J/A+A/373/24 Blue compact galaxies from SBS (Pustilnik+ 2001)
Environment status of blue compact galaxies and trigger of star formation.
Pustilnik S.A., Kniazev A.Y., Lipovetsky V.A., Ugryumov A.V.
<Astron. Astrophys. 373, 24 (2001)>
=2001A&A...373...24P 2001A&A...373...24P
ADC_Keywords: Galaxies, photometry ; Radial velocities ; Spectroscopy
Keywords: galaxies: dwarf - galaxies: interaction - galaxies: evolution -
galaxies: starburst
Abstract:
The work studies of the environment of low-mass galaxies with active
star formation (SF) and a possible trigger of SF bursts due to
gravitational interaction. Following the study by Taylor et al.
(1995ApJS...99..427T 1995ApJS...99..427T), we extend the search for possible disturbing
galaxies of various masses to a much larger sample of 86 BCGs from the
sky region of the Second Byurakan survey (SBS). The BCG magnitudes and
radial velocities are revised and up-dated. The sample under study is
separated by the criteria: EW([O III]5007)>45Å and Vh<6000km/s nd
should be representative of all low-mass galaxies which experience SF
bursts.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 79 86 Main parameters of the studied
Blue Compact Galaxy (BCG) sample
notes.dat 80 71 Individual notes to table2
table3.dat 81 86 Parameters of the strongest disturbers of
BCGs - probable star formation burst triggers
tablea1.dat 164 27 Parameters of Observed Galaxies
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See also:
J/ApJ/511/639 : Abundances in blue compact galaxies (Izotov+, 1999)
J/A+AS/139/1 : HI in Byurakan blue compact galaxies (Thuan+, 1999)
J/A+AS/137/419 : Dynamics of blue compact galaxies I. The data (Oestlin + 1999)
J/A+AS/147/169 : Accurate positions of 2978 SBS objects (Bicay+, 2000)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Sequential number
4- 11 A8 --- BCG BCG Name (IAU-type, based on 1950 position)
12 A1 --- m_BCG [ABEN] Multiplicity index on BCG
13 A1 --- n_BCG [*] Individual note in notes.dat file
15- 16 I2 h RAh Right ascension (1950.0)
18- 19 I2 min RAm Right ascension (1950.0)
21- 24 F4.1 s RAs Right ascension (1950.0)
26 A1 --- DE- Declination sign (1950.0)
27- 28 I2 deg DEd Declination (1950.0)
30- 31 I2 arcmin DEm Declination (1950.0)
33- 34 I2 arcsec DEs Declination (1950.0)
37- 40 I4 km/s HRV Heliocentric radial velocity (1)
42 I1 --- r_HRV [1/4] Reference for HRV (G1)
44- 47 F4.1 Mpc Dist Distance for Virgo infall correction (3)
48 A1 --- n_Dist [*+] Indivudal note on Dist (4)
50 A1 --- n_Bmag [*+n] Note on Bmag (5)
51- 55 F5.2 mag Bmag B magnitude
57- 62 F6.2 mag BMAG Absolute B magnitude (6)
64- 65 A2 --- Glob LS: Local Supercluster, GF: general field
67- 81 A15 --- Names Other names
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Note (1): For more than 60 BCGs the r.m.s. uncertainty is less than 30km/s
(mainly from HI data). For seven BCGs it can reach ∼100km/s, and for
the remaining galaxies it is ∼50-60km/s
Note (3): Distance, accounting for Virgo infall correction from Kraan-Korteweg
(1986, Cat. VII/98) with Vinfall=220km/s
Note (4): The symbols have the following meaning:
* No. 31, distance is accepted from Georgiev et al. (1997AstL...23..514G 1997AstL...23..514G)
+ No. 37, Mkn 178: the distance is accepted to be equal to that of
its neighbours on the sky with close radial velocities and having
photometrical determinations.
Note (5): Origin of the Bmag values:
+ : unpublished CCD data (Lipovetsky et al., 2001, in prep.;
Kniazev et al. 2001, in prep.).
