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The new emission line galaxies are listed in Table 2 containing
the following information:
column 1: The object's IAU-type name with the prefix HS. We note
by asterisk objects observed at Calar Alto.
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.
).
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
posesses 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. But if their emission
lines are quite narrow, they probably should be classified as Sy2. SA
is a probable super-association at the rim of an edge-on nearby disk
galaxy. Six objects are difficult to classify. They are coded as
NON.
column 8: One or more alternative names, according to the
information from NED.
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
marked by a
``plus''. For the objects observed in Calar Alto 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
.
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
marked by a ``plus''.
Below we give notes on several individual objects:
HS1015+3717: In the spectrum of this object a cosmic ray hit is
exactly on the line [O III]4959Å. This was not
corrected in the figure shown in Appendix A.
HS1214+3801: This is seemingly a supergiant H II-region at
the very rim of the nearby edge-on disc galaxy (SA(s)cd) NGC 4244
(Vhel = 224 kms-1 and BT=10.88). At the accepted
distance of NGC 4244 (D=4.5 Mpc) M
of HS1214+3801 is about
-
.
The difference between the systemic radial velocity of the
host galaxy and H II-region is small (32 kms-1) and does
not contradict that HS1214+3801 belongs to NGC 4244. Unfortunately,
the velocity field of NGC 4244 near the
position of the H II-region is unkown. Both, the single-dish H
I-measurements as summarized in Huchtmeier & Richter
([1989]), and an estimate of the maximum rotational velocity
V
130 kms-1 (which we obtained through the
Tully-Fisher relation from the absolute B-band magnitude of NGC 4244
of
-
), yield a range of expected velocity differences
between the galaxien material and HS 1214+3801 of up to +160 or
-100 kms-1. But since the 2-D spectrum of HS 1214+3801 with a
total spatial extent of about 20
(
0.5
kpc) shows evidences of internal motions with the amplitude of about
50 kms-1 we need to consider an alternative interpretation for
this object as a companion BCG. Its SF burst may be triggered due to
the tidal effect from the more massive galaxy, similar to the case of
HS 1717+4955 described in Kniazev et al. ([2000]). To
check this option one needs a detailed map of the NGC 4244 velocity field
including HS 1214+3801.
HS1214+3922: This BCG was reobserved with higher S/N ratio
in order to measure the flux of the [O III]4363 line,
necessary to determine unambiguously the electron temperature
Te([O III]) of the H II-region and the oxygen abundance.
A preliminary determination according to the procedure described by
Izotov et al. ([1997]) shows that it has
the low oxygen-abundances of log(O/H) + 12 = 7.76.