https://pfspipe.ipmu.jp/jira This file is an XML representation of an issue en-us 8.3.4 803005 13-09-2019 https://pfspipe.ipmu.jp/jira/browse/PIPE2D-645 DRP 2-D Pipeline <p>As shortly discussed on SPS telecon on October 21, 2020 and on Slack DRP-2D, <a href="https://pfspipe.ipmu.jp/jira/secure/ViewProfile.jspa?name=fmadec" class="user-hover" rel="fmadec">fmadec</a> reports a) changing FWHM in the data on the level of cca 10% and b) LSF being described with a well-sampled Gaussian c) Are the wings really as strongly suppressed as a Gaussian?</p> <p> </p> <p>The report is at <a href="https://sumire.pbworks.com/w/file/fetch/141725733/LAM_Subaru_SM1_LSF_20201013.pdf" class="external-link" rel="nofollow">https://sumire.pbworks.com/w/file/fetch/141725733/LAM_Subaru_SM1_LSF_20201013.pdf</a></p> <p> </p> <p><a href="https://pfspipe.ipmu.jp/jira/secure/ViewProfile.jspa?name=arnaud.lefur" class="user-hover" rel="arnaud.lefur">arnaud.lefur</a> reports that the visits used are:</p> <p>medRes,argon:25914..25937<br/> medRes,neon:25938..25961<br/> lowRes,argon:26524..26547<br/> lowRes,neon:26548..26571 </p> <p> </p> <p>Verify these claims</p> PIPE2D-645

Verify - changing FWHM around 10% and well-sampled Gaussian LSF

Task Normal Done Done ncaplar ncaplar Wed, 21 Oct 2020 23:39:31 +0000 Wed, 17 Mar 2021 21:22:36 +0000 Wed, 17 Mar 2021 21:08:08 +0000 0 2 <p>I have analyzed low res data. I have added a recreation of the plot made by <a href="https://pfspipe.ipmu.jp/jira/secure/ViewProfile.jspa?name=fmadec" class="user-hover" rel="fmadec">fmadec</a> using a different set of data (but still Subaru). The FWHM has been estimated by fitting a Gaussian to the data and measuring FWHM of the modeled Gaussian. I see the same effect that Fabrice reported. I have also added 2d plots showing how FWHM depends as a function of the position on the detector. Two panels show results that depend along which axis I extract the data - the left panel is extracted along the wavelength dimension (so actual LSF), while the right panel is extracted along the perpendicular dimension.</p> <p>Obviously, there is quite a bit of change. I will discuss this with Jim.</p> <p> </p> <p>How good is the Gaussian fit?  You could fit a Gaussian to a top-hat and get widths like that, but that wouldn't mean that the data was well-sampled.</p> <p> </p> <p>Yes, yes, this was just an interim report. Work ongoing...</p> <p>This was discussed on PFS technical telecom on March 15,2021.</p> <p>The conclusions is that Gaussian provides semi-good fit, but obviously there are deviations in particular in wings where Gaussian dramatically underestimates flux.<br/> It is not clear that there is much value in quantitative analysis that I did (FFT of data-model). We agreed that it is not worth spending a lot more time on this. Closing now and possibly reopening in a new ticket if further quantitative analysis is wanted. </p> <p>I don't think it's worth more of your time.  You've looked more carefully than Fabrice did.</p> Development Rank 0|02qpt6:508yl0chzzy0000p920zzzzzzy Sprint 2DDRP-2021 A 2DDRP-2021 A 2 2DDRP-2021 A3 Story Points 2.0