WEBPIMMS is a Web tool based on PIMMS (the Portable Interactive Multi-Mission Simulator) created by Koji Mukai. WEBPIMMS implements a subset of the functionalities of the command line PIMMS. It allows easy access and use without the need to install the software, but WEBPIMMS does not have all the functionality of the command line version.
An example is comparing what Swift will see from a GRB similar to one that was observed by BeppoSAX. Take a GRB with a peak count rate in the SAX/MECS detector of 65 counts/s, that is in its early phase, and was measured to be well-described by a power law with a photon index 1.2. What would Swift observe?
To perform this comparison using WEBPIMMS do the following.
The WEBPIMMS output screen (see below) summarizes the input parameters and displays estimated count rates for the XRT, BAT and UVOT. More information about the response matrices used can be found on the SSC Web site.
Output from PIMMS Input Parameters: Model #1: Power Law Model #2: Model #3: Model #4: P_l/keV: 1.2 P_l/kev: P_l/keV #3: Galactic nH: 1e19 cm-2 Intrinsic nH: 0.0 //cm-2 Redshift: 0.65 From: sax mecs Output Flux energy range: keV; Count Rate: 65 cps Internal model normalization = 1.174E+00 Redshifted with z= 0.6500 and a Galactic Hh= 1.000E+19 Useful mission related information may be found at: http://swiftsc.gsfc.nasa.gov/ http://heasarc.gsfc.nasa.gov/docs/sax/inst_papers.html SWIFT XRT PIMMS predicts 1.429E+02 cps with SWIFT XRT PC (Grade 0-12 on-axis count rate for an infinite extraction region) or 1.117E+03 cps in Grade 0 SWIFT XRT PIMMS predicts 1.521E+02 cps with SWIFT XRT WT (Grade 0-12 on-axis count rate for an infinite extraction region) or 1.401E+02 cps in Grade 0 SWIFT XRT PIMMS predicts 1.632E+02 cps with SWIFT XRT PD (Grade 0-12 on-axis count rate for an infinite extraction region) or 1.591E+02 cps in Grade 0 SWIFT BAT PIMMS predicts 9.052E-02 cps with SWIFT BAT SINGLE (Channel 3-78 count rate per fully illuminated detector) With 0.2620 background cps, it can be detected at S/N=5.0 in 0.204 s Results in the 4 standard Swift/BAT survey bands are: Channel / Energy Source BGD Detection 3-7 / 14-24 keV 0.020 0.0766 1.127 s 8-19/ 24-48.9 keV 0.033 0.0835 0.510 s 20-41/48.9-98.8 keV 0.030 0.0646 0.496 s 42-78/98.8-194.9 keV 7.828E-03 0.0373 3.662 s Note PIMMS is primarily an X-ray tool, and extrapolation to the UV regime introduces additional uncertainties. In particular, PIMMS assumes E(B-V) = N_H / 4.8E+21 and an average Milky Way extinction law. SWIFT UVOT PIMMS predicts 1.305E+01 cps with SWIFT UVOT UVW1 SWIFT UVOT PIMMS predicts 8.418E+00 cps with SWIFT UVOT UVM2 SWIFT UVOT PIMMS predicts 1.982E+01 cps with SWIFT UVOT U SWIFT UVOT PIMMS predicts 1.481E+01 cps with SWIFT UVOT B SWIFT UVOT PIMMS predicts 5.610E+00 cps with SWIFT UVOT V SWIFT UVOT Note: Grisms still use pre-flight effective area files PIMMS predicts 9.199E+01 cps with SWIFT UVOT UGRISM SWIFT UVOT Note: Grisms still use pre-flight effective area files PIMMS predicts 8.686E+01 cps with SWIFT UVOT VGRISM SWIFT UVOT PIMMS predicts 9.497E+01 cps with SWIFT UVOT WHITE