Searching VSX by magnitude of variation

Technology
1

VSX is a great resource, but the influx of Gaia and other survey data makes finding targets harder. VSX allows you to filter by mean magnitude range. Great for searching targets in your instruments range, but my equipment is not useful for targets whose magnitude change is 0.04 mag in W1 or even R. Is there a way to filter on delta mag?

Otherwise, I will need of write a script to strip targets whose delta magnitudes below my equipment precision.

-JH

-JH

2

One can use, if necessary, both filters - Mag at MAX and Mag at MIN. It helps to define range.

3

Hi John,

We are aware of that limitation, and in the future version of VSX, we will include amplitudes in a separate field in order to make searches like that possible.
It will take some months before we can make it available though.

I did not understand why you specifically mentioned the W1 and R passbands in the context of this issue. Could you explain?

Thanks and cheers,
Sebastian

1 Like
4

Thanks for your reply. I am working on a python app that uses the Php GET interface to VSX that will take a delta Mag search criteria and output a CSV for my local DB or sorting with a spread sheet. Once Delta mag is a filter critera my queries of VSX will take less network bandwith. I haven’t checked, but if VSX can be accessed with a cone search from TopCAT I won’t need to generate the App.

I only mention those filters as I have ocassionally overlooked filter references when setting up my obsserving scripts and scaled my exposures based on a V default and wasted a session. That is on me and I now check Gaia or APASS to estimate effective temperature and exposure times for my scopes.

Best regards,
-JH