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Dr Simone Scaringi's Outputs (91)

Discovery of persistent quasi-periodic oscillations in accreting white dwarfs: a new link to X-ray binaries (2024)
Journal Article
Veresvarska, M., Scaringi, S., Knigge, C., Paice, J., Buckley, D. A. H., Segura, N. C., de Martino, D., Groot, P. J., Ingram, A., Irving, Z. A., & Szkody, P. (2024). Discovery of persistent quasi-periodic oscillations in accreting white dwarfs: a new link to X-ray binaries. Monthly Notices of the Royal Astronomical Society, 534(4), 3087-3103. https://doi.org/10.1093/mnras/stae2279

Almost all accreting black hole and neutron star (NS) X-ray binary systems (XRBs) exhibit prominent brightness variations on a few characteristic time-scales and their harmonics. These quasi-periodic oscillations (QPOs) are thought to be associated w... Read More about Discovery of persistent quasi-periodic oscillations in accreting white dwarfs: a new link to X-ray binaries.

Unveiling the nature of two dwarf novae: CRTS J080846.2+313106 and V416 Dra (2024)
Journal Article
Joshi, A., Catelan, M., Scaringi, S., Schwope, A., Anupama, G. C., Rawat, N., Sahu, D. K., Singh, M., Dastidar, R., Subramanian, R. V., & Rao, S. M. (2024). Unveiling the nature of two dwarf novae: CRTS J080846.2+313106 and V416 Dra. Astronomy & Astrophysics, 689, Article A158. https://doi.org/10.1051/0004-6361/202348307

We present the analysis of optical photometric and spectroscopic observations of two non-magnetic cataclysmic variables, namely CRTS J080846.2+313106 and V416 Dra. We find CRTS J080846.2+313106 to vary with a period of 4.9116 ± 0.0003 h, which was no... Read More about Unveiling the nature of two dwarf novae: CRTS J080846.2+313106 and V416 Dra.

Ancient Nova Shells of RX Pup Indicate Evolution of Mass Transfer Rate (2024)
Journal Article
Iłkiewicz, K., Mikołajewska, J., Shara, M. M., Faherty, J. K., & Scaringi, S. (2024). Ancient Nova Shells of RX Pup Indicate Evolution of Mass Transfer Rate. Astrophysical Journal Letters, 972(1), Article L14. https://doi.org/10.3847/2041-8213/ad6e5a

RX Pup is a symbiotic binary that experienced a nova outburst in the 1970s. Here we report a discovery of a ∼1300 yr old nova shell around the system and a possible detection of a ∼7000 yr old nova shell. Together with the nova shell ejected in the 1... Read More about Ancient Nova Shells of RX Pup Indicate Evolution of Mass Transfer Rate.

Following the Pulsations in the Long-term Cooling of GW Librae and V386 Serpentis (2024)
Journal Article
Szkody, P., van Roestel, J., Bell, K. J., Vanderbosch, Z. P., Mukadam, A., & Scaringi, S. (2024). Following the Pulsations in the Long-term Cooling of GW Librae and V386 Serpentis. Astronomical Journal, 168(3), Article 114. https://doi.org/10.3847/1538-3881/ad656f

GW Lib and V386 Ser are dwarf novae systems containing pulsating white dwarfs that underwent large 8–9 mag amplitude outbursts in 2007 and 2019, respectively. Following the pulsation periods in these systems after the outburst provides a means to vie... Read More about Following the Pulsations in the Long-term Cooling of GW Librae and V386 Serpentis.

Optical spectroscopic and photometric classification of the X-ray transient EP240309a (EP J115415.8−501810) as an intermediate polar (2024)
Journal Article
Potter, S. B., Buckley, D. A. H., Scaringi, S., Monageng, I. M., Egbo, O. D., Charles, P. A., …Hlakola, M. (2024). Optical spectroscopic and photometric classification of the X-ray transient EP240309a (EP J115415.8−501810) as an intermediate polar. Monthly Notices of the Royal Astronomical Society: Letters, 532(1), L21-L26. https://doi.org/10.1093/mnrasl/slae038

We report on optical follow-up observations of an X-ray source initially detected by the Einstein Probe mission. Our investigations categorize the source as an intermediate polar, a class of magnetic cataclysmic variables, exhibiting an orbital perio... Read More about Optical spectroscopic and photometric classification of the X-ray transient EP240309a (EP J115415.8−501810) as an intermediate polar.

