deletions | additions       diff --git a/sectionMethdology_To.tex b/sectionMethdology_To.tex  index be05e10..c7ca382 100644  --- a/sectionMethdology_To.tex  +++ b/sectionMethdology_To.tex 
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We investigate the velocity structure of our filaments in two ways: first, whenever possible, we establish the velocity contiguity of our candidates by performing a slice extraction along each filamentary extinction feature in \href{http://www.glueviz.org/en/stable/index.html}{Glue}, a visualization tool that facilitates the linking of data sets. We link spectral \textit{p-p-v} cubes from the GRS and ThrUMMS survey with GLIMPSE-Spitzer mid-infrared images and obtain velocity as a function of position along a path that traces the entire extinction feature. The results of the slice extraction along the path of one of our strongest bone candidates is shown in figure \ref{fig:filament5_slice}. We are able to establish velocity coherence for all candidates lying within the coverage range of the GRS survey ($ 18^\circ < l < 56^\circ$) and the ThrUMMS survey ($300^\circ < l < 358^\circ$). We also confirm that this GRS or ThrUMMS-determined velocity agrees with the velocity of dense gas tracers to within 5 km/s.  Next, we ensure that the candidates are contiguous in velocity space as traced mainly by high-density emission from the HOPS, MALT90, and BGPS surveys. In cases where HOPS, MALT90, and BGPS catalog data are not available along the extinction feature, we also extract spectra from GRS and MALT90 \textit{p-p-v} cubes using the spectrum extractor tool in Glue. We once again link spectral \textit{p-p-v} cubes from the GRS survey with GLIMPSE-Spitzer mid-infrared images and use the spectrum-extractor tool to obtain velocities along different regions of the extinction feature; a demonstration of the procedure used to extract velocities in Glue is shown in the appendix. appendix (see section Glue Demo II).  Since CO traces lower density gas ($\sim 10^2 \textrm{ cm}^{-3}$) and $\mathrm{N_2H+}$, $\textrm{HCO}^+$, and $\textrm{NH}_3$ trace high density gas ($\sim 10^4 \textrm{ cm}^{-3}$), the dense gas sources provide much stronger evidence for the velocity of cold, dense, filamentary IRDCs. However, where dense gas sources are not available, the complete and unbiased high resolution GRS survey, although less desirable, allows us to roughly gauge the velocity along entire lengths of filaments. By overlaying the HOPS, MALT90, BGPS, and GRS determined velocities on a \textit{p-v} diagram of CO emission, we establish whether these filaments are associated with an existing spiral arm trace. For this study, we first use the whole-galaxy \citet{Dame_2001} CO survey to roughly locate each of the arms in \textit{p-p-v} space. We then overplot spiral fits to CO and HI for various spiral arm models, to determine whether candidates are consistent with previously claimed spiral arm traces. Of the approximately fifteen candidates identified visually, ten of these candidates are within 10 km/s of the Scutum-Centaurus and Norma-4kpc/Norma-Cygnus arms. We plot these ten candidates in \textit{p-p-v} space in figure \ref{fig:skeleton}. In addition to showing our Bone candidates, we show several different predictions of the positions of two spiral arms toward the inner Galaxy in longitude-velocity space, from \citet{Dame_2011}, \citet{Sanna_2014}, \citet{Shane_1972}, and \citet{Vallee_2008}. We also include Scutum-Centaurus and Norma fits from \citet{Reid_2015}, derived from trigonometric parallax measurements of high-mass star forming regions taken as part of the BeSSeL survey \citep{Reid_2014}. \citet{Reid_2015} produce fits with ($l,b,v$) loci that closely follow GMCs that trace the arms, producing a rough log-spiral approximation determined by trigonometric parallax rather than an assumed Galactic rotation curve.