Publications (60)
The 2008 outburst of the cataclysmic variable V358 Lyrae
Jeremy Shears, David Boyd, Tut Campbell +7
We report photometry of V358 Lyr during its 2008 November outburst, the first confirmed outburst since 1965. At its brightest the star was V=15.9 and the outburst amplitude was at…
Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. III: The Third Year (2010--2011)
Taichi Kato, Hiroyuki Maehara, Ian Miller +75
Continuing the project described by Kato et al. (2009, PASJ 61, S395, arXiv:0905.1757), we collected times of superhump maxima for 51 SU UMa-type dwarf novae mainly observed during…
Analysis of the first confirmed superoutburst of V337 Cygni in 2006 May
David Boyd, Tom Krajci, Jeremy Shears +1
During 2006 May the first confirmed superoutburst of the dwarf nova V337 Cygni was observed using unfiltered CCD photometry. The outburst reached a peak magnitude of 15.2 on May 22…
Superhump periods in the UGSU-type dwarf nova SDSSp J082409.73+493124.4
David Boyd, Jeremy Shears, Robert Koff
We present observations and analysis of the first reported superoutburst of the dwarf nova SDSSp J082409.73+493124.4 during February/March 2007. From a maximum observed magnitude o…
Z Cam Stars in the Twenty-First Century
Mike Simonsen, David Boyd, Bill Goff +12
Z Cam stars are a small subset of dwarf novae that exhibit standstills in their light curves. Most modern literature and catalogs of cataclysmic variables quote the number of known…
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…
Spectroscopic and photometric study of the Mira stars SU Camelopardalis and RY Cephei
David Boyd
Miras are fascinating stars. A kappa-mechanism in their atmosphere drives pulsations which produce changes in their photometric brightness, apparent spectral type and effective tem…
CSS090530:144011+494734: a new SU UMa-type dwarf nova in Bootes
David Boyd, Nick Dunckel, Jerry Foote +1
We report photometry and analysis of a previously unknown SU UMa-type dwarf nova in Bootes detected in outburst by the Catalina Real-time Transient Survey on 2009 May 30 with the d…
Brief outbursts in the dwarf nova V1316 Cygni
Jeremy Shears, David Boyd, Gary Poyner
Several brief outbursts were detected in the dwarf nova V1316 Cyg during 2005. These events have an average amplitude of 1.4 magnitude and a duration of <1 to 2 days. Whilst no out…
Superoutbursts of the SU UMa-type dwarf nova CP Draconis
Jeremy Shears, David Boyd, Denis Buczynski +8
Analysis of observations of the SU UMa-type dwarf nova, CP Dra, between February 2001 and April 2009 has revealed 15 outbursts, at least eight of which were superoutbursts. The sup…
Spectroscopic study of five Mira stars
David Boyd
Mira stars are popular with amateur astronomers because they are generally bright and their pulsations produce large changes in brightness. This also means they are eminently suita…
Spectroscopic Analysis of the 2025 Eclipse of the Symbiotic Binary V1413 Aquilae
David Boyd, James Foster, Forrest Sims +12
We report on a coordinated campaign by amateur astronomers using a combination of high and low resolution spectroscopy to observe the 2025 eclipse of the symbiotic binary V1413 Aql…
TESS photometry of the nova eruption in V606 Vul: asymmetric photosphere and multiple ejections?
