194 citations · 1.1k across the 54 of their papers we have counts for
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A survey for variable young stars with small telescopes - XI. Spot Lifetimes and Coverage Distributions
Dirk Froebrich, Carys Herbert, Aleks Scholz +47
We present a homogeneous analysis of rotational variability and spot properties in young stellar objects across multiple star-forming regions observed by the Hunting Outbursting Yo…
A probable inside-out dwarf nova outburst from the period bouncer candidate ASASSN-25dc
Yusuke Tampo, Naoto Kojiguchi, Mariko Kimura +13
We report optical time-resolved photometric observations of a newly-discovered outbursting system, ASASSN-25dc. Its 8-mag amplitude, 40-day duration, 1-mag dip in the outburst plat…
Gaia24ccy: An outburst followed the footsteps of its predecessor
Koshvendra Singh, Joe P. Ninan, Zhen Guo +25
Accretion-driven outbursts in young stellar objects remain poorly understood, largely limited by a statistically small sample of closely followed-up events. This underscores the im…
Gaia20fnr: A binary-lens microlensing event with full orbital motion revealed by four space telescopes
M. Wicker, Ł. Wyrzykowski, M. Hundertmark +49
The microlensing event Gaia20fnr is a long-duration, non-caustic-crossing binary-lens event at high Galactic latitude. Triggered by a photometric rise detected by the Gaia space mi…
The evolutionary history of ultra-compact accreting binaries. I. Chemical abundances and formation channel of the eclipsing AM CVn system ZTF J225237.05-051917.4 from HST spectroscopy
W. Yu, A. F. Pala, T. Kupfer +33
AM Canum Venaticorum (AM CVn) stars are ultra-compact binary systems composed of a white dwarf (WD) primary accreting from a H-deficient donor. They are important as potential prog…
TESS and ground-based observations of WZ Sge-type dwarf novae in outburst
Y. Tampo, N. Kojiguchi, K. Isogai +30
Dwarf nova (DN) superoutbursts are accompanied by superhumps, which change their periods and profiles over a superoutburst. We present the TESS and ground-based observations of nin…
Revisiting the extremely long-period cataclysmic variables V479 Andromedae and V1082 Sagitarii
Gagik Tovmassian, Diogo Belloni, Anna F. Pala +56
The overwhelming majority of CVs have orbital periods shorter than 10 hr. However, a few have much longer periods, and their formation and existence pose challenges for the CV evol…
TCP J072226836220548: a new AM CVn type system with infrequent outbursts
Alexander Tarasenkov, Kirill Sokolovsky, Alexandr Dodin +11
We present the discovery of TCP J072226836220548, a new ultracompact binary system of the AM CVn type. This system was first identified displaying a mag outburst on 2…
A targeted search for binary white dwarf pulsars using Gaia and WISE
Ingrid Pelisoli, T. R. Marsh, G. Tovmassian +24
After its discovery in 2016, the white dwarf binary AR Scorpii (AR Sco) remained for several years the only white dwarf system to show pulsed radio emission associated with a fast-…
Is the Symbiotic Recurrent Nova T CrB Late? Recent Photometric Evolution and Comparison with Past Pre-Outburst Behaviour
Jaroslav Merc, Łukasz Wyrzykowski, Paul G. Beck +46
T CrB is a symbiotic recurrent nova that last erupted in 1946. Given its recurrence timescale of approximately 80 years, the next outburst is eagerly anticipated by the astronomica…
ASASSN-24hd; a dwarf nova bridging WZ Sge-type and SU UMa-type superoutbursts
Yusuke Tampo, Naoto Kojiguchi, Taichi Kato +9
WZ Sge-type dwarf novae (DNe) form a subclass in cataclysmic variables, characterized by short-period variations called superhumps during an outburst. Here we present optical groun…
GOTO065054+593624: a 8.5 mag amplitude dwarf nova identified in real time via Kilonova Seekers
T. L. Killestein, G. Ramsay, M. Kennedy +62