Burst-induced spin variations in the accreting magnetic white dwarf PBC J0801.2–4625 (2024)
Journal Article
Irving, Z. A., Altamirano, D., Scaringi, S., Veresvarska, M., Knigge, C., Castro Segura, N., …Iłkiewicz, K. (2024). Burst-induced spin variations in the accreting magnetic white dwarf PBC J0801.2–4625. Monthly Notices of the Royal Astronomical Society, 530(4), 3974-3985. https://doi.org/10.1093/mnras/stae1103

PBC J0801.2–4625 is an intermediate polar with a primary spin frequency of 66.08 d−1 and an unknown orbital period. The long-term All Sky Automated Survey for Supernovae (ASAS-SN) light curve of this system reveals four bursts, all of which have simi... Read More about Burst-induced spin variations in the accreting magnetic white dwarf PBC J0801.2–4625.

TESS Photometry of AM Her and AR UMa: Binary Parameters, Cyclotron Emission Modeling, and Mass Transfer Duty Cycles (2024)
Journal Article
Mason, P. A., Hakala, P., Wu, K., Barrett, P. E., Iłkiewicz, K., Littlefield, C., …Scaringi, S. (2024). TESS Photometry of AM Her and AR UMa: Binary Parameters, Cyclotron Emission Modeling, and Mass Transfer Duty Cycles. Astrophysical Journal, 965(1), Article 96. https://doi.org/10.3847/1538-4357/ad27d7

Transiting Exoplanet Survey Satellite (TESS) photometry of the polars AM Herculis (AM Her) and AR Ursae Majoris (AR UMa) is presented, along with high-speed photometry. AM Her shows a variety of high states with frequent transitions between them. TES... Read More about TESS Photometry of AM Her and AR UMa: Binary Parameters, Cyclotron Emission Modeling, and Mass Transfer Duty Cycles.

Evolution of spin in the intermediate polar CC sculptoris (2024)
Journal Article
Paice, J. A., Scaringi, S., Castro Segura, N., Sahu, A., Iłkiewicz, K., Coppejans, D. L., …Veresvarska, M. (2024). Evolution of spin in the intermediate polar CC sculptoris. Monthly Notices of the Royal Astronomical Society: Letters, 531(1), L82-L86. https://doi.org/10.1093/mnrasl/slae035

We report on spin variations in the intermediate polar and cataclysmic variable CC Scl, as seen by the Transiting Exoplanet Survey Satellite (TESS). By studying both the spin period and its harmonic, we find that the spin has varied since it was firs... Read More about Evolution of spin in the intermediate polar CC sculptoris.

The Peculiar Bursting Nature of CP Pup (2024)
Journal Article
Veresvarska, M., Scaringi, S., Hagen, S., De Martino, D., Done, C., Ilkiewicz, K., …Littlefield, C. (2024). The Peculiar Bursting Nature of CP Pup. Monthly Notices of the Royal Astronomical Society, 529(1), 664-672. https://doi.org/10.1093/mnras/stae573

The classical nova CP Puppis has been observed to have particularly puzzling and peculiar properties. In particular, this classical nova displays occasional bursts in its long-term ASAS-SN light curve. Here, we report on five sectors of TESS data dis... Read More about The Peculiar Bursting Nature of CP Pup.

Classifying Optical (Out)bursts in Cataclysmic Variables: The Distinct Observational Characteristics of Dwarf Novae, Micronovae, Stellar Flares, and Magnetic Gating (2024)
Journal Article
Iłkiewicz, K., Scaringi, S., Veresvarska, M., De Martino, D., Littlefield, C., Knigge, C., …Sahu, A. (2024). Classifying Optical (Out)bursts in Cataclysmic Variables: The Distinct Observational Characteristics of Dwarf Novae, Micronovae, Stellar Flares, and Magnetic Gating. Astrophysical Journal Letters, 962(2), Article L34. https://doi.org/10.3847/2041-8213/ad243c

Cataclysmic variables can experience short optical brightenings, which are commonly attributed to phenomena such as dwarf novae outbursts, micronovae, donor flares, or magnetic gating bursts. Since these events exhibit similar observational character... Read More about Classifying Optical (Out)bursts in Cataclysmic Variables: The Distinct Observational Characteristics of Dwarf Novae, Micronovae, Stellar Flares, and Magnetic Gating.

