JongHo Park updated #8548
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About sign flip of the phases of visibility ratios 'LR/LL', 'RL/RR', etc, in VPLOT.
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Ticket ID: 8548
URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/8548
Full Name: JongHo Park
Email: jhpark at astro.snu.ac.kr
Creator: User
Department: AIPS Data Reduction
Staff (Owner): -- Unassigned --
Type: Issue
Status: Open
Priority: Default
SLA: NRAO E2E
Template Group: Default
Created: 14 June 2016 08:21 AM
Updated: 14 June 2016 08:21 AM
Due: 16 June 2016 08:21 AM (2d 0h 0m)
Resolution Due: 22 June 2016 08:21 AM (8d 0h 0m)
Hi,
I realized that in VPLOT, the sign of the visibility phases of stokes 'LR' is inverse of those of visibility ratio 'LR/LL' even though my target is core-dominated source, i.e., the phases of 'LL' is almost zero.
I checked for other visibility ratios such as 'RL' versus 'RL/RR' and found similar results.
I attached an example showing the phase of LR and LR/LL.
Could you tell me if it is due to some errors in AIPS or I'm missing something in the calculation of complex numbers?
If there is some problems in AIPS, does it affect D-terms we measure in LPCAL? because we use visibility ratios in the complex plane to determine D-terms.
Best Regards,
Jongho Park (at Seoul National University)
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