J/A+A/608/A139 237 Lyman-alpha spectra of MUSE-Wide survey (Gronke, 2017)
Modeling 237 Lyman-alpha spectra of the MUSE-Wide survey.
Gronke M.
<Astron. Astrophys. 608, A139 (2017)>
=2017A&A...608A.139G 2017A&A...608A.139G (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, spectra ; Models
Keywords: radiative transfer - galaxies: high-redshift - line: formation -
line: profiles - scattering
Abstract:
We compare 237 Lyman-α (Lyα) spectra of the "MUSE-Wide
survey" (Herenz et al., 2017, Cat. J/A+A/606/A12) to a suite of
radiative transfer simulations consisting of a central luminous source
within a concentric, moving shell of neutral gas, and dust. This six
parameter shell-model has been used numerously in previous studies,
however, on significantly smaller data-sets. We find that the
shell-model can reproduce the observed spectral shape very well -
better than the also common 'Gaussian-minus-Gaussian' model which we
also fitted to the dataset. Specifically, we find that ∼94% of the
fits possess a goodness-of-fit value of p(chi2)>0.1. The large
number of spectra allows us to robustly characterize the shell-model
parameter range, and consequently, the spectral shapes typical for
realistic spectra. We find that the vast majority of the Lyα
spectral shapes require an outflow and only ∼5% are well-fitted
through an inflowing shell. In addition, we find ∼46% of the spectra
to be consistent with a neutral hydrogen column density <1017cm-2
-- suggestive of a non-negligible fraction of continuum leakers in the
MUSE-Wide sample. Furthermore, we correlate the spectral against the
Lyα halo properties against each other but do not find any
strong correlation.
Description:
Shell-model parameters of the 237 Lyα spectra presented in the
first instalment of the MUSE-Wide survey (Herenz et al., 2017, Cat.
J/A+A/606/A12). For each spectrum, the MUSE UNIQUE ID, the p(chi2)
value of the best fit, and the six shell-model parameters (plus their
uncertainty) are given. In particular, for each parameter, the
(16,50,84)th percentiles of the likelihood are outputted.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sm-fits.dat 305 237 *Shell-model parameters
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Note on sm-fits.dat: Suffixes -16, -50, -84 indicate the 16th, 50th and 84th
percentiles of the posterior, respectively.
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See also:
J/A+A/606/A12 : MUSE-Wide survey: 831 emission line galaxies (Herenz+, 2017)
Byte-by-byte Description of file: sm-fits.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- MUSE MUSE UNIQUE ID
11- 26 F16.11 km/s Dv-16 16th percentile of intrinsic shift
28- 46 F19.14 km/s Dv-50 Intrinsic shift
48- 63 F16.11 km/s Dv-84 84th percentile of intrinsic shift
65- 77 F13.10 [cm-2] logNHI-16 16th percentile of shell column density (1)
79- 91 F13.10 [cm-2] logNHI-50 Shell column density (1)
93-105 F13.10 [cm-2] logNHI-84 84th percentile of shell column density (1)
107-119 F13.11 [K] logT-16 16th percentile of effective temperature of
shell (1)
121-133 F13.11 [K] logT-50 Effective temperature of shell (1)
135-147 F13.11 [K] logT-84 84th percentile of effective temperature of
shell (1)
149-162 F14.10 km/s sigmai-16 16th percentile of intrinsic width of
Lyα line
164-177 F14.10 km/s sigmai-50 Intrinsic width of Lya line
179-192 F14.10 km/s sigmai-84 84th percentile of intrinsic width of
Lyα line
194-207 F14.12 --- taud-16 16th percentile of (absorbing) dust optical
detph
209-222 F14.12 --- taud-50 (absorbing) dust optical detph
224-237 F14.12 --- taud-84 84th percentile of (absorbing) dust optical
detph
239-254 F16.11 km/s vexp-16 16th percentile of expansion velocity
256-271 F16.11 km/s vexp-50 Expansion velocity (2)
273-287 F15.10 km/s vexp-84 84th percentile of expansion velocity
289-305 E17.15 --- Pchi2 p(chi^2) of the best fit
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Note (1): log stands for the logarithm with base 10
Note (2): Negative values stand for inflow.
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Acknowledgements:
Max Gronke, maxbg(at)astro.uio.no
(End) Max Gronke [Oslo, Norway], Patricia Vannier [CDS] 25-Sep-2017