Introduction

This Webpage hosts and collects observational data of protostars. Eventually this should include broad band photometry, broad band mapping of the envelopes, line observations of the envelopes, polarimetry, and observations of the associated outflows. This data will be used in order to study the properties of these objects on a statistical basis.

As a first step we provide here the broad band photometry for 200 candidate Class0 sources. A tool will be added that allows determination of the bolometric temperature and luminosity depending on the data one wants to use. In the future users will have the possibility of updating the database themselves by a web interface (after registering) or by email (df @ star.kent.ac.uk), in order to allow an as fast as possible growth in the available data. We are defining at the moment the possible content, layout, and timeline for this database. Hence, if you have suggestions, corrections, remarks, etc., please do not hesitate to email the webmaster of this page (df @ star.kent.ac.uk).

Data types

• PS ID: This is an internally generated unique identifier based on the object's coordinates.
  PSxxxxxx.xx+/-xxxxxx.x. As this identifier is unique, no two objects can have the same coordinates.
  
  
• Coords: Coordinates are J2000 taken from Simbad listing of "Simbad ID" object.
  
  
• Primary name: Main (usually most common) designation. Alternative designations, as listed by Simbad, are given under "Other names".
  
  
• Simbad ID: Primary Simbad name used to identify object and allow linking to Simbad entry from webpage:
  http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=???
  
  

User comments

Notes/comments can be added by users to each object using the "User comments" box. These are saved as plain-text within the database and cannot be deleted once added. Comments are automaticall timestamped and user initials are required.

Spectral Energy Distribution Plot

Available broadband photometric data is listed in an interactive table, consisting of wavelength (microns), Flux (Jy), Error (Jy), photometric aperture (arcsecs), Flag (f = flux, u = upper-limit) and originating reference.
By default, all data-points are plotted in the adjacent SED plot. Flux error bars are shown in red and upper-limits in blue.
The plot can be customised by changing the values in the table followed by the 'Re-plot' button. Data-points can be removed from the plot by de-selecting the left-hand check boxes or alternatively, new data-points can be added by entering values in the empty boxes.
The data can either be plotted with logarithmic (default) or linear axes.

SED Fitting

The broadband photometric data in the interactive table can be fitted to models of Young Stellar Objects (YSO) provided by Thomas Robitaille (2007ApJS..169..328). The data is fitted using his online fitting tool.
To use this fitting tool it is necessary to create a personal user login (click here for further information and to create login).
Alternatively, you can use use an automatic 'protostars' login by clicking the 'Login first' link. This will open up a second browser window and log you in using the username 'protostars'. Your login session will be active while your browser is left open, and you can then return to the Protostar object page and begin your fitting. Please note that when using the 'protostars' login, your fit will be viewable by other users and will be over-written when another user performs a fit.
Note that we are currently submitting all datapoints as monochromatic fluxes to the SED fitter. Please change them to broad/narrow-band if the correct filter (e.g. IRAC Band [1]) is available.
The parameters in the SED fitting box relate to Thomas Robitaille's fitting tool, and his documentation should be consulted for a full explanation.

Questions?

If you have any problems, comments or queries please do not hesitate to contact the webmaster of the protostar web-pages: df @ star.kent.ac.uk