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Old January 6th 17, 05:06 AM posted to sci.astro.research
Martin Brown
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Posts: 1,707
Default What is this galaxy?

On 01/01/2017 03:47, wrote:
There are also 12 notes, one of
which says, in part "Because of the dust, it is also impossible to
assess the presence of a nucleus".


Doesn't look like dust is blocking view to center, if it is, the
dust is extraordinarily smooth.


Looks can be deceptive! IRAS infrared imaging was used to better
determine its luminosity profile in a paper from 2009 (fig 4 p1995):

http://iopscience.iop.org/article/10...138/6/1990/pdf

Since VCC1030 aka NGC4435 has a detected unresolved point source at its
core in VLA 8GHz radio observations I think it is highly likely that the
SM black hole is still there but the stripping of dust and gas out of
the smaller galaxy by the previous collision has starved it of food.

It looks like it ran right through the center of the adjacent galaxy,
and lost it's black hole to the larger galaxy, with the stars
continuing on, blowing out into a spherical shell that has the
appearance of a circle.


It is dynamically very difficult for this to happen without a 3 body
collision of roughly similar mass objects. But there *is* observational
evidence for a weakly emitting radio point source at the core (ie a BH).

At least one group thinks that some of what we see in this Virgo field
is confused by local galactic cirrus in the line of sight.

http://mnrasl.oxfordjournals.org/con...1/L26.full.pdf

But sorting out what is really going on would be a challenge. I'll
have to read some of those papers. But it really looks like it's
a galaxy without a central massive BH............and that's unusual
if so. Wonder if one of the papers shows spectroscopy of the central
region, I'll have to check.


Having been and had a look at it on CDS Strasbourg I am actually more
interested in the bright linear source with no obvious optical
counterpart that appears on XMM-Newton EPIC at about 10 O'clock from the
emissions of NGC 4438 (or is it an aeretfact)?.

http://cdsportal.u-strasbg.fr/?target=NGC%20%204435

Unfortunately Chandra field of view doesn't include it.

http://chandra.harvard.edu/photo/200...438/index.html

BTW It isn't a good idea to concentrate on the weirdest most twisted
tree that you can find if you want to understand how trees work.

Arp went down that path in an attempt to debunk the Big Bang (and to be
fair found a lot of very curious interacting galaxies as a result)

https://ned.ipac.caltech.edu/level5/..._contents.html

It is ARP120 in that catalogue.

VLT Cosmic Gem's programme observed this pair in 2011 - rather pretty.

https://www.eso.org/public/news/eso1131/

--
Regards,
Martin Brown