J/A+AS/142/399 BR surface photometry of emission-line galaxies (Vennik+, 2000)
Surface photometry of emission-line galaxies in low density regions.
Vennik J., Hopp U., Popescu C.C.
<Astron. Astrophys. Suppl. Ser. 142, 399 (2000)>
=2000A&AS..142..399V 2000A&AS..142..399V
ADC_Keywords: Galaxies, photometry ; Photometry, surface
Keywords: galaxies: photometry - galaxies: fundamental parameters -
galaxies: structure - cosmology: large scale structure of Universe
Abstract:
Detailed B and R surface photometry is performed for 139 faint
emission-line galaxies (ELGs) and for 2 non-ELGs. They are a subsample
of the ELG sample selected by Popescu et al. (1996A&AS..116...43P 1996A&AS..116...43P,
1998A&AS..133...13P 1998A&AS..133...13P) towards four nearby voids. We derived the
isophotal and integral photometric parameters and radial surface
brightness (SB) profiles. Our sample consists mostly of low luminosity
(<MB>med=-17.7), small linear size (<d25>med=6.0kpc)
(H0=75km/s/Mpc) and blue (<B-R>med=0.93) galaxies. About 83% of
the studied ELGs belong to the class of Blue Compact Galaxies (BCGs);
others are luminous Starburst Nucleus Galaxies (SBNs) and a few
interacting pairs. 72% of the ELGs possess a single dominant H II
region, while the remaining 28% show multiple knots. Furthermore 71%
of the ELGs show regular outer isophotes, and the remaining 29% reveal
disturbed outer morphologies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 97 125 Observed model-free photometric data in B and
colour characteristics
table5.dat 68 16 Observed model-free photometric data in R
table6.dat 101 125 Reduced photometric data and exponential model
parameters in B and morphological classes
table7.dat 91 16 Reduced photometric data and exponential model
parameters in R and morphological classes
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See also:
VII/39 : Bibliography of Surface Photometry of galaxies (Davoust+ 1982)
VII/115 : ESO-Uppsala galaxies Surface Photometry Cat. (Lauberts+ 1989)
J/A+AS/117/261 : BR surface photometry of galaxies (Vennik+, 1996)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- HS HS designation (Hamburg Schmidt Survey)
13 A1 --- n_HS [*] *: Isolated galaxies
15- 17 F3.1 arcsec re Effective equivalent radius
19- 22 F4.1 arcsec r25 ? Equivalent radii
of the 25Bmag/arcsec2 isophote
24- 27 F4.1 arcsec r26.5 Equivalent radii
of the 26.5Bmag/arcsec2 isophote
29- 32 F4.1 mag/arcsec+2 SuBro Observed central surface brightness in B
33 A1 --- u_SuBro Uncertainty flag on SuBr0
35- 39 F5.2 mag/arcsec+2 SuBre Effective surface brightness in B,
measured at reff
40 A1 --- u_SuBre Uncertainty flag on SuBre
42- 46 F5.2 mag B25 ? Total B-magnitude,
within the 25Bmag/arcsec2 isophote
47 A1 --- u_B25 Uncertainty flag on B25
49- 53 F5.2 mag BT Asymptotic B-magnitude
54 A1 --- u_BT Uncertainty flag on BT
56- 60 F5.2 mag RT ? Asymptotic R-magnitude
61 A1 --- u_RT Uncertainty flag on RT
63- 67 F5.2 mag (B-R)e ? B-R colour index, measured at reff
68 A1 --- u_(B-R)e Uncertainty flag on CIe
70- 73 F4.2 mag (B-R)25 ? B-R colour index, measured at the
25Bmag/arcsec2 isophote
74 A1 --- u_(B-R)25 Uncertainty flag on CI25
76- 77 A2 --- Grad [± :] Colour gradient classification (1)
79- 82 F4.2 --- b/a ? Mean minor-to-major axis ratio
84- 86 I3 deg PA ? Position angle,
measured counterclockwise from North
87 A1 --- u_PA Uncertainty flag on PA
89- 92 F4.2 --- c(in) Light concentration index
cin= L(0.3r25)/L(r_25)
94- 97 F4.2 --- c(31) ? Light concentration index
c31 = r(3/4LT)/r(1/4LT)
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Note (1): Colour gradient classification use the following symbols:
+ = definitely positive, i.e. with blue center and
getting redder outwards
