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Date and Time of the Query: 2019-05-25 T21:11:16 PDT
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Notes for object NGC 4203

20 note(s) found in NED.


1. 2012ApJ...754...67F
Re:NGC 4203
NGC 4203 .LX.-*.-This galaxy represents a borderline case in the morphological
bulge classification. The bulge has a few dust lanes in HST F555W superimposed
on a generally smooth morphology. Fisher & Drory (2008) classify the bulge as
classical. The major axis velocity profile flattens out at about the bulge
radius of 14.7". The velocity dispersion profile shows a prominent rise from
about 105 km s^-1^ at the bulge radius to 175 km s^-1^ in the center. The h_3_
moments are mostly compatible with zero in the bulge region. The h_4_ moments
are noisy and show no significant trend within the covered region.

2. 2007MNRAS.377.1696M
Re:NGC 4203
NGC 4203. VLBA measurements by Anderson et al. (2004) of the unresolved (at the
mas scale) core provide the following fluxes: 9.9 mJy at 0.7 cm; 9.0 mJy at 1.35
cm; 10.2 mJy at 1.9 cm; 8.5 mJy at 3.6 cm; 8.1 mJy at 6 cm. Nagar et al. (2002)
have found that the radio core is variable.
In the UV monitoring by M05, the nuclear source showed large fluctuations,
1.5 between maximum and minimum in F250W (mean: 58 * 10^-17^ erg cm^-2^ s^-1^
A^-1^), and 1.4 in F330W (mean: 37 * 10^-17^ erg cm^-2^ s^-1^ A^-1^). The 2500-A
flux level in 2003 was 3-4 times higher than in the HST/WFPC2 2300-A measurement
by Barth et al. (1998; 21 * 10^-17^ erg cm^-2^ s^-1^ A^-1^) obtained in 1994.
The variable UV flux, which provides a lower limit on the AGN component, is thus
13 * 10^-17^ erg cm^-2^ s^-1^ A^-1^ at 3300 A, and (78 - 21) * 10^-17^ erg
cm^-2^ s^-1^ A^-1^ at 2500 A.
Ho et al. (2001) measured with Chandra a 2-10 keV flux of 44 * 10^-14^ erg
cm^-2^ s^-1^. Terashima et al. (2002) measured with ASCA a flux of 119 *
10^-14^ erg cm^-2^ s^-1^ at 0.5-2 keV, 205 * 10^-14^ erg cm^-2^ s^-1^ 2-10 keV
and a photon index {GAMMA} = 1.8. Terashima & Wilson (2003) verified that,
although the source was too bright to be measured with Chandra, the nuclear
source is unresolved and dominates the emission at the ASCA spatial resolution.
I will adopt at 0.5-2 keV the ASCA measurement, and at 2-10 keV the mean of the
ASCA and Chandra measurements, 125 * 10^-14^ erg cm^-2^ s^-1^, with a photon
index {GAMMA} = 1.8.
As noted above, the Tremaine et al. (2002) relation predicts, given the
velocity dispersion in this galaxy, 167 km s^-1^, a BH mass of 6.6 * 10^7^
M_sun_, but Sarzi et al. (2002) set an upper limit of 2.4 * 10^7^ M_sun_. In
this case I will therefore assume a mass of 1 * 10^7^ M_sun_.

3. 2006A&A...453...27C
Re:UGC 07256
UGC 7256: Ho & Peng (2001) measured 410 nuclear counts from a 2" diameter
circle. The ACIS count rate are converted to x-ray luminosity by assuming
{GAMMA} = 1.8 and N_H_ = 2 X 10^20^ cm^-2^.

4. 2005MNRAS.364..283E
Re:NGC 4203
NGC 4203. Type II outer-disc profile. The length L_bar_ of the bar, based on the
ellipticity minimum, is undoubtedly an overestimate; because this galaxy is
nearly face-on and lacks spiral arms, the ellipse-fit measurements a_min_ and
a_10_ are misleading or undefined.

5. 2005ApJ...627..674A
Re:NGC 4203
NGC 4203.This galaxy was also essentially unresolved by Ulvestad & Ho (2001b)
and A04 in their VLBA imaging. We classify the May VLA measurements as
tentative, as they have some similarity to the phase calibrator behavior.
However, the September observations show a significant decline with time, which
we believe is reliable.

6. 2005A&A...442..137N
Re:UGC 07256
UGC 7256 (NGC 4203) has a peculiar, filamentary gas distribution. The gas has a
general sense of motion around the center, but it is clearly not on regular
circular orbits. This galaxy bears some resemblance with UGC 4637 (see above).

7. 2005A&A...439..963T
Re:NGC 4203
J1215+331A:
also known as NGC4203, this source has a FIRST map available (slightly resolved;
6 mJy/beam). It very likely contains a central compact core (<1") with an
inverted spectrum, possibly due to free-free absorption (e.g. Falcke et al.
2000; Ho & Ulvestad 2001). It shows an inverted spectrum at high frequencies,
most likely too weak at low frequencies to confuse our observations, so ruled
out.

8. 2004A&A...418..877A
Re:NGC 4203
NGC 4203: a remarkably similar object to the z= 0.615 BL Lac object near
NGC 4151, is the strong X-ray source only 2.1 arcmin from NGC 4203. It
has a redshift of z= 0.614. This is another source which was not
included in the CP02 catalog due to previously known high redshift.
NGC 4203 is a liner type AGN with broad Balmer lines. It is also a
strong X-ray source and an IRAS infrared source. IXO45 is just W of the
BL Lac, Tonanzintla 1480, and optically identified with a blue quasar
candidate. Chandra snapshots of this field show the galaxy X-ray
emission and the strong emission of the adjacent ULXs (Terashima &
Wilson 2003).

