A Zone of Avoidance catalogue of 2MASS bright galaxies. I. Sample description and analysis. (arXiv:1811.02773v1 [astro-ph.GA])

A Zone of Avoidance catalogue of 2MASS bright galaxies. I. Sample description and analysis. (arXiv:1811.02773v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Schroder_A/0/1/0/all/0/1">Anja C. Schr&#xf6;der</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Driel_W/0/1/0/all/0/1">Wim van Driel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kraan_Korteweg_R/0/1/0/all/0/1">Renee C. Kraan-Korteweg</a>

We present a homogeneous 2MASS bright galaxy catalogue at low Galactic
latitudes ($|b| le 10.0^{rm o}$, called Zone of Avoidance) which is complete
to a Galactic extinction-corrected magnitude of $K^o_s le 11.25^{rm m}$. It
also includes galaxies in regions of high foreground extinctions ($E(B-V) >
0.95^{rm m}$) situated at higher latitudes. This catalogue forms the basis of
studies of large-scale structures, flow fields and extinction across the ZoA
and complements the ongoing 2MASS Redshift and Tully-Fisher surveys. It
comprises 3763 galaxies, 70% of which have at least one radial velocity
measurement in the literature. The catalogue is complete up to star density
levels of $log N_*/{rm deg}^2 <4.5$ and at least for $A_K < 0.6^{rm m}$ and likely as high as $A_K = 20^{rm m}$. Thus the ZoA in terms of bright NIR galaxies covers only $2.5-4$% of the whole sky. We use a diameter-dependent extinction correction to compare our sample with an unobscured, high-latitude sample. While the correction to the $K_s$ -band magnitude is sufficient, the corrected diameters are too small by about $4''$ on average. The omission of applying such a diameter-dependent extinction correction may lead to a biased flow field even at intermediate extinction values as found in the 2MRS survey. A slight dependence of galaxy colour with stellar density indicates that unsubtracted foreground stars make galaxies appear bluer. Furthermore, far-infrared sources in the DIRBE/IRAS extinction maps that were not removed at low latitudes affect the foreground extinction corrections of three galaxies and may weakly affect a further estimated $approx 20$% of our galaxies.

We present a homogeneous 2MASS bright galaxy catalogue at low Galactic
latitudes ($|b| le 10.0^{rm o}$, called Zone of Avoidance) which is complete
to a Galactic extinction-corrected magnitude of $K^o_s le 11.25^{rm m}$. It
also includes galaxies in regions of high foreground extinctions ($E(B-V) >
0.95^{rm m}$) situated at higher latitudes. This catalogue forms the basis of
studies of large-scale structures, flow fields and extinction across the ZoA
and complements the ongoing 2MASS Redshift and Tully-Fisher surveys. It
comprises 3763 galaxies, 70% of which have at least one radial velocity
measurement in the literature. The catalogue is complete up to star density
levels of $log N_*/{rm deg}^2 <4.5$ and at least for $A_K < 0.6^{rm m}$ and
likely as high as $A_K = 20^{rm m}$. Thus the ZoA in terms of bright NIR
galaxies covers only $2.5-4$% of the whole sky. We use a diameter-dependent
extinction correction to compare our sample with an unobscured, high-latitude
sample. While the correction to the $K_s$ -band magnitude is sufficient, the
corrected diameters are too small by about $4”$ on average. The omission of
applying such a diameter-dependent extinction correction may lead to a biased
flow field even at intermediate extinction values as found in the 2MRS survey.
A slight dependence of galaxy colour with stellar density indicates that
unsubtracted foreground stars make galaxies appear bluer. Furthermore,
far-infrared sources in the DIRBE/IRAS extinction maps that were not removed at
low latitudes affect the foreground extinction corrections of three galaxies
and may weakly affect a further estimated $approx 20$% of our galaxies.

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