Example 1: Using the Time Series Tool

Step 1. The VAO Time Series Tool can be found at the VAO Science Tools Page.

Step 2. In the center of the page under the heading "VAO Time Series Search" there are two text input fields. The upper field is for the object name or location (see the red-circled region), and the lower one is for a search radius in arcseconds. The default search radius is 10 arcsec, but may be modified. Beneath the text entry fields are example objects and formats.

Step 3. Enter an object name or position. Objects may be specified by object name (not case-sensitive). Positions should be in J2000 decimal RA and Dec, or J2000 sexagesimal RA and Dec (colons or spaces are acceptable as separators).

This demo uses Kepler 11 as the input object. The search engine will not recognize abbreviations for objects named by missions. For example, entering "kep 11" instead of "Kepler 11" will yield the error message "Invalid object name".

Note that once the "submit" button is clicked, the object identifier may be updated to reflect another database identification scheme. Here, Kepler-11 becomes GSC 03144-00002.

Step 4. A search results table appears beneath the text entry fields (see the table in the green box). It contains columns showing the source of the data set, the total number of holdings in that data set, the number of entries found that match the object within the search radius, and an option to display the results.

Step 5. Now try expanding the search radius. Repeat the search as before, but this time, enter a search radius of 5000 arcsec. If a non-numerical entry is made in the radius text field, the error message "Search radius parameter string is not a real number" will appear. Once the desired search radius has been entered, click "submit".

Step 6. Note that the results table now displays more matches. Clicking "display" will bring up a window showing the data table from the selected source. Click here for Column header definitions for this table. The last three columns of the data table have the column headers, "TSC", "Data", and "Periodogram".

Demonstration of the links in these last three columns is shown in the next example.

Example 2: Accessing the linked services

Step 1. Repeat the search as before, but this time, use the second example for location, entering the coordinates 88.31522 +32.61827 in the location field, and click, "submit". A results table like the following will be displayed.

Step 2. Selecting "display" will bring up the data table.

Step 3. Now select the "TSC" link in one of the rows. A window like the following will appear from the Harvard Time Series Center. Further services from this site may be accessed by the links at the top of the page.

Step 4. Returning to the data table, the user may also select the "data" link. Doing so will open an ASCII text file with tab delimited data.

Step 5. Finally, after returning to the data table again, the user may select the "Periodogram" link. Now a window opens for the NASA Exoplanet Archive's periodogram application. A table diplaying the available light curves appears.

Step 6. Click on the desired light curve, and an interactive light curve plot page will appear as below.

Known Issues

1. In this release of the VAO Time Series Tool, there is a problem the Periodogram has with the CACR lightcurves. It doesn't recognize the column names, so it won't generate a periodogram initially. However, after getting the error message, the user can select new columns (ObsTime and Mag) and the service will work.

2. This service has been found to be incompatible with Internet Explorer version 9, Opera, and old versions of Firefox (prior to version 8). It is recommended that the user employ Firefox Version 9, or current versions of Safari or Chrome to use this service.