Imprints of primordial magnetic fields on intrinsic alignments of galaxies
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_ | 1866911835282735104 |
|---|---|
| author | Saga, Shohei Shiraishi, Maresuke Akitsu, Kazuyuki Okumura, Teppei |
| author_facet | Saga, Shohei Shiraishi, Maresuke Akitsu, Kazuyuki Okumura, Teppei |
| contents | Primordial magnetic fields (PMFs) are one of the plausible candidates for the origin of the observed large-scale magnetic fields. While many proposals have been made for the generation mechanism of PMFs by earlier studies, it remains a subject of debate. In this paper, to obtain new insights into PMFs, we focus on the intrinsic alignments (IAs) of galaxies induced by the vector and tensor modes of the anisotropic stress of PMFs. The long-wavelength vector and tensor modes locally induce the tidal gravitational fields, leading to the characteristic distortions of the intrinsic ellipticity of galaxies. We investigate the shear E- and B-mode power spectra induced by the magnetic vector and tensor modes in the three-dimensional space, assuming the combination of galaxy imaging and galaxy redshift surveys. We find that the magnetic tensor mode dominates both the E- and B-mode spectra. In particular, the B-mode spectrum induced by the magnetic tensor mode plays a crucial role in constraining the amplitude of PMFs, even in the presence of the non-magnetic scalar contribution to the B-mode spectrum arising from the one-loop effect. In future galaxy redshift surveys, such as Euclid and Square Kilometre Array, the minimum detectable value reaches $\sim 30 \, \rm nG$, which can potentially get even smaller in proportion to the number of observed galaxies and reach $\sim \mathcal{O}(1 \, {\rm nG})$. Measuring the IAs of galaxies would be a potential probe for PMFs in future galaxy surveys. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2312_16316 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | Imprints of primordial magnetic fields on intrinsic alignments of galaxies Saga, Shohei Shiraishi, Maresuke Akitsu, Kazuyuki Okumura, Teppei Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology Primordial magnetic fields (PMFs) are one of the plausible candidates for the origin of the observed large-scale magnetic fields. While many proposals have been made for the generation mechanism of PMFs by earlier studies, it remains a subject of debate. In this paper, to obtain new insights into PMFs, we focus on the intrinsic alignments (IAs) of galaxies induced by the vector and tensor modes of the anisotropic stress of PMFs. The long-wavelength vector and tensor modes locally induce the tidal gravitational fields, leading to the characteristic distortions of the intrinsic ellipticity of galaxies. We investigate the shear E- and B-mode power spectra induced by the magnetic vector and tensor modes in the three-dimensional space, assuming the combination of galaxy imaging and galaxy redshift surveys. We find that the magnetic tensor mode dominates both the E- and B-mode spectra. In particular, the B-mode spectrum induced by the magnetic tensor mode plays a crucial role in constraining the amplitude of PMFs, even in the presence of the non-magnetic scalar contribution to the B-mode spectrum arising from the one-loop effect. In future galaxy redshift surveys, such as Euclid and Square Kilometre Array, the minimum detectable value reaches $\sim 30 \, \rm nG$, which can potentially get even smaller in proportion to the number of observed galaxies and reach $\sim \mathcal{O}(1 \, {\rm nG})$. Measuring the IAs of galaxies would be a potential probe for PMFs in future galaxy surveys. |
| title | Imprints of primordial magnetic fields on intrinsic alignments of galaxies |
| topic | Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology |
| url | https://arxiv.org/abs/2312.16316 |