Документ взят из кэша поисковой машины. Адрес
оригинального документа
: http://www.sao.ru/precise/Laboratory/Publications/2000/HSSIV/node8.html
Дата изменения: Sat Nov 25 17:34:14 2000 Дата индексирования: Sat Sep 11 20:29:26 2010 Кодировка: Поисковые слова: п п п п п п п п п п п п п |
The emission line galaxies observed are listed in Table 3 containing
the following information:
column 1: The object's IAU-type name with the prefix HS.
column 2: Right ascension for equinox B1950.
column 3: Declination for equinox B1950.
The coordinates were measured on direct plates of the HQS
and are accurate to
2
(Hagen et al. [1995]).
column 4: Heliocentric velocity and its r.m.s. uncertainty in
km s-1.
column 5: Apparent B-magnitude obtained by calibration of the digitized
photoplates with photometric standard stars (Engels et al. [1994]),
having an r.m.s. accuracy of
for objects fainter than
m
=
(Popescu et al. [1996]).
Since the algorithm to calibrate the objective prism spectra is
optimized for point sources the brightnesses of extended galaxies are
underestimated. The resulting systematic uncertainties are expected to
be as large as 2 mag (Popescu et al. [1996]). For about 1/3
of our objects, B-magnitudes are unavailable at the moment. We present
for them blue magnitudes obtained from the APM database. They are
marked by a ``plus" before the value in the corresponding
column. According to our estimate they are systematically brighter by
than the B-magnitudes obtained by calibration of the
digitized photoplates (r.m.s.
).
For all objects marked as from Popescu et al. ([2000]) one may
find improved B-magnitudes in Vennik, Hopp & Popescu ([2000])
which we do not list here for the sake of homogeneity.
column 6: Absolute B-magnitude, calculated from the apparent
B-magnitude and the heliocentric velocity. No correction for galactic
extinction is made as all objects are located at high
galactic latitudes and because the corrections are significantly smaller
than the uncertainties of the magnitudes.
column 7: Preliminary spectral classification type according to
the spectral data presented in this article. BCG means that the galaxy
possesses a characteristic H II-region spectrum and that the
luminosity is low enough. SBN and DANS are galaxies of lower
excitation with a corresponding position in line ratio diagrams, as
discussed in Paper I. SBN are the brighter fraction of this type. We
here follow the notation of Salzer et al. ([1989]).
Seyfert galaxies are separated mainly on diagnostic diagrams as AGN.
The criterion of broad lines was also used for the Sy classification.
With SA two probable super-association in a spiral
and an irregular galaxy are denoted. Two ELGs are difficult to classify.
They are coded as NON.
column 8: One or more alternative names, according to the
information from NED.
References to other sources of spectral information indicating that a
galaxy is an ELG are given in bold face.
The spectra of all emission-line galaxies are shown in Appendix A, which is available only in the electronic version of the journal.
The results of line flux measurements are given in Table 4.
It contains the following information:
column 1: The object's IAU-type name with the prefix HS.
By asterisk we note the objects observed during
non-photometric conditions.
column 2: Observed flux (in
10-16ergs-1cm-2) of the H
line.
For few objects without H
emission line the fluxes are given
for H
and marked by a ``plus''.
For several objects observed during non-photometric
conditions this parameter is unreliable and marked by (:).
columns 3,4,5: The observed flux ratios [O II]/H,
[O III]/H
and H
/H
.
For few objects without H
flux ratios are given
for H
and marked by a ``plus''.
columns 6,7: The observed flux ratios
[N II]6583 Å/H
,
and
([S II]
6716 Å +
6731 Å)/H
.
columns 8,9,10: Equivalent widths of the lines
[O II]3727 Å, H
and
[O III]
5007 Å.
For few objects without detected H
emission line the equivalent
widths are given for H
and marked by a ``plus''.
Among the 97 ELGs observed as first-priority candidates, 66 are classified as BCGs or probable BCGs. Two very faint objects (HS 1134+3640 and HS 1308+3845) are probably super-associations in the dwarf spiral NGC 3755 and in the Im galaxy UGC 8261. Two ELGs are probable LINERs. One candidate is difficult to classify. The remaining 26 ELGs are objects of lower excitation: either starburst nuclei galaxies (SBN and probable SBN) or their lower mass analogs dwarf amorphous nuclear starburst galaxies (DANS or probable DANS).
Below we give notes on several individual objects:
HS 0847+3639: The HS magnitude for this galaxy seems to be too
faint. The KUG magnitude (Takase & Miyauchi-Isobe [1993])
B=154 corresponds to MB=-196 and an SBN
classification as given in Table 3.
HS 0934+3629: The FWHMs, corrected for instrumental resolution,
for H
and H
are
1800 km s-1 and
1400 km s-1, respectively.
HS 1047+3714: Very strong N II line 6583 Å, H
is only seen in absorption.
HS 1116+3951: Uncertain H/H
ratio because of a cosmic
hit on H
.
HS 1134+3639: Probable low-mass companion of the galaxy NGC 3755 (the
distance is 230 or
25 kpc).
HS 1134+3640: Possible giant H II-region at the very edge of
the SAB(rs)c pec galaxy NGC 3755 with Vhel=1570 km s-1, seen
at an inclination angle of 60
.
The HI-line width at the level of 0.2 of the peak flux value W0.2=290
km s-1 (Huchtmeier & Richter [1989]) corresponds
to a maximum Vrot of
150 km s-1.
In accordance with the difference in radial velocities (-108 km s-1)
of HS 1134+3640 and the dynamical center of NGC 3755,
HS 1134+3640 is either
an H II-region in NGC 3755, or a companion like HS 1134+3639.
The real
situation can be checked only if it is determined whether this edge of
NGC 3755,
corresponds to the receding or approaching spiral arm.
HS 1308+3545: Giant H II-region at the edge of the B=160 Im
galaxy
UGC 8261 with Vhel=852 km s-1. Its HI-line width
W0.2=127 km s-1 corresponds to
a maximum Vrot of 65 km s-1. This is consistent
with the measured difference in the radial velocities of HS 1308+3545 and
the dynamical center of the Im galaxy.
HS 1620+4003: The profiles of the O III-lines
4959,5007 Å have a composite structure with a narrow (FWHM5007 = FWHM
)
and
broad (FWHM =
1800 km s-1) component. The broad to narrow
component flux ratio is 1.44.