Recent submissions 

espace: Recent submissions

Now showing items 2881-2890 of 76072

    • Impact of station far sidelobes on EoR/CD power spectra
      Trott, Cathryn (2022)
      Stations of dipole antennas for SKA1-Low will comprise 256 elements spread over an area with a diameter of 38 m. We consider the effect of residual unsubtracted sources well outside of the main beam for differing numbers ...
    • Constraining the 21 cm brightness temperature of the IGM at z = 6.6 around LAEs with the murchison widefield array
      Trott, Cathryn ; Jordan, Chris ; Line, J.L.B.; Lynch, Christene ; Yoshiura, S.; McKinley, Ben ; Dayal, P.; Pindor, B.; Hutter, A.; Takahashi, K.; Wayth, Randall ; Barry, Nichole ; Beardsley, A.; Bowman, J.; Byrne, R.; Chokshi, A.; Greig, B.; Hasegawa, K.; Hazelton, B.J.; Howard, E.; Jacobs, D.; Kolopanis, M.; Mitchell, D.A.; Morales, M.F.; Murray, Steven ; Pober, J.C.; Rahimi, M.; Tingay, Steven ; Webster, R.L.; Wilensky, M.; Wyithe, J.S.B.; Zheng, Q. (2021)
      The locations of Ly α-emitting galaxies (LAEs) at the end of the Epoch of Reionization (EoR) are expected to correlate with regions of ionized hydrogen, traced by the redshifted 21 cm hyperfine line. Mapping the neutral ...
    • A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17
      Yoshiura, S.; Pindor, B.; Line, J.L.B.; Barry, Nichole ; Trott, Cathryn ; Beardsley, A.; Bowman, J.; Byrne, R.; Chokshi, A.; Hazelton, B.J.; Hasegawa, K.; Howard, E.; Greig, B.; Jacobs, D.; Jordan, Chris ; Joseph, R.; Kolopanis, M.; Lynch, Christene ; McKinley, Ben ; Mitchell, D.A.; Morales, M.F.; Murray, Steven ; Pober, J.C.; Rahimi, M.; Takahashi, K.; Tingay, Steven ; Wayth, Randall ; Webster, R.L.; Wilensky, M.; Wyithe, J.S.B.; Zhang, Z.; Zheng, Q. (2021)
      Observations in the lowest Murchison Widefield Array (MWA) band between 75 and 100 MHz have the potential to constrain the distribution of neutral hydrogen in the intergalactic medium at redshift ∼13-17. Using 15 h of MWA ...
    • Simulations of ionospheric refraction on radio interferometric data
      Chege, J Kariuki; Jordan, Chris ; Lynch, Christene ; Line, Jack ; Trott, Cathryn (2021)
      The Epoch of Reionisation (EoR) is the period within which the neutral universe transitioned to an ionised one. This period remains unobserved using low-frequency radio interferometers which target the 21 cm signal of ...
    • The impact of tandem redundant/sky-based calibration in MWA Phase II data analysis
      Zhang, Z.; Pober, J.C.; Li, W.; Hazelton, B.J.; Morales, M.F.; Trott, Cathryn ; Jordan, Chris ; Joseph, R.C.; Beardsley, A.; Barry, N.; Byrne, R.; Tingay, Steven ; Chokshi, A.; Hasegawa, K.; Jacobs, D.C.; Lanman, A.; Line, Jack ; Lynch, Christene ; McKinley, Ben ; Mitchell, D.A.; Murray, Steven ; Pindor, B.; Rahimi, M.; Takahashi, K.; Wayth, Randall ; Webster, R.L.; Wilensky, M.; Yoshiura, S.; Zheng, Q. (2020)
      Precise instrumental calibration is of crucial importance to 21-cm cosmology experiments. The Murchison Widefield Array's (MWA) Phase II compact configuration offers us opportunities for both redundant calibration and ...
    • Exploring reionization and high-z galaxy observables with recent multiredshift MWA upper limits on the 21-cm signal
      Greig, B.; Trott, Cathryn ; Barry, Nichole ; Mutch, S.J.; Pindor, B.; Webster, R.L.; Wyithe, J.S.B. (2021)
      We use the latest multiredshift (z = 6.5-8.7) upper limits on the 21-cm signal from the Murchison Widefield Array (MWA) to explore astrophysical models which are inconsistent with the data. We explore these limits in the ...
    • Modelling and peeling extended sources with shapelets: A Fornax A case study
      Line, Jack ; Mitchell, D.A.; Pindor, B.; Riding, J.L.; McKinley, Ben ; Webster, R.L.; Trott, Cathryn ; Hurley-Walker, Natasha ; Offringa, A.R. (2020)
      To make a power spectrum (PS) detection of the 21-cm signal from the Epoch of Reionisation (EoR), one must avoid/subtract bright foreground sources. Sources such as Fornax A present a modelling challenge due to spatial ...
    • The bispectrum and 21-cm foregrounds during the Epoch of Reionization
      Watkinson, C.A.; Trott, Cathryn ; Hothi, I. (2021)
      Numerous studies have established the theoretical potential of the 21-cm bispectrum to boost our understanding of the Epoch of Reionization (EoR). We take a first look at the impact of foregrounds (FGs) and instrumental ...
    • Calibration and 21-cm power spectrum estimation in the presence of antenna beam variations
      Joseph, R.C.; Trott, Cathryn ; Wayth, Randall ; Nasirudin, A. (2020)
      Detecting a signal from the Epoch of Reionization (EoR) requires an exquisite understanding of Galactic and extragalactic foregrounds, low-frequency radio instruments, instrumental calibration, and data analysis pipelines. ...
    • First Season MWA Phase II Epoch of Reionization Power Spectrum Results at Redshift 7
      Li, W.; Pober, J.C.; Barry, N.; Hazelton, B.J.; Morales, M.F.; Trott, Cathryn ; Lanman, A.; Wilensky, M.; Sullivan, I.; Beardsley, A.P.; Booler, Tom ; Bowman, J.D.; Byrne, R.; Crosse, B.; Emrich, David ; Franzen, Thomas ; Hasegawa, K.; Horsley, L.; Johnston-Hollitt, Melanie ; Jacobs, D.C.; Jordan, Chris ; Joseph, R.C.; Kaneuji, T.; Kaplan, D.L.; Kenney, David ; Kubota, K.; Line, Jack ; Lynch, Christene ; McKinley, Ben ; Mitchell, D.A.; Murray, Steven ; Pallot, D.; Pindor, B.; Rahimi, M.; Riding, J.; Sleap, G.; Steele, K.; Takahashi, K.; Tingay, Steven ; Walker, Mia ; Wayth, Randall ; Webster, R.L.; Williams, Andrew ; Wu, C.; Wyithe, J.S.B.; Yoshiura, S.; Zheng, Q. (2019)
      The compact configuration of Phase II of the Murchison Widefield Array (MWA) consists of both a redundant subarray and pseudo-random baselines, offering unique opportunities to perform sky-model and redundant interferometric ...