tag:blogger.com,1999:blog-1074502515186128083.post3608074906581612960..comments2023-11-14T12:59:44.505-05:00Comments on Hogg's Ideas: predict spectra using photometryHogghttp://www.blogger.com/profile/18398397408280534592noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-1074502515186128083.post-60338419077665869822020-05-13T16:55:06.865-04:002020-05-13T16:55:06.865-04:00Professor Hogg,
I'm only 6 years late to this...Professor Hogg,<br /><br />I'm only 6 years late to this party, but I wonder if you're still interested in this project or have made any progress on it. This kind of study is exactly something I've been experimenting with for white dwarfs, albeit that is probably a much simpler problem. The white dwarf optical spectrum is essentially entirely determined by the temperature and surface gravity, which are strongly constrained by the photometry. <br /><br />In our implementation we used simple artificial neural networks to reconstruct the spectrum from labels or photometry. With a dataset of 5000 SDSS white dwarfs, the reconstructions were quite satisfactory using 2-band photometry. My main goal for this project was to generate predicted spectra using photometry, and then compare the predicted spectrum to actual spectroscopic measurements. By characterizing the goodness/badness of fit, interesting outlier stars fall out of the dataset. I have since put this project on hold, but I hope to restart it sometime in the future. <br /><br />Extending this methodology beyond white dwarfs would be very interesting. I think one big improvement could be deconvolutional neural networks, where the deconvolution layers could intelligently reconstruct spectral features from the limited input parameter space. There's only so many constraints we can get from two-band photometry, but I wonder how much prediction power we'd gain by adding photometric bands - I'd imagine certain bands would work well for certain abundances and metallicities. <br /><br />These are just some thoughts of my own, I'm curious if you've developed/are interested in developing this idea further. <br /><br />Vedant Chandrahttps://www.blogger.com/profile/12105928130001026185noreply@blogger.comtag:blogger.com,1999:blog-1074502515186128083.post-25067827822817014622014-07-11T03:35:12.918-04:002014-07-11T03:35:12.918-04:00Asensio Ramos points me to this paper, which is VE...Asensio Ramos points me to this paper, which is VERY RELEVANT http://adsabs.harvard.edu/abs/2010ApJ...719.1759AHogghttps://www.blogger.com/profile/18398397408280534592noreply@blogger.com