Extended Integration Time

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Extended Integration Time

It may be feasible to extend the effective coherent integration time by using phase-referencing of the ground telescopes, in order to calibrate out the effects of the atmosphere. If the ARISE orbit error is 10 cm, and it de-correlates over a 13-hr orbit, the effective acceleration error of tex2html_wrap_inline444 cm sectex2html_wrap_inline446 would accumulate to tex2html_wrap_inline448 (0.3 radians) in tex2html_wrap_inline450 sec. Ground-telescope phase-referencing with an on-source duty cycle of only 30% would then increase tex2html_wrap_inline370 to 800 sec, and the fringe-detection threshold might be reduced by a factor of tex2html_wrap_inline454. However, this would require changing sources on a time scale of a few seconds, which will be very difficult (or impossible) for the ground telescopes.


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