 |
The WFC3 grism modeBesides imaging, WFC3 offers slitless spectroscopy on both the ultra-violet/optical (UVIS) and infrared (IR) channels. The UVIS channel is equipped with the G280 grism, which has a resolving power R~70 in the wavelength range 200-400nm. The IR channel includes the grisms G102 and G141 with resolving powers R~210 in the range 800-1150nm and R~130 in the range 1100-1700nm, respectively. Further information on WFC3 is available on the WFC3 STScI pages. The WFC3 grism calibration files and the grism simulation applicationThe ST-ECF is responsible for supporting the WFC3 slitless spectroscopic modes. As part of this support, we provide the calibration and reference files for the three WFC3 grisms which can be used together with our spectral extraction software aXe. We have also developed aXeSIM, a dedicated software package to simulate 2-dimensional WFC3 slitless spectroscopic images. In order to mimic observational data very closely, aXeSIM also can optionally produce a matching direct image (through a user-selected filter) for each slitless image.
The following link allows to simulate WFC3 slitless images via a Web application:
DisclaimerThe WFC3 slitless image simulator was developed independently of the STScI Exposure Time Calculator (ETC). While every effort has been made to ensure that the imaging simulator provides similar estimates of detected counts to the ETC, differences are bound to result. The STScI ETC is to be taken as the official tool and should be used to determine exposure times for the purposes of critical time justification in Phase I and II. The WFC3 ETC can be found here. WFC3 calibration and reference filesUPDATE (24-Nov-2009): The sensitivity files of WFC3 IR grism modes which are used in aXe data reduction package and in the simulation package aXeSIM were updated to reflect the in-orbit performance as derived from SMOV and early Cycle17 calibration programs. A detaield report of the calibrations can be found in Instrument Science Reports WFC3-ISR-2009-17 and WFC3-ISR-2009-18. The UV channel calibration files remain largely unchanged since the Thermal Vac ground calibrations. As soon as the Cycle 17 calibration programs are analysed we will publish the updated infoprmation here. The configuration and calibration files presented on this page are in the correct format to be used with the aXe simulation software aXeSIM and the aXe extraction software aXe. To use these calibration products with aXe and aXeSIM, copy them into a directory and set your AXE_CONFIG_PATH environment variable to point to that directory. UVIS/G280 grism
IR/G102 grism
IR/G141 grism
Maintained by Harald Kuntschener <hkuntsch@eso.org> |
 |
 |