Kirill V. Sokolovsky, Elias Aydi, Konstantin Malanchev +70
Lightcurves of many classical novae deviate from the canonical "fast rise - smooth decline" pattern and display complex variability behavior. We present the first TESS-space-photom…
Spectroscopic observations of the bright RV Tauri variable R Scuti
David Boyd
A series of spectra of the RV Tauri star R Scuti taken as it rose from a deep minimum to a bright maximum during 2013 October and November reveals major changes taking place in the…
Outburst characteristics of the dwarf nova V452 Cassiopeiae
Jeremy Shears, Christopher Lloyd, David Boyd +3
V452 Cas was thought to have rare outbursts, but monitoring from 2005 to 2008 has shown that the outburst interval is about one month and is weakly periodic. Observations of seven…
ASAS J071404+7004.3 -- a close, bright nova-like cataclysmic variable with gusty winds
keith Inight, Boris Gaensicke, Dominic Blondel +11
Despite being bright () and nearby ( pc) ASAS J071404+7004.3 has only recently been identified as a nova-like cataclysmic variable. We present time-resolved optical sp…
Spectroscopic and Photometric Study of the Asymptotic Giant Branch Star T Cephei
David Boyd
Spectroscopy and photometry of the Asymptotic Giant Branch star T Cephei were recorded concurrently on 36 nights during its 387 day pulsation cycle in 2022. Photometry was used to…
A Dragon's Flame of Many Colours: Multi-wavelength Observations of Flares from the Active M Binary CR Draconis
James A. G. Jackman, Evgenya L. Shkolnik, R. O. Parke Loyd +9
We present the results of a multi-wavelength Pro-Am campaign to study the behaviour of flares from the active M1.5V star binary CR Draconis. CR Dra was observed with TESS 20-s phot…
Photometry and spectroscopy of a deep Algol-like minimum of WW Vul in 2016
David Boyd
We report analysis of photometry and spectroscopy of a deep Algol-like minimum of the pre-main-sequence star WW Vul in July and August 2016. This revealed substantial reddening due…
Periodic Variations in the Residual Eclipse Flux and Eclipse Timings of Asynchronous Polar V1432 Aql: Evidence of a Shifting Threading Region
Colin Littlefield, Koji Mukai, Ryan Cain +8
We report the results of a twenty-eight-month photometric campaign studying V1432 Aql, the only known eclipsing, asynchronous polar. Our data show that both the residual eclipse fl…
VSX J003909.7+611233: a new Slowly Pulsating B star (SPB) in Cassiopeia?
David Boyd, Christopher Lloyd, Pierre dePonthiere +5
We report the discovery of a new 13th magnitude variable in Cassiopeia close to the variable KP Cas. Analysis of 6 days of intensive photometry shows a regular, near sinusoidal mod…
Investigating the low-flux states in six Intermediate Polars
Ava E. Covington, Aarran W. Shaw, Koji Mukai +30
We present optical photometry of six intermediate polars that exhibit transitions to a low-flux state. For four of these systems, DW Cnc, V515 And, V1223 Sgr and RX J2133.7+5107, w…
The 2008 February superoutburst of V452 Cas
Christopher Lloyd, Roger Pickard, Jeremy Shears +3
Observations of the 2008 February outburst of V452 Cas show that the profile, duration and magnitude at maximum were very similar to the previous superoutburst in 2007 September. L…
Measuring the period of the delta Scuti variable U1425-01208594 in Cassiopeia
Jeremy Shears, David Boyd, Steve Brady +2
The variability of U1425-01208594 was recently discovered by Schmidtobreick et al, who suggested that it is a member of the delta Scuti family of pulsating stars. Photometry conduc…
Long-term Study of Changes in the Orbital Periods of 18 Eclipsing SW Sextantis Stars
David Boyd
SW Sex stars are an informal sub-class of eclipsing nova-like cataclysmic variables. We report 934 new eclipse times measured over the past 17 years for HS 0728+6738 (V482 Cam), SW…
The outburst of V713 Cephei in August 2009
David Boyd, Denis Denisenko, Robert Koff +2
During the outburst of V713 Cephei in August 2009 the times of 8 eclipses were measured and these, together with 5 eclipse timings obtained during quiescence in August 2007, provid…
Combined Spectroscopic and Photometric Analysis of Flares in the Dwarf M Star EV Lacertae
David Boyd, Robert Buchheim, Sean Curry +6
We report results of an observing campaign to study the dwarf M flare star EV Lacertae. Between October 2021 and January 2022 we obtained concurrent B band photometry and low resol…
Photometry and astrometry of SS Leo Minoris during the 2006 October superoutburst
Jeremy Shears, David Boyd, Tom Krajci +3
