| Name: | Keerthipriya Sathish |
| Affiliation: | Raman Research institute |
| Conference ID: | ASI2025_422 |
| Title: | Dual polarised Fantail dipole Antenna Design for APSERa an S-band Precision cosmology experiment |
| Authors: | Keerthipriya Sathish 1, Mayuri Sathyanarayana Rao 2, Debdeep Sarkar 3 |
| Authors Affiliation: | Keerthipriya Sathish (Raman Research Institute, Bangalore-560080, and Indian Institute of Science - 560012)
Mayuri Sathyanarayana Rao (Raman Research Institute, Bangalore -560080)
Debdeep Sarkar (Indian Institute of Science, Bangalore -560012) |
| Mode of Presentation: | Oral |
| Abstract Category: | Facilities, Technologies and Data science |
| Abstract: | The Cosmic Microwave Background (CMB) radiation serves as a critical source of information in understanding the evolution and composition of our Universe. Theoretical predictions suggest the presence of inevitable faint deviations referred to as ‘spectral distortions’ in the CMB spectrum from that of a blackbody. One such distortion is the cosmological recombination radiation (CRR), originating from photons emitted during the formation of hydrogen and helium atoms in the Epoch of Recombination (ERA) (redshifts 900 < z < 8000) in the early universe. In this work, we present a novel scalable broadband dual polarised fantail shaped dipole antenna design motivated by the detection of these distortions within the 2.5–4 GHz range. The antenna has a sensitivity of the order of 1 part in 10^3 over the entire frequency band, offering a sensitivity improvement of over an order of magnitude compared to standard broadband antennas. This sensitivity was validated through a custom-designed pipeline that emulates the convolution and interaction of the sky and ground with the antenna's beam pattern and return loss. While it does not yet achieve the sensitivity required for direct detection of cosmological recombination radiation, the antenna fulfills essential design criteria for experiments targeting absolute sky spectrum measurements at millikelvin level. This can aid in refining foreground models for global detection experiments, and also address the problem of excess radio background at 3.3GHz reported by ARCADE-2 experiment. |
