Paul Mason

Paul Mason
New Mexico State University | NMSU · DACC - Department of Science

PhD

About

130
Publications
6,040
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679
Citations
Citations since 2017
36 Research Items
338 Citations
2017201820192020202120222023020406080
2017201820192020202120222023020406080
2017201820192020202120222023020406080
2017201820192020202120222023020406080
Introduction
Paul Mason currently works at New Mexico State University. Paul does research in Astrophysics, Astronomy, and Astrobiology.
Additional affiliations
August 2001 - April 2017
University of Texas at El Paso
Position
  • Professor (Assistant)
Description
  • Leader of Astrophysics research team funded by the National Science Foundation. Lecturer and Research Associate.
May 1996 - May 1998
New Mexico State University
Position
  • Researcher
Description
  • Analysis of Compton Gamma-Ray Observatory (CGRO) observations of X-ray binaries and gamma-ray bursts (GRBs),
May 1996 - present
New Mexico State University
Position
  • Professor (Full)
Description
  • Professor. Astrophysics research for undergraduates supported by the Sloan Foundation, SDSS.

Publications

Publications (130)
Preprint
Full-text available
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 to the steep radial dependence of the magnetic field. We report the discovery of an mCV (SDSS J13444...
Article
Full-text available
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 report Kepler K2 and TESS observations of two such systems. The first, SDSS J084617.11+245344.1, was obse...
Article
Full-text available
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 light curve covers 92% of the beat cycle once and 71% of the beat cycle twice. The strongest photometri...
Article
Full-text available
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 formation of an accretion disc. Therefore, the origin of flickering in polars is not clear. We analysed the...
Preprint
Full-text available
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 formation of an accretion disc. Therefore, the origin of flickering in polars is not clear. We analyzed the...
Preprint
Full-text available
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 light curve covers 92% of the beat cycle once and 71% of the beat cycle twice. The strongest photometri...
Article
Full-text available
Polars are highly magnetic cataclysmic variables which have been long observed to have both high and low brightness states. The duration of these states has been previously seen to vary from a number of days up to years. Despite this; these states and their physical origin has not been explained in a consistent manner. We present observations of th...
Preprint
Full-text available
Polars are highly magnetic cataclysmic variables which have been long observed to have both high and low brightness states. The duration of these states has been previously seen to vary from a number of days up to years. Despite this; these states and their physical origin has not been explained in a consistent manner. We present observations of th...
Article
Full-text available
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, there is a day-long, flat-bottomed low state at the beginning of 2020 during which the only periodic sig...
Preprint
Full-text available
We analyze two sectors of TESS photometry of the nova-like cataclysmic variable star V533 Her. We detect a periodicity consistent with the binary orbital period and estimate a revised value of 3.53709(2) hr. We also detect a strong signal near a period of 3.8 h that we associate with positive superhumps. The superhump frequency varies over the TESS...
Preprint
Full-text available
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 (asynchronous polars). We report Kepler K2 and TESS observations of two such systems. The first, SDSS J084617...
Preprint
Full-text available
We present the Transiting Exoplanet Surveying Satellite (TESS) 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, there is a day-long, flat-bottomed low state at the beginning of 2020 during which the only perio...
Article
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 accretes from a Keplerian disk, and stream-fed accretion, in which the matter stream from the donor star di...
Preprint
Full-text available
One of the fundamental properties of an intermediate polar is the dynamical nature of the accretion flow as it encounters the white dwarf's magnetosphere. Many works have presumed a dichotomy between disk-fed accretion, in which the WD accretes from a Keplerian disk, and stream-fed accretion, in which the matter stream from the donor star directly...
Conference Paper
Full-text available
Preprint
Full-text available
The NSF's Karl G. Jansky Very Large Array (VLA) is used to observe 122 magnetic cataclysmic variables (MCVs) during three observing semesters (13B, 15A, and 18A). We report radio detections of 33 stars with fluxes in the range 6--8031 uJy. Twenty-eight stars are new radio sources, increasing the number of radio detected MCVs to more that 40. A surp...
Article
Full-text available
We present a time-series analysis of the asynchronous polar CD Ind, using fast cadence TESS photometry. A similar analysis is performed using ground based photometry of BY Cam. These asynchronous polars show remarkably similar light curves and enigmatic timing characteristics. A pair of competing models for the assignment of the white dwarf spin pe...
