1. X-shaped radio sources as the core-dominated triple blazars
Andrzej Marecki
Centre for Astronomy
N. Copernicus University, Toruń, Poland
X-shaped radio sources as the
parent population of
core-dominated triple blazars
RTS 2012 Conference
Manchester,

2. X-shaped sources

3. collision of backflows?
The cause of X-shape:
collision of backflows?
3C20
3C192

4. Repositioning of a standard double leading to an X-shaped source

5. X-shaped sources
3C223
3C403

6. Core-dominant triples (CDT) from the FIRST survey

7. Overall structure of J1625+2712 – a CDT with a steep-spectrum core

8. The „core” of J
resolved with
the EVN.
It appears that
the „core” of J
is in fact a
compact double
misaligned w.r.t.
the outer lobes.
It's a new arm of
an X-shaped source.

9. J – SDSS image
Photometry: u=19.02, g=17.41, r=16.76, i=16.52, z=16.39
The redshift is unknown.

10. Core-dominant triples (CDT) from the FIRST survey

11. Beaming effects in classical FRII source

13. X-shaped sources
3C223
3C403

14. Core-dominant triples with blazar cores
663 kpc
(z=0.347)
625 kpc
(z=0.715)

15. Conclusions
1. Our preferred interpretation of the nature X-shaped sources
is that they are just standard doubles that have undergone
repositioning of the axis. The “wings” are former lobes.
2. At least some core-dominant triples (CDTs) can either be:
a) X-shaped sources seen shortly after the repositioning:
CDTs with steep-spectrum central component,
or:
b) “grown-up” X-shaped sources where the “active” arm
of the cross is beamed towards the observer:
CDTs with flat spectrum central component.
3. X-shaped sources are the parent population of CDTs
of large overall sizes (~5 x 105 kpc) and whose central
components are identified with blazars.