MELCHIORS: The Mercator Library of High Resolution Stellar Spectroscopy (2024)
Journal Article
Royer, P., Merle, T., Dsilva, K., Sekaran, S., Van Winckel, H., Frémat, Y., …Waelkens, C. (2024). MELCHIORS: The Mercator Library of High Resolution Stellar Spectroscopy. Astronomy & Astrophysics, 681, Article A107. https://doi.org/10.1051/0004-6361/202346847

Aims. Over the past decades, libraries of stellar spectra have been used in a large variety of science cases, including as sources of reference spectra for a given object or a given spectral type. Despite the existence of large libraries and the incr... Read More about MELCHIORS: The Mercator Library of High Resolution Stellar Spectroscopy.

Digging a little deeper: characterizing three new extreme ULX candidates (2023)
Journal Article
Roberts, T. P., Walton, D. J., Mackenzie, A. D. A., Heida, M., & Scaringi, S. (2023). Digging a little deeper: characterizing three new extreme ULX candidates. Monthly Notices of the Royal Astronomical Society, 525(3), 3330-3343. https://doi.org/10.1093/mnras/stad2367

A prime motivation for compiling catalogues of any celestial X-ray source is to increase our numbers of rare subclasses. In this work, we take a recent multimission catalogue of ultraluminous X-ray sources (ULXs) and look for hitherto poorly-studied... Read More about Digging a little deeper: characterizing three new extreme ULX candidates.

Cataclysmic variables are a key population of gravitational wave sources for LISA (2023)
Journal Article
Scaringi, S., Breivik, K., Littenberg, T. B., Knigge, C., Groot, P. J., & Veresvarska, M. (2023). Cataclysmic variables are a key population of gravitational wave sources for LISA. Monthly Notices of the Royal Astronomical Society: Letters, 525(1), L50-L55. https://doi.org/10.1093/mnrasl/slad093

The gravitational wave (GW) signals from the Galactic population of cataclysmic variables (CVs) have yet to be carefully assessed. Here, we estimate these signals and evaluate their significance for Laser Interferometer Space Antenna (LISA). First, w... Read More about Cataclysmic variables are a key population of gravitational wave sources for LISA.

SDSS J134441.83+204408.3: A Highly Asynchronous Short-period Magnetic Cataclysmic Variable with a 56 MG Field Strength (2023)
Journal Article
Littlefield, C., Mason, P. A., Garnavich, P., Szkody, P., Thorstensen, J., Scaringi, S., …Wells, N. (2023). SDSS J134441.83+204408.3: A Highly Asynchronous Short-period Magnetic Cataclysmic Variable with a 56 MG Field Strength. Astrophysical Journal Letters, 943(2), Article L24. https://doi.org/10.3847/2041-8213/acaf04

When the accreting white dwarf in a magnetic cataclysmic variable star (mCV) has a field strength in excess of 10 MG, it is expected to synchronize its rotational frequency to the binary orbit frequency, particularly at small binary separations, due... Read More about SDSS J134441.83+204408.3: A Highly Asynchronous Short-period Magnetic Cataclysmic Variable with a 56 MG Field Strength.

Kepler K2 and TESS Observations of Two Magnetic Cataclysmic Variables: The New Asynchronous Polar SDSS J084617.11+245344.1 and Paloma (2023)
Journal Article
Littlefield, C., Hoard, D., Garnavich, P., Szkody, P., Mason, P. A., Scaringi, S., …Jayaraman, R. (2023). Kepler K2 and TESS Observations of Two Magnetic Cataclysmic Variables: The New Asynchronous Polar SDSS J084617.11+245344.1 and Paloma. Astronomical Journal, 165(2), Article 43. https://doi.org/10.3847/1538-3881/aca1a5

There have been relatively few published long-duration, uninterrupted light curves of magnetic cataclysmic variable stars in which the accreting white dwarf's rotational frequency is slightly desynchronized from the binary orbital frequency. We repor... Read More about Kepler K2 and TESS Observations of Two Magnetic Cataclysmic Variables: The New Asynchronous Polar SDSS J084617.11+245344.1 and Paloma.

SWIFT J0503.7-2819: A nearly synchronous intermediate polar below the period gap? (2022)
Journal Article
Rawat, N., Pandey, J., Joshi, A., Scaringi, S., & Yadava, U. (2022). SWIFT J0503.7-2819: A nearly synchronous intermediate polar below the period gap?. Monthly Notices of the Royal Astronomical Society, 517(2), 1667-1677. https://doi.org/10.1093/mnras/stac2723

Based on the X-ray observations from XMM-Newton and Swift, and optical observations from Transiting Exoplanet Survey Satellite (TESS) and AAVSO, we present temporal and spectral properties of probable intermediate polar SWIFT J0503.7-2819. The X-ray... Read More about SWIFT J0503.7-2819: A nearly synchronous intermediate polar below the period gap?.