Article
The NSF’s Karl G. Jansky Very Large Array (VLA) is used to observe 122 magnetic cataclysmic variables (MCVs) during three observing semesters (13B, 15A, and 18A). We report radio detections of 33 stars with fluxes in the range 6–8031 μJy. Twenty-eight stars are new radio sources, increasing the number of radio detected MCVs to more that 40. A surpr...
Article
We report the discovery of a new eclipsing polar, CRTS J035010.7+323230 (hereafter CRTS J0350+3232). We identified this cataclysmic variable (CV) candidate as a possible polar from its multiyear Catalina Real-Time Transient Survey (CRTS) optical light curve. Photometric monitoring of 22 eclipses in 2015 and 2017 was performed with the 2.1-m Otto St...
Conference Paper
Full-text available
I suggest that many deep connections between astrophysical processes and the emergence and evolution of life in the universe are beginning to be revealed. The universe has changed dramatically over its history and so too have the conditions for life. The multi-frequency nature of cosmic sources has had and continues to have significant effects on t...
Preprint
Full-text available
We present the result of a multi-longitude campaign on the photometric study of the dwarf nova ASASSN-18fk during its superoutburst in 2018. It was observed with 18 telescopes at 15 sites during ~70 nights within a three-month interval. Observations covered the main outburst, six rebrightenings and 50-d decline to a near-quiescent state. We identif...
Preprint
Full-text available
We report the discovery of a new eclipsing polar, CRTS J035010.7+323230 (hereafter CRTS J0350+3232). We identified this cataclysmic variable (CV) candidate as a possible polar from its multi-year Catalina Real-Time Transient Survey (CRTS) optical light curve. Photometric monitoring of 22 eclipses in 2015 and 2017 was performed with the 2.1-m Otto S...
Preprint
Full-text available
The TESS spacecraft observed the asynchronous polar CD Ind at a two-minute cadence almost continuously for 28 days in 2018, covering parts of 5 consecutive cycles of the system's 7.3-day beat period. These observations provide the first uninterrupted photometry of a full spin-orbit beat cycle of an asynchronous polar. Twice per beat cycle, the accr...
Preprint
Full-text available
The bright Nova Cygni 1975 is a rare nova on a magnetic white dwarf (WD). Later it was found to be an asynchronous polar, now called V1500 Cyg. Our multisite photometric campaign occurring 40 years post eruption covered 26-nights (2015-2017). The reflection effect from the heated donor has decreased, but still dominates the op- tical radiation with...
Article
Full-text available
The Jansky Very Large Array was used to observe 121 magnetic cataclysmic variables (MCVs). We report radio detections of 19 stars. Fourteen are new radio sources, increasing the number of MCVs that are radio sources by more than twofold, from 8 to 22. Most detections are at 8.7 GHz (X-band) with a lesser number at 5.4 and 21.1 GHz (C- and K-bands)....
Article
Full-text available
The types of instability in the interacting binary stars are reviewed. The project "Inter-Longitude Astronomy" is a series of smaller projects on concrete stars or groups of stars. It has no special funds, and is supported from resources and grants of participating organizations, when informal working groups are created. Totally we studied 1900+ va...
Conference Paper
We present the results of 3D magnetohydrodynamical simulations of the flow structure in a close binary system whose parameters correspond to those of the asynchronous polar BY Cam. The calculations’ results are given for 10 phases of the beat cycle between the white dwarf spin and the orbital frequencies. Our model takes account of the white dwarf’...
Article
Full-text available
We present new broad band optical photometry of two magnetic cataclysmic variable stars, the asynchronous polar BY Camelopardalis and the short period polar FL Ceti. Observations were obtained at the 2.1-m Otto Struve Telescope of McDonald Observatory with 3s and 1s integration times respectively. In an attempt to understand the observed complex ch...
Article
Full-text available
We present new optical observations of V1408 Aql (= 4U 1957+115), the only low mass X-ray binary, black hole candidate known to be in a persistently soft state. We combine new broadband optical photometry with previously published data and derive a precise orbital ephemeris. The optical light curves display sinusoidal variations modulated on the or...
Article
Full-text available
The remarkable discovery of many planets and candidates using the Kepler telescope even includes ten planets orbiting eight binaries. Three out of the eight, Kepler 16, Kepler 47, and KIC 9632895, have at least one planet in the circumbinary habitable zone (BHZ). In previous work (Mason et al. 2013), we investigated the potential habitability of Ea...
