Repeated Partial Disruptions in a White Dwarf–Neutron Star or White Dwarf–Black Hole Merger Modulate the Prompt Emission of Long-duration Merger-type GRBs
| Autor: | Junping Chen, Rong-Feng Shen, Wen-Jun Tan, Chen-Wei Wang, Shao-Lin Xiong, Run-Chao Chen, Bin-Bin Zhang |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2024 |
| Předmět: | |
| Zdroj: | The Astrophysical Journal Letters, Vol 973, Iss 1, p L33 (2024) |
| Druh dokumentu: | article |
| ISSN: | 2041-8213 2041-8205 |
| DOI: | 10.3847/2041-8213/ad7737 |
| Popis: | The progenitors of gamma-ray bursts (GRBs) have long been an unresolved issue. GRB 230307A stands out as an exceptionally bright event, belonging to the long-duration GRBs but also exhibiting a late-emission component reminiscent of a kilonova. Together with the similar events GRBs 060614 and 211211A, they make up a new subgroup of GRBs with intriguing progenitors. If such long-duration merger-type GRBs originated from the coalescence of a white dwarf (WD) with a neutron star (NS) or a black hole (BH), as proposed in the recent literature, then the larger tidal disruption radius of the WD, together with a nonnegligible residual orbital eccentricity, would make repeated partial tidal disruptions inevitable. This may modulate the mass accretion and jet launching process at the NS or BH, resulting in a quasiperiodic modulation (QPM) in the light curve of the GRB, with a period equal to the orbital period. The detection of potential QPMs during the early episode of prompt emission of these three GRBs supports this scenario, and the relatively slow QPM (> 1 s) suggests that the lighter object cannot be an NS. We propose that the progenitor system of GRBs 230307A, 060614, and 211211A consist of a WD of mass 1.3 M _⊙ , 0.9 M _⊙ , and 1.4 M _⊙ , respectively, and an NS (or BH). After several cycles of modulations, the WD is completely destroyed, and the accretion of the remaining debris dominates the extended emission episode. |
| Databáze: | Directory of Open Access Journals |
| Externí odkaz: |
|