Spectroscopic follow-up of a subset of the Gaia/IPHAS catalogue of Hα-excess sources (2022)
Journal Article
Fratta, M., Scaringi, S., Monguió, M., Pala, A., Drew, J., Knigge, C., …Gandhi, P. (2022). Spectroscopic follow-up of a subset of the Gaia/IPHAS catalogue of Hα-excess sources. Monthly Notices of the Royal Astronomical Society, 518(3), 3301-3311. https://doi.org/10.1093/mnras/stac3216

State-of-the-art techniques to identify Hα emission-line sources in narrow-band photometric surveys consist of searching for  Hα excess with reference to nearby objects in the sky (position-based selection). However, while this approach usually yield... Read More about Spectroscopic follow-up of a subset of the Gaia/IPHAS catalogue of Hα-excess sources.

XGAPS: a sub-arcsec cross-match of galactic plane surveys (2022)
Journal Article
Scaringi, S., Monguió, M., Knigge, C., Fratta, M., Gänsicke, B., Groot, P., …Toloza, O. (2022). XGAPS: a sub-arcsec cross-match of galactic plane surveys. Monthly Notices of the Royal Astronomical Society, 518(2), 3137-3146. https://doi.org/10.1093/mnras/stac3353

We present a sub-arcsec cross-match of Gaia Data Release 3 (DR3) against the INT Galactic Plane Surveys (IGAPS) and the United Kingdom Infrared Deep Sky Survey (UKIDSS). The resulting cross-match of Galactic Plane Surveys (XGAPS) provides additional... Read More about XGAPS: a sub-arcsec cross-match of galactic plane surveys.

Outer disc edge: properties of low-frequency aperiodic variability in ultracompact interacting binaries (2022)
Journal Article
Veresvarska, M., & Scaringi, S. (2022). Outer disc edge: properties of low-frequency aperiodic variability in ultracompact interacting binaries. Monthly Notices of the Royal Astronomical Society, 518(4), 5576-5589. https://doi.org/10.1093/mnras/stac3470

Flickering, and more specifically aperiodic broad-band variability, is an important phenomenon used in understanding the geometry and dynamics of accretion flows. Although the inner regions of accretion flows are known to generate variability on rela... Read More about Outer disc edge: properties of low-frequency aperiodic variability in ultracompact interacting binaries.

A Magnetic Valve at L1 Revealed in TESS Photometry of the Asynchronous Polar BY Cam (2022)
Journal Article
Mason, P. A., Littlefield, C., Monroy, L. C., Morales, J. F., Hakala, P., Garnavich, P., …Scaringi, S. (2022). A Magnetic Valve at L1 Revealed in TESS Photometry of the Asynchronous Polar BY Cam. Astrophysical Journal, 938(2), https://doi.org/10.3847/1538-4357/ac91cf

We present TESS photometry of the asynchronous polar BY Cam, which undergoes a beat cycle between the 199.384 min white dwarf (WD) spin period and the 201.244 min orbital period. This results in changes in the flow of matter onto the WD. The TESS lig... Read More about A Magnetic Valve at L1 Revealed in TESS Photometry of the Asynchronous Polar BY Cam.

Locating the flickering source in polars (2022)
Journal Article
Iłkiewicz, K., Scaringi, S., Littlefield, C., & Mason, P. A. (2022). Locating the flickering source in polars. Monthly Notices of the Royal Astronomical Society, 516(4), https://doi.org/10.1093/mnras/stac2597

Flickering is a fast variability observed in all accreting systems. It has been shown that in most cataclysmic variables flickering originates in the accretion disc. However, in polars the strong magnetic field of the white dwarf prevents the formati... Read More about Locating the flickering source in polars.

Characterization of the eclipsing post-common-envelope binary TIC 60040774 (2022)
Journal Article
Priyatikanto, R., Knigge, C., Scaringi, S., Brink, J., & Buckley, D. (2022). Characterization of the eclipsing post-common-envelope binary TIC 60040774. Monthly Notices of the Royal Astronomical Society, 516(1), 1183-1192. https://doi.org/10.1093/mnras/stac2197

Binaries with a white dwarf primary and a main sequence secondary can be used to test our understanding of both single and binary star evolution. A small fraction of such systems experienced a common-envelope phase from which they emerged with a rela... Read More about Characterization of the eclipsing post-common-envelope binary TIC 60040774.

Hitting a New Low: The Unique 28 hr Cessation of Accretion in the TESS Light Curve of YY Dra (DO Dra) (2022)
Journal Article
Hill, K. L., Littlefield, C., Garnavich, P., Scaringi, S., Szkody, P., Mason, P. A., …Covington, A. E. (2022). Hitting a New Low: The Unique 28 hr Cessation of Accretion in the TESS Light Curve of YY Dra (DO Dra). Astronomical Journal, 163(6), Article 246. https://doi.org/10.3847/1538-3881/ac5a51

We present the Transiting Exoplanet Surveying Satellite light curve of the intermediate polar YY Draconis (YY Dra, also known as DO Dra). The power spectrum indicates that while there is stream-fed accretion for most of the observational period, ther... Read More about Hitting a New Low: The Unique 28 hr Cessation of Accretion in the TESS Light Curve of YY Dra (DO Dra).

Localized thermonuclear bursts from accreting magnetic white dwarfs (2022)
Journal Article
Scaringi, S., Groot, P., Knigge, C., Bird, A., Breedt, E., Buckley, D., …Timmes, F. (2022). Localized thermonuclear bursts from accreting magnetic white dwarfs. Nature, 604(7906), 447-450. https://doi.org/10.1038/s41586-022-04495-6

Nova explosions are caused by global thermonuclear runaways triggered in the surface layers of accreting white dwarfs1,2,3. It has been predicted4,5,6 that localized thermonuclear bursts on white dwarfs can also take place, similar to type-I X-ray bu... Read More about Localized thermonuclear bursts from accreting magnetic white dwarfs.

Triggering micronovae through magnetically confined accretion flows in accreting white dwarfs (2022)
Journal Article
Scaringi, S., Groot, P., Knigge, C., Lasota, J., de Martino, D., Cavecchi, Y., …Camisassa, M. (2022). Triggering micronovae through magnetically confined accretion flows in accreting white dwarfs. Monthly Notices of the Royal Astronomical Society: Letters, 514(1), L11-L15. https://doi.org/10.1093/mnrasl/slac042

Rapid bursts at optical wavelengths have been reported for several accreting white dwarfs, where the optical luminosity can increase by up to a factor 30 in less than an hour fading on timescales of several hours, and where the energy release can rea... Read More about Triggering micronovae through magnetically confined accretion flows in accreting white dwarfs.

Discovery and analysis of three magnetic hot subdwarf stars: evidence for merger-induced magnetic fields (2022)
Journal Article
Pelisoli, I., Dorsch, M., Heber, U., Gänsicke, B., Geier, S., Kupfer, T., …Schaffenroth, V. (2022). Discovery and analysis of three magnetic hot subdwarf stars: evidence for merger-induced magnetic fields. Monthly Notices of the Royal Astronomical Society, 515(2), 2496-2510. https://doi.org/10.1093/mnras/stac1069

Magnetic fields can play an important role in stellar evolution. Among white dwarfs, the most common stellar remnant, the fraction of magnetic systems is more than 20 per cent. The origin of magnetic fields in white dwarfs, which show strengths rangi... Read More about Discovery and analysis of three magnetic hot subdwarf stars: evidence for merger-induced magnetic fields.

A persistent ultraviolet outflow from an accreting neutron star binary transient (2022)
Journal Article
Castro Segura, N., Knigge, C., Long, K., Altamirano, D., Armas Padilla, M., Bailyn, C., …Wiseman, P. (2022). A persistent ultraviolet outflow from an accreting neutron star binary transient. Nature, 603(7899), 52-57. https://doi.org/10.1038/s41586-021-04324-2

All disc-accreting astrophysical objects produce powerful disc winds. In compact binaries containing neutron stars or black holes, accretion often takes place during violent outbursts. The main disc wind signatures during these eruptions are blue-shi... Read More about A persistent ultraviolet outflow from an accreting neutron star binary transient.

Rapid Bursts of Magnetically Gated Accretion in the Intermediate Polar V1025 Cen (2022)
Journal Article
Littlefield, C., Lasota, J., Hameury, J., Scaringi, S., Garnavich, P., Szkody, P., …Leichty, M. (2022). Rapid Bursts of Magnetically Gated Accretion in the Intermediate Polar V1025 Cen. Astrophysical Journal Letters, 924(1), https://doi.org/10.3847/2041-8213/ac4262

Magnetically gated accretion has emerged as a proposed mechanism for producing extremely short, repetitive bursts of accretion onto magnetized white dwarfs in intermediate polars (IPs), but this phenomenon has not been detected previously in a confir... Read More about Rapid Bursts of Magnetically Gated Accretion in the Intermediate Polar V1025 Cen.

