|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'501'711
Articles rated: 2609
19 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
Testing ASTRO-H Measurements of Bulk and Turbulent Gas Motions in Galaxy Clusters | | Naomi Ota
; Daisuke Nagai
; Erwin T. Lau
; | | Date: |
10 Jul 2015 | | Abstract: | Gas motions in galaxy clusters play important roles in determining the
properties of the intracluster medium (ICM) and constraining cosmological
parameters using X-ray and Sunyaev-Zel’dovich effect observations of galaxy
clusters. The upcoming ASTRO-H mission, equipped with high-resolution X-ray
spectrometer, will make the first direct measurements of gas motions in galaxy
clusters through measurements of Doppler shifting and broadening of emission
lines. However, the physical interpretation of the data will be challenging due
to the complex thermal and velocity structures of the ICM. In this work, we
investigate how well we can measure bulk and turbulent gas motions in the ICM
with ASTRO-H, by analyzing mock ASTRO-H simulations of galaxy clusters
extracted from cosmological hydrodynamic simulations. We assess how photon
counts, spectral fitting methods, multiphase ICM structure, deprojections, and
region selection affect the measurements of gas motions. We show that while
ASTRO-H is capable of recovering the underlying spherically averaged velocity
profiles to within 20% with reasonable amount of photon counts (>~200) in the
6.7 keV Fe XXV line complex, there are considerable azimuthal variations in the
ICM velocities, even in dynamically relaxed systems, which must be taken into
account when interpreting data and developing observing strategies. Finally, we
show that ASTRO-H should enable direct measurements of the hydrostatic mass
bias with an accuracy of <~5%, by accounting for both rotational and random
velocities from Doppler shifts and broadening of emission lines. Our results
are broadly applicable for future X-ray missions, such as Athena+ and SMART-X. | | Source: | arXiv, 1507.2730 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER