BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Double black holes in open clusters and a highlight to their hiera
 rchical mergers in nuclear clusters - Debatri Chattopadhyay\, Cardiff Univ
 ersity
DTSTART:20221014T120000Z
DTEND:20221014T130000Z
UID:TALK179090@talks.cam.ac.uk
CONTACT:Isobel Romero-Shaw
DESCRIPTION:In this talk\, I will present a work that investigates the rel
 ationship between the global properties of star clusters and their double 
 black hole (DBH) populations.\nFor this study\, the code NBODY6 is used to
  evolve a suite of star cluster models with an initial mass of ~O(1e4) Msu
 n and varying initial parameters. This work concluded that cluster metalli
 city plays the most significant role in determining the lifespan of a clus
 ter\, while the initial half-mass radius is dominant in setting the rate o
 f BH exchange interactions in the central cluster regions. It is also obse
 rved  that the mass of interacting BHs\, rather than how frequently their 
 interactions with other BHs occur\, is more crucial in the thermal expansi
 on and eventual evaporation of the cluster. We formulate a novel approach 
 to easily quantify the degree of BH-BH dynamical activity in each model. 1
 2 in-cluster and three out-of-cluster (after ejection from the cluster) DB
 H mergers of different types across the eleven models are presented.\nIt i
 s noted that cluster initial density plays the most crucial role in determ
 ining the number of DBH mergers\, with the potential hint of too-high stel
 lar density preventing in-cluster BH mergers.\nI will also give a highligh
 t of my ongoing research on the formation of intermediate mass black holes
  (~10e2-10e4 Msun) in nuclear clusters with initial masses of ~O(1e6-8)Msu
 n. This work utilizes a semi-analytical fast code. Different initial clust
 er conditions are explored - from their masses\, density\, metallicity to 
 how black holes are paired in the models. We find that cluster mass evolut
 ion and double black hole pairing prescriptions used form important determ
 inants in the mass of the final intermediate mass black holes. \n\nMy othe
 r interests include: \nneutron stars\, radio pulsars including black hole-
 pulsar binaries and millisecond pulsars\, neutron stars in isolated binari
 es and star clusters\, black hole triple systems\, stellar black hole spin
 s
LOCATION:Potter room/Zoom
END:VEVENT
END:VCALENDAR