Skip to main content

Foreground Subtraction and Signal reconstruction in redshifted 21cm Global Signal Experiments using Artificial Neural Networks

  • Madhurima Choudhury (a1) and Abhirup Datta (a1)

Observations of HI 21cm transition line is a promising probe into the Dark Ages and Epoch-of-Reionization. Detection of this redshifted 21cm signal is one of the key science goal for several upcoming low-frequency radio telescopes like HERA, SKA and DARE. Other global signal experiments include EDGES, LEDA, BIGHORNS, SCI-HI, SARAS. One of the major challenges for the detection of this signal is the accuracy of the foreground source removal. Several novel techniques have been explored already to remove bright foregrounds from both interferometric as well as total power experiments. Here, we present preliminary results from our investigation on application of ANN to detect 21cm global signal amidst bright galactic foreground. Following the formalism of representing the global 21cm signal by ’tanh’ model, this study finds that the global 21cm signal parameters can be accurately determined even in the presence of bright foregrounds represented by 3rd order log-polynomial or higher.

Hide All
Furlanetto, S. R., Oh, S. P. & Briggs, F. H. Cosmology at low frequencies: The 21 cm transition and the high-redshift Universe. Phys. Rep., 433: 181301, October 2006.
Barkana, R. & Loeb, A. A Method for Separating the Physics from the Astrophysics of High-Redshift 21 Centimeter Fluctuations. ApJL, 624: L65L68, May 2005.
Harker, G. J. A. Selection between foreground models for global 21-cm experiments. MNRAS, 449: L21L25, April 2015.
Pritchard, J., Ichiki, K., Mesinger, A., Metcalf, R. B., Pourtsidou, A., Santos, M., Abdalla, F. B., Chang, T. C., Chen, X., Weller, J. & Zaroubi, S. Cosmology from EoR/Cosmic Dawn with the SKA. Advancing Astrophysics with the Square Kilometre Array (AASKA14), art. 12, April 2015.
Shimabukuro, H. & Semelin, B. Analysing the 21 cm signal from the epoch of reionization with artificial neural networks. MNRAS, 468: 38693877, July 2017.
Mirocha, J., Harker, G. J. A. & Burns, J. O. Interpreting the Global 21-cm Signal from High Redshifts. II. Parameter Estimation for Models of Galaxy Formation. ApJ, 813: 11, November 2015.
Kingma, D. P. & Ba, J. Adam: A Method for Stochastic Optimization. ArXiv e-prints, December 2014.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Proceedings of the International Astronomical Union
  • ISSN: 1743-9213
  • EISSN: 1743-9221
  • URL: /core/journals/proceedings-of-the-international-astronomical-union
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed