Revisiting lifetimes of doubly charmed baryons

We present updated predictions for lifetimes of doubly charmed baryons, within the heavy quark expansion, including available NLO $\alpha_s$ contributions and newly-computed terms in the $1/m_c$ series. Our improved results confirm the expected hierarchy $$\tau(\Xi_{cc}^{+}) < \tau(\Omega_{cc}^{+}) < \tau(\Xi_{cc}^{++}) \,,$$ while the predicted lifetime $\tau(\Xi_{cc}^{++}) = 0.32 \pm 0.5 ^{+0.8}_{-0.7} \,\textrm{ps}$ is consistent with the recent LHCb determination. We provide predictions for the lifetime ratios of the $\Xi_{cc}^{+}$ and $\Omega_{cc}^+$ baryons relative to the $\Xi_{cc}^{++}$ baryon, namely $\tau(\Xi_{cc}^{+})/\tau(\Xi_{cc}^{++})=0.22\pm 0.05\pm 0.04$ and $\tau(\Omega_{cc}^{+})/\tau(\Xi_{cc}^{++})=0.52\pm 0.13^{+0.03}_{-0.02}$.Comment: 25 pages, 2 figures; v2: few clarifications added, one reference added, matches version accepted for publicatio

Quasinormal modes of black holes

Prostorvremena crnih rupa stabilna su rješenja Einsteinove jednadžbe. Uslijed neke perturbacije one će se vratiti u prvobitno stanje prilikom čega će izgubiti dio energije zračenjem gravitacijskih valova. Svojstveni načini titranja disipativnih sustava, stoga i crnih rupa, nazivaju se kvazinormalni modovi. U ovome radu dan je teorijski pregled kvazinormalnih modova kroz teoriju perturbacija crnih rupa. U prvom ne iščezavajućem redu promotrena je dinamika perturbacije prostorvremena te dinamika skalarnih i vektorskih polja uronjenih u pozadinsko prostorvrijeme Schwarzschildove crne rupe. Proučeno je nekoliko poznatih, aproksimativnih i egzaktnih, metoda računanja kvazinormalnih modova te su njihovi rezultati također i reproducirani.Black hole spacetimes are stable solutions to Einstein’s equations. After a perturbation they will return to their equilibrium state during which they will lose energy through gravitational radiation. Eigenmodes of dissipative systems, including black holes, are called quasinormal modes. In this thesis, a theoretical overview of quasinormal modes is given through black hole perturbation theory. The dynamics of spacetime perturbations, as well as scalar and vector field dynamics in Schwarzschild spacetime is analysed in leading order of perturbation theory. A couple of well-known, approximative and exact, methods of calculating quasinormal modes is given and their results are reproduced

Quasinormal modes of black holes

Prostorvremena crnih rupa stabilna su rješenja Einsteinove jednadžbe. Uslijed neke perturbacije one će se vratiti u prvobitno stanje prilikom čega će izgubiti dio energije zračenjem gravitacijskih valova. Svojstveni načini titranja disipativnih sustava, stoga i crnih rupa, nazivaju se kvazinormalni modovi. U ovome radu dan je teorijski pregled kvazinormalnih modova kroz teoriju perturbacija crnih rupa. U prvom ne iščezavajućem redu promotrena je dinamika perturbacije prostorvremena te dinamika skalarnih i vektorskih polja uronjenih u pozadinsko prostorvrijeme Schwarzschildove crne rupe. Proučeno je nekoliko poznatih, aproksimativnih i egzaktnih, metoda računanja kvazinormalnih modova te su njihovi rezultati također i reproducirani.Black hole spacetimes are stable solutions to Einstein’s equations. After a perturbation they will return to their equilibrium state during which they will lose energy through gravitational radiation. Eigenmodes of dissipative systems, including black holes, are called quasinormal modes. In this thesis, a theoretical overview of quasinormal modes is given through black hole perturbation theory. The dynamics of spacetime perturbations, as well as scalar and vector field dynamics in Schwarzschild spacetime is analysed in leading order of perturbation theory. A couple of well-known, approximative and exact, methods of calculating quasinormal modes is given and their results are reproduced

Quasinormal modes of black holes

Prostorvremena crnih rupa stabilna su rješenja Einsteinove jednadžbe. Uslijed neke perturbacije one će se vratiti u prvobitno stanje prilikom čega će izgubiti dio energije zračenjem gravitacijskih valova. Svojstveni načini titranja disipativnih sustava, stoga i crnih rupa, nazivaju se kvazinormalni modovi. U ovome radu dan je teorijski pregled kvazinormalnih modova kroz teoriju perturbacija crnih rupa. U prvom ne iščezavajućem redu promotrena je dinamika perturbacije prostorvremena te dinamika skalarnih i vektorskih polja uronjenih u pozadinsko prostorvrijeme Schwarzschildove crne rupe. Proučeno je nekoliko poznatih, aproksimativnih i egzaktnih, metoda računanja kvazinormalnih modova te su njihovi rezultati također i reproducirani.Black hole spacetimes are stable solutions to Einstein’s equations. After a perturbation they will return to their equilibrium state during which they will lose energy through gravitational radiation. Eigenmodes of dissipative systems, including black holes, are called quasinormal modes. In this thesis, a theoretical overview of quasinormal modes is given through black hole perturbation theory. The dynamics of spacetime perturbations, as well as scalar and vector field dynamics in Schwarzschild spacetime is analysed in leading order of perturbation theory. A couple of well-known, approximative and exact, methods of calculating quasinormal modes is given and their results are reproduced

Revisiting lifetimes of doubly charmed baryons

Abstract We present updated predictions for lifetimes of doubly charmed baryons, within the heavy quark expansion, including available NLO α s contributions and newly-computed terms in the 1/m c series. Our improved results confirm the expected hierarchy τ Ξ cc + < τ Ω cc + < τ Ξ cc + + , $$\tau \left({\Xi}_{cc}^{+}\right)<\tau \left({\Omega}_{cc}^{+}\right)<\tau \left({\Xi}_{cc}^{++}\right),$$ while the predicted lifetime τ Ξ cc + + $$\tau \left({\Xi}_{cc}^{++}\right)$$ = 0.32 ± 0.5 − 0.7 + 0.8 $${0.5}_{-0.7}^{+0.8}$$ ps is consistent with the recent LHCb determination. We provide predictions for the lifetime ratios of the Ξ cc + $${\Xi}_{cc}^{+}$$ and Ω cc + $${\Omega}_{cc}^{+}$$ baryons relative to the Ξ cc + + $${\Xi}_{cc}^{++}$$ baryon, namely τ Ξ cc + / τ Ξ cc + + $$\tau \left({\Xi}_{cc}^{+}\right)/\tau \left({\Xi}_{cc}^{++}\right)$$ = 0.22 ± 0.05 ± 0.04 and τ Ω cc + / τ Ξ cc + + $$\tau \left({\Omega}_{cc}^{+}\right)/\tau \left({\Xi}_{cc}^{++}\right)$$ = 0.52 ± 0.13 − 0.02 + 0.03 $${0.13}_{-0.02}^{+0.03}$$