We report unfiltered CCD observations of the first confirmed superoutburst of the SU UMa-type dwarf nova SS LMi in October 2006. From a quiescent magnitude of around 21.7 it rose t…
Measurement of the orbital and superhump periods of the eclipsing cataclysmic variable SDSS J170213.26+322954.1
David Boyd, Arto Oksanen, Arne Henden
The orbital period of the eclipsing cataclysmic variable SDSS J170213.26+322954.1 has been measured as 0.10008215+/-0.00000001d using observations of eclipses during the first reco…
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…
Photometric and spectroscopic observations of the 2014 eclipse of the complex binary EE Cephei
David Boyd
We report photometric and spectroscopic observations of the 2014 eclipse of EE Cep. This proved to be one of the shallower eclipses on record rather than one of the deepest as pred…
Spectroscopic and Photometric Study of the S-type Mira V667 Cassiopeiae and the Carbon Star OR Cephei
David Boyd
We report on spectroscopic and photometric observations of the S-type Mira V667 Cas and the carbon star Mira OR Cep recorded during one pulsation cycle of each star in 2022. Spectr…
Photometry and spectrophotometry of the Herbig Ae star RR Tauri
David Boyd
Multicolour broadband photometry and flux calibrated low resolution spectroscopy between 2014 and 2018 are used to investigate the behaviour of the highly variable Herbig Ae star R…
Detection and measurement in the V-band of the white dwarf spin period in the January 2004 outburst of DO (YY) Draconis
David Boyd
A modulation in the V-band with period 527.84+/-1.81 sec and amplitude 0.023 magnitude, attributable to the spin of the magnetic white dwarf primary star, has been detected in 7.5…
HD 5501: A Rapidly Evolving Interacting Eclipsing Binary with a Variable Light Curve and H Emission
Richard O. Gray, Christopher. J. Corbally, Sean Curry +19
HD~5501, a hitherto little studied eclipsing binary with an early A-type primary, has been caught in a short-lived, astrophysically interesting phase of its binary evolution. Recen…
Discovery of a Very Bright, Nearby Gravitational Microlensing Event
B. Scott Gaudi, Joseph Patterson, David S. Spiegel +18
We report the serendipitous detection of a very bright, very nearby microlensing event. In late October 2006, an otherwise unremarkable A0 star at a distance ~1 kpc (GSC 3656-1328)…
Photometric and spectroscopic observations of the outburst of the symbiotic star AG Draconis between March and June 2016
David Boyd
The symbiotic star AG Dra experienced a double-peaked outburst of 0.6 magnitudes in April and May 2016. Photometry and spectroscopy through the outburst showed the B-V colour index…
Changes in the spectrum of Z Ursae Majoris during its rise through a maximum in June 2014
David Boyd
The semiregular variable Z UMa experienced a particularly deep minimum at the end of March 2014 followed by a three month rise to maximum. The rise and subsequent decline were foll…
CCD photometry of the first observed superoutburst of KP Cassiopeiae in 2008 October
David Boyd, Pierre dePonthiere, Jerry Foote +7
We report CCD photometry and analysis of the first observed superoutburst of the SU UMa-type dwarf nova KP Cassiopeiae during 2008 October. We observed a distinct shortening of the…
Results of a campaign to observe outbursts of the dwarf nova CSS 121005:212625+201948
Jeremy Shears, James Boardman, David Boyd +9
A monitoring programme of CSS 121005:212625+201948 covering nearly two observing seasons has shown that it is a typical SU UMa dwarf nova, but it has one of the shortest supercycle…
Superhumps and post-outburst rebrightening episodes in the AM CVn star SDSS J012940.05+384210.4
Jeremy Shears, Steve Brady, Robert Koff +2
We report unfiltered photometry of the first confirmed outburst of the AM CVn system SDSS J012940.05+384210.4 during 2009 December. At its brightest the star was magnitude 14.5, 5.…
Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. II: The Second Year (2009-2010)
Taichi Kato, Hiroyuki Maehara, Makoto Uemura +56
As an extension of the project in Kato et al. (2009, arXiv:0905.1757), we collected times of superhump maxima for 61 SU UMa-type dwarf novae mainly observed during the 2009-2010 se…
TU Tau B: The Peculiar 'Eclipse' of a possible proto-Barium Giant
Richard O. Gray, Christopher J. Corbally, Michael M. Briley +26
TU Tau (= HD 38218 = HIP 27135) is a binary system consisting of a C-N carbon star primary and an A-type secondary. We report on new photometry and spectroscopy which tracked the r…
Determination of the superhump period of the dwarf nova V701 Tau during the 2005 December superoutburst
Jeremy Shears, David Boyd