* : For several galaxies, B-magnitudes are based on the APM database
values (Irwin 1998, http://www.ast.cam.ac.uk/~apmcat/ ).
They were recalculated to the standard CCD B-magnitudes using
the relation between and derived on more than 100 galaxies,
as described by Kniazev et al. (2001, in prep.).
Its rms uncertainty is found to be 0.45mag
n : For a couple of objects, photometrical B-magnitudes are taken from NED
Note (6): Absolute B-magnitude, calculated from the apparent magnitude
and the distance, with no correction for the Galaxy extinction, since
it is small for considered sky region.
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Byte-by-byte Description of file: notes.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- BCG BCG name (IAU-type, based on 1950 position)
9 A1 --- m_BCG [ABEN] Multiplicity index on BCG
11- 80 A70 --- Note Text of the note
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Sequential number
4- 11 A8 --- BCG BCG name (IAU-type, based on 1950 position)
12 A1 --- m_BCG [ABEN] Multiplicity index on BCG
14- 23 A10 --- Partner Partner's name (1)
26- 27 I2 h RAh ? Partner right ascension (1950.0) (2)
29- 30 I2 min RAm ? Partner right ascension (1950.0)
32- 35 F4.1 s RAs ? Partner right ascension (1950.0)
37 A1 --- DE- Partner declination sign (1950.0)
38- 39 I2 deg DEd ? Partner declination (1950.0)
41- 42 I2 arcmin DEm ? Partner declination (1950.0)
44- 45 I2 arcsec DEs ? Partner declination (1950.0)
47- 50 I4 km/s HRVbcg BCG heliocentric radial velocity
52- 55 I4 km/s HRVpar ? Partner heliocentric radial velocity
57 I1 --- r_HRVbcg [1/6]? Reference for velocities (G1)
59 A1 --- n_Bmag [+*] Note on Bmag (3)
60- 63 F4.1 mag Bmag ? Partner B magnitude (from NED)
65- 69 F5.1 mag BMAG ? Partner absolute total B magnitude
71- 74 F4.1 mag DBMAG ? Differential B magnitude (Partner minus BGC)
76- 78 I3 kpc Dproj ? Projected distance between the BCG and the
partner (disturbing) galaxy
80- 81 A2 --- Trig Suggested trigger classification (4)
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Note (1): The name (or one of the best known names, such as NGC one)
of the suggested disturbing galaxy.
Prefix "S" in the name means the object is from SBS.
Prefix "A" means a new object (anonymous), found as an associated
galaxy in the spectroscopy data from the 6m telescope.
In the case of a BCG supposed to be a merger, its name is repeated in
this column. If neither merger morphology nor disturbing galaxy is
identified, this field is left blank.
Note (2): Not given for a suggested merger, or if no disturbing galaxy
is identified.
Note (3): Magnitude determination:
Most are taken from NED.
* magnitude recalculated from the APM B-magnitudes through
calibration with the CCD-based B-magnitudes, as described by
Kniazev et al. (2001, in prep.),
+ magnitude derived from the same CCD-frames on which target BCGs
were measured.
Note (4): Suggested trigger classification:
p: parent galaxy, when the disturbing galaxy is significantly
brighter than the target BCG
b: binary system, in which the target BCG and its disturbing galaxy
are dynamically comparable
f: fainter companion, when the disturbing galaxy is significantly
less massive than the target BCG
m, m? : merger morphology with the various degrees of confidence
The latter classification was performed through the comparison of the
morphology of candidate BCGs on the CCD frames from Lipovetsky et al.
(2001, in prep.) and Kniazev et al. (2001, in prep.), or on the DSS-2
images, with the galaxies shown by Keel & Wu (1995AJ....110..129K 1995AJ....110..129K).
