Box/peanut and bar structures in edge-on and face-on nearby galaxies in the Sloan Digital Sky Survey – I. Catalogue

We derive the circular velocity curves of the gaseous and stellar discs of UGC 4056, a giant barred galaxy with an active galactic nucleus (AGN). We analyse UGC 4056 using the 2D spectroscopy obtained within the framework of the Mapping Nearby Galaxies at APO (MaNGA) survey. Using images and the colour index g − r from the Sloan Digital Sky Survey (SDSS), we determined the tilt of the galaxy, which allows us to conclude that the galaxy rotates clockwise with trailing spiral arms. We found that the gas motion at the central part of the UGC 4056 shows peculiar features. The rotation velocity of the gaseous disc shows a bump within around three kiloparsecs while the rotation velocity of the stellar disc falls smoothly to zero with decreasing galactocentric distance. We demonstrate that the peculiar radial velocities in the central part of the galaxy may be caused by the inflow of the gas towards the nucleus of the galaxy. The unusual motion of the gas takes place at the region with the AGN-like radiation and can be explained by the gas response to the bar potential.

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Detecting galaxy–filament alignments in the Sloan Digital Sky Survey III

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz539 ◽

2019 ◽

Vol 485 (2) ◽

pp. 2492-2504 ◽

Cited By ~ 11

Author(s):

Yen-Chi Chen ◽

Shirley Ho ◽

Jonathan Blazek ◽

Siyu He ◽

Rachel Mandelbaum ◽

...

Keyword(s):

Narrow Range ◽

Stellar Mass ◽

Sloan Digital Sky Survey ◽

Nearby Galaxy ◽

Matter Distribution ◽

Direction Parallel ◽

Significant Alignment ◽

Sky Survey ◽

Nearby Galaxies ◽

Web Reconstruction

Abstract Previous studies have shown the filamentary structures in the cosmic web influence the alignments of nearby galaxies. We study this effect in the LOWZ sample of the Sloan Digital Sky Survey using the ‘Cosmic Web Reconstruction' filament catalogue. We find that LOWZ galaxies exhibit a small but statistically significant alignment in the direction parallel to the orientation of nearby filaments. This effect is detectable even in the absence of nearby galaxy clusters, which suggests it is an effect from the matter distribution in the filament. A non-parametric regression model suggests that the alignment effect with filaments extends over separations of 30–40 Mpc. We find that galaxies that are bright and early-forming align more strongly with the directions of nearby filaments than those that are faint and late-forming; however, trends with stellar mass are less statistically significant, within the narrow range of stellar mass of this sample.

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Calculation of velocity dispersion of the nearby galaxies using different stellar template libraries

Serbian Astronomical Journal ◽

10.2298/saj1080057l ◽

2010 ◽

pp. 57-69

Author(s):

Ana Lalovic

Keyword(s):

Reasonable Agreement ◽

Velocity Dispersion ◽

Signal To Noise Ratio ◽

Sloan Digital Sky Survey ◽

Signal To Noise ◽

Method Of Calculation ◽

Sky Survey ◽

Best Fitting ◽

Nearby Galaxies ◽

Spectral Libraries

We present the central velocity dispersion measurements of the nearby galaxies from the Sloan Digital Sky Survey (SDSS). Using the sample from the paper by Ho et al. 2009, we have selected 23 galaxies for which we calculate the velocity dispersion. We have used the Penalized Pixel-Fitting code (Cappellari and Emsellem2004) to measure the velocity dispersion throughout the four chosen spectral regions: (3800,4568)?A, (4568,5336)?A, (5336,6104) and (6104,6872)?A. In all these regions, we have separately calculated dispersions and corresponding errors. We found that the measured values may vary with the change of spectral region, but, if weighted properly with the measure of the goodness of the fit, the final results will be shifted coloser to those for the best fitting regions. We have also tested how the use of different spectral libraries (Miles, Valdes and Elodie databases) influences measurements and we showed that they do not affect measurements much. However, Elodie stellar library introduces the smallest errors in the velocity dispersion and it is the most stable throughout all four spectral regions. For these reasons it should be used preferentially when dealing with the SDSS spectra. We compare the results with the above mentioned paper and find a reasonable agreement. The agreement with the dispersions available in the HyperLeda database is very poor. The best agreement is obtained with SDSS measurements. We believe that our measurements are useful since SDSS velocity dispersions measurements are not available for many galaxies and the method of calculation of the velocity dispersion outlined in this work enables calculation of velocity dispersion for any galaxy. Of course, spectra with signal-to-noise ratio below 20 should be taken with caution.