Astrometric excess noise in Gaia EDR3 and the search for X-ray binaries (2021)
Journal Article
Gandhi, P., Buckley, D., Charles, P., Hodgkin, S., Scaringi, S., Knigge, C., …Zhao, Y. (2022). Astrometric excess noise in Gaia EDR3 and the search for X-ray binaries. Monthly Notices of the Royal Astronomical Society, 510(3), 3885-3895. https://doi.org/10.1093/mnras/stab3771

Astrometric noise (ϵ) in excess of parallax and proper motion is a potential signature of orbital wobble (ω) of individual components in binary star systems. The combination of X-ray selection with astrometric noise could then be a powerful tool for... Read More about Astrometric excess noise in Gaia EDR3 and the search for X-ray binaries.

SU Lyn - a transient symbiotic star (2021)
Journal Article
Iłkiewicz, K., Mikołajewska, J., Scaringi, S., Teyssier, F., Stoyanov, K. A., & Fratta, M. (2022). SU Lyn - a transient symbiotic star. Monthly Notices of the Royal Astronomical Society, 510(2), 2707-2717. https://doi.org/10.1093/mnras/stab3637

SU Lyn is a binary system composed of a white dwarf and a red giant star. Although it is known to be bright and variable at X-ray wavelengths, the optical counterpart of the source appeared as a single red giant without prominent emission lines. Beca... Read More about SU Lyn - a transient symbiotic star.

ASAS J071404+7004.3 – a close, bright nova-like cataclysmic variable with gusty winds (2021)
Journal Article
Inight, K., Gänsicke, B., Blondel, D., Boyd, D., Ashley, R., Knigge, C., …Wheatley, P. (2021). ASAS J071404+7004.3 – a close, bright nova-like cataclysmic variable with gusty winds. Monthly Notices of the Royal Astronomical Society, 510(3), 3605-3621. https://doi.org/10.1093/mnras/stab3662

Despite being bright (V 11.8) and nearby (d = 212 pc) ASAS J071404+7004.3 has only recently been identified as a nova-like cataclysmic variable. We present time-resolved optical spectroscopy obtained at the Isaac Newton and the Hiltner and McGrawHill... Read More about ASAS J071404+7004.3 – a close, bright nova-like cataclysmic variable with gusty winds.

Searching for Diamagnetic Blob Accretion in the 74 day K2 Observation of V2400 Ophiuchi (2021)
Journal Article
Langford, A., Littlefield, C., Garnavich, P., Kennedy, M. R., Scaringi, S., & Szkody, P. (2022). Searching for Diamagnetic Blob Accretion in the 74 day K2 Observation of V2400 Ophiuchi. Astronomical Journal, 163(1), https://doi.org/10.3847/1538-3881/ac3010

Since its discovery in 1995, V2400 Ophiuchi (V2400 Oph) has stood apart from most known intermediate polar cataclysmic variables due to its proposed magnetic field strength (9–27 MG) and diskless accretion. To date, the exact accretion mechanism of t... Read More about Searching for Diamagnetic Blob Accretion in the 74 day K2 Observation of V2400 Ophiuchi.

High-resolution Hα imaging of the northern Galactic plane and the IGAPS image database (2021)
Journal Article
Greimel, R., Drew, J., Monguió, M., Ashley, R., Barentsen, G., Eislöffel, J., …Zijlstra, A. (2021). High-resolution Hα imaging of the northern Galactic plane and the IGAPS image database. Astronomy & Astrophysics, 655, Article A49. https://doi.org/10.1051/0004-6361/202140950

The INT Galactic Plane Survey (IGAPS) is the merger of the optical photometric surveys IPHAS and UVEX based on data from the Isaac Newton Telescope (INT) obtained between 2003 and 2018. It captures the entire northern Galactic plane within the Galact... Read More about High-resolution Hα imaging of the northern Galactic plane and the IGAPS image database.

An accreting white dwarf displaying fast transitional mode switching (2021)
Journal Article
Scaringi, S., de Martino, D., Buckley, D., Groot, P., Knigge, C., Fratta, M., …Papitto, A. (2022). An accreting white dwarf displaying fast transitional mode switching. Nature Astronomy, 6, 98-102. https://doi.org/10.1038/s41550-021-01494-x

Accreting white dwarfs are often found in close binary systems with orbital periods ranging from tens of minutes to several hours. In most cases, the accretion process is relatively steady, with significant modulations only occurring on timescales of... Read More about An accreting white dwarf displaying fast transitional mode switching.

