This paper describes the overview of the FLASHING (Finest Legacy Acquisitions of SiO-/ H2O-maser Ignitions by the Nobeyama Generation) project promoted using the 45 m telescope of Nobeyama Radio Observatory, which aims to intensively monitor H2O (22 GHz) and SiO (43 GHz) masers associated with so-called "water fountain" sources. Here we show scientific results on the basis of the data taken in for the first five seasons of FLASHING, from 2018 December to 2023 April). We have found the evolution of the H2O maser spectra, such as new spectral components breaking the record of the jet's top speed and/or systematic velocity drifts in the spectrum indicating acceleration or deceleration of the maser gas clumps. For the 43 GHz SiO maser emission, we have found its new detection in a source while its permanent disappearance in other source. Our finding may imply that the jets from these water fountains can be accelerated or decelerated, and show how cicumstellar envelopes have been destroyed.
Cite
@article{arxiv.2309.00657,
title = {FLASHING: Project Overview},
author = {Hiroshi Imai and Yuhki Hamae and Kei Amada and Keisuke Nakashima and Ka-Yiu Shum and Rina Kasai and Jose F. Gomez and Lucero Uscanga and Daniel Tafoya and Gabor Orosz and Ross A. Burns},
journal= {arXiv preprint arXiv:2309.00657},
year = {2023}
}
Comments
31 pages, 22 figures, to be published in the Publications of the Astronomical Society of Japan