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-835 DRP 2-D Pipeline <p>Spectral fitting of ETC simulator spectra in the same way as the SDSS fitting <a href="https://pfspipe.ipmu.jp/jira/browse/PIPE2D-651" title="Spectral fitting of SDSS spectra for flux calibration" class="issue-link" data-issue-key="PIPE2D-651">PIPE2D-651</a> for flux calibration. </p> PIPE2D-835

Spectral fitting of ETC simulator spectra for flux calibration

Story Normal Done Done Takuji Yamashita Takuji Yamashita flux-calibration Thu, 13 May 2021 07:16:49 +0000 Tue, 6 Jul 2021 04:49:12 +0000 Tue, 6 Jul 2021 04:49:12 +0000 0 3 <p>I did the chi-square fitting of the simulated spectra with the grid-interpolated AMBRE model templates. This fitting generates a probability distribution function of a reference model as functions of the stellar parameters. The PDF is combined with the PDF from broad-band SED fitting to determine the best fit model. This spectral fitting process takes ~110 min for a star with a single thread process.<br/>  <br/> Spectra: </p> <ul class="alternate" type="square"> <li>Simulated spectra: ETC simulator outputs of AMBRE models. 7.5min and 15min exposures.</li> <li>Grid-interpolated AMBRE templates: ~60000 templates. RBF interpolations at grid steps of delta_Teff = 50 K, delta_logg = 0.25, delta_Z = 0.0, delta_<span class="error">&#91;a/Fe&#93;</span> = 0.2, which roughly corresponds to a 1% flux accuracy.<br/>  </li> </ul> <p>This is an example of results.<br/> In the confidence contours, we can find that all the parameters are well determined. So, the spectrum of the minimum reduced chi-square is very similar to the input spectrum. Note that the flux (y-axis) is roughly scaled to match with each other at this time.</p> <p><span class="image-wrap" style=""><a id="13593_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/13593/13593_SFP_s6000_g%2B2.0_m1.0_t02_z%2B0.00_a%2B0.40.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Spec.png" title="SFP_s6000_g+2.0_m1.0_t02_z+0.00_a+0.40.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Spec.png" file-preview-type="image" file-preview-id="13593" file-preview-title="SFP_s6000_g+2.0_m1.0_t02_z+0.00_a+0.40.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Spec.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/13592/_thumb_13592.png" style="border: 0px solid black" /></a></span></p> <p><span class="image-wrap" style=""><a id="13594_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/13594/13594_SFP_p6000_g%2B4.5_m0.0_t01_z%2B0.00_a%2B0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png" title="SFP_p6000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png" file-preview-type="image" file-preview-id="13594" file-preview-title="SFP_p6000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/13593/_thumb_13593.png" style="border: 0px solid black" /></a></span></p> <p>This is another example.<br/> In this case, the Teff (5800 K) at the minimum red chi sq is lower than the input (6000 K). Therefore, its spectrum is redder than the input. The line widths are narrower than those of the input spectrum. The broad-band SED fitting of this case determined Teff more accurately than the spectral fitting. The combined PDF will find a better model template.</p> <p> <span class="image-wrap" style=""><a id="13595_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/13595/13595_SFP_p6000_g%2B4.5_m0.0_t01_z%2B0.00_a%2B0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Spec.png" title="SFP_p6000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Spec.png" file-preview-type="image" file-preview-id="13595" file-preview-title="SFP_p6000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Spec.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/13594/_thumb_13594.png" style="border: 0px solid black" /></a></span> <br/> <span class="image-wrap" style=""><a id="13596_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/13596/13596_BBP_p6000_g%2B4.5_m0.0_t01_z%2B0.00_a%2B0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png" title="BBP_p6000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png" file-preview-type="image" file-preview-id="13596" file-preview-title="BBP_p6000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/13595/_thumb_13595.png" style="border: 0px solid black" /></a></span> <br/>  </p> <p>The broad-band fitting PDF of this case. <br/> <span class="image-wrap" style=""><a id="13886_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/13886/13886_SFP_p7000_g%2B4.5_m0.0_t01_z%2B0.00_a%2B0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png" title="SFP_p7000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png" file-preview-type="image" file-preview-id="13886" file-preview-title="SFP_p7000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/13596/_thumb_13596.png" style="border: 0px solid black" /></a></span> </p> <p>The chi-square fitting of spectra works at &lt;~ 17 mag. These are the PDFs of 13 mag and 17 mag, respectively. In the case of 17 mag, Z and <span class="error">&#91;a/Fe&#93;</span> are determined, while Teff and Log(g) are weakly determined.<br/> The saw-shaped distributions of Z and <span class="error">&#91;a/Fe&#93;</span> come from the non-uniformity of the parameter grids of AMBRE. I will make up these gaps.<br/> Combined PDFs and the best-fit spectra are reported in <a href="https://pfspipe.ipmu.jp/jira/browse/PIPE2D-374" title="Combine P_HSC and P_PFS and construct the best-fit spectrum" class="issue-link" data-issue-key="PIPE2D-374"><del>PIPE2D-374</del></a>.<br/>  <br/>  <br/> r = 13 mag:</p> <p><span class="image-wrap" style=""><a id="13886_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/13886/13886_SFP_p7000_g%2B4.5_m0.0_t01_z%2B0.00_a%2B0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png" title="SFP_p7000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png" file-preview-type="image" file-preview-id="13886" file-preview-title="SFP_p7000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r13.0.txt.expt450s.Cont.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/13886/_thumb_13886.png" style="border: 0px solid black" /></a></span><br/>  <br/> r = 17 mag:<br/> <span class="image-wrap" style=""><a id="13887_thumb" href="https://pfspipe.ipmu.jp/jira/secure/attachment/13887/13887_SFP_p7000_g%2B4.5_m0.0_t01_z%2B0.00_a%2B0.00.AMBRE_Extp.ABmag_r17.0.txt.expt450s.Cont.png" title="SFP_p7000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r17.0.txt.expt450s.Cont.png" file-preview-type="image" file-preview-id="13887" file-preview-title="SFP_p7000_g+4.5_m0.0_t01_z+0.00_a+0.00.AMBRE_Extp.ABmag_r17.0.txt.expt450s.Cont.png"><img src="https://pfspipe.ipmu.jp/jira/secure/thumbnail/13887/_thumb_13887.png" style="border: 0px solid black" /></a></span></p> Blocks PIPE2D-647 Relates PIPE2D-651 Development Epic Link PIPE2D-303 Rank 0|zzs4wj:zzr Reviewers hassan Sprint 2DDRP-2021 A5 2DDRP-2021 A 6 Story Points 4.0