TACOS: TESS AM CVn Outbursts Survey (2021)
Journal Article
Pichardo Marcano, M., Rivera Sandoval, L. E., Maccarone, T. J., & Scaringi, S. (2021). TACOS: TESS AM CVn Outbursts Survey. Monthly Notices of the Royal Astronomical Society, 508(3), 3275-3289. https://doi.org/10.1093/mnras/stab2685

Using Transiting Exoplanet Survey Satellite (TESS), we are doing a systematic study of outbursting AM CVn systems to place some limits on the current outbursts models. We present the TESS light curve (LC) for 9 AM CVns showing both superoutbursts (SO... Read More about TACOS: TESS AM CVn Outbursts Survey.

A characteristic optical variability time scale in astrophysical accretion disks (2021)
Journal Article
Burke, C. J., Shen, Y., Blaes, O., Gammie, C. F., Horne, K., Jiang, Y., …Yang, Q. (2021). A characteristic optical variability time scale in astrophysical accretion disks. Science, 373(6556), 789-792. https://doi.org/10.1126/science.abg9933

Accretion disks around supermassive black holes in active galactic nuclei produce continuum radiation at ultraviolet and optical wavelengths. Physical processes in the accretion flow lead to stochastic variability of this emission on a wide range of... Read More about A characteristic optical variability time scale in astrophysical accretion disks.

Quasi-periodic Oscillations in the TESS Light Curve of TX Col, a Diskless Intermediate Polar on the Precipice of Forming an Accretion Disk (2021)
Journal Article
Littlefield, C., Scaringi, S., Garnavich, P., Szkody, P., Kennedy, M. R., Iłkiewicz, K., & Mason, P. A. (2021). Quasi-periodic Oscillations in the TESS Light Curve of TX Col, a Diskless Intermediate Polar on the Precipice of Forming an Accretion Disk. Astronomical Journal, 162(2), Article 49. https://doi.org/10.3847/1538-3881/ac062b

One of the fundamental properties of an intermediate polar is the dynamical nature of the accretion flow as it encounters the white dwarf’s (WD’s) magnetosphere. Many works have presumed a dichotomy between disk-fed accretion, in which the WD accrete... Read More about Quasi-periodic Oscillations in the TESS Light Curve of TX Col, a Diskless Intermediate Polar on the Precipice of Forming an Accretion Disk.

Population-based identification of H α-excess sources in the Gaia DR2 and IPHAS catalogues (2021)
Journal Article
Fratta, M., Scaringi, S., Drew, J., Monguió, M., Knigge, C., Maccarone, T., …Gänsicke, B. (2021). Population-based identification of H α-excess sources in the Gaia DR2 and IPHAS catalogues. Monthly Notices of the Royal Astronomical Society, 505(1), 1135-1152. https://doi.org/10.1093/mnras/stab1258

We present a catalogue of point-like H α-excess sources in the Northern Galactic Plane. Our catalogue is created using a new technique that leverages astrometric and photomeric information from Gaia to select H α-bright outliers in the INT Photometri... Read More about Population-based identification of H α-excess sources in the Gaia DR2 and IPHAS catalogues.

Exploring the tilted accretion disc of AQ Men with TESS (2021)
Journal Article
Iłkiewicz, K., Scaringi, S., Court, J. M., Maccarone, T. J., Altamirano, D., Bradshaw, C. W., …Wijnands, R. (2021). Exploring the tilted accretion disc of AQ Men with TESS. Monthly Notices of the Royal Astronomical Society, 503(3), 4050-4060. https://doi.org/10.1093/mnras/stab664

AQ Men is a nova-like variable that is presumed to have a tilted, precessing accretion disc. Grazing eclipses in this system have been speculated to be useful in exploring the geometry of its accretion disc. In this work, we analysed Transiting Exopl... Read More about Exploring the tilted accretion disc of AQ Men with TESS.

Periodicities in the K2 light curve of HP Librae (2020)
Journal Article
Solanki, S., Kupfer, T., Blaes, O., Breedt, E., & Scaringi, S. (2021). Periodicities in the K2 light curve of HP Librae. Monthly Notices of the Royal Astronomical Society, 500(1), 1222-1230. https://doi.org/10.1093/mnras/staa3240

We analyse Kepler/K2 light-curve data of the AM CVn system HP Librae (HP Lib). We detect with confidence four photometric periodicities in the system: the orbital frequency, both positive and negative superhumps, and the positive apsidal precession f... Read More about Periodicities in the K2 light curve of HP Librae.

