CONSTRAINT ON A COSMOLOGICAL VARIATION IN THE PROTON-TO-ELECTRON MASS RATIO FROM ELECTRONIC CO ABSORPTION
| Autor: | M. Niu, Michael T. Murphy, Wim Ubachs, Edcel J. Salumbides, M. Daprà |
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| Přispěvatelé: | Atoms, Molecules, Lasers, LaserLaB - Physics of Light, Physics and Astronomy |
| Rok vydání: | 2016 |
| Předmět: |
Cosmology and Nongalactic Astrophysics (astro-ph.CO)
FOS: Physical sciences Astrophysics::Cosmology and Extragalactic Astrophysics Electron 01 natural sciences 0103 physical sciences Absorption (logic) Sensitivity (control systems) Physics::Chemical Physics 010306 general physics 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics Physics Order (ring theory) Astronomy and Astrophysics Quasar Mass ratio Proton-to-electron mass ratio Astrophysics - Astrophysics of Galaxies Redshift Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) Astrophysics::Earth and Planetary Astrophysics Atomic physics SDG 6 - Clean Water and Sanitation Astrophysics - Cosmology and Nongalactic Astrophysics |
| Zdroj: | Astrophysical Journal, 826(2):192. IOP Publishing Ltd. Dapra, M, Niu, M, Salumbides, E J, Murphy, M T & Ubachs, W M G 2016, ' constraint on a cosmological variation in the proton-to-electron mass ratio from electronic co absorption ', Astrophysical Journal, vol. 826, no. 2, 192 . https://doi.org/10.3847/0004-637X/826/2/192 The Astrophysical Journal |
| ISSN: | 1538-4357 0004-637X 0004-6361 0067-0049 0293-9398 |
| DOI: | 10.3847/0004-637x/826/2/192 |
| Popis: | Carbon monoxide (CO) absorption in the sub-damped Lyman-$\alpha$ absorber at redshift $z_{abs} \simeq 2.69$, toward the background quasar SDSS J123714.60+064759.5 (J1237+0647), was investigated for the first time in order to search for a possible variation of the proton-to-electron mass ratio, $\mu$, over a cosmological time-scale. The observations were performed with the Very Large Telescope/Ultraviolet and Visual Echelle Spectrograph with a signal-to-noise ratio of 40 per 2.5 kms$^{-1}$ per pixel at $\sim 5000$ \AA. Thirteen CO vibrational bands in this absorber are detected: the A$^{1}\Pi$ - X$^{1}\Sigma^{+}$ ($\nu'$,0) for $\nu' = 0 - 8$, B$^{1}\Sigma^{+}$ - X$^{1}\Sigma^{+}$ (0,0), C$^{1}\Sigma^{+}$ - X$^{1}\Sigma^{+}$ (0,0), and E$^{1}\Pi$ - X$^{1}\Sigma^{+}$ (0,0) singlet-singlet bands and the d$^{3}\Delta$ - X$^{1}\Sigma^{+}$ (5,0) singlet-triplet band. An updated database including the most precise molecular inputs needed for a $\mu$-variation analysis is presented for rotational levels $J = 0 - 5$, consisting of transition wavelengths, oscillator strengths, natural lifetime damping parameters, and sensitivity coefficients to a variation of the proton-to-electron mass ratio. A comprehensive fitting method was used to fit all the CO bands at once and an independent constraint of $\Delta\mu/\mu = (0.7 \pm 1.6_{stat} \pm 0.5_{syst}) \times 10^{-5}$ was derived from CO only. A combined analysis using both molecular hydrogen and CO in the same J1237+0647 absorber returned a final constraint on the relative variation of $\Delta\mu/\mu = (-5.6 \pm 5.6_{stat} \pm 3.1_{syst}) \times 10^{-6}$, which is consistent with no variation over a look-back time of $\sim 11.4$ Gyrs. Comment: 44 pages, 9 figures, accepted for publication in the Astrophysical Journal |
| Databáze: | OpenAIRE |
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