EDP Sciences logo
Subscriber Authentication Point
Search
Menu
Home All issues Volume 655 (November 2021) A&A, 655 (2021) A53 Full HTML
Free Access

Table 4.

Fitting power law continuum to individual one hour spectra for the quasar J022836.08+000939.

ID Uncorrected Margala Our correction Our correction DR16
(σ = const.) (σ = const.) (σ = f(λ)) (σ = const.)
−α σα −α σα −α σα −α σα −α σα
1 −0.59 0.01 1.32 −1.11 0.01 1.39 −1.27 0.01 1.44 −1.28 0.01 1.41 −1.11 0.01 1.51
2 −0.61 0.01 1.26 −1.03 0.01 1.34 −1.17 0.01 1.39 −1.22 0.01 1.36 −1.05 0.01 1.43
3 −0.58 0.01 1.64 −1.04 0.01 1.81 −1.17 0.01 1.92 −1.21 0.01 1.86 −1.08 0.01 2.01
4 0.41 0.01 1.34 −0.57 0.01 1.49 −0.64 0.01 1.57 −0.72 0.01 1.48 −0.68 0.02 1.63
5 0.08 0.01 1.11 −0.76 0.02 1.22 −0.94 0.02 1.30 −1.07 0.02 1.22 −0.96 0.01 1.14
6 0.08 0.01 1.19 −0.73 0.01 1.28 −0.77 0.01 1.32 −0.86 0.01 1.27 −0.85 0.01 1.33
7 −0.17 0.01 0.97 −1.23 0.01 1.11 −1.26 0.01 1.15 −1.32 0.01 1.08 −1.15 0.02 1.25
8 0.46 0.02 1.25 −0.45 0.02 1.35 −0.64 0.02 1.43 −0.76 0.02 1.36 −0.57 0.02 1.29
μ −0.11 1.26 −0.86 1.37 −0.98 1.44 −1.05 1.38 −0.93 1.45
σμ 0.42 0.26 0.25 0.23 0.20
0.15 0.09 0.09 0.08 0.07

Notes. The σ on the second line of the header refers to the seeing profile i.e. Eq. (6). The first column corresponds to the ID in Table 2. Columns 2–4 relate to uncorrected spectra. The second and the third columns give the best-fit spectral index, Eq. (18), and its error (σα). The fourth column is the best-fit normalised , i.e. Eq. (19) normalised by the number of degrees of freedom in the fit. The same pattern of three columns is repeated for each of the four correction methods. The last three lines in this table labelled μ, σμ, and , give the unweighted mean spectral index, its standard deviation, and in the last line, the error on the mean. For comparison, the best-fit spectral index obtained (in the same way) using the SDSS DR7 spectrum is −0.65 ± 0.02. The mean value of gives an indication of the overall quality of fit.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.