| Abstract: | The redshifted 21-cm signal from neutral hydrogen is a crucial probe for studying the early Universe, spanning the Cosmic Dawn (CD) to the Epoch of Reionization (EoR). Detecting this faint signal at low radio frequencies is highly challenging due to dominant foregrounds—galactic and extragalactic, ionospheric distortions, radio frequency interference (RFI), and instrumental systematics. Despite these challenges, ground-based telescopes such as LOFAR, MWA, and HERA have made significant progress, bringing the detection of this cosmological signal within reach. In this work, we present observations of the ELAIS-N1 field at Band-2 (120–250 MHz) using the upgraded GMRT, a pathfinder for the SKA. With 32 hours of observations covering a bandwidth of around 100 MHz, we achieved an off-source RMS noise level of 237 μJy/beam and an angular resolution of 11.45 arcseconds in the final image. Our catalog comprises 1027 sources with a flux density threshold of 5σ at a central frequency of 183 MHz. We have derived the source count from this catalog, which is consistent with other observations at different frequencies. We are presenting the first constraints on the 21-cm signal at high redshift z = 9, using the foreground removal technique to mitigate foregrounds. These results are preliminary and demonstrate the capabilities of uGMRT in probing the cosmic HI signal from EoR.
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