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Group [SB] Type of galaxy:
S: SBS BCGs and discovered real neighbours
B: Background galaxies
3- 4 I2 --- Seq Sequential number
6- 14 A9 --- [PKL2001] Galaxy designation (based on 1950.0 position)
15 A1 --- n_[PKL2001] [*] Individual note (1)
17- 18 I2 h RAh Right ascension (1950.0)
20- 21 I2 min RAm Right ascension (1950.0)
23- 26 F4.1 s RAs Right ascension (1950.0)
28 A1 --- DE- Declination sign (1950.0)
29- 30 I2 deg DEd Declination (1950.0)
32- 33 I2 arcmin DEm Declination (1950.0)
35- 36 I2 arcsec DEs Declination (1950.0)
38 A1 --- n_Bmag [*+:] Note on Bmag (2)
39- 42 F4.1 mag Bmag B magnitude
44- 48 I5 km/s HRV Heliocentric radial velocity
50- 52 I3 km/s e_HRV rms uncertainty on HRV
54- 58 F5.1 mag BMAG Absolute B magnitude (3)
60- 66 A7 --- Type Preliminary spectral classification type (4)
69- 82 A14 --- Names Other Names
84-164 A81 --- Lines Identified lines (5)
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Note (1): Individual notes:
0916+5417: companion of BCG SBS 0916+543, which is not in the
studied BCG sample
1120+5838: companion of BCG SBS 1120+586, which is not in our sample
1242+5458: companion of SBS 1242+549
1317+5219: companion of BCG SBS 1317+523A
1358+5529: BCG SBS 1358+554E itself
1413+4934: BCG SBS 1413+495 itself
1502+5307: companion of BCG SBS 1503+531
1503+5121: companion of BCG SBS 1504+514N
1620+5744: BCG SBS 1620+577 itself
Note (2): Apparent B-magnitude from APM database (Irwin, 1998,
http://www.ast.cam.ac.uk/~apmcat/ ) which was recalculated to standard
CCD B-magnitude using the calibration suggested by Kniazev et al.
(2001, in prep.). Its rms uncertainty is 0.45mag over the magnitude
range b=14-18.5mag.
Note (3): Absolute B-magnitude calculated from the apparent B magnitude
and the heliocentric velocities. No correction for galactic extinction
is made because all observed objects are located at high galactic
latitudes and because the corrections are significantly smaller than
the uncertainties of the magnitudes. Hubble constant H0=75km/s/Mpc
is accepted.
Note (4): Preliminary spectral classification type according to the
presented spectral data. BCG/H II means that the galaxy possesses a
characteristic H II-region spectrum and a low enough luminosity
(Mb≥-20). SBN are spiral galaxies of lower excitation with the
central star formation burst and the corresponding position in the
line ratio diagrams, as discussed, e.g., in Ugryumov et al. (1999,
Cat. J/A+AS/135/511).
Seyfert galaxies are separated mainly on the diagnostic diagrams as
AGN. The criterion of broad lines was also used for the Sy
classification. The ELG type means that an object has emission lines
but is difficult to be classified using the existing data. ABS means
a galaxy with the detected and identified absorption lines.
Note (5): The list of spectral lines, well detected in the object
spectrum and used for classification and/or redshift measurement.
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Global notes
Note (G1): Reference to the source of velocity accepted:
1: Thuan et al. (1999, Cat. J/A+AS/139/1)
2: NED
3: Pustilnik et al. (1995ApJ...443..499P 1995ApJ...443..499P)
4: new measurements with the SAO 6m telescope (tablea1.dat)
5: UZC, Falco et al. (1999, Cat. J/PASP/111/438)
6: Carrasco et al. (1998AJ....115.1717C 1998AJ....115.1717C)
Some of our BCG velocities in NED, taken from HI-measurements by Thuan
et al. (1999, Cat. J/A+AS/139/1), are not reliable, since they
ignore the information on real or possible confusion. We used instead
for these galaxies the velocities from Pustilnik et al.
(1995ApJ...443..499P 1995ApJ...443..499P).
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History:
From electronic version of the journal
(End) Patrici Bauer [CDS] 17-Jan-2002