A black hole has been found slowly devouring a companion star at the heart of a dense star cluster – providing the first clear sign that black holes inhabit the dense stellar cities known as globular clusters.
Strong evidence for colossal black holes weighing millions or billions of times the Sun's mass has been found at the centres of galaxies. And smaller black holes have been discovered in a range of environments, including within the spiral arms of the Milky Way.
But there has previously been no clear-cut evidence for black holes of any size within globular clusters, spherical groupings of millions of stars. That is of interest because there are competing theories about what would happen to such black holes.

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`Irony` actually does mean `metal like`...

I was interested in reading this. The article I saw made no estimate as to the mas of this black hole, but since globular clusters are mostly fairly mature collections of stars with no new gas & dust left, any IMBHs in them will spend most of their time quiet and invisible. If there were a freak alignment of a globular between us and the LMC, or maybe M31, we might be able to examine it closely for central long-lasting & bright lensing events, but aside from that... move along, nothing to see here.

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Forming opinions as we speak

Hum,
There is a bit more here

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Artist’s impression of stellar-mass black hole

Attached Images

blackhole.gif (759 Bytes, 16 views)

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`Irony` actually does mean `metal like`...

Obviously in its dormant state.

Well, actually, there is another way that black holes might produce visible effects in globular clusters. The central regions of GCs are dense enough that gravitational interactions between stars can be frequent enough (especially over billions of years) to modify the density of stars. For example, three-body interactions between a close binary and a single star can give the single star a jolt of kinetic energy -- causing it to fly into an orbit which takes it far from the center of the GC -- which comes from the orbit of the binary -- which shrinks and turns into a "harder" binary system. Over very long periods of time, such interactions can modify the overall density distribution in the GC by a significant amount.

So, some people study GCs very carefully to measure the distribution of stars as a function of distance from the center. In some cases, the distributions can provide indirect evidence for very massive objects at the centers of GCs -- perhaps black holes.

For more information on this subject, look up papers by David Merritt. He's just one of the many players in this field, but he happens to be a member of my department, so I hear a lot about it from him ....

Hum,
a stellar-mass black hole.

Source

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`Irony` actually does mean `metal like`...

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"All your bias are belong to us." Ara Pacis
"A witty saying proves nothing." Voltaire

This certainly does not sound like a IMBH.

If this is a stellar black hole is it from a 1a or a typeII supernova?

And if it is a STELLAR black hole, why would it be unusual to find one of these in a STELLAR globular custer of stars?

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

Not Ia if it has 10 solar masses-- Ia's are made from 1.4 solar masses. It sounds like core collapse, unless there have been mergers of black holes. The reference to IMBHs suggest that mergers is one possible idea, however.
Good question, I don't know-- the parts quoted didn't say what the competing ideas were on the "fates" of such black holes.

The arguments against BHs in GCs are because of the dynamics:-

Type Ia supernovae cannot create black holes. The progenitor white dwarf is completely destroyed in the process. It seems that stellar-mass black holes can only be created in core-collapse supernovae or in mergers of two neutron stars.

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Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.
-- Richard Feynman

Good point-- that rules out Ia completely.