EVLA Memo #165 The Impact of the New Thermal Gap Receiver Assembly on the Sensitivity of the EVLA at L-Band (1–2 GHz)
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چکیده
We present sensitivity measurements of the EVLA at L-band between 1 and 2 GHz to assess the impact of the receivers with the new thermal gap assembly. Our on-the-sky test results are consistent with lab measurements, and show that the sensitivity improves by an average value of ∼7% in the frequency range 1–1.55 GHz, and degrades by an average value of ∼3% in the frequency range 1.55–2 GHz. The sensitivity improvement at the lower half of L-band will particularly be valuable for the study of various spectral line transitions that can be observed in this frequency range.
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EVLA Memo #188 The Impact of the New Thermal Gap Receiver Assembly on the Sensitivity of the EVLA at C-Band (4–8GHz)
Sensitivity measurements of the EVLA at C-band (4–8GHz) are presented to assess the impact of the receivers with the new thermal gap assembly. The on-the-sky test results are consistent with lab measurements, and show sensitivity improvement across the full frequency range of the C-band receiver. The overall improvement in the sensitivity is ∼9.4%. In the frequency range 4–6GHz, the sensitivity...
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