The monopole and quadrupole moments of the Epoch of Reionization (EoR) 21-cm bispectrum
Fuente:
arXiv
Salvato in:
| Autori principali: | , , , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2023
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866916089865175040 |
|---|---|
| author | Gill, Sukhdeep Singh Pramanick, Suman Bharadwaj, Somnath Shaw, Abinash Kumar Majumdar, Suman |
| author_facet | Gill, Sukhdeep Singh Pramanick, Suman Bharadwaj, Somnath Shaw, Abinash Kumar Majumdar, Suman |
| contents | We study the monopole ($\bar{B}^0_0$) and quadrupole ($\bar{B}^0_2$) moments of the 21-cm bispectrum (BS) from EoR simulations and present results for squeezed and stretched triangles. Both $\bar{B}^0_0$ and $\bar{B}^0_2$ are positive at the early stage of EoR where the mean neutral hydrogen (HI) density fraction $\bar{x}_{\rm HI} \approx 0.99$. The subsequent evolution of $\bar{B}^0_0$ and $\bar{B}^0_2$ at large and intermediate scales $(k=0.29$ and $0.56 \, {\rm Mpc}^{-1}$ respectively) is punctuated by two sign changes which mark transitions in the HI distribution. The first sign flip where $\bar{B}^0_0$ becomes negative occurs in the intermediate stages of EoR $(\bar{x}_{\rm HI} > 0.5)$, at large scale first followed by the intermediate scale. This marks the emergence of distinct ionized bubbles in the neutral background. $\bar{B}^0_2$ is relatively less affected by this transition, and it mostly remains positive even when $\bar{B}^0_0$ becomes negative. The second sign flip, which affects both $\bar{B}^0_0$ and $\bar{B}^0_2$, occurs at the late stage of EoR $(\bar{x}_{\rm HI} < 0.5)$. This marks a transition in the topology of the HI distribution, after which we have distinct HI islands in an ionized background. This causes $\bar{B}^0_0$ to become positive. The negative $\bar{B}^0_2$ is a definite indication that the HI islands survive only in under-dense regions. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2310_15579 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | The monopole and quadrupole moments of the Epoch of Reionization (EoR) 21-cm bispectrum Gill, Sukhdeep Singh Pramanick, Suman Bharadwaj, Somnath Shaw, Abinash Kumar Majumdar, Suman Cosmology and Nongalactic Astrophysics We study the monopole ($\bar{B}^0_0$) and quadrupole ($\bar{B}^0_2$) moments of the 21-cm bispectrum (BS) from EoR simulations and present results for squeezed and stretched triangles. Both $\bar{B}^0_0$ and $\bar{B}^0_2$ are positive at the early stage of EoR where the mean neutral hydrogen (HI) density fraction $\bar{x}_{\rm HI} \approx 0.99$. The subsequent evolution of $\bar{B}^0_0$ and $\bar{B}^0_2$ at large and intermediate scales $(k=0.29$ and $0.56 \, {\rm Mpc}^{-1}$ respectively) is punctuated by two sign changes which mark transitions in the HI distribution. The first sign flip where $\bar{B}^0_0$ becomes negative occurs in the intermediate stages of EoR $(\bar{x}_{\rm HI} > 0.5)$, at large scale first followed by the intermediate scale. This marks the emergence of distinct ionized bubbles in the neutral background. $\bar{B}^0_2$ is relatively less affected by this transition, and it mostly remains positive even when $\bar{B}^0_0$ becomes negative. The second sign flip, which affects both $\bar{B}^0_0$ and $\bar{B}^0_2$, occurs at the late stage of EoR $(\bar{x}_{\rm HI} < 0.5)$. This marks a transition in the topology of the HI distribution, after which we have distinct HI islands in an ionized background. This causes $\bar{B}^0_0$ to become positive. The negative $\bar{B}^0_2$ is a definite indication that the HI islands survive only in under-dense regions. |
| title | The monopole and quadrupole moments of the Epoch of Reionization (EoR) 21-cm bispectrum |
| topic | Cosmology and Nongalactic Astrophysics |
| url | https://arxiv.org/abs/2310.15579 |