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WFC3 Persistance Help
This page describes how to use the HST WFC3 Persistance search form and describes the individual fields in that form.
Use the HST WFC3 Persistance Search form to search for WFC3 IR observations that have a correction for
- Target Name
- The name of the astronomical object you want to search for.
- The name resolver you want to use, if you want to get an object's coordinates. To resolve an object's name into its coordinates, enter the object name in the Object Name field, select either NED or SIMBAD for the resolver. When you click on the "Search" button, the script will get the coordinates before doing the search. A message will appear at the top of the results page showing you what coordinates were found for the object (or an error message if the name resolver didn't work for some reason).
You do not have to use a resolver. One of the choices in the resolver selection menu is Do not resolve. Use this when you would like to search the object name field.
We recommend that you use object-name resolution to find observations of fixed targets in the database. This is the most reliable way to look up observations, because the observer could have given the observation any name at all (for example, NGC1976 instead of M42, or PARALLEL-FIELD). However, if you do know the name of the object, you can select HST Target Name, in which case, the object name will not be resolved into coordinates, but will be used as a search qualification in the database.
The SIMBAD and NED object name resolvers can only resolve the names of fixed astronomical object; they cannot compute the positions of moving objects (planets, comets, etc.).
- The Right Ascension and Declination around which you want to search. A number of formats are accepted for the RA and Dec. Here are some examples:
Decimal Degrees 185.63325 29.8959861111111 Hours, minutes and Seconds 12 22 31.98 29 53 45.55 12h22m31.98s 29d53m45.55s 12:22:31.98 +29:53:45.55 12h22'31.98" 29d53'45.55" 12h 22m 31.98s 29d 53m 45.55s 12h 22' 31.98" 29d 53' 45.55" 12h 22' 31.98" -29d 53' 45.55" 12h22'31".98 -29d53'45".55 12h22m31s.98 -29o53m45s.55 12h 22' 31".98 -29d 53' 45".55 Hours/Degrees and Minutes (no seconds) 12 22 29 53 12h22m +29d53m 12h22m 29d53m 12:22m 29:53m 12h22' 29d53' 12h 22m 29d 53m 12h 22' 29d 53' 12h 22' -29d 53' The RA may be given in decimal degrees by indicating a D or d after the degrees: 12d 22m 29d 53mSpacing is not important, as long as the value is unambiguous, and that you can delimit the hours/degrees, minutes, and (optional) seconds with letters, colons, spaces, or any character that's not a digit or a decimal point.Note also that seconds of the form 31".98 or 31s.98 are accepted. This should make it easy to cut and paste values into these fields from electronic publications.
- How far around the search position you would like to search, in arcminutes.
We compute the angular separation between each result dataset and the search center. (The results will be sorted on the angular separation by default.)
One result is that you can do fancy stuff like searching for all observations between 2 and 8 arcminutes from the center of a galaxy (just give 2 .. 8 for the radius).
- The date of the observation. More specifically, the date and time, in GMT, on which the exposure was started. When specifying this date, you need to include a date and an optional time. The date can have any of the following formats (the month name can be spelled out or abbreviated to three letters; case is not significant):
Jul 15 1994 Jul 1994 15 15 Jul 1994 1994 Jul 15 1994 15 Jul 7/15/1994 7-15-1994 7.15.1994If the day is omitted, the first day of the month is assumed. This means that a specification like "July 1994" will look for observations done on July 1 1994 00:00:00, not for observations done during July 1994. Note also that when entering a date with the month in numerical format, the American ordeing is used; i.e., the first number is the month.If a time is omitted, then midnight (00:00:00) is assumed. Otherwise, you can specify a time in any of these formats:
14:30 14:30:20 14:30:20:999 14:30:20.9 4am 4 PM 04:30:20 AMTo search for observations before a given date, use <, and for observations after a given date, use >. For example,> Jul 15 1994 < Jul 15 1994You can use the .. operator to search on a range of dates:Jul 1 1994 .. Aug 1 1995This operator is inclusive on the first date and exclusive on the second.Finally, you can search on a list of dates or date ranges. For example,
Jul 1 1994 .. Jul 3 1994, Dec 1 1995 .. Dec 6 1995will search for observations done within either one of these date ranges.- The commanded exposure time in seconds. You can use operators or ranges in this field; for example,
< 100 > 1000.0 100 .. 1000
You can exclude a range of exposures using a comma:< 100, > 1000
- The last name of the principal investigator of the observation. We sometimes refer to this person as the "observer".
