TY - UNPB
T1 - MeerKLASS L-band deep-field intensity maps
T2 - entering the HI dominated regime
AU - Collaboration, MeerKLASS
AU - Barberi-Squarotti, Matilde
AU - Bernal, José L.
AU - Bull, Philip
AU - Camera, Stefano
AU - Carucci, Isabella P.
AU - Chen, Zhaoting
AU - Cunnington, Steven
AU - Engelbrecht, Brandon N.
AU - Fonseca, José
AU - Grainge, Keith
AU - Irfan, Melis O.
AU - Li, Yichao
AU - Mazumder, Aishrila
AU - Paul, Sourabh
AU - Pourtsidou, Alkistis
AU - Santos, Mario G.
AU - Spinelli, Marta
AU - Wang, Jingying
AU - Witzemann, Amadeus
AU - Wolz, Laura
N1 - 29 pages, 27 figures. See Fig.14 and 15 for auto-HI and HI-galaxy cross power spectra. Fig 19 and 20 for stacking detections. Submitted to MNRAS
PY - 2024/7/31
Y1 - 2024/7/31
N2 - We present results from MeerKAT single-dish HI intensity maps, the final observations to be performed in L-band in the MeerKAT Large Area Synoptic Survey (MeerKLASS) campaign. The observations represent the deepest single-dish HI intensity maps to date, produced from 41 repeated scans over $236\,{\rm deg}^2$, providing 62 hours of observational data for each of the 64 dishes before flagging. By introducing an iterative self-calibration process, the estimated thermal noise of the reconstructed maps is limited to ${\sim}\,1.21\,$mK ($1.2\,\times$ the theoretical noise level). This thermal noise will be sub-dominant relative to the HI fluctuations on large scales ($k\,{\lesssim}\,0.15\,h\,\text{Mpc}^{-1}$), which demands upgrades to power spectrum analysis techniques, particularly for covariance estimation. In this work, we present the improved MeerKLASS analysis pipeline, validating it on both a suite of mock simulations and a small sample of overlapping spectroscopic galaxies from the Galaxy And Mass Assembly (GAMA) survey. Despite only overlapping with ${\sim}\,25\%$ of the MeerKLASS deep field, and a conservative approach to covariance estimation, we still obtain a ${>}\,4\,\sigma$ detection of the cross-power spectrum between the intensity maps and the 2269 galaxies at the narrow redshift range $0.39\,{
AB - We present results from MeerKAT single-dish HI intensity maps, the final observations to be performed in L-band in the MeerKAT Large Area Synoptic Survey (MeerKLASS) campaign. The observations represent the deepest single-dish HI intensity maps to date, produced from 41 repeated scans over $236\,{\rm deg}^2$, providing 62 hours of observational data for each of the 64 dishes before flagging. By introducing an iterative self-calibration process, the estimated thermal noise of the reconstructed maps is limited to ${\sim}\,1.21\,$mK ($1.2\,\times$ the theoretical noise level). This thermal noise will be sub-dominant relative to the HI fluctuations on large scales ($k\,{\lesssim}\,0.15\,h\,\text{Mpc}^{-1}$), which demands upgrades to power spectrum analysis techniques, particularly for covariance estimation. In this work, we present the improved MeerKLASS analysis pipeline, validating it on both a suite of mock simulations and a small sample of overlapping spectroscopic galaxies from the Galaxy And Mass Assembly (GAMA) survey. Despite only overlapping with ${\sim}\,25\%$ of the MeerKLASS deep field, and a conservative approach to covariance estimation, we still obtain a ${>}\,4\,\sigma$ detection of the cross-power spectrum between the intensity maps and the 2269 galaxies at the narrow redshift range $0.39\,{
KW - astro-ph.CO
KW - astro-ph.GA
M3 - Preprint
BT - MeerKLASS L-band deep-field intensity maps
ER -