J/A+A/581/A65 IFU observations of NGC 4191 (Coccato+, 2015)
Properties and formation mechanism of the stellar counter-rotating components
in NGC 4191.
Coccato L., Fabricius M., Morelli L., Corsini E.M., Pizzella A.,
Erwin P., Dalla Bonta E., Saglia R., Bender R., Williams M.
<Astron. Astrophys. 581, A65 (2015)>
=2015A&A...581A..65C 2015A&A...581A..65C
ADC_Keywords: Galaxies, optical ; Spectroscopy
Keywords: galaxies: abundances - galaxies: kinematics and dynamics -
galaxies: formation - galaxies: stellar content -
galaxies: individual: NGC 4191
Abstract:
We here distinguish two counter-rotating stellar components in NGC
4191 and characterize their physical properties such as kinematics,
size, morphology, age, metallicity.
We obtained integral field spectroscopic observations with VIRUS-W and
used a spectroscopic decomposition technique to separate the
contribution of two stellar components to the observed galaxy
spectrum. We also performed a photometric decomposition, modeling the
galaxy with a Sersic bulge and two exponential disks of different
scale length, with the aim of associating these structural components
with the kinematic components. We then measured the equivalent width
of the absorption line indices on the best-fit models that represent
the kinematic components and compared our measurements to the
predictions of stellar population models that also account for the
variable abundance ratio of α elements.
Description:
The observations of NGC 4191 were carried on 1-3 and 6-7 April 2013
using the VIRUS-W Integral Field Unit (IFU) Spectrograph at the 2.7m
Harlan J. Smith Telescope of the McDonald Observatory (Texas, US).
The observations were dithered to fill the entire field of view. We
took six exposures of 1800s in each of the three dither positions
and bracketed and interleaved them with 300s sky nods.
Objects:
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RA (2000) DE Designation(s)
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12 13 50.38 +07 12 03.0 NGC 4191 = UGC 7233
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 73 1 Information on fits datacube
mfNGC4191.fits 2880 24481 Fits data cube
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 22 F3.1 arcsec/pix Scale [1.6] Scale of the image
24- 25 I2 --- Nx [70] Number of pixels along X-axis
27- 28 I2 --- Ny [38] Number of pixels along Y-axis
30- 33 I4 --- Nz [3313] Number of slices
35- 39 I5 Kibyte size [68856] Size of FITS file
41- 54 A14 --- FileName Name of FITS file
56- 73 A18 --- Title Title of the FITS file
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Acknowledgements:
Lodovico Coccato, lcoccato(at)eso.org
(End) Patricia Vannier [CDS] 02-Sep-2015