Zobrazeno 1 - 10
of 297
pro vyhledávání: '"Gray, M D"'
We use 3D computer modelling to investigate the timescales and radiative output from maser flares generated by the impact of shock-waves on astronomical unit-scale clouds in interstellar and star-forming regions, and in circumstellar regions in some
Externí odkaz:
http://arxiv.org/abs/2404.10741
ATOMIUM: Probing the inner wind of evolved O-rich stars with new, highly excited H$_2$O and OH lines
Autor:
Baudry, A., Wong, K. T., Etoka, S., Richards, A. M. S., Muller, H. S. P., Herpin, F., Danilovich, T., Gray, M. D., Wallstrom, S., Gobrecht, D., Khouri, T., Decin, L., Gottlieb, C. A., Menten, K. M., Homan, W., Millar, T. J., Montarges, M., Pimpanuwat, B., Plane, J. M. C., Kervella, P.
Publikováno v:
A&A 674, A125 (2023)
Water and the hydroxyl radical are major constituents of the envelope of O-rich late-type stars. Transitions involving energy levels that are highly excited have been observed in both H$_2$O and OH. These and more recently discovered transitions can
Externí odkaz:
http://arxiv.org/abs/2305.03171
Autor:
Montargès, M., Cannon, E., de Koter, A., Khouri, T., Lagadec, E., Kervella, P., Decin, L., McDonald, I., Homan, W., Waters, L. B. F. M., Sahai, R., Gottlieb, C. A., Malfait, J., Maes, S., Pimpanuwat, B., Jeste, M., Danilovich, T., De Ceuster, F., Van de Sande, M., Gobrecht, D., Wallström, S. H. J., Wong, K. T., Mellah, I. El, Bolte, J., Herpin, F., Richards, A. M. S., Baudry, A., Etoka, S., Gray, M. D., Millar, T. J., Menten, K. M., Müller, H. S. P., Plane, J. M. C., Yates, J., Zijlstra, A.
Publikováno v:
A&A 671, A96 (2023)
Aims. Through the ATOMIUM project, based on an ALMA large program, we aim to present a consistent view of a sample of 17 nearby cool evolved stars (Aymptotic Giant Branch and red supergiant stars). Methods. Here we present VLT/SPHERE-ZIMPOL polarimet
Externí odkaz:
http://arxiv.org/abs/2301.02081
Autor:
Evans, A., Pimpanuwat, B., Richards, A. M. S., Banerjee, D. P. K., Munari, U., Gray, M. D., Kramer, B. Hutawarakorn, Kraus, A.
Publikováno v:
MNRAS, 514, 4894 - 4897 (2022)
There are indications that the third known eruption of the recurrent nova T CrB is imminent, and multi-wavelength observations prior to the eruption are important to characterise the system before it erupts. T CrB is known to display the SiO fundamen
Externí odkaz:
http://arxiv.org/abs/2207.14743
A 3D maser model has been used to perform an inverse problem on the light curves from three high-amplitude maser flares, selected on the basis of contemporaneous infra-red observations. Plots derived from the model recover the size of the maser cloud
Externí odkaz:
http://arxiv.org/abs/2006.13124
We simulate maser flares by varying either the pump rate or the background level of radiation in a 3D model of a maser cloud. We investigate the effect of different cloud shapes, saturation levels and viewpoints. Results are considered for clouds wit
Externí odkaz:
http://arxiv.org/abs/2002.04490
We investigated, through numerical models, the flaring variability that may arise from the rotation of maser clouds of approximately spheroidal geometry, ranging from strongly oblate to strongly prolate examples. Inversion solutions were obtained for
Externí odkaz:
http://arxiv.org/abs/1904.10347
We set out the theory and discretization scheme for a new finite-element computer code, written specifically for the simulation of maser sources. The code was used to compute fractional inversions at each node of a 3-D domain for a range of optical t
Externí odkaz:
http://arxiv.org/abs/1803.01625
Autor:
Sobolev, A. M., Moran, J. M., Gray, M. D., Alakoz, A., Imai, H., Baan, W. A., Tolmachev, A. M., Samodurov, V. A., Ladeyshchikov, D. A.
We present the first VLBI observations of a Galactic water maser (in Chepeus A) made with a very long baseline interferometric array involving the RadioAstron Earth-orbiting satellite station as one of its elements. We detected two distinct component
Externí odkaz:
http://arxiv.org/abs/1802.06756
Autor:
Baudry, A., Humphreys, E. M. L., Herpin, F., Torstensson, K., Vlemmings, W. H. T., Richards, A. M. S., Gray, M. D., De Breuck, C., Olberg, M.
Publikováno v:
A&A 609, A25 (2018)
Several rotational transitions of water have been identified toward evolved stars in the ground vibrational state as well as in the first excited state of the bending mode. In the latter vibrational state of water, the 658 GHz J = 1_1,0-1_0,1 rotatio
Externí odkaz:
http://arxiv.org/abs/1711.02350