RELHIC
A RELHIC, or Reionization-Limited HI Cloud, is a theoretical construct in astrophysics that describes a type of dark matter halo containing neutral hydrogen gas.[1] These clouds are characterized by their potential to reveal the nature of dark matter and the conditions for galaxy formation in the early universe, particularly during the epoch of reionization. RELHICs are thought to be spherical gaseous systems that are in hydrostatic equilibrium and are influenced by both the presence of dark matter and a background ultraviolet radiation field from stars and galaxies.[1]
The concept of RELHICs was proposed by astrophysicists Alejandro Benitez-Llambay and Julio F. Navarro, as part of their work on cosmological simulations and observations.[1] They suggest that these structures could serve as observational targets to better understand the nature of dark matter and the formation of galaxies.
Recently, a RELHIC candidate, referred to as Cloud-9, was detected near the spiral galaxy Messier 94.[2][3][4][5]
References
[edit]- ^ a b c Benítez-Llambay, Alejandro; Navarro, Julio F.; Frenk, Carlos S.; Sawala, Till; Oman, Kyle; Fattahi, Azadeh; Schaller, Matthieu; Schaye, Joop; Crain, Robert A.; Theuns, Tom (2017-03-11). "The properties of 'dark' ΛCDM haloes in the Local Group". Monthly Notices of the Royal Astronomical Society. 465 (4): 3913–3926. doi:10.1093/mnras/stw2982. ISSN 0035-8711.
- ^ Zhou, Ruilei; Zhu, Ming; Yang, Yanbin; Yu, Haiyang; Yuan, Lixia; Jiang, Peng; Xi, Wenzhe (2023-08-01). "FAST Reveals New Evidence for M94 as a Merger". The Astrophysical Journal. 952 (2): 130. arXiv:2306.05080. Bibcode:2023ApJ...952..130Z. doi:10.3847/1538-4357/acdcf5. ISSN 0004-637X.
- ^ Benitez-Llambay, Alejandro; Navarro, Julio F. (2023-10-01). "Is a Recently Discovered H i Cloud near M94 a Starless Dark Matter Halo?". The Astrophysical Journal. 956 (1): 1. arXiv:2309.03253. Bibcode:2023ApJ...956....1B. doi:10.3847/1538-4357/acf767. ISSN 0004-637X.
- ^ Karunakaran, Ananthan; Spekkens, Kristine (2024-01-18). "A Bigger Cloud 9? New H i Observations of the RELHIC Candidate M94- Cloud 9". Research Notes of the AAS. 8 (1): 24. arXiv:2401.08765. Bibcode:2024RNAAS...8...24K. doi:10.3847/2515-5172/ad1ee6. ISSN 2515-5172.
- ^ Benítez-Llambay, Alejandro; Dutta, Rajeshwari; Fumagalli, Michele; Navarro, Julio F. (2024-09-01). "Examining the Nature of the Starless Dark Matter Halo Candidate Cloud-9 with Very Large Array Observations". The Astrophysical Journal. 973 (1): 61. Bibcode:2024ApJ...973...61B. doi:10.3847/1538-4357/ad65d9. ISSN 0004-637X.