Results 41 to 50 of about 6,211,798 (244)

A catalogue of white-light flares observed by Yohkoh [PDF]

, 2003
The aspect camera of the Soft X-ray Telescope (SXT) on Yohkoh provided the first systematic survey of white-light flares from an observatory in space. The observations were made in the Fraunhofer g-band at a pixel size of 2.46 arcsec and a typical sample
H. S. Hudson, N. V. Nitta, van Driel-Gesztelyi, L, Matthews, SA, L. van Driel-Gesztelyi, Hudson, HS, Nitta, NV, S. A. Matthews   +7 more
core   +1 more source

X-ray flares from Sgr A*: Star-disk interactions?

, 2004
Sgr A *, the putative black hole in our Galactic Center (GC), is extraordinary dim in all frequencies. Apparently the black hole is unable to accrete at the Bondi accretion rate for some reason. Another mystery of Sgr A * is the recently discovered large
J. Cuadra (7212728), S. Nayakshin (7603412), R. Sunyaev (7603820)   +2 more
core   +5 more sources

‘Failed’ tidal disruption events and X-ray flares from the Galactic Centre [PDF]

Monthly notices of the Royal Astronomical Society, 2019
The process of tidal disruption of stars by a supermassive black hole (SMBH) provides luminous UV and soft X-ray flares with peak luminosities of $\approx 10^{46}$ ergs/sec and duration of a few months.
A. Sacchi, G. Lodato
semanticscholar   +1 more source

Latest results on Jovian disk X-rays from XMM-Newton [PDF]

, 2007
We present the results of a spectral study of the soft X-ray emission (0.2–2.5 keV) from low-latitude (‘disk’) regions of Jupiter. The data were obtained during two observing campaigns with XMM-Newton in April and November 2003.
Waite Jr., J. H., Gladstone, G.R., Rodriguez, P., Branduardi-Raymont, G., Cravens, T.E., Gladstone, G. R., Ramsay, G., Soria, R., Elsner, R. F., Waite, J.H., Bhardwaj, A., Elsner, R.F., Cravens, T. E.   +12 more
core   +1 more source

Particle acceleration in the presence of weak turbulence at an X-type neutral point [PDF]

, 2012
We simulate the likely noisy situation near a reconnection region by superposing many 2D linear reconnection eigenmodes. The superposition of modes on the steady state X-type magnetic field creates multiple X- and O-type neutral points close to the ...
Petkaki, P., MacKinnon, A.L., Burge, C. A., MacKinnon, A. L., Burge, C.A.   +4 more
core   +1 more source

Balmer and Soft X-ray Emission from Solar and Stellar Flares [PDF]

Symposium - International Astronomical Union, 1990
Integrated soft X-ray (8-12A) fluxes for solar flares have been scaled to the equivalent EXOSAT fluxes using spectra obtained from a variety of rocket-based experiments. The data show good agreement with the soft X-ray - Hγ correlation established by Butler et al. (1988) for stellar flares and confirm the basic similarity, in this respect, of flares on
openaire   +1 more source

What can be learnt from full disk X-ray observations of stellar flares? [PDF]

Symposium - International Astronomical Union, 1987
The Einstein Observatory demonstrated the existence of hot envelopes, i.e., stellar coronae, around most classes of normal stars (Vaiana et al. 1981). The coronae of late type stars of spectral type F through M are generally thought to be solar-like, i.e., structured and organised by the magnetic field topology and heated by some process(es) involving ...
J. H. M. M. Schmitt, H. Fink, F. R. Harnden   +2 more
openaire   +1 more source

The nature of the X-ray transient MAXI J0556−332 [PDF]

, 2012
Phase-resolved spectroscopy of the newly discovered X-ray transient MAXIJ0556-332 has revealed the presence of narrow emission lines in the Bowen region that most likely arise on the surface of the mass donor star in this low-mass X-ray binary.
Charles, PA, Cornelisse, R., Steeghs, D., O'Brien, Kieran, Munoz-Darias, T, Israel, G., Israel, G, Charles, P. A., Steeghs, D, Casares, J, Torres, M. A. P., Muñoz-Darias, T., Casares, J., Stella, L, Campana, S, Torres, M.A.P., Torres, MAP, Campana, S., Charles, P.A., Stella, L., D'Avanzo, P, O'Brien, K, Cornelisse, R, Israel, G. L., O'Brien, K., D'Avanzo, P.   +25 more
core   +1 more source

The Giant Flares of the Microquasar Cygnus X-3: X-Rays States and Jets

Galaxies, 2017
We report on two giant radio flares of the X-ray binary microquasar Cyg X-3, consisting of a Wolf–Rayet star and probably a black hole. The first flare occurred on 13 September 2016, 2000 days after a previous giant flare in February 2011, as the RATAN ...
Sergei Trushkin, Michael McCollough, Nikolaj Nizhelskij, Peter Tsybulev   +3 more
doaj   +1 more source

The solar—stellar connection: the relationship between flaring rates, flare power and quiescent X-ray background [PDF]

International Astronomical Union Colloquium, 1989
The nature of flare activity on dMc stars (red dwarfs with strong chromospheric IIα emission lines) has been the subject of many studies. Some years ago Lacy et al. (1976) demonstrated a relationship (see also Doyle et al., 1986) between mean flare power and quiescent luminosity, in the photometric U-band.
Richard A. Harrison, Gillian Pearce, Andrew Skumanich   +2 more
openaire   +1 more source