GRBOX : Gamma-Ray Burst Online Index

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One objective of this website is to be as simple and intuitive as possible, and the most effective way to become familiar with its use is to simply experiment. Nevertheless, certain features are not obvious or may require additional explanation, so a brief 'manual' is provided below.

General Information

Note that only a small amount of the information stored in the database is displayed by default. To access most of the sorting and display options, use the primary table controls - scroll all the way down to the bottom of the page access them.

Almost all text has mouseover information and will bring up the reference when clicked. In addition to providing proper attribution, this can be useful in order to to double-check that the information was entered correctly.

Available Information

The user may elect to display any or all of the following categories of information as columns.

• GRB index - A six-digit number indicating when the GRB occurred, followed in some cases by a letter if multiple GRBs occurred on the same day. Mousing over this field will give the triggering satellite and (for some bursts) the trigger number. Click to go to the triggering satellite's burst information page.
• T90 - The duration of the burst. T90 is presented if available; else the more loosely defined 'duration' quoted in the GCNs is given. This is always in seconds. Mouse over for the band in keV. Loosely, red indicates short bursts, blue 'normal' long bursts, and green intermediate-duration bursts. Note that some short bursts in the Swift era actually have long T90s due to extended emission, so use caution in making strong cuts on this category.
• Epeak - The peak photon energy in keV. The color correspondsd to the rough range of T90: red indicates <50 keV (X-Ray Flash); green indicates 50-100 keV (X-ray rich GRB), white indicates a 'typical' GRB with 100-1000 keV, and light purple indicates an unusually hard GRB (>1000 keV). Grey indicates only a limit is available that leaves its categorization ambiguous.
• Comments - One-line commentary on each burst pointing out any distinguishing features. Many bursts lack distinguishing features and it is a struggle to provide a brief summary. Comments may reflect other biases and limitations of the students who compiled them (Daniel Perley is a graduate student working in observational followup of GRBs; Yvonne Kemper compiled information on pre-2005 bursts as a sophomore undergraduate.) If you feel that certain interesting aspects of a burst are not reflected in the commentary, please notify Daniel!
• RA / Dec / Err - Best available position and uncertainty. Both the RA and Dec fields are color-coded by the type of position: Optical, radio, and IR positions (generally the most accurate) are white; X-ray positions are light grey; Gamma-ray positions are a darker grey, and IPN positions are very dark grey. Mouse over for the source wavelength and/or instrument and, if the error is not displayed explicitly, the error. You can choose whether the position is displayed as sexagesimal or decimal format, as well as choose whether to use positions from Butler 2007, at the bottom of the page. For optical positions with no reported uncertainty, a conservative 3 arcseconds is assumed for sorting and filtering purposes.
• b - Galactic latitude. Positions close to the plane are colorized to note that the extinction is likely to be significant.
• z - Redshift. Green indicates an emission-line or host galaxy redshift, while red indicates an absorption redshift. Occasionally, redshifts are disputed. We give here what appears to be the most likely redshift, but note that it is sometimes possible for these to be in error. Some redshifts are from our soon-to-be-released Keck survey of GRB hosts and are not yet in published literature.
• Afterglow (X/O/R) - Currently, this is just a direct mirror of Jochen Greiner's table with no edits or changes. This table has a few mistakes and does not report most non-detections and a re-implementation is planned. Clicking on a link will bring up either an X-ray plot or list of X-ray circulars; an optical plot from GRBlog; or a list of radio circulars.
• Host mag. - Host magnitude, taken from a large number of heterogeneous sources. When no host is reported, instead the faintest afterglow detection or limit from the GCNs is reported, operating under the assumption that the host galaxy must be fainter than that or it would be detected. This is not always the case, and we encourage you to help with pointing out any errors. Magnitudes from the Keck host survey are not yet reported.

External Resource Links

The GRBOX table can serve as a useful interface for other websites, avoiding the chore of re-entering positional or other information. You may opt to display a large number of external links for each burst:

• GCNs - Link to the GCN circulars page for each burst day. Note that the GCN pages put multiple bursts per day all on the same page.
• GRBlog - Link to the GRBlog summary page on each burst. This can be an extremely useful way to gather information from many different wavelengths and view all the circulars on a burst.
• ADS - This displays a numerical link that executes an ADS search for published articles with that burst name in the title. A script executes this search automatically for each burst twice per week; the number displayed indicates the number of these articles that exist. No number means no articles (the case, for example, for most recent bursts.)

