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Table 3

Comparison of the accuracy of the Nyquist sampled and oversampled methods for determining the positions and the intrinsic spectral index.

MUST
Parameter Nyquist sampling Oversampling


m 1 2 3 4 5 >5 1 2 3 4 5 >5

n 33 1 3 1 1 1 30 4 1 1 4
5 2 2 3 2 8 6 3 3 2 6
D
δ D Min 0.00045 0.084 0.00023 0.00023 0.043 0.00023 0.00023 0.00023 0.00023 0.00023 0.00023
δ D Max 1.4 0.25 1.5 0.062 0.73 0.00023 0.42 1.6 0.03 0.6 0.8
0.08 0.17 0.30 0.02 0.41 0.00023 0.05 0.28 0.01 0.20 0.07
δφ
δ φ Min 0.00062 0.0018 0.0038 0.0052 0.0035 0.052 0.0012 0.0010 0.0018 0.0024 0.0017
ΔφMax 0.7 1.6 1.6 0.2 3.5 1.6 0.4 1.7 0.8 3.1 2.2
0.04 0.65 0.25 0.08 1.3 0.72 0.04 0.22 0.05 0.70 0.60
α I
–2.0 –2.3 –1.8 –2.0 –1.5 –0.3 –1.9 –2.1 –2.0 –0.9 –0.8
σ 0.2 1.0 0.8 0.6 1.7 2.5 0.3 0.5 0.4 1.8 1.8

LOFAR
Parameter Nyquist sampling Oversampling


m 1 2 3 4 5 >5 1 2 3 4 5 >5

n 7 6 4 3 2 26 24 6 1 3 2 19
4 3 3 3 3 3 5 4 5 3 3 3
D
δ D Min 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004
δ D Max 0.6 0.6 1.1 0.3 0.7 2.9 0.4 0.1 0.0004 0.8 0.2 1.6
0.09 0.08 0.2 0.05 0.09 0.07 0.03 0.03 0.0004 0.14 0.03 0.07
δφ
δ φ Min 0.006 0.004 0.007 0.003 0.007 0.002 0.002 0.004 0.003 0.004 0.004 0.003
δ φ Max 1.3 4.1 3.7 3.8 3.9 8 0.7 2.9 0.04 3.6 3.8 8.1
0.09 0.6 0.5 0.4 0.6 1.6 0.05 0.4 0.03 0.6 0.6 1.7
α I
–2 –1.8 –1.5 –1.8 –1.7 –1.1 –2 –2 –2 –1.6 –1.8 –1.3
σ 0.12 0.3 0.6 0.3 0.6 1.1 0.07 0.15 0.09 0.7 0.25 0.8

MeerKAT
Parameter Nyquist sampling Oversampling


m 1 2 3 4 5 >5 1 2 3 4 5 >5

n 25 3 1 2 2 38 2 1 1 1
4 3 3 3 2 5 3 6 2 2
D
δ D Min 0.0004 0.0004 0.0008 0.0004 0.0004 0.0004 0.0015 0.0004 0.0008 0.0004
δ D Max 2.1 0.6 0.07 2.3 2.1 1.9 2.5 0.0004 1.1 1.1
0.12 0.12 0.03 0.31 0.21 0.11 0.63 0.0004 0.23 0.14
δφ
δ φ Min 0.001 0.002 0.009 0.007 0.007 0.001 0.004 0.007 0.008 0.002
δ φ Max 1.3 6.3 9.9 10 11 1.4 6.1 0.04 11 11
0.08 1.3 0.54 0.66 1.1 0.06 0.36 0.03 0.69 0.86
α I
–1.9 –1.1 –1.8 –1.5 –0.9 –2 –1.7 –2 –1.2 –1.1
σ 0.1 1.5 0.6 0.8 1.2 0.07 0.5 0.05 1 1.1

Notes. Here m is the number of locations estimated per detected source. n is the number of sources detected at the number of positions shown. is the mean number of TABs per source. Below we list the minimum (δDMin), maximum (δDMax) and mean () value of the total area D covered by the overlapping values of s1/ s2 and (a2 − a1), normalised to the ΩHPBWL area in deg2. The total area D represents the area that would need to be sampled in follow up, or archival, observations to be sure that the actual position of the source was observed. We also list the minimum (δφMin), maximum (δφMax) and mean () value of the total angular distances Δφ between the true and the estimated source position, normalised to the HPBWL. is the mean estimated intrinsic spectral index of all sources from group m where σ is the standard deviation from that mean.

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