text: 118,134,1228253588771737601,971035265933479936,Josu C. Aurrekoetxea,"New paper with Thomas Helfer (@Thomas_Italy) and Eugene Lim (@tukohbin)! Coherent Gravitational Waveforms and Memory from Cosmic String Loops  <LINK> <LINK> @Thomas_Italy @tukohbin We construct, for the first time, the time-domain gravitational wave strain waveform from the collapse of a strongly gravitating Abelian Higgs cosmic string loop in full general relativity.  Here is a summary video we put on YouTube: <LINK> @Thomas_Italy @tukohbin We found that the strain exhibits a large memory effect during merger, ending with a burst and the characteristic ringdown as a black hole is formed. <LINK> @Thomas_Italy @tukohbin We think the nature of this memory arises from the fact that post-merger, there is a loss of matter emitted axially in ultra-relativistic jets – and hence is highly aspherical. Check these jets in this video: <LINK> @Thomas_Italy @tukohbin We also investigated the waveform and energy emitted as a function of string width, loop radius and string tension Gμ and we found that while it doesnt show a strong dependence on the width and loop radius, the lighter the strings (lower Gμ), the **more** GWs! <LINK> @Thomas_Italy @tukohbin These are ultra-relativistic events, the BH forms when the loop is moving at speed v &gt; 0.99c (see the Lorentz contraction in the previous video). We believe that E_GW is dominated by kinematics since lower tension loops collapse at higher velocities (\gamma &gt; 40!)",https://arxiv.org/abs/2002.05177,"We construct, for the first time, the time-domain gravitational wave strain waveform from the collapse of a strongly gravitating Abelian Higgs cosmic string loop in full general relativity. We show that the strain exhibits a large memory effect during merger, ending with a burst and the characteristic ringdown as a black hole is formed. Furthermore, we investigate the waveform and energy emitted as a function of string width, loop radius and string tension $G\mu$. We find that the mass normalized gravitational wave energy displays a strong dependence on the inverse of the string tension $E_{\mathrm{GW}}/M_0\propto 1/G\mu$, with $E_{\mathrm{GW}}/M_0 \sim {\cal O}(1)\%$ at the percent level, for the regime where $G\mu\gtrsim10^{-3}$. Conversely, we show that the efficiency is only weakly dependent on the initial string width and initial loop radii. Using these results, we argue that gravitational wave production is dominated by kinematical instead of geometrical considerations. ",Coherent Gravitational Waveforms and Memory from Cosmic String Loops,6,"['New paper with Thomas Helfer (@Thomas_Italy) and Eugene Lim (@tukohbin)! Coherent Gravitational Waveforms and Memory from Cosmic String Loops \n \n<LINK> <LINK>', '@Thomas_Italy @tukohbin We construct,  for the first time,  the time-domain gravitational wave strain waveform from the collapse  of  a  strongly  gravitating  Abelian  Higgs  cosmic  string  loop  in  full  general  relativity.\n \nHere is a summary video we put on YouTube: https://t.co/lLoi5r7JHl', '@Thomas_Italy @tukohbin We found  that  the  strain  exhibits  a  large  memory  effect  during  merger,  ending  with  a  burst  and  the characteristic ringdown as a black hole is formed. https://t.co/idZkuyBOio', '@Thomas_Italy @tukohbin We think the nature  of  this  memory  arises  from  the fact that post-merger, there is a loss of matter emitted axially in ultra-relativistic jets – and hence is highly aspherical.\n\nCheck these jets in this video: https://t.co/qPJoIwzBnx', '@Thomas_Italy @tukohbin We also investigated the waveform and energy emitted  as a function of string width, loop radius and string  tension Gμ and we found that while it doesnt show a strong dependence on the width and loop radius, the lighter the strings (lower Gμ), the **more** GWs! https://t.co/lCUZDISJ5h', '@Thomas_Italy @tukohbin These are ultra-relativistic events, the BH forms when the loop is moving at speed v &gt; 0.99c (see the Lorentz contraction in the previous video). We believe that E_GW is dominated by kinematics since lower tension loops collapse at higher velocities (\\gamma &gt; 40!)']",20,02,1429