In addition, you can choose to display a finding chart from several different potential sources:

• DSS
• USNO Image and Catalogue Archive
• 2-Micron All Sky Survey
• SDSS

The SDSS link appears only if the GRB is "approximately" in DR5. The estimation of this is very artificial and misses some SDSS fields and includes some bursts that are not in SDSS. This will be done more exactly in the future.

Some other links are also available:

• NVO DataScope - This is a service from the NVO that searches numerous catalogs for sources near the burst position.
• Airmass table - By selecting an observatory site and observation date, links to an airmass / elevation / parallactic angle table will appear for each burst. In addition, the link will be highlighted light or dark based on whether or not approximately (using a very simplistic calculation) the burst is easily observable on that date from that site.

Sorting

All of the numerical fields also allow you to sort by that column. You can either select a sort radio button or simply click on the title at the top of the column to sort.

To change the sort direction, check or uncheck the Reverse box. Or, clicking the column title a second time after that column is already sorted reverses the sort direction.

Unknown or absent values are generally treated as zero for the purpose of sorting.

Note that the GRB column actually sorts by UT, so bursts are not always ordered A, B, C the way you might expect.

Filtering

Always displaying all bursts is very unwieldly. By default, the site only brings up bursts for 2007, allowing you to select different years using the shortcut quick-filter links at top. However, you can choose different filter criteria using any numerical field.

To do this, enter a range in the Start and End boxes below 'Data Options' at the bottom of the page. You can enter only a Start or only an End and it will behave the way you expect, using only a maximum or only a minimum, respectively.

Mouse over the title for more information on filtering by specific fields, as they generally assume values in specific units. Some fields allow the following:

• To include only bursts for which the field is known (i.e., known redshift, known E_peak), enter a minimum (Start value) of zero. To include only bursts for which the field is unknown (i.e. unknown redshift), enter a maximum (End) of zero.
• If you want to exclude a given region - such as, for example, exclude bursts close to the Galactic plane, swap the Start and End values (e.g., enter a Start of 10 and an End of -10.) In the case of RA, doing this will also make the list wrap through zero when sorting by this column.

Text Output

You can export much of the data in the table to other formats. At the bottom of the table is a series of links that, when clicked, will print the displayed table in the specified format. (Note that if you have changed options in the fields since the table was displayed those will not be reflected unless you Resubmit Query first.

The options in which to save are:

• XML - The original form used to archive the data; click this to access the raw XML on the bursts displayed. Unfortunately, information not in the original XML (such as positions from Butler 2007) will not in general be reflected here, either, until our server's PHP is updated to the most modern version.
• KML - KML is used to display figures in Google Earth. Use this to save a file with all relevant GRB positions and use Sky in Google Earth to bring up images of the fields. Unfortunately circles do not yet exist in KML so only a point is displayed. IPN error boxes are displayed accurately for bursts since 2001, but not older bursts.
• Starlist - Some observatories use a specific format for inputing sources into their system to allow the Telescope Operator to quickly access the coordinates to their field. This will save the bursts in that format.
• Text file - Fixed-width-column text file.

Non-information columns (links), as well as some information columns (such as Greiner X/O/R) will not display in text files.

Tips

• For the redshift, positional error, and host magnitude columns, use a minimum of '0' to hide unknown results (for example, only sources with known redshift) or a maximum of '0' to see only unknown results.
• You can filter (and sort) by hidden columns by using the radio buttons.
• To make the RA column wrap about a value other than zero if sorting by RA, make the maximum value less than the minimum value, or just enter a minimum value with no maximum.
• If you want to save a query for later re-use, copy and save the URL from the address bar (or just bookmark the page) and you can return to it later without having to re-enter anything. (If the link size is unwieldy, use tinyurl.com.) Or, just use 'Save As...' to save the page as an .html file to your computer if you need to access it offline. If you do this, also save the style file and put it in the same directory, or else the formatting will not display.