Browsing by Author "Ghosh, Abhik"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    All-sky angular power spectrum – I. Estimating brightness temperature fluctuations using the 150-MHz TGSS survey
    (Oxford University Press, 2020) Ghosh, Abhik; Choudhuri, Samir; Roy, Nirupam
    Measurements of the Galactic synchrotron emission are important for the 21-cm studies of the epoch of reionization. The study of synchrotron emission is also useful for quantifying the fluctuations in the magnetic field and the cosmic-ray electron density of the turbulent interstellar medium (ISM) of our Galaxy. Here, we present the all-sky angular power spectrum (Cℓ) measurements of the diffuse synchrotron emission obtained using the TIFR GMRT Sky Survey (TGSS) at 150 MHz.
  • Thumbnail Image
    Item
    Foreground modelling via Gaussian process regression: an application to HERA data
    (Oxford University Press, 2020) Ghosh, Abhik; Mertens, Florent; Bernardi, Gianni
    The key challenge in the observation of the redshifted 21-cm signal from cosmic reionization is its separation from the much brighter foreground emission. Such separation relies on the different spectral properties of the two components, although, in real life, the foreground intrinsic spectrum is often corrupted by the instrumental response, inducing systematic effects that can further jeopardize the measurement of the 21-cm signal. In this paper, we use Gaussian Process Regression to model both foreground emission and instrumental systematics in ∼2 h of data from the Hydrogen Epoch of Reionization Array.