Optical Variability of the Dwarf AGN NGC 4395 from the Transiting Exoplanet Survey Satellite (2020)
Journal Article
Burke, C. J., Shen, Y., Chen, Y., Scaringi, S., Faucher-Giguere, C., Liu, X., & Yang, Q. (2020). Optical Variability of the Dwarf AGN NGC 4395 from the Transiting Exoplanet Survey Satellite. Astrophysical Journal, 899(2), https://doi.org/10.3847/1538-4357/aba3ce

We present optical light curves from the Transiting Exoplanet Survey Satellite (TESS) for the archetypical dwarf active galactic nucleus (AGN) in the nearby galaxy NGC 4395 hosting a ~105 M⊙ supermassive black hole (SMBH). Significant variability is... Read More about Optical Variability of the Dwarf AGN NGC 4395 from the Transiting Exoplanet Survey Satellite.

The eclipsing accreting white dwarf Z chameleontis as seen with TESS (2019)
Journal Article
Court, J., Scaringi, S., Rappaport, S., Zhan, Z., Littlefield, C., Castro Segura, N., …Garnavich, P. (2019). The eclipsing accreting white dwarf Z chameleontis as seen with TESS. Monthly Notices of the Royal Astronomical Society, 488(3), 4149-4160. https://doi.org/10.1093/mnras/stz2015

We present results from a study of TESS observations of the eclipsing dwarf nova system Z Cha, covering both an outburst and a superoutburst. We discover that Z Cha undergoes hysteretic loops in eclipse depth – out-of-eclipse flux space in both the o... Read More about The eclipsing accreting white dwarf Z chameleontis as seen with TESS.

The Gaia/IPHAS and Gaia/KIS value-added catalogues (2018)
Journal Article
Scaringi, S., Knigge, C., Drew, J., Monguió, M., Breedt, E., Fratta, M., …Schill, C. (2018). The Gaia/IPHAS and Gaia/KIS value-added catalogues. Monthly Notices of the Royal Astronomical Society, 481(3), 3357-3369. https://doi.org/10.1093/mnras/sty2498

We present a sub-arcsecond crossmatch of Gaia DR2 against the INT Photometric H α Survey of the Northern Galactic Plane Data Release 2 (IPHAS DR2) and the Kepler-INT Survey (KIS). The resulting value-added catalogues (VACs) provide additional precise... Read More about The Gaia/IPHAS and Gaia/KIS value-added catalogues.

Magnetically gated accretion in an accreting ‘non-magnetic’ white dwarf (2017)
Journal Article
Scaringi, S., Maccarone, T., D’Angelo, C., Knigge, C., & Groot, P. (2017). Magnetically gated accretion in an accreting ‘non-magnetic’ white dwarf. Nature, 552(7684), 210-213. https://doi.org/10.1038/nature24653

White dwarfs are often found in binary systems with orbital periods ranging from tens of minutes to hours in which they can accrete gas from their companion stars. In about 15 per cent of these binaries, the magnetic field of the white dwarf is stron... Read More about Magnetically gated accretion in an accreting ‘non-magnetic’ white dwarf.

A determination of the space density and birth rate of hydrogen-line (DA) white dwarfs in the Galactic plane, based on the UVEX survey (2013)
Journal Article
Verbeek, K., Groot, P. J., Nelemans, G., Scaringi, S., Napiwotzki, R., Drew, J. E., …Zijlstra, A. A. (2013). A determination of the space density and birth rate of hydrogen-line (DA) white dwarfs in the Galactic plane, based on the UVEX survey. Monthly Notices of the Royal Astronomical Society, 434(4), https://doi.org/10.1093/mnras/stt1005

The orbital period in the supergiant fast X-ray transient IGR J16465−4507 (2010)
Journal Article
Clark, D., Sguera, V., Bird, A., McBride, V., Hill, A., Scaringi, S., Drave, S., Bazzano, A., & Dean, A. (2010). The orbital period in the supergiant fast X-ray transient IGR J16465−4507. Monthly Notices of the Royal Astronomical Society: Letters, 406(1), L75–L79. https://doi.org/10.1111/j.1745-3933.2010.00885.x

Timing analysis of the INTEGRAL-IBIS and Swift-BAT light curves of the supergiant fast X-ray transient (SFXT) IGR J16465−4507 has identified a period of 30.32 ± 0.02 d which we interpret as the orbital period of the binary system. In addition 11 outb... Read More about The orbital period in the supergiant fast X-ray transient IGR J16465−4507.