Mass-gap strange quark stars in Vegh-type massive gravity with gravitationally decoupled dark matter
Physics of the Dark Universe, cilt.53, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 53
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.dark.2026.102417
- Dergi Adı: Physics of the Dark Universe
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, INSPEC
- Anahtar Kelimeler: Dark matter, Gravitational decoupling, Mass gap relation, Massive gravity, Quark stars
- İstanbul Üniversitesi Adresli: Evet
Özet
We construct a unified framework for anisotropic strange quark stars combining de Rham-Gabadadze-Tolley (dRGT)-like massive gravity with dark matter (DM) introduced via extended gravitational decoupling (EGD), in which both metric potentials are deformed by independent functions ξ ( r ) and h ( r ). Two DM density profiles are embedded in the decoupled θ -sector: the Einasto spike and the Bose–Einstein condensate (BEC). The baryonic sector is governed by the MIT bag model (quark-matter radial pressure pqr=(εq−4B)/3), while the pressure anisotropy is parametrized by the Horvat-Ilijic-Marunovic (HIM) prescription applied to the total effective radial pressure peffr. We show that the cooperative action of the graviton-mass coupling ( m 2 c 1 < 0) and the DM-induced modification of the effective pressure balance ( ρ E 0 or ρs≳50MeVfm−3), together with positive anisotropy ( β anis > 0), drives the maximum mass into the mass-gap window 2.5–5 M ⊙. The predicted GW190814 companion radii (12.3–12.8 km) and the PSR J0740+6620 radii (11.6–12.5 km) are consistent with NICER measurements. We verify the Harrison–Zel’dovich–Novikov stability criterion, the Chandrasekhar condition Γ > 4/3, the Herrera cracking condition |vt2−vr2|≤1, causality (vr2,vt2≤1) and all dominant energy conditions. We observe that the Buchdahl compactness bound 2 M / R < 8/9 employed here is the standard GR result. In the present dRGT-like massive gravity framework, the bound receives corrections that we estimate but do not derive in full generality, confirming physical self-consistency throughout the parameter space.