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Guidance on HST Obs Requests

msheald's picture
msheald
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Joined: 2010-10-02

Hello! Given my lattitude of -23, I am fairly well situated to observations of DT OCT and GW LIB. However, being relatively new, I am unsure of what is requested. Are single observations each night needed or time series? Which filters and, if a time series, how often would be useful? I have an 8in Meade SCT Classic with SBIC ST-402 with BVIC filters. Thank you and best regards.

 

Mike

observation guidance
HQA's picture
HQA
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Joined: 2010-05-10

Hi Mike,

HST is primarily concerned about whether the targets are in outburst.  Towards that end, they want to know, within 24hrs of the scheduled observation, whether they need to worry.  The researchers also like to have monitoring observations even earlier, days or weeks, so that they understand the state the CV system is in.  Is it recovering from a recent outburst, for example?

Therefore, time series is not required.  If you can reach the star and get an actual measurement with a standard filter, that is best, and V-band is the most common filter.  If an exposure of 10 minutes or so still doesn't result in a detection, then an unfiltered observation is fine - the main point is that a detection is more valuable than an upper limit.  However, all observations are accepted.

As for cadence: you are at a great longitude, so are very complementary to most of the observers.  I'd probably try to do three observations: beginning of night, midnight, dawn, if possible just to both give the best time span as well as demonstrating that any single measurement wasn't in error.  When you are within that 24hr window, it is more important to report your observation than to take extra time to get the most precise value - you can always go back and replace a crude estimate with a better one later.

Arne

Hi Mike, Arne already
BorisGaensicke's picture
BorisGaensicke
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Joined: 2013-03-19

Hi Mike,


Arne already replied, but let me just add a few more lines: in the run-up to the HST observations (scheduled for May 30), it will be very helpful to get a few V-band measurements per night, i.e. no long time series, but one or two measurements every couple of hours. It is extremely unlikely that this star will show any activity, but we still need to prove that this is the case.

Thanks for your help & best wishes,


Boris

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