Line-of-Sight Anisotropies in the Cosmic Dawn and Epoch of Reionization 21-cm Power Spectrum
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The line-of-sight direction in the redshifted 21-cm signal coming from the cosmic dawn and the epoch of reionization is quite unique in many ways compared to any other cosmological signal. Different unique effects, such as the evolution history of the signal, non-linear peculiar velocities of the matter etc. will imprint their signature along the line-of-sight axis of the observed signal. One of the major goals of the future SKA-LOW radio interferometer is to observe the cosmic dawn and the epoch of reionization through this 21-cm signal. It is thus important to understand how these various effects affect the signal for its actual detection and proper interpretation. For more than one and half decades, various groups in India have been actively trying to understand and quantify the different line-of-sight effects that are present in this signal through analytical models and simulations. In many ways the importance of this sub-field under 21-cm cosmology have been identified, highlighted and pushed forward by the Indian community. In this article, we briefly describe their contribution and implication of these effects in the context of the future surveys of the cosmic dawn and the epoch of reionization that will be conducted by the SKA-LOW.
KeywordsMethods: statistical—cosmology: theory—dark ages, reionization, first stars—diffuse radiation.
The first author (SM) would like to acknowledge financial support from the European Research Council under the ERC grant number 638743-FIRSTDAWN and from the European Unions Seventh Framework Programme FP7-PEOPLE-2012-CIG, Grant No. 321933-21ALPHA. The second author (KKD) would like to thank University Grants Commission (UGC), India for support through UGC-Faculty Recharge Scheme (UGC-FRP) vide ref. no. F.4-5(137-FRP)/2014(BSR).
- Bowman, J. D. et al. 2013, Publ. Astron. Soc. Australia, 30, 31.Google Scholar
- Choudhuri, S., Bharadwaj, S., Ghosh, A., Ali, S. S. 2014, MNRAS, 445, 4351.Google Scholar
- Choudhuri, S., Bharadwaj, S., Roy, N., Ghosh, A., Ali, S. S., MNRAS (2016)Google Scholar
- Dillon, J. S. et al. 2014, Phys. Rev. D, 89, 023002.Google Scholar
- Fan, X. et al. 2003, Astron. J., 125, 1649.Google Scholar
- Ghara, R., Choudhury, T. R., Datta, K. K. 2015a, MNRAS, 447, 1806.Google Scholar
- Greig, B., Mesinger, A., Koopmans, L. V. E. 2015, preprint (arXiv:1509.03312).
- Hamilton, A. J. S. 1998, in: Astrophysics and Space Science Library, edited by D. Hamilton, vol. 231, The Evolving Universe, p. 185 (arXiv:astro-ph/9708102).
- Komatsu, E. et al. 2011, ApJS, 192, 18.Google Scholar
- Koopmans, L. et al. 2015, Advancing Astrophysics with the Square Kilometre Array (AASKA14), p. 1.Google Scholar
- Majumdar, S. et al. 2016, MNRAS, 456, 2080.Google Scholar
- Mellema, G., Koopmans, L., Shukla, H., Datta, K. K., Mesinger, A., Majumdar, S. 2015, Advancing Astrophysics with the Square Kilometre Array (AASKA14), p. 10.Google Scholar
- Mondal, R., Bharadwaj, S., Majumdar, S. 2016a, preprint, (arXiv:1606.03874).
- Paciga, G. et al. 2013, MNRAS, 433, 639.Google Scholar
- Planck Collaboration 2015, preprint (arXiv:1502.01589).
- Tingay, S. J. et al. 2013, Publ. Astron. Soc. Australia, 30, 7.Google Scholar
- van Haarlem, M. P. et al. 2013, A&A, 556, A2.Google Scholar