9. 2003ApJ...583..145T
Re:NGC 4203
NGC 4203 (L1.9). A result on the same data set is presented in
Ho et al. (2001). The nucleus of this object has a large X-ray flux,
and pileup is severe in this observation. A bright source is seen 2'
southeast of the nucleus, which was also separated from the nucleus
with ASCA SIS observations (Iyomoto et al. 1998; Terashima et al.
2002). The Chandra observations show that there is no source confusing
the ASCA observation of the nucleus. Therefore, we used an ASCA flux
in the discussions.

10. 2002ApJS..139....1T
Re:NGC 4203
NGC 4203 (L1. 9).-An analysis of the ASCA data is presented in Iyomoto
et al. (1998). There exists a serendipitous source located 2' SE of the
nucleus of NGC 4203. In the present analysis, we extracted the SIS and
GIS spectra using a circular aperture with a radius of 1.2' and 1.5',
respectively. ROSAT PSPC and HRI images show a nucleus as well as some
extended emission (Halderson et al. 2001). The Chandra image published
by Ho et al. (2001) is dominated by the nucleus.

11. 2001ApJS..133...77H
Re:NGC 4203
NGC 4203 (L1.9). - The nucleus of this galaxy is classified as a
LINER 1.9 and is not formally part of our Seyfert sample. Most of the radio
flux is contained in a central, unresolved core, whose spectrum is inverted
({alpha}_6_^20^ = 0.44). Our 6 cm flux density of 11.2 mJy is in excellent
agreement with those from previous studies (Fabbiano, Gioia, & Trinchieri
1989, S_6_ = 11.6 mJy, {DELTA}{theta} ~ 1"; Wrobel & Heeschen 1991,
S_6_ = 12.5 mJy, {DELTA}{theta} = 5"), and our 20 cm measurement of
6.5 mJy matches well the value from the FIRST survey (S_20_ = 6.9 mJy).
The inverted spectrum, accompanied by an apparent lack of variability, may
indicate free-free absorption rather than synchrotron self-absorption.

12. 2000ApJ...542..186N
Re:NGC 4203
NGC 4203.-Wrobel (1991) derived a 6 cm flux density of 12.5 mJy at ~5"
resolution, and FIRST lists a peak 20 cm flux density of
6.9 mJy beam^-1^ (at a resolution of 5"), implying that the core has a
highly inverted spectrum between 20 and 6 cm, {alpha}_6_^20^ ~ 0.5. Our
D configuration 2 cm flux density of 12.3 mJy suggests a nonsimultaneous
spectral index {alpha}_2_^6^ ~ 0. The extended emission in the FIRST map
is in P.A. 90^deg^, more or less along the minor axis of the host
galaxy.

13. 1998ApJS..117..319A
Re:[ATZ98] D084
IRAS source; (weak) H{alpha} emission.

14. 1998ApJ...496..133B
Re:NGC 4203
NGC 4203.--Like NGC 3642, this galaxy hosts a compact nuclear UV source and
broad H{alpha} emission.

15. 1998AJ....116.2682C
Re:IRAS 12125+3328
NGC 4203. The ROSAT PSPC image is dominated by a point source that
probably indicates an AGN in NGC 4203 (Bregman, Hogg, & Roberts 1995).

16. 1997ApJS..112..391H
Re:NGC 4203
NGC 4203.--Broad H{alpha} is detected unambiguously in this LINER (Fig. 11g).
The fairly symmetric narrow lines of H, [N II], and [S II] can be fitted by a
single Gaussian with FWHM~350 km s^-1^.

17. 1994CAG1..B...0000S
Re:NGC 4203
S0_2_(1)
(P)
PH-7661-S
April 29/30, 1979
103aO
12 min
The two luminosity zones of a normal S0 are seen clearly in the
print here. The outer envelope is of very low surface brightness but
is seen well in this high-contrast print. The subtle structures in
this envelope (they are perhaps weak dust lanes) preclude a simple
S0_1_ classification. A stronger dust fragment, close to the border of
the inner bulge with the outer envelope (but burned out in this
print), is the reason for the S0_2_ classification.
The many condensations in the outer envelope are evidently
globular clusters. A dwarf elliptical companion exists east-southeast
of NGC 4203 at a separation of 7.4'. It is of type dE3,N and has a
bright nucleus about 1 mag brighter than the brightest condensation in
the envelope of NGC 4203 itself. The redshift distance of 21 Mpc,
based on v_o = 1072 km/s (H = 50), gives a projected linear separation
of 45 kpc.

18. 1994A&AS..105..481M
Re:NGC 4203
NGC 4203: There is a curious hump in the PA profile, of circa 15^deg^
in the range l = 30 to 50 arcsec. This is in line with the SAB0 type in
the RC2. There are also significant "gray" asymmetries (see Fig. 7).

19. 1973UGC...C...0000N
Re:UGC 07256
SAB0-: (de Vaucouleurs)

20. 1964RC1...C...0000d
Re:NGC 4203
Very bright, diffuse nucleus in a bright lens: 0.7 arcmin x 0.6 arcmin with
traces of a bar. Fairly bright envelope with weak traces of arcs or a ring.
Polarization:
Bull. Abastumani, No. 18, 15, 1955.


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