Zobrazeno 1 - 10
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pro vyhledávání: '"Schaefer, Bradley E"'
Autor:
Schaefer, Bradley E.
V2487 Ophiuchi (V2487 Oph) is a recurrent nova with classical nova eruptions in 1900 and 1998, and it is also the most extreme known superflare star. These superflares are roughly-hour-long flares with amplitudes and optical energies reaching up to 1
Externí odkaz:
http://arxiv.org/abs/2405.01210
Autor:
Schaefer, Bradley E.
The evolution of Cataclysmic Variables (CVs) is driven by period-changes ($\dot{P}$), for which the long-venerable consensus is the Magnetic Braking Model (MBM). The MBM has its only distinctive assumption being a power-law `recipe' describing the an
Externí odkaz:
http://arxiv.org/abs/2404.12525
Autor:
Schaefer, Bradley E.
R Coronae Borealis stars (RCBs) are cool supergiants that display non-periodic deep dips in brightness. Recently, a group of `Hot RCB stars` has been discovered to be fast evolving across the HR diagram, as these stars leave the RCB region, with brig
Externí odkaz:
http://arxiv.org/abs/2312.01843
Autor:
Schaefer, Bradley E.
The famous recurrent nova (RN) T Coronae Borealis (T CrB) has had observed eruptions peaking at a visual magnitude of 2.0 in the years 1866 and 1946, while a third eruption is now expected for the year 2024.4+-0.3. Each RN has very similar light curv
Externí odkaz:
http://arxiv.org/abs/2308.13668
Autor:
Schaefer, Bradley E.
The evolution of novae and Cataclysmic Variables (CVs) is driven by changes in the binary orbital periods. In a direct and critical test for various evolution models and their physical mechanisms, I measure the sudden changes in the period ($\Delta P
Externí odkaz:
http://arxiv.org/abs/2307.13804
Autor:
Schaefer, Bradley E.
T CrB is one of the most-famous and brightest novae known, and is a recurrent nova with prior eruptions in 1866 and 1946 that peak at $V$=2.0. I have constructed light curves spanning 1842--2022 with 213,730 magnitudes, where the $B$ and $V$ magnitud
Externí odkaz:
http://arxiv.org/abs/2303.04933
A newly recognized young Galactic SN remnant, Pa 30 (G123.1+4.6), centered on a hot central star with a ~16,000 km/s wind velocity has recently been proposed to be the result of a double-degenerate merger leading to a SN Iax event associated with the
Externí odkaz:
http://arxiv.org/abs/2301.04809
Autor:
Schaefer, Bradley E.
In 1181 AD, Chinese and Japanese observers reported an unmoving bright `Guest Star' in the constellation Chuanshe, visible for 185 days. In 2013, D. Patchick discovered what turned out to be a unique nebula surrounding a unique star, with the structu
Externí odkaz:
http://arxiv.org/abs/2301.04807
KT Eridani was a very fast nova in 2009 peaking at V=5.42 mag. We marshal large data sets of photometry to finally work out the nature of KT Eri. From the TESS light curve, as confirmed with our radial velocity curve, we find an orbital period of 2.6
Externí odkaz:
http://arxiv.org/abs/2210.10448
Autor:
Schaefer, Bradley E.
I derive the overall best distances for all 402 known galactic novae, and I collect their many properties. The centrepiece is the 74 novae with accurate parallaxes from the new Gaia data release. For the needed priors, I have collected 171 distances
Externí odkaz:
http://arxiv.org/abs/2210.03181