Zobrazeno 1 - 10
of 250
pro vyhledávání: '"Levshakov, S A"'
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
Numerical calculations of the sensitivity coefficients, Q_mu, of microwave molecular transitions in the ground torsion-rotation state of deuterated methanol (CH3OD, CD3OH, and CD3OD) to small variations in the fundamental physical constant mu = me/mp
Externí odkaz:
http://arxiv.org/abs/2406.10299
Autor:
Vorotyntseva, J. S., Levshakov, S. A.
We report on the using of torsion-rotational transitions in the CH3OH and (13)CH3OH molecules to evaluate possible variations of the physical constant mu=m_e/m_p - the electron-to-proton mass ratio - from spectral observations of emission lines detec
Externí odkaz:
http://arxiv.org/abs/2405.04542
Autor:
Vorotyntseva, J. S., Levshakov, S. A.
High-dispersion (channel width 0.015 km s^-1) laboratory spectroscopy of the torsion-rotation lines J_2 - J_1 (J = 2 - 6) in the ground torsional state (vt = 0) of the E-type methanol demonstrates multicomponent hyperfine splitting patterns at 25 GHz
Externí odkaz:
http://arxiv.org/abs/2310.08231
We present results on numerical calculations of the sensitivity coefficients, Qmu, of microwave molecular transitions in (13C)H3OH and CH3(18O)H to the hypothetical variation in the fundamental physical constant mu - the electron-to-proton mass ratio
Externí odkaz:
http://arxiv.org/abs/2310.04485
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
Autor:
Tang, X. D., Henkel, C., Menten, K. M., Gong, Y., Chen, C. -H. R., Li, D. L., Lee, M. -Y., Mangum, J. G., Ao, Y. P., Mühle, S., Aalto, S., García-Burillo, S., Martín, S., Viti, S., Muller, S., Costagliola, F., Asiri, H., Levshakov, S. A., Spaans, M., Ott, J., Impellizzeri, C. M. V., Fukui, Y., He, Y. X., Esimbek, J., Zhou, J. J., Zheng, X. W., Zhao, X., Li, J. S.
Publikováno v:
A&A 655, A12 (2021)
We mapped the kinetic temperature structure of two massive star-forming regions, N113 and N159W, in the Large Magellanic Cloud (LMC). We have used $\sim$1\hbox{$\,.\!\!^{\prime\prime}$}6\,($\sim$0.4\,pc) resolution measurements of the para-H$_2$CO\,$
Externí odkaz:
http://arxiv.org/abs/2108.10519
Autor:
Levshakov, S. A.
Spacetime variations of physical constants can be associated with the existence of Higgs-like scalar field(s) that couple non-universally to the baryonic matter. Recent results of astronomical spectral measurements of the fractional changes in the el
Externí odkaz:
http://arxiv.org/abs/2010.07134
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:
Humire, P., Henkel, C., Gong, Y., Leurini, S., Mauersberger, R., Levshakov, S. A., Winkel, B., Tarchi, A., Castangia, P., Malawi, A., Asiri, H., Ellingsen, S. P., McCarthy, T. P., Chen, X., Tang, X.
Publikováno v:
A&A 633, A106 (2020)
Methanol (CH3OH) is one of the most abundant interstellar molecules, offering a vast number of transitions to be studied, including many maser lines. While the strongest Galactic CH3OH lines, the so-called class II masers, show no indications for the
Externí odkaz:
http://arxiv.org/abs/1911.06776