Nuclear Physics Seminar- Violetta Sagun (University of Southampton)- Constraining the deconfinement phase transition properties at zero temperature with the fastest spinning millisecond pulsars

Outside of the PRB with sun shining and students walking past.
March 25, 2025
2:00PM - 3:00PM
4138 Physics Research Building

Date Range
2025-03-25 14:00:00 2025-03-25 15:00:00 Nuclear Physics Seminar- Violetta Sagun (University of Southampton)- Constraining the deconfinement phase transition properties at zero temperature with the fastest spinning millisecond pulsars Dr. Violetta SagunSenior Researcher in Theoretical Astrophysics, University of SouthamptonConstraining the deconfinement phase transition properties at zero temperature with the fastest spinning millisecond pulsarsLocation: 4138 Physics Research BuildingFaculty Host: TBD Abstract: We study rotating hybrid stars, with a particular emphasis on the effect of a deconfinement phase transition on their properties at high spin. Our analysis is based on a hybrid equation of state with a phase transition from hypernuclear matter to color-superconducting quark matter, where both phases are described within a relativistic density functional approach. By varying the vector meson and diquark couplings in the quark matter phase, we obtain different hybrid star sequences with varying extensions of the quark matter core, ensuring consistency with astrophysical constraints from mass, radius, and tidal deformability measurements. We test whether the early deconfinement phase transition is consistent with the present observational data. We show how the fastest spinning pulsars and the appearance of the quasi-radial oscillations and non-axisymmetric instabilities constrain the strongly interacting matter equation of state at zero temperature. Our findings reveal that incorporating the hybrid equation of state into the analysis of pulsars has significant implications for the constraints on the properties of strongly interacting matter and neutron stars. 4138 Physics Research Building America/New_York public

Dr. Violetta Sagun

Senior Researcher in Theoretical Astrophysics, University of Southampton

Constraining the deconfinement phase transition properties at zero temperature with the fastest spinning millisecond pulsars

Location: 4138 Physics Research Building

Faculty Host: TBD

 

Abstract: We study rotating hybrid stars, with a particular emphasis on the effect of a deconfinement phase transition on their properties at high spin. Our analysis is based on a hybrid equation of state with a phase transition from hypernuclear matter to color-superconducting quark matter, where both phases are described within a relativistic density functional approach. By varying the vector meson and diquark couplings in the quark matter phase, we obtain different hybrid star sequences with varying extensions of the quark matter core, ensuring consistency with astrophysical constraints from mass, radius, and tidal deformability measurements. We test whether the early deconfinement phase transition is consistent with the present observational data. We show how the fastest spinning pulsars and the appearance of the quasi-radial oscillations and non-axisymmetric instabilities constrain the strongly interacting matter equation of state at zero temperature. Our findings reveal that incorporating the hybrid equation of state into the analysis of pulsars has significant implications for the constraints on the properties of strongly interacting matter and neutron stars.