text: 223,70,1450246388550414337,1437185924354478082,Barry McKernan,"New paper out! Starfall! <LINK> There are stellar mass black holes in AGN disks, sure, but there are also stars. Stars that orbit in the same sense as the gas in the disk can become massive O(100Msun) & undying! E.g. <LINK> Here we look at stars that move backwards through the AGN gas disk. They're ~ half the stars in the disk when it forms. These stars feel intense drag & fall inwards fast (&lt;0.1Myr) through the disk towards the central supermassive black hole (SMBH). <LINK> As the population of backwards stars grows at small disk radii, due to starfall, interactions can occur, binaries can form & scatterings can happen. Chaotic scatterings, particularly between binaries & singles, can send stars rocketing towards the central shred zone. <LINK> What happens next depends on the mass of the SMBH & whether a star is flung to one side or the other of the SMBH.... If the star is sent too close to the SMBH (&lt;=100million Msun), the tidal forces across it cause it to rupture, spilling its guts at high speed around the SMBH & into the inner disk, creating a tidal disruption event (TDE) If the star is sent around the SMBH against the flow of gas, e.g. <LINK> then the angular momentum of the unbound ejecta flung outwards cancels the angular momentum of the inner disk and causes much of the inner disk to slump onto the SMBH, clearing out a small cavity. <LINK> The result is an over-luminous TDE (tidal disruption event), followed by a low AGN state afterwards as the disk recovers on the viscous timescale. Cartoon Lightcurve is: <LINK> If the star goes the other way around the SMBH, the unbound ejecta adds angular momentum to the inner disk & pushes it outwards temporarily. The result is a more 'normal' TDE, followed by a higher AGN state as the ejecta + inner disk accrete on the viscous timescale. Lightcurve: <LINK> We expect roughly equal numbers of these 'prograde' and 'retrograde' TDEs in AGN. Particularly early on as starfall allows this population to build up & scatter in the inner disk. So, AGN TDEs are a nice probe of 'turning on' AGN. Now we need to find AGN flares that look like this! Stay tuned. With: @saavikford, @kantyellow, @AdamSJermyn, @doccosmos, Dan Stern, Nate Leigh, Taeho Ryu",https://arxiv.org/abs/2110.03741,"As active galactic nuclei (AGN) `turn on', some stars end up embedded in accretion disks around supermassive black holes (SMBHs) on retrograde orbits. Such stars experience strong headwinds, aerodynamic drag, ablation and orbital evolution on short timescales. Loss of orbital angular momentum in the first $\sim 0.1$~Myr of an AGN leads to a heavy rain of stars (`starfall') into the inner disk and onto the SMBH. A large AGN loss cone ($\theta_{\rm AGN,lc}$) can result from binary scatterings in the inner disk and yield tidal disruption events (TDEs). Signatures of starfall include optical/UV flares that rise in luminosity over time, particularly in the inner disk. If the SMBH mass is $M_{\rm SMBH} \ge 10^{8}M_{\odot}$, flares truncate abruptly and the star is swallowed. If $M_{\rm SMBH}<10^{8}M_{\odot}$, and if the infalling orbit lies within $\theta_{\rm AGN,lc}$, the flare is followed by a TDE which can be prograde or retrograde relative to the AGN inner disk. Retrograde AGN TDEs are over-luminous and short-lived as in-plane ejecta collide with the inner disk and a lower AGN state follows. Prograde AGN TDEs add angular momentum to inner disk gas and so start off looking like regular TDEs but are followed by an AGN high state. Searches for such flare signatures test models of AGN `turn on', SMBH mass, as well as disk properties and the embedded population. ",Starfall: A heavy rain of stars in 'turning on' AGN,13,"['New paper out! Starfall!\n<LINK>', 'There are stellar mass black holes in AGN disks, sure, but there are also stars. Stars that orbit in the same sense as the gas in the disk can become massive O(100Msun) &amp; undying! E.g.\nhttps://t.co/gC8kS1cRY7', ""Here we look at stars that move backwards through the AGN gas disk. They're ~ half the stars in the disk when it forms. These stars feel intense drag &amp; fall inwards fast (&lt;0.1Myr) through the disk towards the central supermassive black hole (SMBH). https://t.co/9YV45zRNQj"", 'As the population of backwards stars grows at small disk radii, due to starfall, interactions can occur, binaries can form &amp; scatterings can happen. Chaotic scatterings, particularly between binaries &amp; singles, can send stars rocketing towards the central shred zone. https://t.co/S59bpyUdIu', 'What happens next depends on the mass of the SMBH &amp; whether a star is flung to one side or the other of the SMBH....', 'If the star is sent too close to the SMBH (&lt;=100million Msun), the tidal forces across it cause it to rupture, spilling its guts at high speed around the SMBH &amp; into the inner disk, creating a tidal disruption event (TDE)', 'If the star is sent around the SMBH against the flow of gas, e.g. https://t.co/aO4BCzTsSJ', 'then the angular momentum of the unbound ejecta flung outwards cancels the angular momentum of the inner disk and causes much of the inner disk to slump onto the SMBH, clearing out a small cavity. https://t.co/4TtobVnGxn', 'The result is an over-luminous TDE (tidal disruption event), followed by a low AGN state afterwards as the disk recovers on the viscous timescale. Cartoon Lightcurve is: https://t.co/eXJDTISFN8', ""If the star goes the other way around the SMBH, the unbound ejecta adds angular momentum to the inner disk &amp; pushes it outwards temporarily. The result is a more 'normal' TDE, followed by a higher AGN state as the ejecta + inner disk accrete on the viscous timescale. Lightcurve: https://t.co/RYRsVctPn9"", ""We expect roughly equal numbers of these 'prograde' and 'retrograde' TDEs in AGN. Particularly early on as starfall allows this population to build up &amp; scatter in the inner disk. So, AGN TDEs are a nice probe of 'turning on' AGN."", 'Now we need to find AGN flares that look like this! Stay tuned.', 'With: @saavikford, @kantyellow, @AdamSJermyn, @doccosmos, Dan Stern, Nate Leigh, Taeho Ryu']",21,10,2226