TY - JOUR
T1 - First multi-redshift limits on post-epoch of reionization 21cm signal from z = 1.96-3.58 Using uGMRT
AU - Chakraborty, Arnab
AU - Datta, Abhirup
AU - Roy, Nirupam
AU - Bharadwaj, Somnath
AU - Choudhury, Tirthankar Roy
AU - Datta, Kanan K.
AU - Pal, Srijita
AU - Choudhury, Madhurima
AU - Choudhuri, Samir
AU - Dutta, Prasun
AU - Sarkar, Debanjan
N1 - Funding Information:
run by National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. A.C. would like to thank DST for INSPIRE fellowship. A.D. would like to acknowledge the support of EMR-II under CSIR No. 03(1461)/19.
Publisher Copyright:
© 2021. The American Astronomical Society.
PY - 2021/1/20
Y1 - 2021/1/20
N2 - Measurement of fluctuations in diffuse HI 21 cm background radiation from the post-reionization epoch (z ≤ 6) is a promising avenue to probe the large-scale structure of the universe and understand the evolution of galaxies. We observe the European Large Area ISO Survey-North 1 (ELAIS-N1) field at 300-500 MHz using the upgraded Giant Meterwave Radio Telescope (uGMRT) and employ the "foreground avoidance"technique to estimate the HI 21 cm power spectrum in the redshift range z = 1.96-3.58. Given the possible systematics that may remain in the data, we find the most stringent upper limits on the spherically averaged 21 cm power spectra at k ∼ 1.0 Mpc-1 are (58.87 mK)2, (61.49 mK)2, (60.89 mK)2, and (105.85 mK)2 at z = 1.96, 2.19, 2.62, and 3.58, respectively. We use this to constrain the product of neutral HI mass density (ΩHI) and HI bias (bHI) to the underlying dark matter density field, [ΩHIbHI], as 0.09, 0.11, 0.12, and 0.24 at z = 1.96, 2.19, 2.62, and 3.58, respectively. To the best of our knowledge these are the first limits on the HI 21 cm power spectra at the redshift range z = 1.96-3.58 and would play a significant role to constrain the models of galaxy formation and evolution.
AB - Measurement of fluctuations in diffuse HI 21 cm background radiation from the post-reionization epoch (z ≤ 6) is a promising avenue to probe the large-scale structure of the universe and understand the evolution of galaxies. We observe the European Large Area ISO Survey-North 1 (ELAIS-N1) field at 300-500 MHz using the upgraded Giant Meterwave Radio Telescope (uGMRT) and employ the "foreground avoidance"technique to estimate the HI 21 cm power spectrum in the redshift range z = 1.96-3.58. Given the possible systematics that may remain in the data, we find the most stringent upper limits on the spherically averaged 21 cm power spectra at k ∼ 1.0 Mpc-1 are (58.87 mK)2, (61.49 mK)2, (60.89 mK)2, and (105.85 mK)2 at z = 1.96, 2.19, 2.62, and 3.58, respectively. We use this to constrain the product of neutral HI mass density (ΩHI) and HI bias (bHI) to the underlying dark matter density field, [ΩHIbHI], as 0.09, 0.11, 0.12, and 0.24 at z = 1.96, 2.19, 2.62, and 3.58, respectively. To the best of our knowledge these are the first limits on the HI 21 cm power spectra at the redshift range z = 1.96-3.58 and would play a significant role to constrain the models of galaxy formation and evolution.
UR - http://www.scopus.com/inward/record.url?scp=85100309779&partnerID=8YFLogxK
U2 - 10.3847/2041-8213/abd17a
DO - 10.3847/2041-8213/abd17a
M3 - Article
AN - SCOPUS:85100309779
SN - 2041-8205
VL - 907
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 1
M1 - abd17a
ER -