English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We have used the Very Large Array (VLA) to search for radio emission from theglobular cluster G1 (Mayall-II) in M31. G1 has been reported by Gebhardt et al.to contain an intermediate-mass black hole (IMBH) with a mass of ~2 x 10^4solar masses. Radio emission was detected within an arcsecond of the clustercenter with an 8.4 GHz power of 2 x 10^{15} W/Hz. The radio/X-ray ratio of G1is a few hundred times higher than that expected for a high-mass X-ray binaryin the cluster center, but is consistent with the expected value for accretiononto an IMBH with the reported mass. A pulsar wind nebula is also a possiblecandidate for the radio and X-ray emission from G1; future high-sensitivityVLBI observations might distinguish between this possibility and an IMBH. Ifthe radio source is an IMBH, and similar accretion and outflow processes occurfor hypothesized ~ 1000-solar-mass black holes in Milky Way globular clusters,they are within reach of the current VLA and should be detectable easily by theExpanded VLA when it comes on line in 2010.

Radio Emission from the Intermediate-mass Black Hole in the Globular Cluster G1