HIgh-energy LIght-curve GeneraTor (v1.5)

Overview

This web client returns measured count rates and upper limits from X-ray missions in standard energy bands, as supported by the mission instrumentation. Instrument count rates are converted into an in-band flux using a spectral model which may be selected by the user. Progress is registered by a widget which shows the percentage of missions which have finished processing. If the tool hangs then it can be restarted by refreshing the page.

A full description of the upper limit server and how values are calculated for the different missions can be found in the references

Changelog

1. Version 1.5 - (24/10/2024).

   Added support for NuSTAR.

   Added support for BeppoSAX.

   Swift-XRT now uses the LSXPS catalogue which includes all Swift-XRT data upto the latest processed datasets.

   Solved an issue with extracting upper limits from EXOSAT LE data.

   Small changes in the astrometry calibration used within the XMM-Newton files may lead to small (<5%) changes in calculated upper limits for XMM observations, compared to the previous version. Catalogue values are unaffected.

2. Version 1.4 - added support for HEAO-1 A2 detectors (16/3/2021).

3. Version 1.3 - Conversion factors updated using PIMMS v4.11a. Changes the returned flux by up to 5 percent for some instruments (5/1/2021).

4. Version 1.2 - added help for missing spectral model.

5. Version 1.1 - fixed problem with observation start and stop times in EXOSAT LE and Einstein results. This caused some results, from days with multiple observations at the same point, to be excluded. Added the option USECAT, to allow catalogued values to be recalculated. Improved the default plotting options.

6. Version 1.0 - original.

Current Known Problems

The XMM-Newton stacked upper limit server catalogue retrieval is not currently working and it is recommended to turn this off when running queries for the moment. This will be resolved with the next release of the XMM-Newton stacked catalaogue.

Mission

Click on the mission(s) you wish to use. The mission will be selected if the font is white, and not selected if the font is gray. The tool uses the following data:

1. All data for missions which have ceased to operate

2. All public data for XMM-Newton taken by the EPIC-pn telescope. This is typically, all calibration data, all data taken during slews and science data older than 1 year.

3. Swift-XRT: observations used in the creation of the LSXPS catalogue, which is made up from observations performed between January 1st 2005 and the most recently processed observations

4. INTEGRAL: One value is returned, for each energy band, integrated over all data available from launch until 2017

5. XMM-Newton stacked: One value is returned, for each energy band, integrated over all the observations made at that point on the sky. Note that the conversion from c/s to flux units is approximated by using the filter with the highest exposure time in the combined observation.

Input

1. Select what kind of input you wish to use: Target name, Coordinates or Input file.

   The Coordinates may be entered in either decimal degree or sexagesimal.

   54.260694 +47.646995

   23.6223 -34.567

   14:46:00 +68:16:24

   14 46 00 +68 16 24

   The files uploaded should be an ASCII file with one position per line and optionally a source name or identifier. RA, DEC and the (optional) source name must be spaced by a blank, and be in decimal degrees e.g.

   311.0406 -10.7235 MKN 509

   33.6398 -0.7667 MKN590

2. Optional:

   Modify the parameters in the Parameters box below

3. Press SUBMIT button

Parameters

Select the parameters according to your preferences for the output. The options available depend on the missions you have selected and on the rest of the parameters.

By default, all energy ranges available to a mission are selected. These can be turned off by pressing on the energy range.

A spectral model should be selected for converting instrument count rate into flux. The options are an absorbed power-law or black-body. The energy slope of the power-law or temperature of the black-body may be selected from a number of options. Similarly, the absorbing column in square centimetres may be chosen.

The tool returns the catalogue value if it exists. The system can be forced to recalculate the flux by setting usecat="No".

Credits

This tool makes use of data from the following locations:

1. The XMM-Newton science archive (https://www.cosmos.esa.int/web/xmm-newton/xsa)

2. Catalogue servers and instrument data files hosted at NASA's High Energy Astrophysics Science Archive Research Center (HEASARC; https://heasarc.gsfc.nasa.gov/).

3. A server for fluxes and upper limits from the Neil Gehrels Swift Observatory X-ray telescope (Swift-XRT) hosted at the UK Swift Science Data Centre (http://www.swift.ac.uk/LSXPS/processUL_JSON.php)

Spectral model missing

If the spectral model you need is not available in this web tool then you can get an accurate flux value from the instrument count rate by using the following strategy:

1. Go to the website https://heasarc.gsfc.nasa.gov/cgi-bin/Tools/w3pimms/w3pimms.pl
2. Select the mission with correct filter (if available) in the panel "Convert From"
3. Select "Flux" in the panel "Into"
4. Set input energy range to "default" (except for Swift XRT where you should select 0.3-2keV, 2-10keV and 0.3-10keV for soft, medium, and hard, respectively)
5. Select your desired output energy band (disclaimer: the output band should be geared to the mission energy band - for instance, extrapolating a 0.1-2.5keV ROSAT PSPC energy band to 0.2-12keV introduces large uncertainties!)
6. Set "Source Flux/Count rate" to 1.0
7. Specify the spectral parameters that you want to use.
8. Click "Estimate Count Rate"
9. The output page will yield something like "PIMMS predicts a flux (X.XXX-X.XXXkeV) of YYYY ergs/cm/cm/s"
10. Run your search on the HILIGT webpage for any spectral model
11. Manually multiply the count rate value on the HILIGT output page with the conversion factor YYYY"