observations, traced by the CO(2-1) transition, using the NOEMA interferometer of five nearby (distances between 19 and 58Mpc) Seyfert galaxies. The resolution of ~0.3-0.8 (~30-100pc) and field of view of NOEMA allowed us to study the CO(2-1) morphology and kinematics in the nuclear regions (~100pc) and up to radial distances of ~900pc. We detected CO(2-1) emission in all five galaxies with disky or circumnuclear ring-like morphologies. We derived cold molecular gas masses on nuclear (~100pc) and circumnuclear (~650pc) scales in the range from 10^6^ to 10^7^M_{sun}_ and from 10^7^ to 10^8^M_{sun}_, respectively. In all of our galaxies, the bulk of this gas is rotating in the plane of the galaxy. However, noncircular motions are also present. In NGC 4253, NGC 4388, and NGC 7465, we can ascribe the streaming motions to the presence of a large-scale bar. In Mrk 1066 and NGC 4388, the noncircular motions in the nuclear regions are explained as outflowing material due to the interaction of the AGN wind with molecular gas in the galaxy disk. We conclude that for an unambiguous and precise interpretation of the kinematics of the cold molecular gas, we need detailed knowledge of the host galaxy (i.e., presence of bars, interactions, etc.), and also of the ionized gas kinematics and ionization cone geometry.
3273. SFI++ II. A new I-band Tully-Fisher catalog
ID:
ivo://CDS.VizieR/J/ApJS/172/599
Title:
SFI++ II. A new I-band Tully-Fisher catalog
Short Name:
J/ApJS/172/599
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the SFI++ data set, a homogeneously derived catalog of photometric and rotational properties and the Tully-Fisher distances and peculiar velocities derived from them. We make use of digital optical images, optical long-slit spectra, and global HI line profiles to extract parameters of relevance to disk scaling relations, incorporating several previously published data sets as well as a new photometric sample of some 2000 objects. According to the completeness of available redshift samples over the sky area, we exploit both a modified percolation algorithm and the Voronoi-Delaunay method to assign individual galaxies to groups as well as clusters, thereby reducing scatter introduced by local orbital motions. We also provide corrections to the peculiar velocities for both homogeneous and inhomogeneous Malmquist bias, making use of the 2MASS Redshift Survey density field to approximate large-scale structure. The final SFI++ peculiar velocity catalog contains 4861 field and cluster galaxies.
3274. SFR for starburst galaxies
ID:
ivo://CDS.VizieR/J/ApJ/701/1398
Title:
SFR for starburst galaxies
Short Name:
J/ApJ/701/1398
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a comparison of star formation rates (SFR) determined from mid-infrared 7.7um polycyclic aromatic hydrocarbon (PAH) luminosity [SFR(PAH)], from 1.4GHz radio luminosity [SFR(radio)], and from far-ultraviolet luminosity [SFR(UV)] for a sample of 287 starburst galaxies with z<0.5 having Spitzer IRS observations.
3275. SFR for WISE + SDSS spectroscopic galaxies
ID:
ivo://CDS.VizieR/J/ApJS/219/8
Title:
SFR for WISE + SDSS spectroscopic galaxies
Short Name:
J/ApJS/219/8
Date:
21 Oct 2021
Publisher:
CDS
Description:
We combine Sloan Digitital Sky Survey (SDSS) and WISE photometry for the full SDSS spectroscopic galaxy sample, creating spectral energy distributions (SEDs) that cover {lambda}=0.4-22{mu}m for an unprecedentedly large and comprehensive sample of 858365 present-epoch galaxies. Using MAGPHYS (da Cunha+ 2008MNRAS.388.1595D), we then simultaneously and consistently model both the attenuated stellar SED and the dust emission at 12 and 22{mu}m, producing robust new calibrations for monochromatic mid-IR star formation rate (SFR) proxies. These modeling results provide the first mid-IR-based view of the bimodality in star formation activity among galaxies, exhibiting the sequence of star-forming galaxies ("main sequence") with a slope of dlogSFR/dlogM_*_=0.80 and a scatter of 0.39dex. We find that these new SFRs along the SF main sequence are systematically lower by a factor of 1.4 than those derived from optical spectroscopy. We show that for most present-day galaxies, the 0.4-22{mu}m SED fits can exquisitely predict the fluxes measured by Herschel at much longer wavelengths. Our analysis also illustrates that the majority of stars in the present-day universe are formed in luminous galaxies (~L*) in and around the "green valley" of the color-luminosity plane. We make publicly available the matched photometry catalog and SED modeling results.
