Zobrazeno 1 - 10
of 111
pro vyhledávání: '"Agafonova, A. I."'
Autor:
Agafonova, I. I., Bayandina, O. S., Gong, Y., Henkel, C., Kim, Kee-Tae, Kozlov, M. G., Lankhaar, B., Levshakov, S. A., Menten, K. M., Ubachs, W., Val'tts, I. E., Yang, W.
We present results on simultaneous observations of Class~I methanol masers at 25, 36, and 44 GHz towards 22 Galactic targets carried out with the Effelsberg 100-m telescope. The study investigates relations between the hyperfine (HF) structure of the
Externí odkaz:
http://arxiv.org/abs/2407.11657
Autor:
Levshakov, S. A., Agafonova, I. I., Henkel, C., Kim, Kee-Tae, Kozlov, M. G., Lankhaar, B., Yang, W.
We estimate limits on non-universal coupling of hypothetical hidden fields to standard matter by evaluating the fractional changes in the electron-to-proton mass ratio, mu = m_e/m_p, based on observations of ClassI methanol masers distributed in the
Externí odkaz:
http://arxiv.org/abs/2112.14560
Far infrared fine-structure transitions of CI and CII and rotational transitions of CO are used to probe hypothetical variations of the electron-to-proton mass ratio mu = m_e/m_p at the epoch of reionization (z > 6). A constraint on Delta mu/mu = (mu
Externí odkaz:
http://arxiv.org/abs/2008.11143
Autor:
Levshakov, S. A., Ng, K. -W., Henkel, C., Mookerjea, B., Agafonova, I. I., Liu, S. -Y., Wang, W. -H.
Non-standard fields are assumed to be responsible for phenomena attributed to dark energy and dark matter. Being coupled to ordinary matter, these fields modify the masses and/or charges of the elementary particles, thereby violating the Weak Equival
Externí odkaz:
http://arxiv.org/abs/1906.03682
Autor:
Agafonova, I I, Bayandina, O S, Gong, Y, Henkel, C, Kim, Kee-Tae, Kozlov, M G, Lankhaar, B, Levshakov, S A, Menten, K M, Ubachs, W, Val'tts, I E, Yang, W
Publikováno v:
Monthly Notices of the Royal Astronomical Society; Sep2024, Vol. 533 Issue 2, p1714-1732, 19p
Autor:
Bonifacio, P., Rahmani, H., Whitmore, J. B., Wendt, M., Centurion, M., Molaro, P., Srianand, R., Murphy, M. T., Petitjean, P., Agafonova, I. I., D'Odorico, S., Evans, T. M., Levshakov, S. A., Lopez, S., Martins, C. J. A. P., Reimers, D., Vladilo, G.
Absorption-line systems detected in high resolution quasar spectra can be used to compare the value of dimensionless fundamental constants such as the fine-structure constant, alpha, and the proton-to-electron mass ratio, mu = m_p/m_e, as measured in
Externí odkaz:
http://arxiv.org/abs/1310.6280
Autor:
Molaro, P., Centurion, M., Whitmore, J. B., Evans, T. M., Murphy, M. T., Agafonova, I. I., Bonifacio, P., D'Odorico, S., Levshakov, S. A., Lopez, S., Martins, C. J. A. P., Petitjean, P., Rahmani, H., Reimers, D., Srianand, R., Vladilo, G., Wendt, M.
Absorption line systems detected in quasar spectra can be used to compare the value of the fine-structure constant, {\alpha}, measured today on Earth with its value in distant galaxies. In recent years, some evidence has emerged of small temporal and
Externí odkaz:
http://arxiv.org/abs/1305.1884
(Abridged) Aims. To probe the spectral energy distribution (SED) of the ionizing background radiation at z ~ 2 and to specify the sources contributing to the intergalactic radiation field. Methods. The spectrum of a bright quasar HS1103+6416 (zem = 2
Externí odkaz:
http://arxiv.org/abs/1303.1000
Publikováno v:
Astron. Astrophys., 2012, 540, L9
Aims. We constrain a hypothetical variation in the fundamental physical constants over the course of cosmic time. Methods. We use unique observations of the CO(7-6) rotational line and the [CI] 3P_2 - 3P_1 fine-structure line towards a lensed galaxy
Externí odkaz:
http://arxiv.org/abs/1203.3649
(Abridged) We use a high-resolution spectrum of the quasar HE0001-2340 observed with the UVES/VLT to measure Mg isotope abundances in the intervening absorption-line systems at high redshifts. Line profiles are prepared accounting for possible shifts
Externí odkaz:
http://arxiv.org/abs/1102.2967