Publications (21)
Orbital Period Increase in ES Ceti
Enrique de Miguel, Joseph Patterson, Jonathan Kemp +5
We report a long-term study of the eclipse times in the 10-minute helium binary ES Ceti. The binary period increases rapidly, with P/P-dot = 6.2x10^6 yr. This is consistent with th…
The Spin-Period History of Intermediate Polars
Joseph Patterson, Enrique de Miguel, Jonathan Kemp +25
We report the detailed history of spin-period changes in five intermediate polars (DQ Herculis, AO Piscium, FO Aquarii, V1223 Sagittarii, and BG Canis Minoris) during the 30-60 yea…
The asynchronous polar V1432 Aquilae and its path back to synchronism
David Boyd, Joseph Patterson, William Allen +23
V1432 Aquilae is the only known eclipsing asynchronous polar. In this respect it is unique and therefore merits our attention. We report the results of a 15-year campaign by the gl…
Pulsations, Boundary Layers, and Period Bounce in the Cataclysmic Variable RE J1255+266
Joseph Patterson, John Thorstensen, Jonathan Kemp
We report time-series photometry of the quiescent optical counterpart of the EUV transient RE J1255+266. The star appears as a DA white dwarf with bright emission lines and a compl…
Orbital Period Changes in WZ Sagittae
Joseph Patterson, Geoffrey Stone, Jonathan Kemp +19
We report a long-term (1961-2017) study of the eclipse times in the dwarf nova WZ Sagittae, in an effort to learn its rate of orbital-period change. Some wiggles with a time scale…
Superhumps in Cataclysmic Binaries. XXV. q_crit, epsilon(q), and Mass-Radius
Joseph Patterson, Jonathan Kemp, David Harvey +17
We report on successes and failures in searching for positive superhumps in cataclysmic variables, and show the superhumping fraction as a function of orbital period. Basically, al…
The Periodic Signals of Nova V1674 Herculis (2021)
Joseph Patterson, Marguerite Epstein-Martin, Josie Enenstein +24
We present time-series photometry during eruption of the extremely fast nova V1674 Herculis (Nova Her 2021). The 2021 light curve showed periodic signals at 0.152921(3) d and 501.4…
Rapid Oscillations in Cataclysmic Variables. XV. HT Camelopardalis (= RX J0757.0+6306)
Jonathan Kemp, Joseph Patterson, John Thorstensen +3
We present photometry and spectroscopy of HT Camelopardalis, a recently discovered X-ray-bright cataclysmic variable. The spectrum shows bright lines of H, He I, and He II, all mov…
XTE J2123-058: A New Neutron Star X-Ray Transient
John A. Tomsick, Jules P. Halpern, Jonathan Kemp +1
We report on optical and RXTE observations of a new high-latitude bursting X-ray transient, XTE J2123-058. We identified the optical counterpart, measured the 5.9573 hr orbital per…
The Death Spiral of T Pyxidis
Joseph Patterson, Arto Oksanen, Berto Monard +12
We report a long campaign to track the 1.8 hr photometric wave in the recurrent nova T Pyxidis, using the global telescope network of the Center for Backyard Astrophysics. During 1…
IM Normae: The Death Spiral of a Cataclysmic Variable?
Joseph Patterson, Jonathan Kemp, Berto Monard +18
We present a study of the orbital light curves of the recurrent nova IM Normae since its 2002 outburst. The broad "eclipses" recur with a 2.46 hour period, which increases on a tim…
Superhumps in Cataclysmic Binaries. XXII. 1RXS J232953.9+062814
David Skillman, Thomas Krajci, Edward Beshore +7
We report photometry of 1RXS J232953.9+062814, a recently discovered dwarf nova with a remarkably short 64.2-minute orbital period. In quiescence, the star's light curve is that of…
Two new accreting, pulsating white dwarfs: SDSS J1457+51 and BW Sculptoris
Helena Uthas, Joseph Patterson, Jonathan Kemp +8
We report the discovery of rapid periodic signals in the light curves of two cataclysmic variables with prominent white-dwarf components in their spectra, SDSS J1457+51 and BW Scul…
1RXS J232953.9+062814: A Dwarf Nova with a 64-minute Orbital Period and a Conspicuous Secondary Star
John R. Thorstensen, William H. Fenton, Joseph O. Patterson +3
We present spectroscopy and time-series photometry of the newly discovered dwarf nova 1RXS J232953.9+062814. Photometry in superoutburst reveals a superhump with a period of 66.06(…
Precise Measures of Orbital Period, Before and After Nova Eruption for QZ Aurigae
Bradley E. Schaefer, David Boyd, Geoffrey C. Clayton +7
For the ordinary classical nova QZ Aurigae (which erupted in 1964), we report 1317 magnitudes from 1912--2016, including four eclipses detected on archival photographic plates from…
BK Lyncis: The Oldest Old Nova?... And a Bellwether for Cataclysmic-Variable Evolution
Joseph Patterson, Helena Uthas, Jonathan Kemp +21
We summarize the results of a 20-year campaign to study the light curves of BK Lyncis, a nova-like star strangely located below the 2-3 hour orbital period gap in the family of cat…
Rapid Oscillations in Cataclysmic Variables. XVI. DW Cancri
Joseph Patterson, John Thorstensen, Tonny Vanmunster +7
We report photometry and spectroscopy of the novalike variable DW Cancri. The spectra show the usual broad H and He emission lines, with an excitation and continuum slope character…
The orbital and superhump periods of the deeply eclipsing dwarf nova SDSS J150240.98+333423.9
Jeremy Shears, Tut Campbell, Jerry Foote +13
During July 2009 we observed the first confirmed superoutburst of the eclipsing dwarf nova SDSS J150240.98+333423.9 using CCD photometry. The outburst amplitude was at least 3.9 ma…
The Rise and Fall of the King: The Correlation between FO Aquarii's Low States and the White Dwarf's Spindown
Colin Littlefield, Peter Garnavich, Mark R. Kennedy +45
The intermediate polar FO Aquarii (FO Aqr) experienced its first-reported low-accretion states in 2016, 2017, and 2018, and using newly available photographic plates, we identify p…
T Pyxidis: Death by a Thousand Novae
Joseph Patterson, Arto Oksanen, Jonathan Kemp +14
We report a 20-year campaign to track the 1.8 hour photometric wave in the recurrent nova T Pyxidis, using the global telescope network of the Center for Backyard Astrophysics. Dur…
Outbursts of EX Hydrae: mass-transfer events or disc instabilities?
Coel Hellier, Jonathan Kemp, T. Naylor +5
We present the 45-yr record of EX Hya's lightcurve and discuss the characteristics of its 15 observed outbursts. We then concentrate on the 1998 outburst, reporting the first outbu…