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-511 DRP 2-D Pipeline <p>Attempt to make parameter interpolations of stellar model templates using a single 4D radial basis function (RBF) which is modeled over all the original model templates. </p> <p>The 4D RBF interpolations using neighboring model templates reproduce model spectra with high quality (&lt;1%) as reported in <a href="https://pfspipe.ipmu.jp/jira/browse/PIPE2D-460" class="external-link" rel="nofollow">PIPE2D-460</a> but the processes are time-consuming because RBF models are generated at every parameter grid. In this ticket, we try to reduce the processing time by using only a single RBF. </p> PIPE2D-511

Parameter interpolation of model templates with a single 4D RBF model

Story Normal Done Done Takuji Yamashita Takuji Yamashita flux-calibration model-templates Wed, 29 Jan 2020 10:17:38 +0000 Mon, 20 Dec 2021 03:02:45 +0000 Mon, 20 Dec 2021 03:02:45 +0000 0 3 <p>The interpolation using a single 4D RBF has been tested at an existing parameter point. The parameters are Teff, log(g), Z, and alpha elements. The result is as follows:</p> <p>The processing time to make an RBF model: ~ 12 hours <br/> The accuracy of a produced spectrum: 0.02 % (for a test sample)</p> <p>Once the RBF model is generated, we can get an interpolated spectrum immediately. The accuracy is good enough.</p> <p>I will check the accuracies at several parameter points as well.</p> <p>The accuracies of this interpolation has been evaluated at 192 existing parameter points. An AMBRE original spectrum is removed when an interpolation is made there. The parameter points for this evaluation were selected to cover the whole grids. To save the processing time, the interpolations were made at 380-500nm, where the accuracies are expected to be worse than redder wavelengths. </p> <p>The RMS (%) is r.m.s of residuals between an AMBRE spectrum and a generated interpolation. The spectra are convolved with a quasi LSF (a Gaussian with 0.2 nm FWHM).  </p> <p>Almost all the interpolations were generated in high accuracies (less than 1%), but 12% show &gt;1% RMS. 1% show &gt;10% RMS. I cannot any clear correlation of RMS to any parameters. When Teff and log(g) are fixed, at a specific metallicity interpolation spectra systematically show worse RMS. The reason on this and treatment for these low-accuracy interpolations are under discussion. </p> <p> </p> <p>RMS</p> <p><span class="image-wrap" style=""><a id="12601_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/12601/12601_RMS_single4DRBF_2020March30_teff7000_logg4.png" title="RMS_single4DRBF_2020March30_teff7000_logg4.png" file-preview-type="image" file-preview-id="12601" file-preview-title="RMS_single4DRBF_2020March30_teff7000_logg4.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/12600/_thumb_12600.png" height="480" width="480" style="border: 0px solid black" /></a></span></p> <p> </p> <p>RMS at Teff=7000 and log(g) = 4.0</p> <p><span class="image-wrap" style=""><a id="12601_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/12601/12601_RMS_single4DRBF_2020March30_teff7000_logg4.png" title="RMS_single4DRBF_2020March30_teff7000_logg4.png" file-preview-type="image" file-preview-id="12601" file-preview-title="RMS_single4DRBF_2020March30_teff7000_logg4.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/12601/_thumb_12601.png" height="464" width="464" style="border: 0px solid black" /></a></span></p> <p> </p> <p>We can close this ticket because we have developed the parameter interpolation and we have evaluated this method in <a href="https://pfspipe.ipmu.jp/jira/browse/PIPE2D-460" title="Evaluate the interpolations between model templates" class="issue-link" data-issue-key="PIPE2D-460"><del>PIPE2D-460</del></a>. The code implementation should be done in <a href="https://pfspipe.ipmu.jp/jira/browse/PIPE2D-781" title="Organize the drp_fstar repository " class="issue-link" data-issue-key="PIPE2D-781"><del>PIPE2D-781</del></a>.</p> Blocks PIPE2D-365 PIPE2D-781 Development Epic Link PIPE2D-303 Rank 0|02qpt6:508yl0chzzy0000q01r9 Reviewers hassan Sprint 2DDRP-2020 A Story Points 4.0