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 Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We study the formation of intermediate-mass ratio inspirals (IMRIs) triggeredby the interactions between two stellar black holes (BHs) and anintermediate-mass BH (IMBH) inhabiting the centre of a dense star cluster. Weexploit $N$-body models varying the IMBH mass, the stellar BH mass spectrum,and the star cluster properties. These simulations are coupled with asemi-analytic procedure to characterise the evolution of the remnant IMBH. TheIMRIs formation probability attains values $\sim 5-50\%$, with larger valuescorresponding to larger IMBH masses. IMRIs map out the stellar BH massspectrum, thus they might be used to unravel BH populations in star clustersharboring an IMBH. After the IMRI phase, an IMBH initially nearlymaximal(almost non-rotating) tends to decrease(increase) its spin. If IMBHsgrow mostly via repeated IMRIs, we show that only IMBH seeds sufficientlymassive ($M_{\rm seed} > 300$ M$_\odot$) can grow up to $M_{\rm imbh} >10^3$M$_\odot$ in dense globular clusters. Assuming that these seeds form at aredshift $z\sim 2-6$, we find that around $1-5\%$ of them would reach masses$\sim 500-1500$ M$_\odot$ at redshift $z=0$ and would exhibit low-spins,$S_{\rm imbh} < 0.2$. Measuring the mass and spin of IMBHs involved in IMRIscould help unravelling their formation mechanisms. We show that LISA can detectIMBHs in Milky Way globular clusters with a signal-to-noise ratio SNR$=10-100$,or in the Large Magellanic Cloud with an SNR$=8-40$. We provide the IMRIsmerger rate for LIGO ($\Gamma_{\rm LIG} = 0.003-1.6$ yr$^{-1}$), LISA($\Gamma_{\rm LIS} = 0.02-60$ yr$^{-1}$), ET ($\Gamma_{\rm ET} = 1-600$yr$^{-1}$), and DECIGO ($\Gamma_{\rm DEC} = 6-3000$ yr$^{-1}$). Our simulationsshow that IMRIs' mass and spin encode crucial insights on the mechanisms thatregulate IMBH formation and that the synergy among different detectors wouldenable us to fully unveil them. (Abridged)

astronomy and astrophysics

Merging stellar and intermediate-mass black holes in dense clusters:  implications for LIGO, LISA and the next generation of gravitational wave  detectors