From c758063f7cae164d03157c090f279edc991e3c2b Mon Sep 17 00:00:00 2001 From: biboyd Date: Sun, 23 Aug 2020 20:47:49 -0400 Subject: [PATCH] add to statement of need --- docs/source/index.rst | 7 +++++++ paper.md | 37 +++++++++++++++++++++---------------- 2 files changed, 28 insertions(+), 16 deletions(-) diff --git a/docs/source/index.rst b/docs/source/index.rst index df61104..22d5cbe 100644 --- a/docs/source/index.rst +++ b/docs/source/index.rst @@ -12,6 +12,13 @@ projects utilized to achieve this. Accessing simulation data is done using yt. Trident is used to generate synthetic sightlines/lightrays and generate synthetic spectra. Spectacle is used to fit voigt profiles to spectra and extract absorbers. +Observational studies generate large absorber catalogs by studying the absorption +line spectra of distant quasars, as their light passes through intervening galaxies. +Salsa can generate similar catalogs from cosmological and galactic simulations, +allowing research to study these simulations from an observers perspective. This +can give new insights into the data as well as help facilitate comparisons and +collaboration between simulations and observations + In addition a novel method for extracting absorbers, the SPICE method. This uses cell level data to extract absorbers from a Trident lightray and returns a great deal of information that can be further analyzed. diff --git a/paper.md b/paper.md index a3c220d..3e6515e 100644 --- a/paper.md +++ b/paper.md @@ -69,25 +69,30 @@ Absorption Line Surveyor Application). SALSA is a package that generates synthetic absorber catalogs by studying the LightRays and/or spectra generated using Trident. SALSA provides an automated pipeline to process large numbers of LightRays and extract absorber information into a catalog for further analysis. -Two separate methods are made available to extract absorbers. The “Spectacle -method” uses the Python package Spectacle[^2] to fit Voigt profiles to the -synthetic spectra generated by Trident (see \autoref{fig:1}) [@spectacle]. This -method provides traditional absorption line information (e.g. Doppler broadening, -equivalent width, etc.) and thus creates synthetic absorber catalogs very similar -to those made from observational studies. +One large benefit to studying these synthetic catalogs is the ability to directly +compare to observational catalogs. This can give new insights into the +data as well as help facilitate collaboration between simulators and observers. # Summary -The “SPICE (Simple Procedure for Iterative Cloud Extraction) method” is a novel -method that uses cell level data from the simulation to find the contiguous -groups of cells which will meaningfully contribute absorption line features to -the synthetic spectra. It does this through an iterative process that isolates -the regions along the LightRay with the highest number density values and -returns those regions with observationally detectable column densities as -individual absorbers (see \autoref{fig:1} or for more details, the documentation[^3]). -This method provides direct access to the information contained in the simulation -(e.g. temperature, velocity, metallicity, etc.) and, in turn, more information -than can be provided by spectral absorption line analysis alone. +Two separate methods are made available to extract absorbers. The “Spectacle +method” uses the Python package Spectacle[^2] to fit Voigt profiles to the +synthetic spectra generated by Trident (see \autoref{fig:1}) [@spectacle]. This +method provides traditional absorption line information (e.g. Doppler +broadening, equivalent width, etc.) and thus creates synthetic absorber +catalogs very similar to those made from observational studies. + +The second method, called the “SPICE (Simple Procedure for Iterative Cloud +Extraction) method”, is a novel method that uses cell level data from the +simulation to find the contiguous groups of cells which will meaningfully +contribute absorption line features to the synthetic spectra. It does this +through an iterative process that isolates the regions along the LightRay with +the highest number density values and returns those regions with +observationally detectable column densities as individual absorbers (see +\autoref{fig:1} or for more details, the documentation[^3]). This method +provides direct access to the information contained in the simulation (e.g. +temperature, velocity, metallicity, etc.) and, in turn, more information than +can be provided by spectral absorption line analysis alone. ![These plots were generated using FOGGIE simulation data [@Peeples:2019]. The top plot shows the number density profile of O VI along the length of the