We present velocity-channel maps and analysis of the warm ionized medium
(WIM) throughout the Sagittarius- Carina arm at Galactic longitudes 20 < l < 52
and 282 < l < 332. Using Wisconsin H-Alpha Mapper observations of H-alpha and
S II 6716 emission, the structure of the WIM along a longitude-velocity track
corresponding to CO emission in the plane is isolated. Exponential scale
heights of electron density squared (or emission measure) are determined using
H-alpha emission above (below) the midplane to be 330 plus/minus 80 pc (550
plus/minus 230 pc) along the near Sagittarius arm, 300 plus/minus 100 pc (250
plus/minus 30 pc) along the near Carina arm, and > 1000 pc along the far Carina
arm. Physical conditions of the ionized gas are analyzed using the S
II/H-alpha line ratio, which more closely traces H-alpha intensity than height
above the plane, z, suggesting a stronger relationship with the in-situ
electron density. We interpret this result as further evidence for the majority
of the observed diffuse emission originating from in-situ ionized gas as
opposed to scattered light from classical H II regions in the plane.
Description
[1610.08785] A Study of the Warm Ionized Medium Throughout the Sagittarius-Carina Arm
%0 Generic
%1 krishnarao2016study
%A Krishnarao, Dhanesh
%A Haffner, L. Matthew
%A Benjamin, Robert A.
%D 2016
%K ionized medium milky warm way
%T A Study of the Warm Ionized Medium Throughout the Sagittarius-Carina Arm
%U http://arxiv.org/abs/1610.08785
%X We present velocity-channel maps and analysis of the warm ionized medium
(WIM) throughout the Sagittarius- Carina arm at Galactic longitudes 20 < l < 52
and 282 < l < 332. Using Wisconsin H-Alpha Mapper observations of H-alpha and
S II 6716 emission, the structure of the WIM along a longitude-velocity track
corresponding to CO emission in the plane is isolated. Exponential scale
heights of electron density squared (or emission measure) are determined using
H-alpha emission above (below) the midplane to be 330 plus/minus 80 pc (550
plus/minus 230 pc) along the near Sagittarius arm, 300 plus/minus 100 pc (250
plus/minus 30 pc) along the near Carina arm, and > 1000 pc along the far Carina
arm. Physical conditions of the ionized gas are analyzed using the S
II/H-alpha line ratio, which more closely traces H-alpha intensity than height
above the plane, z, suggesting a stronger relationship with the in-situ
electron density. We interpret this result as further evidence for the majority
of the observed diffuse emission originating from in-situ ionized gas as
opposed to scattered light from classical H II regions in the plane.
@misc{krishnarao2016study,
abstract = {We present velocity-channel maps and analysis of the warm ionized medium
(WIM) throughout the Sagittarius- Carina arm at Galactic longitudes 20 < l < 52
and 282 < l < 332. Using Wisconsin H-Alpha Mapper observations of H-alpha and
[S II] 6716 emission, the structure of the WIM along a longitude-velocity track
corresponding to CO emission in the plane is isolated. Exponential scale
heights of electron density squared (or emission measure) are determined using
H-alpha emission above (below) the midplane to be 330 plus/minus 80 pc (550
plus/minus 230 pc) along the near Sagittarius arm, 300 plus/minus 100 pc (250
plus/minus 30 pc) along the near Carina arm, and > 1000 pc along the far Carina
arm. Physical conditions of the ionized gas are analyzed using the [S
II]/H-alpha line ratio, which more closely traces H-alpha intensity than height
above the plane, z, suggesting a stronger relationship with the in-situ
electron density. We interpret this result as further evidence for the majority
of the observed diffuse emission originating from in-situ ionized gas as
opposed to scattered light from classical H II regions in the plane.},
added-at = {2016-10-28T09:28:22.000+0200},
author = {Krishnarao, Dhanesh and Haffner, L. Matthew and Benjamin, Robert A.},
biburl = {https://www.bibsonomy.org/bibtex/298f555e976faf6dc5391393ced334fc9/miki},
description = {[1610.08785] A Study of the Warm Ionized Medium Throughout the Sagittarius-Carina Arm},
interhash = {6b6e1fbd55a7d12efc1564fd4caed5ea},
intrahash = {98f555e976faf6dc5391393ced334fc9},
keywords = {ionized medium milky warm way},
note = {cite arxiv:1610.08785},
timestamp = {2016-10-28T09:28:22.000+0200},
title = {A Study of the Warm Ionized Medium Throughout the Sagittarius-Carina Arm},
url = {http://arxiv.org/abs/1610.08785},
year = 2016
}