Article
Full-text available
Binaries could provide the best niches for life in the Galaxy. Although counterintuitive, this assertion follows directly from stellar tidal interaction theory and the evolution of lower mass stars. There is strong evidence that chromospheric activity of rapidly rotating young stars may be high enough to cause mass loss from atmospheres of potentia...
Article
Full-text available
We carry out high-speed photometry on 20 of the shortest-period, detached white dwarf binaries known and discover systems with eclipses, ellipsoidal variations (due to tidal deformations of the visible white dwarf), and Doppler beaming. All of the binaries contain low-mass white dwarfs with orbital periods less than 4 hr. Our observations identify...
Article
We present new broad-band optical photometry of the low mass X-ray binary (LMXB) UW CrB on four consecutive nights in June 2013. These data were obtained at the 2.1-m telescope of McDonald Observatory, with a time resolution of 10s, and cover a bit more than one orbital cycle each night. The light curves display partial eclipses of the accretion di...
Article
Limits on the potential habitability of exomoons orbiting massive planets within circumbinary habitable zones are examined. Exomoons orbiting planets in the habitable zones of single stars and those orbiting circumbinary planets are subject to the, sometimes intense, tidal heating of the planet. So, exomoon orbits need to be sufficiently large and...
Article
We present high speed optical photometry of the low mass X-ray binary V1727 Cygni. Simultaneous observations were obtained during five consecutive nights in 2013 using McDonald Observatory's 2.7-m and 2.1-m telescopes using u' and R filters respectively. There is very little variation in the u' intensity. The R data displays night to night and orbi...
Article
We present new high-speed broad-band optical photometry of the asynchronous polar (magnetic cataclysmic variable) BY Cam. Observations were obtained at the 2.1-m Otto Struve Telescope of McDonald observatory with 3s integration times. In an attempt to understand the complex changes in accretion flow geometry, we performed full 3D MHD simulations as...
Article
FL Ceti is a short period cataclysmic variable star belonging to the highly magnetic subclass of polars. Our one second time resolution light curves show dramatic eclipses, as well as a well defined ingress and egress features. We collected 35 hours of broad band optical photometry on FL Ceti at the 82" reflector in the McDonald Observatory. We obs...
Article
Full-text available
We report a mechanism capable of reducing (or increasing) stellar activity in binary stars, thereby potentially enhancing (or destroying) circumbinary habitability. In single stars, stellar aggression towards planetary atmospheres causes mass-loss, which is especially detrimental for late-type stars, because habitable zones are very close and activ...
Conference Paper
Full-text available
Progress towards understanding factors that contribute to habitability on planets in binary systems is summarized. In wide binaries, habitable zones (HZ) may contain so called S-type planets, a planet orbiting one of the stellar components. For most stable planetary orbits the HZ is dominated by the star being orbited, especially if it is the more...
Article
Full-text available
The number of planets found in binary systems is growing rapidly and the discovery of many more planets in binary systems appears inevitable. We use the newly refined and more restrictive, single star habitable zone (HZ) models of Kopparapu et al. (2013) and include planetary magnetic protection calculations in order to investigate binary star habi...
Article
Full-text available
High speed photometry of several accreting binaries was obtained using the McDonald Observatory 2.1m telescope and ARGOS CCD photometer. A broad-band filter (BVR) was used in order to maximize flux and maintain a short (1-10s) integration time on faint targets. Such observations obtained over several years allow for variability study over time scal...
Article
The black hole LMXB J1118+480 was observed using the Argos photometer on the 2.1 m telescope of McDonald Observatory on 30 nights from 2004 to 2012. Integration times were 10s and a broad-band (BVR) filter was used. All the light curves display a two-humped orbital modulation that has been interpreted as ellipsoidal variations. In addition, flicker...
Article
V1055 Orionis (=4U 0614+091) is thought to be an ultra-compact binary containing a neutron star primary with a white dwarf companion. High-speed (10s) broad-band optical observations using the McDonald Observatory, 2.1m, Otto Struve Telescope were obtained on 13 nights in 2010, 2011, and 2012. The nightly mean brightness remained quite stable over...