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The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory

The Astrophysical Journal Supplement Series ◽

10.3847/1538-4365/aa8992 ◽

2017 ◽

Vol 233 (2) ◽

pp. 25 ◽

Cited By ~ 217

Author(s):

Franco D. Albareti ◽

Carlos Allende Prieto ◽

Andres Almeida ◽

Friedrich Anders ◽

Scott Anderson ◽

...

Keyword(s):

Spectroscopic Data ◽

Sloan Digital Sky Survey ◽

Sky Survey ◽

Data Release ◽

Nearby Galaxies

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Oxygen abundance in nearby galaxies based on the spectra of H II regions from the Sloan Digital Sky Survey II: The interacting galaxies NGC 4631 and NGC 4656

Kinematics and Physics of Celestial Bodies ◽

10.3103/s0884591308040028 ◽

2008 ◽

Vol 24 (4) ◽

pp. 192-200 ◽

Cited By ~ 2

Author(s):

L. S. Pilyugin ◽

I. Yu. Izotova ◽

Yu. S. Sholudchenko

Keyword(s):

Sloan Digital Sky Survey ◽

Interacting Galaxies ◽

H Ii Regions ◽

Oxygen Abundance ◽

Sky Survey ◽

Nearby Galaxies

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Validity of abundances derived from spaxel spectra of the MaNGA survey

Astronomy and Astrophysics ◽

10.1051/0004-6361/201732185 ◽

2018 ◽

Vol 613 ◽

pp. A1 ◽

Cited By ~ 8

Author(s):

L. S. Pilyugin ◽

E. K. Grebel ◽

I. A. Zinchenko ◽

Y. A. Nefedyev ◽

V. M. Shulga ◽

...

Keyword(s):

Three Dimensional ◽

Abundance Ratio ◽

Sloan Digital Sky Survey ◽

Strong Line ◽

Sky Survey ◽

Calibration Relation ◽

Balmer Lines ◽

Nearby Galaxies ◽

The Mean ◽

The One

We measured the emission lines in the spaxel spectra of Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) galaxies in order to determine the abundance distributions therein. It has been suggested that the strength of the low-ionization lines, R2, N2, and S2, may be increased (relative to Balmer lines) in (some) spaxel spectra of the MaNGA survey due to a contribution of the radiation of the diffuse ionized gas. Consequently, the abundances derived from the spaxel spectra through strong-line methods may suffer from large errors. We examined this expectation by comparing the behaviour of the line intensities and the abundances estimated through different calibrations for slit spectra of H II regions in nearby galaxies, for fibre spectra from the Sloan Digital Sky Survey, and for spaxel spectra of the MaNGA survey. We found that the S2 strength is increased significantly in the fibre and spaxel spectra. The mean enhancement changes with metallicity and can be as large as a factor of ~2. The mean distortion of R2 and N2 is less than a factor of ~1.3. This suggests that Kaufmann et al.’s (2003, MNRAS, 346, 1055) demarcation line between active galactic nuclei and H II regions in the Baldwin, Phillips, & Terlevich (BPT, 1981, PASP, 93, 5) diagram is a useful criterion to reject spectra with significantly distorted strengths of the N2 and R2 lines. We find that the three-dimensional R calibration, which uses the N2 and R2 lines, produces reliable abundances in the MaNGA galaxies. The one-dimensional N2 calibration produces either reliable or wrong abundances depending on whether excitation and N/O abundance ratio in the target region (spaxel) are close to or differ from those parameters in the calibrating points located close to the calibration relation. We then determined abundance distributions within the optical radii in the discs of 47 MaNGA galaxies. The optical radii of the galaxies were estimated from the surface brightness profiles constructed based on the MaNGA observations.

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Intrinsic Characteristics of Quasars Redshifts

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v4i3.2020 ◽

2014 ◽

Vol 4 (3) ◽

pp. 655-661

Author(s):

Waleed Elsanhoury

Keyword(s):

Absolute Magnitude ◽

Sloan Digital Sky Survey ◽

Strong Correlations ◽

Sky Survey

Using Sloan Digital Sky Survey SDSS catalog, some intrinsic characteristics of Quasars (10,000 points) are developed of these are the strong correlations between redshifts and other parameters, e.g. combined magnitude, luminosity, and absolute magnitude .Moreover ,the Karlsson peak of our sample is also computed.

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