A Non-parametric Analysis of the CMB Power Spectrum
| dc.creator | Miller, Christopher J. | |
| dc.creator | Nichol, Robert C. | |
| dc.creator | Genovese, Christopher | |
| dc.creator | Wasserman, Larry | |
| dc.date | 2001-12-03 | |
| dc.date.accessioned | 2026-07-07T02:01:39Z | |
| dc.date.available | 2026-07-07T02:01:39Z | |
| dc.description | We examine Cosmic Microwave Background (CMB) temperature power spectra from the BOOMERANG, MAXIMA, and DASI experiments. We non-parametrically estimate the true power spectrum with no model assumptions. This is a significant departure from previous research which used either cosmological models or some other parameterized form (e.g. parabolic fits). Our non-parametric estimate is practically indistinguishable from the best fit cosmological model, thus lending independent support to the underlying physics that governs these models. We also generate a confidence set for the non-parametric fit and extract confidence intervals for the numbers, locations, and heights of peaks and the successive peak-to-peak height ratios. At the 95%, 68%, and 40% confidence levels, we find functions that fit the data with one, two, and three peaks respectively (0 <= l <= 1100). Therefore, the current data prefer two peaks at the 1 sigma level. However, we also rule out a constant temperature function at the >8 sigma level. If we assume that there are three peaks in the data, we find their locations to be within l_1 = (118,300), l_2 = (377,650), and l_3 = (597,900). We find the ratio of the first peak-height to the second (Delta T_1)/(Delta T_2)^2= (1.06, 4.27) and the second to the third (Delta T_2)/(Delta T_3)^2= (0.41, 2.5). All measurements are for 95% confidence. If the standard errors on the temperature measurements were reduced to a third of what they are currently, as we expect to be achieved by the MAP and Planck CMB experiments, we could eliminate two-peak models at the 95% confidence limit. The non-parametric methodology discussed in this paper has many astrophysical applications. | |
| dc.description | Uses emulateapj.sty. 4 pages, 1 table, 2 figures. Submitted to ApJ Letters. Our code and best non-parametric fit are available at http://www.picagroup.org | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0112049 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0112049 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/3829 | |
| dc.subject | Astrophysics | |
| dc.title | A Non-parametric Analysis of the CMB Power Spectrum | |
| dc.type | text |