+: = probably positive
- = definitely negative
-: = probably negative
blank = no gradients
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- HS HS designation (Hamburg Schmidt Survey)
14- 16 F3.1 arcsec re Effective radius
18- 21 F4.1 arcsec r24 Equivalent radii
of the 24Rmag/arcsec2 isophote
23- 26 F4.1 arcsec r25.5 Equivalent radii
of the 25.5Rmag/arcsec2 isophote
28- 31 F4.1 mag/arcsec+2 SuBro Observed central surface brightness in R
33- 37 F5.2 mag/arcsec+2 SuBre Effective surface brightness in R,
measured at reff
39- 43 F5.2 mag R24 ? Total R-magnitude,
within the 24Bmag/arcsec2 isophote
45- 49 F5.2 mag RT Asymptotic R-magnitude
51- 54 F4.2 --- b/a ? Mean minor-to-major axis ratio
56- 58 I3 deg PA ? Position angle,
measured counterclockwise from North
60- 63 F4.2 --- c(in) Light concentration index
cin= L(0.3r24)/L(r_24)
65- 68 F4.2 --- c(31) Light concentration index
c31 = r(3/4LT)/r(1/4LT)
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- HS HS designation (Hamburg Schmidt Survey)
13 A1 --- n_HS [*] *: Isolated galaxies
15- 20 F6.1 Mpc Dist Distance
22- 27 F6.2 mag BMAG Absolute B magnitude
28 A1 --- u_BMAG Uncertainty flag on BMAG
30- 33 F4.1 kpc reL Effective equivalent radius
34 A1 --- u_reL Uncertainty flag on reL
36- 39 F4.1 kpc r25L ? Equivalent radii
of the 25Bmag/arcsec2 isophote
40 A1 --- u_r25L Uncertainty flag on r25L
42- 44 F3.1 kpc rHII ? Seeing corrected approximate linear
size of the star-forming regions,
measured in the B band
45 A1 --- u_rHII Uncertainty flag on rHII
47- 50 F4.1 arcsec 1/alpha ? Exponential model scale length (") (1)
51 A1 --- u_1/alpha Uncertainty flag on 1/alpha
53- 55 F3.1 kpc 1/alphaL ? Exponential model scale length (kpc)
56 A1 --- u_1/alphaL Uncertainty flag on 1/alpha2
58- 62 F5.2 mag/arcsec+2 SuBr0 ? Exponential model central surface
brightness (1)
63 A1 --- u_SuBr0 Uncertainty flag on SuBr0
65- 69 F5.2 mag/arcsec+2 SuBr0c ? Corrected exponential model central
surface brightness
70 A1 --- u_SuBr0c Uncertainty flag on SuBr0c
72- 80 A9 --- Profile Profile type (G1)
81- 91 A11 --- SMB89 Salzer et al. morphological class (G2)
93- 98 A6 --- LTh85 Loose & Thuan morphological class (G2)
100-101 I2 --- TMT97 Telles et al. morphological class (G2)
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Note (1): Residuals: 1/alpha = 0.15"; SuBr0 = 0.2 mag/arcsec2
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- HS HS designation (Hamburg Schmidt Survey)
14- 18 F5.1 Mpc Dist Distance
20- 25 F6.2 mag RMAG Absolute R magnitude
27- 29 F3.1 kpc reL Effective radius
31- 34 F4.1 kpc r24L ? Equivalent radii
of the 24Rmag/arcsec2 isophote
36- 38 F3.1 kpc rHII ? Seeing corrected approximate linear
size of the star-forming regions,
measured in the R band
39 A1 --- u_rHII Uncertainty flag on rHII
41- 43 F3.1 arcsec 1/alpha ? Exponential model scale length (")
44 A1 --- u_1/alpha Uncertainty flag on 1/alpha
46- 48 F3.1 kpc 1/alphaL ? Exponential model scale length (kpc)
49 A1 --- u_1/alphaL Uncertainty flag on 1/alpha2
51- 55 F5.2 mag/arcsec+2 SuBr0 ? Exponential model central surface
brightness
56 A1 --- u_SuBr0 Uncertainty flag on SuBr0
58- 62 F5.2 mag/arcsec+2 SuBr0c ? Corrected exponential model central
surface brightness
63 A1 --- u_SuBr0c Uncertainty flag on SuBr0c
65- 71 A7 --- Profile Profile type (G1)
73- 82 A10 --- SMB89 Salzer et al. morphological class (G2)
84- 88 A5 --- LTh85 Loose & Thuan morphological class (G2)
90- 91 I2 --- TMT97 Telles et al. morphological class (G2)
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Global Notes:
Note (G1): Assigned profile type as follows:
Type 1 = pure exponential disk (d)
Type 2 = composite profile with nucleus or bulge:
n/b and disk (d);
probably an outer halo (h).