We report new measurements of the superhump period of the UGSU-type dwarf nova V701 Tau during the 2005 December superoutburst. Using unfiltered time series CCD observations on 3 n…
The orbital period of the eclipsing dwarf nova CG Draconis
Jeremy Shears, David Boyd, Steve Brady +1
We have performed time resolved photometry on the dwarf nova CG Dra and have established for the first time that it is an eclipsing system. By measuring the times of the eclipses,…
Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. V: The Fifth Year (2012-2013)
Taichi Kato, Franz-Josef Hambsch, Hiroyuki Maehara +84
Continuing the project described by Kato et al. (2009a, arXiv:0905.1757), we collected times of superhump maxima for SU UMa-type dwarf novae mainly observed during the 2012-2013 se…
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…
CCD photometry and visual observations of V1663 Aquilae (Nova Aquilae 2005)
David Boyd, Gary Poyner
We present CCD V and I band photometry and visual observations of V1663 Aquilae (Nova Aquilae 2005). This was a classical fast nova, probably of type Ba, observed for the first tim…
A Study of the Orbital Periods of Deeply Eclipsing SW Sextantis Stars
David Boyd
Results are presented of a five-year project to study the orbital periods of eighteen deeply eclipsing novalike cataclysmic variables, collectively known as SW Sextantis stars, by…
Faint-state transitions in the SW Sextantis nova-like variable, HS 0455+8315
Jeremy Shears, Boris Gaensicke, Pablo Rodriguez-Gil +3
We present the fourteen year-long light curve of the SW Sextantis nova-like variable, HS 0455+8315, from 2000 November to 2015 February which reveals two deep faint states at magni…
GSC2.3 N152008120 - a new SU UMa-type dwarf nova in Draco
David Boyd, Keith Graham, Taichi Kato +5
We report observations during 2008 October of the first recorded superoutburst of a previously unknown SU UMa-type dwarf nova in Draco located at 19h 14m 43.52s +60d 52m 14.1s (J20…
Determining the magnitudes and spectral types of the components of the binary Mira X Ophiuchi
David Boyd
Several values for the magnitudes and spectral types of the components of the binary Mira X Ophiuchi have been published in the literature over the last century. Analysis of new ph…
Superhumps and flickering in V1316 Cygni
David Boyd, Christopher Lloyd, Robert Koff +7
We present analysis and results of a coordinated CCD photometry campaign to observe the 2006 June superoutburst of the cataclysmic variable V1316 Cyg involving 8 longitudinally-dis…
Evidence of abrupt changes in the orbital periods of two cataclysmic variables
David Boyd
We report evidence from eclipse timing that two otherwise apparently normal cataclysmic variables have experienced abrupt changes in their orbital periods. The orbital period of HS…
HW Bootis: an enigmatic cataclysmic variable star
Jeremy Shears, David Boyd, Graham Darlington +6
We present the 13-year light curve of HW Boo between 2001 May and 2014 May. We identified 12 outbursts, which typically lasted 2 to 5 days, with an amplitude of 2.7 to 3.6 magnitud…
Superhumps and grazing eclipses in the dwarf nova BG Arietis
Jeremy Shears, David Boyd, Tut Campbell +7
We report unfiltered photometry of BG Arietis (= SDSS J015151.87+140047.2) in 2009 and 2010 which shows the presence of superhumps with peak-to-peak amplitude of up to 0.36 magnitu…
Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae
Taichi Kato, Akira Imada, Makoto Uemura +60
We systematically surveyed period variations of superhumps in SU UMa-type dwarf novae based on newly obtained data and past publications. In many systems, the evolution of superhum…
Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. IV: The Fourth Year (2011-2012)
Taichi Kato, Franz-Josef Hambsch, Hiroyuki Maehara +85
Continuing the project described by Kato et al. (2009, arXiv:0905.1757), we studied 86 SU UMa-type dwarf novae. We confirmed the general trends such as the relation between period…
Photometry and Spectroscopy of the Symbiotic Binary V1413 Aquilae during the 2024 Eclipse
David Boyd, David Cejudo, James Foster +2
We report our photometric and spectroscopic observations and analysis of the 2024 eclipse of the symbiotic binary V1413 Aquilae. We found the system in a visually bright state and…
The Unusual Eruption of the Extragalactic Classical Nova M31N 2017-09a
Christopher Lloyd, Lewis M. Cook, Seiichiro Kiyota +10
M31N 2017-09a is a classical nova and was observed for some 160 days following its initial eruption, during which time it underwent a number of bright secondary outbursts. The ligh…