3276. SFR & gas-phase metallicity in MaNGA gal.
ID:
ivo://CDS.VizieR/J/ApJ/882/9
Title:
SFR & gas-phase metallicity in MaNGA gal.
Short Name:
J/ApJ/882/9
Date:
21 Oct 2021
Publisher:
CDS
Description:
The role of gas accretion in galaxy evolution is still a matter of debate. The presence of inflows of metal-poor gas that trigger star formation bursts of low metallicity has been proposed as an explanation for the local anticorrelation between star formation rate (SFR) and gas-phase metallicity (Z_g_) found in the literature. In the present study, we show how the anticorrelation is also present as part of a diversified range of behaviors for a sample of more than 700 nearby spiral galaxies from the SDSS-IV MaNGA survey. We have characterized the local relation between SFR and Z_g_ after subtracting the azimuthally averaged radial profiles of both quantities. Of the analyzed galaxies, 60% display an SFR-Z_g_ anticorrelation, with the remaining 40% showing no correlation (19%) or positive correlation (21%). Applying a random forest machine-learning algorithm, we find that the slope of the correlation is mainly determined by the average gas-phase metallicity of the galaxy. Galaxy mass, g-r colors, stellar age, and mass density seem to play a less significant role. This result is supported by the performed second-order polynomial regression analysis. Thus, the local SFR-Z_g_ slope varies with the average metallicity, with the more metal-poor galaxies presenting the lowest slopes (i.e., the strongest SFR-Z_g_ anticorrelations), and reversing the relation for more metal-rich systems. Our results suggest that external gas accretion fuels star formation in metal-poor galaxies, whereas in metal-rich systems, the gas comes from previous star formation episodes.
3277. SFR in galaxies at redshift z~0.8
ID:
ivo://CDS.VizieR/J/MNRAS/454/1332
Title:
SFR in galaxies at redshift z~0.8
Short Name:
J/MNRAS/454/1332
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the star formation history for a sample of 154 galaxies with stellar mass 10^10^<~M*<~10^12^M_{sun}_ in the redshift range 0.7<z<0.9. We do this using stellar population models combined with full-spectrum fitting of good quality spectra and high-resolution photometry. For a subset of 68 galaxies (M*>~10^11^M_{sun}_) we additionally construct dynamical models. These use an axisymmetric solution to the Jeans equations, which allows for velocity anisotropy, and adopts results from abundance matching techniques to account for the dark matter content. We find that (i) the trends in star formation history observed in the local Universe are already in place by z~1: the most massive galaxies are already passive, while lower mass ones have a more extended star formation histories, and the lowest mass galaxies are actively forming stars; (ii) we place an upper limit of a factor 1.5 to the size growth of the massive galaxy population; (iii) we present strong evidence for low dark matter fractions within 1Re (median of 9 per cent and 90th percentile of 21 per cent) for galaxies with M*>~10^11^M_{sun}_ at these redshifts; and (iv) we confirm that these galaxies have, on average, a Salpeter normalization of the stellar initial mass function.
