TY  - JOUR
AU  - Baeza-Ballesteros, J.
AU  - Copeland, E. J.
AU  - Figueroa, D. G.
AU  - Lizarraga, J.
PY  - 2024
DA  - 2024//
TI  - Gravitational wave emission from a cosmic string loop: Global case
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 043522
EP  - 12pp
VL  - 110
IS  - 4
PB  - Amer Physical Soc
AB  - We study the simultaneous decay of global string loops into scalar particles (massless and massive modes) and gravitational waves (GWs). Using field-theory simulations in flat space-time of isolated loops with initial length similar to 80-1700 times their core width, we determine the power emitted into scalar particles, P phi , and GWs, P GW , and characterize the loop-decay timescale as a function of its initial length, energy, and angular momentum. We quantify infrared and ultraviolet lattice dependencies of our results. For all type of loops and initial conditions considered, GW emission is always suppressed compared to particles as P GW /P phi approximate to O(10)(v/mp)2 ( 10 )( v/m p ) 2 << 1, where v is the vacuum expectation value associated with string formation. These conclusions are robust for the length-to-width ratios considered, with no indication they should change if the ratio is increased. The results suggest that the GW background from a global string network, such as in dark-matter axion scenarios, will be suppressed compared to previous expectations.
SN  - 2470-0010
UR  - https://arxiv.org/abs/2308.08456
UR  - https://doi.org/10.1103/PhysRevD.110.043522
DO  - 10.1103/PhysRevD.110.043522
LA  - English
N1  - WOS:001381346400003
ID  - Baeza-Ballesteros_etal2024
ER  -