Extragalactic Planets Observed Using Microlensing

[jim mcnamara]

http://iopscience.iop.org/article/10.3847/2041-8213/aaa5fb/meta (abstract).

Using microlensing the authors observed (my bolding):

We show that a population of unbound planets between stars with masses ranging from Moon to Jupiter masses is needed to explain the frequent Fe Kα line energy shifts observed in the gravitationally lensed quasar RXJ 1131–1231 at a lens redshift of z = 0.295 or 3.8 billion lt-yr away.

Does someone know the reason why unbound planets are the only reasonable way to explain their data? This is not my field, but looks like a big stretch to me, a priori.

 

[Borg]

I saw the same article in Science Daily last week and felt the same way. The Detection of Extrasolar Planets section of the Wikipedia microlensing article might help a little.

 

[Simon Peach]

Seems like a very long bow to me.

 

[stefan r]

http://iopscience.iop.org/article/10.3847/2041-8213/aaa5fb/meta (abstract).

Using microlensing the authors observed (my bolding):Does someone know the reason why unbound planets are the only reasonable way to explain their data? This is not my field, but looks like a big stretch to me, a priori.

Here is a free link to the paper

planets bound to stars will alter
the magnification map little because they are located far inside of the Einstein ring of their parent
stars