TY - JOUR
T1 - Aperture corrections for disk galaxy properties derived from the CALIFA survey. Balmer emission lines in spiral galaxies
AU - Iglesias-Páramo, J.
AU - Vílchez, J. M.
AU - Galbany, L.
AU - Sánchez, S. F.
AU - Rosales-Ortega, F. F.
AU - Mast, D.
AU - García-Benito, R.
AU - Husemann, B.
AU - Aguerri, J. A. L.
AU - Alves, J.
AU - Bekeraité, S.
AU - Bland-Hawthorn, J.
AU - Catalán-Torrecilla, C.
AU - de Amorim, A. L.
AU - de Lorenzo-Cáceres, A.
AU - Ellis, S.
AU - Falcón-Barroso, J.
AU - Flores, H.
AU - Florido, E.
AU - Gallazzi, A.
AU - Gomes, J. M.
AU - González Delgado, R. M.
AU - Haines, T.
AU - Hernández-Fernández, J. D.
AU - Kehrig, C.
AU - López-Sánchez, A. R.
AU - Lyubenova, M.
AU - Marino, R. A.
AU - Mollá, M.
AU - Monreal-Ibero, A.
AU - Mourão, A.
AU - Papaderos, P.
AU - Rodrigues, M.
AU - Sánchez-Blázquez, P.
AU - Spekkens, K.
AU - Stanishev, V.
AU - van de Ven, G.
AU - Walcher, C. J.
AU - Wisotzki, L.
AU - Zibetti, S.
AU - Ziegler, B.
PY - 2013/5/1
Y1 - 2013/5/1
N2 - This work investigates the effect of the aperture size on derived galaxy
properties for which we have spatially-resolved optical spectra. We
focus on some indicators of star formation activity and dust attenuation
for spiral galaxies that have been widely used in previous work on
galaxy evolution. We investigated 104 spiral galaxies from the CALIFA
survey for which 2D spectroscopy with complete spatial coverage is
available. From the 3D cubes we derived growth curves of the most
conspicuous Balmer emission lines (Hα, Hβ) for circular
apertures of different radii centered at the galaxy's nucleus after
removing the underlying stellar continuum. We find that the Hα
flux (f(Hα)) growth curve follows a well-defined sequence with
aperture radius that shows a low dispersion around the median value.
From this analysis, we derived aperture corrections for galaxies in
different magnitude and redshift intervals. Once stellar absorption is
properly accounted for, the f(Hα)/f(Hβ) ratio growth curve
shows a smooth decline, pointing toward the absence of differential dust
attenuation as a function of radius. Aperture corrections as a function
of the radius are provided in the interval [0.3, 2.5]R50.
Finally, the Hα equivalent-width (EW(Hα)) growth curve
increases with the size of the aperture and shows a very high dispersion
for small apertures. This prevents us from using reliable aperture
corrections for this quantity. In addition, this result suggests that
separating star-forming and quiescent galaxies based on observed
EW(Hα) through small apertures will probably result in low
EW(Hα) star-forming galaxies begin classified as quiescent.
AB - This work investigates the effect of the aperture size on derived galaxy
properties for which we have spatially-resolved optical spectra. We
focus on some indicators of star formation activity and dust attenuation
for spiral galaxies that have been widely used in previous work on
galaxy evolution. We investigated 104 spiral galaxies from the CALIFA
survey for which 2D spectroscopy with complete spatial coverage is
available. From the 3D cubes we derived growth curves of the most
conspicuous Balmer emission lines (Hα, Hβ) for circular
apertures of different radii centered at the galaxy's nucleus after
removing the underlying stellar continuum. We find that the Hα
flux (f(Hα)) growth curve follows a well-defined sequence with
aperture radius that shows a low dispersion around the median value.
From this analysis, we derived aperture corrections for galaxies in
different magnitude and redshift intervals. Once stellar absorption is
properly accounted for, the f(Hα)/f(Hβ) ratio growth curve
shows a smooth decline, pointing toward the absence of differential dust
attenuation as a function of radius. Aperture corrections as a function
of the radius are provided in the interval [0.3, 2.5]R50.
Finally, the Hα equivalent-width (EW(Hα)) growth curve
increases with the size of the aperture and shows a very high dispersion
for small apertures. This prevents us from using reliable aperture
corrections for this quantity. In addition, this result suggests that
separating star-forming and quiescent galaxies based on observed
EW(Hα) through small apertures will probably result in low
EW(Hα) star-forming galaxies begin classified as quiescent.
KW - techniques: spectroscopic
KW - galaxies: evolution
KW - surveys
KW - galaxies: ISM
U2 - 10.1051/0004-6361/201321460
DO - 10.1051/0004-6361/201321460
M3 - Short communication
SN - 0004-6361
VL - 553
JO - Astronomy & Astrophysics
JF - Astronomy & Astrophysics
M1 - L7
ER -