Instructions for source matching

Updated Source Matching

1. Open up the table from Gregorio's paper. File:Gregorio 20120514.txt in one webpage. You may need the paper itself later.

2. Open up another webpage with the Gator Catalog List

3. Open up a third window to show our google docs spreadsheet Gregorio Source Matching.

4. In Gator, choose 2MASS (Two Micron All-Sky Survey), the second choice. Then click the Select button by the title IRSA CATALOGS.

5. On the next page, choose 2MASS All-Sky Point Source Catalog (PSC) and then click the Select button by the title 2MASS All-Sky Release Database. The query page that comes up is the one we will be using over and over.

6. Find the Gregorio sources you are responsible for in our spreadsheet. You may want to sort the data by column B to find your sources easily. To do this, click on column B, go up to the Data menu and choose sort. Or just use the arrow button on the cell label for column B and choose sort. We only care about the sources that are marked with * in Gregorio. The others are not in our BRCs.

7. Follow the next steps for one source at a time. Enter your data in our spreadsheet. You are going to have to enter one cell's worth of data at a time in the google doc, whereas you can highlight both ra and dec at once and paste it into the query form webpage. You will notice that Gregorio did some matching to 2MASS, but it is not updated. So we need to do each one in the area we are interested in.

If you get stuck, especially when it is hard to tell which source is the one you want, that's OK. We are all learning and we have to help each other. On that note, if these instructions are confusing, let me know! Just go one step at a time.

Step by step instructions once you have the windows open

A. In Gregorio's table, copy the RA (hh mm ss - hours, min, sec) and Dec (deg, arcmin, arc sec) for your object.

B. In the query webpage, paste the ra and dec in the Coordinate or Object Name box

C. Under method, leave Cone checked and change the Radius to 5 (5 arc sec)

D. Click the Run Query button.

E. Two possible outcomes at this step. Look at the plot.

The Red triangle and free circle matchup. The red mark is where the coordinates you put in are located. The green circle is a source that 2MASS found at or close to your location. If there are sources found, they will show up in rows listed under the plot. Look at the sources returned. Is there just one within 5-10 arcsec? that's probably your match; go on to the next source (steps H - K below).

There is more than one source indicated because your red mark is not one particular source. You have to ask yourself - is there just one BRIGHT one within 5-10 arcsec? Is there another source from that same paper within 5-10 arcsec? If the answer to either of those questions is yes, go on to steps F - G, then H-K.

F. Go get the images in another window from the Finder Chart. Scroll down to find the 2MASS images. Compare the images (if provided) from the original papers. Compare the finder chart image to the images provided in the papers and/or the query results. Identify which object is the one(s) in the paper. You are going to have to choose which object you think is best. Make a note in the spreadsheet.

G. With that information, then go back to your PSC (point source catalog - the query webpage), and then use the 2MASS point source catalog to find the actual high-precision coordinates of that specific dot you have identified in the images as the match to the literature object.

H. When you have identified the source, scroll through the listed rows below the plot and find the designation. Copy this and paste it into the spreadsheet. This is 2MASS's name for your object.

I. Do the same thing for ra and dec from the row. Both of these will be in decimal deg, not hours or deg. Paste both into the spreadsheet.

J. Make any comments you feel necessary. If you had a hard time deciding between 2MASS sources; No sources showing up; etc.

K. To do another source, scroll up to the top and click the Return to query page button. Copy and paste another set of coordinates. You will have to change the radius again.