Zobrazeno 1 - 10
of 630
pro vyhledávání: '"Keenan, F. P."'
We present results from a pilot study, using a laser-produced plasma, to identify new lines in the 350 to 1000 nm spectral region for the r-process element gold (Au), of relevance to studies of neutron star mergers. This was achieved via optical-IR s
Externí odkaz:
http://arxiv.org/abs/2407.15072
Autor:
Riley, D., Singh, R. L., White, S, Charlwood, M., Bailie, D., Hyland, C., Audet, T., Sarri, G., Kettle, B., Gribakin, G., Rose, S. J., Hill, E. G., Ferland, G. J., Williams, R. J. R., Keenan, F. P.
We describe laboratory experiments to generate X-ray photoionized plasmas of relevance to accretion-powered X-ray sources such as neutron star binaries and quasars, with significant improvements over previous work. A key quantity is referenced, namel
Externí odkaz:
http://arxiv.org/abs/2309.07267
Autor:
Singh, R. L., White, S., Charlwood, M., Keenan, F. P., Hyland, C., Bailie, D., Audet, T., Sarri, G., Rose, S. J., Morton, J., Baird, C., Spindloe, C., Riley, D.
We have employed the VULCAN laser facility to generate a laser plasma X-ray source for use in photoionisation experiments. A nanosecond laser pulse with an intensity of order ${10}^{15}$ W{cm}$^{-2}$ was used to irradiate thin Ag or Sn foil targets c
Externí odkaz:
http://arxiv.org/abs/2204.11129
Autor:
Bate, W., Jess, D. B., Nakariakov, V. M., Grant, S. D. T., Jafarzadeh, S., Stangalini, M., Keys, P. H., Christian, D. J., Keenan, F. P.
Using high cadence observations from the Hydrogen-alpha Rapid Dynamics camera imaging system on the Dunn Solar Telescope, we present an investigation of the statistical properties of transverse oscillations in spicules captured above the solar limb.
Externí odkaz:
http://arxiv.org/abs/2203.04997
Observations of the dynamics of solar coronal structures are necessary to investigate space weather phenomena and global heating of the corona. The profiles of high temperature lines emitted by the hot plasma are usually integrated by narrow band fil
Externí odkaz:
http://arxiv.org/abs/2110.01645
The Multichannel Subtractive Double Pass (MSDP) is an imaging spectroscopy technique, which allows observations of spectral line profiles over a 2D field of view with high spatial and temporal resolution. It has been intensively used since 1977 on va
Externí odkaz:
http://arxiv.org/abs/2101.03918
Autor:
Sarkar, A., Ferland, G. J., Chatzikos, M., Guzmán, F., van Hoof, P. A. M., Smyth, R. T., Ramsbottom, C. A., Keenan, F. P., Ballance, C. P.
Understanding the Fe II emission from Active Galactic Nuclei (AGN) has been a grand challenge for many decades. The rewards from understanding the AGN spectra would be immense, involving both quasar classification schemes such as "Eigenvector 1" and
Externí odkaz:
http://arxiv.org/abs/2011.09007
Autor:
Rudawy, P., Radziszewski, K., Berlicki, A., Phillips, K. J. H., Jess, D. B., Keys, P. H., Keenan, F. P.
We report on a search for short-period intensity variations in the green-line FeXIV 530.3 nm emission from the solar corona during the 21 August 2017 total eclipse viewed from Idaho in the United States. Our experiment was performed with a much more
Externí odkaz:
http://arxiv.org/abs/1903.06076
Autor:
White, S, Irwin, R, Warwick, R, Gribakin, G, Sarri, G, Keenan, F P, Riley, D, Rose, S J, Hill, E G, Ferland, G J, Han, B, Wang, F, Zhao, G
In this paper we report the experimental implementation of a theoretically-proposed technique for creating a photoionized plasma in the laboratory using X-ray line radiation. Using a Sn laser-plasma to irradiate an Ar gas target, the photoionization
Externí odkaz:
http://arxiv.org/abs/1805.05767
Solar spectra of ultraviolet bursts and flare ribbons from the Interface Region Imaging Spectrograph (IRIS) have suggested high electron densities of $>10^{12}$ cm$^{-3}$ at transition region temperatures of 0.1 MK, based on large intensity ratios of
Externí odkaz:
http://arxiv.org/abs/1803.01721