- The HST proposal number under which the observation was executed. This can be a numeric ID or a comma-separated list of numeric IDs. Any characters other than digits, commas, and spaces will cause an error message to be displayed. For example, instead of searching for GO-111738, simply specify 11738. Or to search for observations from either proposal 11929 or proposal 11738, specify 11929, 11738.
- The dataset name is the unique identifier for an HST observation. (For NICMOS and STIS, it can also represent an association of exposures.) This value can be wildcarded using a *. When you specify a dataset name, any instrument or wavelength specification will be ignored.
- Enter HST aperture(s); These examples
IR-FIX IR-UVIS-CENTER IRSUB256 IRSUB512-FIX GRISM128 IR-UVIS-FIX G141-REF GRISM512 GRISM1024 GRISM256 IRSUB128-FIX IR IRSUB64-FIX IRSUB512 IRSUB64 IRSUB128 IRSUB256-FIX G102-REFare a subset of the complete list.- Enter HST filter name(s); for example
F164NorF110W, F160Ware a subset of the complete list.- The observation set within the program. This is usually the same as the visit number, though in a small number of cases it will be different. The obset ID is used as the fourth and fifth letters of a dataset name. You can enter a comma separated list here. If necessary, obset IDs will be padded with leading zeroes to two characters.
If it is visit 01 enter the 01 not just a 1.
- Select the release date for the data, in GMT. See the observation date for the entry format. HST data has a nominal proprietary period of one year (though in special cases, this may be shortened or extended). The Release Date field gives the end of the dataset's proprietary period.
- This is the date on which a dataset was processed by the team creating the persistance files.
- This is the status of the persistance processing.
- Percentage of pixels which external persistence is estimated to be greater than 0.1 e/s
- Percentage of pixels which external persistence is estimated to be greater than 0.03 e/s
- Percentage of pixels which external persistence is estimated to be greater than 0.01 e/s
- Percentage of pixels which total persistence is estimated to be greater than 0.1 e/s
- Percentage of pixels which total persistence is estimated to be greater than 0.03 e/s
- Percentage of pixels which total persistence is estimated to be greater than 0.01 e/s
- You may choose the columns to be displayed in the output. A set of columns that are commonly requested has been chosen as a default.
The default set of columns is:
Dataset ASN ID Proposal ID Visit Aper Target RA (J2000) Dec (J2000) Exp Time Filter PI Last Name Release Date Status EXT1 EXT2 EXT3 TOT1 TOT2 TOT3 ang_sep (')You remove output columns by highlighting the column to be removed and then clicking on the remove button to the right of the list of chosen output columns.
You may determine the order of column placement by highlighting a column and then clicking on the up or down buttons to the right of the list of chosen output columns.
You may add a column to the list of chosen columns. Select the desired column on the pull down menu beneath the list of chosen output columns. Then click on the add button. The column will be added to the bottom of the output column list.
- Choose how you want the output rows sorted. You can select up to three fields to sort on. the rows will be sorted in the order of the first sort field; if two rows have the same sort field, they will be sorted in order of the second sort field, and so on.
For each field, you can select that the rows be sorted in reverse order on that field by selecting the reverse checkbox. For example, you can sort the rows with the most recent observations first by selecting Observation Date for the first sort field and selecting the reverse checkbox next to it.
- Some queries will be capable of returning thousands of rows or more. Such large search results tend to use up memory on both the client and server sides, and aren't usually useful. By default, we limit the number of rows displayed to 100 rows, but you can increase (or decrease) this limit as needed.
- Select this checkbox if you want to see the SQL query that the HST Search engine constructs from your query qualifications. The query will be shown at the end of the search results.
SQL (Standard Query Language, pronounced either "ess cue ell" or "sequel") is a language used by most relational database systems for retrieving information from database tables. The HST Search Page takes your search specifications and converts them to an SQL query to run on our database. Viewing the generated query is often useful for debugging, and may also be useful for SQL-literate users who want to see what logic was used in the query. (In fact, this may be useful for most people, since SQL is pretty easy to understand.)
- Select this checkbox if you want to have a set of distinct rows displayed. This is useful if you would like to see a distinct list of objects with certain criteria e.g. all the objects with similar target description. To make this function useful, you should not select column names such as Dataset Name, Mark or Observation Date in as output columns as all output is considered when making rows distinct.
- You may choose one of three display options: HTML Form, a comma separated list, and Excel spreadsheet
- The name resolver you want to use, if you want to get an object's coordinates. To resolve an object's name into its coordinates, enter the object name in the Object Name field, select either NED or SIMBAD for the resolver. When you click on the "Search" button, the script will get the coordinates before doing the search. A message will appear at the top of the results page showing you what coordinates were found for the object (or an error message if the name resolver didn't work for some reason).
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