3278. SFR-M_*_ relation from ZFOURGE
ID:
ivo://CDS.VizieR/J/ApJ/817/118
Title:
SFR-M_*_ relation from ZFOURGE
Short Name:
J/ApJ/817/118
Date:
21 Oct 2021
Publisher:
CDS
Description:
We explore star formation histories (SFHs) of galaxies based on the evolution of the star formation rate stellar mass relation (SFR-M_*_). Using data from the FourStar Galaxy Evolution Survey (ZFOURGE) in combination with far-IR imaging from the Spitzer and Herschel observatories we measure the SFR-M_*_ relation at 0.5<z<4. Similar to recent works we find that the average infrared spectral energy distributions of galaxies are roughly consistent with a single infrared template across a broad range of redshifts and stellar masses, with evidence for only weak deviations. We find that the SFR-M_*_ relation is not consistent with a single power law of the form SFR{propto}M_{star}_^{alpha}^ at any redshift; it has a power law slope of {alpha}~1 at low masses, and becomes shallower above a turnover mass (M_0_) that ranges from 10^9.5^ to 10^10.8^M_{sun}_, with evidence that M_0_ increases with redshift. We compare our measurements to results from state-of-the-art cosmological simulations, and find general agreement in the slope of the SFR-M_*_ relation albeit with systematic offsets. We use the evolving SFR-M_*_ sequence to generate SFHs, finding that typical SFRs of individual galaxies rise at early times and decline after reaching a peak. This peak occurs earlier for more massive galaxies. We integrate these SFHs to generate mass growth histories and compare to the implied mass growth from the evolution of the stellar mass function (SMF). We find that these two estimates are in broad qualitative agreement, but that there is room for improvement at a more detailed level. At early times the SFHs suggest mass growth rates that are as much as 10x higher than inferred from the SMF. However, at later times the SFHs under-predict the inferred evolution, as is expected in the case of additional growth due to mergers.
3279. SFR of distant galaxies
ID:
ivo://CDS.VizieR/J/A+A/430/115
Title:
SFR of distant galaxies
Short Name:
J/A+A/430/115
Date:
21 Oct 2021
Publisher:
CDS
Description:
Studies of distant galaxies have shown that ellipticals and large spirals (Schade et al., 1999ApJ...525...31S; Lilly et al., 1998ApJ...500...75L) were already in place 8Gyr ago, leading to a very modest recent star formation (Brinchmann & Ellis, 2000ApJ...536L..77B) in intermediate mass galaxies (3-30*10^10^M_{sun}_). This is challenged by a recent analysis (Heavens et al., 2004Natur.428..625H) of the fossil record of the stellar populations of ~105 nearby galaxies, which shows that intermediate mass galaxies formed or assembled the bulk of their stars 4 to 8Gyr ago. Here we present direct observational evidence supporting this findings from a long term, multi-wavelength study of 195 z>0.4 intermediate mass galaxies, mostly selected from the Canada France Redshift Survey (CFRS, Cat. <VII/225>).
3280. SFR of M31 from resolved stars in near-IR
ID:
ivo://CDS.VizieR/J/AJ/132/271
Title:
SFR of M31 from resolved stars in near-IR
Short Name:
J/AJ/132/271
Date:
21 Oct 2021
Publisher:
CDS
Description:
We discuss H and K observations of three fields in the bulge and disk of M31 obtained with the ALTAIR adaptive optics system and NIRI instrument on Gemini North. These are the highest resolution and deepest near-infrared observations obtained to date of the inner regions of M31 and demonstrate the promise of ground-based adaptive optics for studying the crowded regions of nearby galaxies. We have combined our observations with previously published Hubble Space Telescope Near-Infrared Camera and Multi-Object Spectrometer observations of nine M31 fields and have derived the coarse star formation histories of M31's bulge and inner disk. From fits to the MK luminosity functions, we find the stellar population mix to be dominated by old, nearly solar-metallicity stars. The old populations, which we define as having age >=6Gyr, indeed dominate the star formation histories at all radii independent of the relative contributions of bulge and disk stars. Although all of our fields contain some bulge contribution, our results suggest that there is no age difference between the bulge and disk to the limit of our precision.

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