text: 368,133,1257293116345921537,17373048,Rodrigo Nemmen,"New paper out: Jet efficiencies and black hole spins in jetted quasars, <LINK> where we estimate quasar powers from @NASAFermi observations, constrain how efficiently BHs convert accreted mass into outflows and estimate how fast they are spinning 1/4 Gamma-ray luminosities correlate with BH masses, so one could try to use gamma photons to have an idea of how massive a jetted quasar is. Good way to cross-check virial estimates 2/4 <LINK> Here we plot the lower limit on the jet efficiencies (what comes out/what goes in) as a function of BH mass. A few of the blazars are ""overpowered"" meaning that according to existing BH models they should not be possible: those four points above the line 3/4 <LINK> Finally, here is a distribution of BH spin lower limits for the sample. The spin is one of the two fundamental parameters of BH spacetimes besides mass (charge is unimportant). These guys are, unsurprisingly, rotating fast! 4/4 <LINK> paper led by @outflows (very appropriate user name!)",https://arxiv.org/abs/2005.00381,"The mechanisms responsible for the production of relativistic jets from supermassive black holes (SMBHs) accreting at near-Eddington rates are not well-understood. Simple theoretical expectations indicate that SMBHs in quasars accrete via thin discs which should produce at most very weak jets. This is contradicted by observations of powerful jets in flat-spectrum radio quasars (FSRQs). We use gamma-ray luminosities observed with the \emph{fermi} Large Area Telescope as a proxy of the jet power for a population of 154 FSRQs. Assuming typical quasar accretion rates and using black hole mass measurements from a variety of methods, we find a mean jet production efficiency of about 10 per cent for FSRQs, with values as high as 222 per cent. We find that this is consistent with FSRQs hosting moderately thin, magnetically arrested accretion discs around rapidly spinning black holes (BHs). Modeling our observations using general relativistic magnetohydrodynamic (GRMHD) simulations of jets from thin discs, we find an average lower limit of $a_* = 0.59$ for the SMBH spins of FSRQs, with tendency for the spins to decrease as the black hole mass increases. Our results are consistent with the merger-driven evolution of SMBHs. 3 per cent of the sample cannot be explained by current GRMHD models of jet production from Kerr BHs due to the high efficiencies. Along the way, we find a correlation between BH masses and $L_\gamma$ which may be an useful mass estimator in blazar gamma-ray studies. ",Jet efficiencies and black hole spins in jetted quasars,5,"['New paper out: Jet efficiencies and black hole spins in jetted quasars, <LINK>\nwhere we estimate quasar powers from @NASAFermi observations, constrain how efficiently BHs convert accreted mass into outflows and estimate how fast they are spinning 1/4', 'Gamma-ray luminosities correlate with BH masses, so one could try to use gamma photons to have an idea of how massive a jetted quasar is. Good way to cross-check virial estimates 2/4 https://t.co/n0ZmQACUVR', 'Here we plot the lower limit on the jet efficiencies (what comes out/what goes in) as a function of BH mass. A few of the blazars are ""overpowered"" meaning that according to existing BH models they should not be possible: those four points above the line 3/4 https://t.co/zCJotZT3xm', 'Finally, here is a distribution of BH spin lower limits for the sample. The spin is one of the two fundamental parameters of BH spacetimes besides mass (charge is unimportant).  These guys are, unsurprisingly, rotating fast! 4/4 https://t.co/mZpHwuZvf3', 'paper led by @outflows (very appropriate user name!)']",20,05,994