Multimission Archive at STScI (MAST)

From RP
Revision as of 07:11, 21 November 2008 by Wikisysop (Talk | contribs)

Jump to: navigation, search

Description

The Multimission Archive at STScI (MAST) supports a variety of astronomical data archives, with a primary focus on scientifically related data sets in the optical, ultraviolet, and near-infrared parts of the spectrum. See http://archive.stsci.edu/missions.html for a full list of the mission, survey, and catalog data distributed by MAST. MAST is a component of NASA's distributed Space Science Data Services (SSDS).

Overview

Mission Statement: The staff of the archive branch and the multi-mission archive at STScI provides:

  • world-wide technical and scientific leadership in archive system design
  • secure storage and reliable retrieval services for data from HST and all MAST-supported missions
  • user-friendly and scientifically useful search and cross-correlation tools
  • development and support for inter-archive communication and data transfer standards
  • accurate and useful mission archive documentation
  • helpful user support services with a 1 business day response time

MAST archives a variety of spectral and image data with a range of data characteristics. To see a complete list of missions with data archived with MAST, click on the Mission Link in the top menu bar. MAST also provides a large suite of searches. In addition to customized searches for each mission, MAST provides several cross-mission searches.

MAST also archives sets of High-Level Science Products (HLSP). Users may search for High-Level Science Products by target or coordinates by using the HLSP search page. MAST actively solicits submission of High-Level Science Products related to our missions and we provide guidelines contributing them to MAST.

The MAST Users Group provides essential user perspectives on archive operations and development, including suggesting priorities for short and long term operational and scientific enhancements to the archive.

Although there is no cost involved in retrieving data from MAST, researchers are requested to include an acknowledgement (as shown in the MAST Data Use Policy) in publications that make use of MAST.

Mission and Target Name Search Window

The website form allows one to

  • perform a quick search by target name or coordinates for a specified set of data types (default is all). (Note: this mode currently excludes x-ray and radio missions) , or
  • list and briefly describe the available MAST missions for a specified set of data types (default is all).

Clicking the "search" button without any selection criteria will return a list of all the existing MAST data sets. The information below describes the various search options.

Note: if you already know which data set(s) you are interested in, (i.e., which mission or survey), you may instead

  • click the "Data Search" link to display a list of links to mission-specific search scripts, or
  • click on the mission names shown on the top MAST page to go to the mission home pages (a similiar list is displayed by clicking the "Missions" link at the top of the page).

The interface is a simple form with the following fields:

  • Enter Target name (or Coordinates):
  • Resolver: *SIMBAD *NED *Don't Resolve
  • and/or Band/Data Type(s):
  • Image (from Extreme UV to Radio)
  • Spectra (from Extreme UV to near IR)
  • Other (from Far UV to near IR)

High Level Science Products

High-Level Science Products (HLSP) are community contributed, fully processed (reduced, co-added, cosmic-ray cleaned etc.) images and spectra that are ready for scientific analysis. HLSP also include files such as object catalogs, spectral atlases, and README files describing a given set of data.

Search the HLSP to find objects of interest by product, object type, and/or wavelength. Select more than one item in each list by using the shift and the control keys. Click on the "search" button for a list of the products for that project. The title of the project is a link to more information about the project. You may search for specific targets by using the HLSP search page. You may also be interested in more information about download options. MAST encourages the submission of HLSP based on data from its missions. Please consult the Guidelines for Contributing HLSP for more information.

Spectral Data Coplot Utility

User can enter up to 15 data set names (e.g., SWP16877,O45P021B0,...) to coplot spectra from STIS, IUE, EUVE, HUT, BEFS, TUES, FOS, GHRS, or WUPPE. Scale factors and wavelength range can be specified either here or on the displayed plot page. (Caution: the averaging feature checks that the input spectra have the same total number of points and averages them bin by bin. It will cheerfully 'average' spectra with different wavelength ranges or resolution, producing meaningless output.)

NED Search Form

Use the NED Search form to search the NED Catalog by object name, position, object category, etc. and optionally, cross correlate results with MAST missions.

Scrapbook Search Form

Search the MAST catalog of representative spectra or images for an astronomical object. User can enter a target name or coordinates. Only fixed targets (i.e., no solar system objects) are available. A table of results will be displayed along with thumbnails of images or spectra.

Dataset Locations

Search MAST for a target or mission: http://archive.stsci.edu/

Cross-correlation search form: http://archive.stsci.edu/xcorr.php

High Level Science Products (HLSP): http://archive.stsci.edu/hlsp/index.html

HLSP Search Form: http://archive.stsci.edu/hlsp/search.php

Scrapbook Search Form: http://archive.stsci.edu/scrapbook.php

NED Search Form: http://archive.stsci.edu/ned.php

Spectral Data Co-plot Utility: http://archive.stsci.edu/mast_coplot.html

Definitions

Target Name (or coordinates) - Entering either a target name (to be resolved by SIMBAD (default), NED, or left unresolved), or J2000 coordinates (RA and DEC separated by a comma or Dec sign) will start a cross-correlation search for available data sets within MAST. Multiple target names can also be specified with comma delimiters, but only one set of coordinates can be specified. Coordinates can be either in decimal degrees or sexigesimal notation with either blanks or colons separating values. Valid coordinates include: 

        8:32:40.3,+28:49:43
        10.681,41.269
        10 30 5 -28 30 0

If band/data types are selected, the search will be restricted to the appropriate MAST missions. (Note: target searches currently exclude data sets from x-ray and radio missions).

Currently all missions use 3.0 arcminutes as the default search radius except for vlafirst (20 arcmin.) and galex (6 arcmin.).

Data Type(s) - Archived data sets have been classified according to the type of data (i.e., spectral, image or other) and wavelength coverage. Selecting various data types and wavelength ranges and then clicking "Search", will return a list containing both a summary of each missions data holdings and a link to the mission home pages. If a particular target is also specified, the results page will list the actual data sets available from each of the selected missions (Note: target searches currently exclude data sets from x-ray and radio missions).


The wavelength ranges and data types used in the table are as defined below:

X-ray -That portion of the electromagnetic spectrum having wavelengths from ~0.1 to ~124 Å (i.e., ~124 kev to ~100 eV). (Note searches on target name exclude x-ray mission data.)

Extreme UV - The extreme ultraviolet wavelength range is defined as ~70 to 912 Å.

Far-UV - The spectral region from 912 to 2000 Å.

Near-UV - The spectral region from 2000 to 3400 Å.

Optical - The spectral region from 3400 to ~7500 Å.

Near-IR - The spectral region from ~7500 Å to ~30 µ.

Radio - That portion of the electromagnetic spectrum having wavelengths greater than ~10 cm. (Note searches on target name exclude radio mission data.)

Images - Image data refers to digital images obtained within various bandpasses and with various spatial resolutions. (Note: images of spectra are not included in this category.)

Spectra - This category refers to spectroscopic data containing calibrated or uncalibrated fluxes as a function of wavelength.

Other - Data sets listed in the "Other" category include polarimetric, photometric, and astrometric data.

Associated Data Analysis Software

Some of the data analysis software packages used for the MAST archived data are:


Useful data visualization software includes:

  • Aladin Sky Atlas to search, retrieve and visualize digitized astronomical images and catalog entries
  • Specview for 1-d spectral visualization and analysis
  • Starview, an astronomical database browser and research analysis tool

Information on these and other available astronomical data reduction and analysis software packages may be found at the Astronomical Software and Documentation Service.

Retrieved from "http://www.researchpipeline.com/mediawiki/index.php?title=Multimission_Archive_at_STScI_(MAST)&oldid=59"