Type 3 = central light depression (c)
or always convex curvature over linear radius (cnv).
Type 4 = quasi-stellar (non-resolved) profile (st).
Type 5 = definitely non-exponential profile with concave curvature
over linear radius (cnc).
Note (G2): Morphological classes.
Following the prescriptions of Salzer et al. (1989ApJS...70..479S 1989ApJS...70..479S),
hereafter SMB89, we classified our ELGs as:
* Seyfert galaxies (Sy) and Starburst Nucleus Galaxies (SBN) have,
on average, similar magnitudes (MB≤-20) and sizes (∼20 kpc).
They can be disentangled from each other by including spectral line
characteristics. The classification of a few Seyfert galaxies in our
sample was obtained from the literature. Other ELGs with corresponding
luminosities and sizes are classified as SBN (or as Giant Irregulars -
GI, in a few cases)
* Dwarf Amorphous Nuclear Starburst Galaxies (DANS) are smaller (∼10kpc)
and less luminous (MB~-18.5) symmetric disk galaxies with bright
(stellar) nuclear region, of amorphous appearance, and show no
features in their disk
* H II Hotspot galaxies (HIIH) have sizes and luminosities as DANS but
are irregular in shape, with strong emission regions everywhere in the
galaxy, more often found off-center
* Dwarf H II Hotspot galaxies (DHIIH) are as HIIH but smaller in size
(∼3.8kpc) and in absolute magnitude (MB~-16.5)
* Sargent-Searle (SS) objects are the smallest (≤2kpc) and the least
luminous (<MB≥-14) ELGs
* Interacting Pairs (IP) consist of two galaxies of comparable size,
which show evidence of recent interaction.
The classes of DANS, HIIH, DHIIH and SS make up the broad group of
Blue Compact Galaxies (BCGs), and most of them are also dwarfs, namely
Blue Compact Dwarf Galaxies (BCDs). We assigned the general type of
BCD to some less clear cases, where it was not possible to distinguish
between different morphological subtypes. A few candidates in our
sample were classified as Magellanic Irregulars (MI) and Giant
Irregulars (GI).
Loose & Thuan, 1985, hereafter LTh85, studied a sample of ∼50 BCDs on
deep CCD frames and proposed a classification scheme based on the
regularity of the isophotal shapes of both the high-surface-brightness
(HSB) star-forming regions and the low-surface-brightness (LSB) outer
region. Each BCD is described by two letters, one lower case letter
which describes the location and shape of the star-forming regions
and one upper case letter which describes the shape of the outer isophotes
n = for a single star-forming region located at the nucleus of the
galaxy with circular or elliptical isophotes
i = for several star-forming regions which are not at the center
and possess irregular isophotes)
E = for circular or elliptical outer isophotes
I = for irregular outer isophotes)
LTh85 distinguished four main types of BCDs:
* iE, the most common type in their sample;
* nE;
* iI, with subtypes of cometary (iI,C), and merger (iI,M) evidences;
* i0, for pure stellar images without underlying older stellar population.
Finally, ∼10 galaxies (out of ∼50) in LTh85 sample, which show some
spiral structure, were reclassified as starburst spiral galaxies. For
clearly non-dwarf ELGs with some spiral features we use notation S...
In their study of structural and morphological properties of H II
galaxies, Telles et al., 1997MNRAS.288...78T 1997MNRAS.288...78T, hereafter TMT97,
proposed a further morphological classification scheme, based on two
main criteria: on the multiplicity of H II regions and on the shape
of the outer isophotes. Both morphological classification schemes of
LTh85 and TMT97 relay on similar structural features, but they are
complementary to each other: the scheme of TMT97 specifies the
multiplicity of the H II regions; LTh85 classes describe the outer
isophotes in more detail. For comparison of different morphological
classification schemes we assigned the TMT97-classes to our sample of
ELGs too, by means of describing the morphology of each ELG with two
integers. The first integer shows the number of resolved H II regions:
1 = single dominant giant H II region;
2 = double H II region;
3 = multiple (≥ 3) H II region.
The second integer characterizes outer structure:
1 = disturbed morphologies and irregular outer isophotes, extensions,
fans or tails beyond the H II regions;
2 = symmetric and regular objects, regardless of the multiplicity of
the star-forming regions (i.e. their internal structure).
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History:
From A&A electronic version and prepared via OCR at CDS.
References:
Loose & Thuan, 1985, in: Star-Forming Dwarf Galaxies and Related Objects,
Kunth D., Thuan T.X. and Van T.T. (eds.). Paris: Editions Frontieres, p. 73
(End) James Marcout, Patricia Bauer [CDS] 26-May-2000