Dwarf novae are astrophysical laboratories for probing the nature of accretion, binary mass transfer, and binary evolution -- yet their diverse observational characteristics contin…
A long-duration superflare on the K giant HD 251108
Hans Moritz Günther, Dheeraj Pasham, Alexander Binks +10
Many giant stars are magnetically active, which causes rotational variability, chromospheric emission lines, and X-ray emission. Large outbursts in these emission features can set…
MASTER OT J030227.28+191754.5: an unprecedentedly energetic dwarf nova outburst
Yusuke Tampo, Taichi Kato, Keisuke Isogai +60
We present a detailed study of the MASTER OT J030227.28+191754.5 outburst in 2021-2022, reaching an amplitude of 10.2 mag and a duration of 60 d. The detections of (1) the double-p…
Accretion Funnel Reconfiguration during an Outburst in a Young Stellar Object: EX Lupi
Koshvendra Singh, Joe P. Ninan, Marina M. Romanova +14
EX Lupi, a low-mass young stellar object, went into an accretion-driven outburst in March of 2022. The outburst caused a sudden phase change of ~ 112 5 in…
Optical and soft X-ray light-curve analysis during the 2022 eruption of U Scorpii: structural changes in the accretion disk
Katsuki Muraoka, Naoto Kojiguchi, Junpei Ito +52
We present our optical photometric observations of the 2022 eruption of the recurrent nova U Scorpii (U Sco) using 49,152 data points over 70 d following the optical peak. We have…
A survey for variable young stars with small telescopes: VIII -- Properties of 1687 Gaia selected members in 21 nearby clusters
Dirk Froebrich, Aleks Scholz, Justyn Campbell-White +60
The Hunting Outbursting Young Stars (HOYS) project performs long-term, optical, multi-filter, high cadence monitoring of 25 nearby young clusters and star forming regions. Utilisin…
The Accretion History of EX Lup: A Century of Bursts, Outbursts, and Quiescence
Mu-Tian Wang, Gregory J. Herczeg, Hui-Gen Liu +11
EX Lup is the archetype for the class of young stars that undergoes repeated accretion outbursts of mag at optical wavelengths and that last for months. Despite extensive…
ASASSN-22ak: La Belle au bois dormant in a hydrogen-depleted dwarf nova?
Taichi Kato, Franz-Josef Hambsch, Berto Monard +1
ASASSN-22ak is a transient discovered by the All-Sky Automated Survey for Supernovae and by Gaia in 2022 January. Although this object had been in deep quiescence at least for seve…
Modeling the Multiwavelength Evolution of the V960 Mon System
Adolfo S. Carvalho, Lynne A. Hillenbrand, Franz-Josef Hambsch +7
We study the evolution of the FU Ori object V960 Mon since its outburst, using available multi-wavelength photometric time series over 8 years, complemented by several epochs of mo…
2021 superoutburst of WZ Sge-type dwarf nova V627 Pegasi lacks an early superhump phase
Yusuke Tampo, Taichi Kato, Naoto Kojiguchi +27
Superoutbursts in WZ Sge-type dwarf novae (DNe) are characterized by both early superhumps and ordinary superhumps originating from the 2:1 and 3:1 resonances, respectively. Howeve…
On the orbital period of the dwarf nova CW Mon
Taichi Kato, Franz-Josef Hambsch
CW Mon is a relatively bright and nearby SS Cyg-type dwarf nova frequently used in detailed analysis of cataclysmic variables and statistical studies. Using Transiting Exoplanet Su…
A survey for variable young stars with small telescopes: VI -- Analysis of the outbursting Be stars NSW284, Gaia19eyy, and VES263
Dirk Froebrich, Lynne A. Hillenbrand, Carys Herbert +44
This paper is one in a series reporting results from small telescope observations of variable young stars. Here, we study the repeating outbursts of three likely Be stars based on…
PNV J00444033+4113068: early superhumps with 0.7 mag amplitude and non-red color
Yusuke Tampo, Keisuke Isogai, Naoto Kojiguchi +13
In the first days of WZ Sge-type dwarf nova (DN) outbursts, the 2:1 resonance induces a spiral arm structure in the accretion disk, which is observed as early superhumps in optical…