Article
Optical observations of the low-mass X-ray binary PSR J1023+0038 are presented. CCD photometry was collected with 10s integrations using the Argos camera on the 2.1 m Otto Struve Telescope of McDonald Observatory. Data was obtained during seven nights in February 2011 and January 2012. The light curves are quite similar to those obtained in previou...
Article
Full-text available
The optical light curve of the persistent low-mass X-ray binary V1408 Aquilae (= 4U 1957+115) has a sinusoidal modulation at the system's 9.33 h orbital period. We obtained new broadband high-speed optical photometry of V1408 Aql on five successive nights in 2012 July and another four nights in 2012 August. Its brightness varied from night to night...
Article
We investigate habitable niches, defined as locations with optimum conditions for complex life to exist. The recent discovery of planets in several binaries motivates this study to examine favorable habitability circumstances in both single and binary star systems. Stellar evolution calculations are used to model time dependent stellar luminosity,...
Article
We present photometric data on three cataclysmic variables. Broad-band CCD observations of FL Ceti, BY Cam, and DQ Her were obtained with 1-3s integrations at the Otto Struve, 2.1m, Telescope of McDonald Observatory. High speed optical photometry reveals details in these cataclysmic variables not possible using longer time integrations. In FL Ceti,...
Article
Full-text available
We performed 3D MHD calculations of stream accretion in cataclysmic variable stars for which the white dwarf primary star possesses a strong and complex magnetic field. These calculations are motivated by observations of polars; cataclysmic variables containing white dwarfs with magnetic fields sufficiently strong to prevent the formation of an acc...
Article
Full-text available
We present new optical photometry of two low-mass X-ray binary stars, UW CrB (MS 1603+260) and V1408 Aql (4U 1957+115). UW CrB is an eclipsing binary and we refine its eclipse ephemeris and measure an upper limit to the rate of change of its orbital period, | P-dot | < 4.2 Multiplication-Sign 10{sup -11} (unitless). The light curve of UW CrB shows...
Article
Recent results of high speed (1-5s) photometry of interacting binaries are presented. These include a study of 33 optically reprocessed X-ray bursts from UW CrB, reveling bursts at all orbital phases except during partial eclipses of the accretion disk. Ellipsoidal variations are observed in the LMXBs V1727 Cygni and J1118+480 providing multi-year...
Article
Thanks to the Kepler telescope, and other efforts, the number of known exoplanets has dramatically increased. Detections include planets in binary star systems. The presence of a planet in the habitable zone of a star, or a binary star, is a necessary but not sufficient condition for complex life; which may be quite restrictive, e.g. Ward and Brown...
Article
We present optical observations of the black hole X-ray binary J1118+480 obtained, on 12 nights during 2010 and a single night in June 2011, using the McDonald Observatory 2.1-m Otto Struve Telescope and Argos photometer using a BVR filter. J1118+480 is an X-ray transient currently in quiescence. A period study yields a period of P = 0.08496672 +/-...
Article
We present optical observations of the black hole candidate LMXB SWIFT J1753.4-0126 with the 2.1m Otto Struve Telescope of McDonald Observatory. The Argos CCD photometer was used and 10s integrations were obtained on 19 nights in 2010 and 2011. We performed a period search using a Phase Dispersion Minimization (PDM) code and we obtain a period of 3...
Article
We report the first detection of ellipsoidal variations in the quiescent low mass X-ray binary, V1727 Cygni. We obtained 10s integrations over 19 nights during 2010-2011, with 1 orbital period observed each night using the 82in, Otto Struve Telescope, of McDonald Observatory. A power spectrum analysis detected a signal at 1/2 of the orbital period...
Article
We have obtained FUV spectroscopy of the X-ray binaries A0620-00, 4U0614+091, and MS1603.6+2600 using the Cosmic Origins Spectrograph on HST. The UV observations have been accompanied by contemporaneous multiwavelength X-ray, optical/NIR, and (for A0620-00) radio observations. The data provide constraints on the structure of the accretion disk and...
Article
V1408 Aql is a low-mass X-ray binary with an orbital period of 9.329 hrs. Its optical orbital light curve has previously been measured by Thorstensen (1987), who found a sinusoidal modulation that he attributed to the irradiated face of the secondary star; and it has been measured by Hakala et al. (1999), who, based on their much smaller but multic...
Article
We performed 3-D MHD calculations of stream accretion in magnetic cataclysmic variable stars (mCVs). Specifically, we simulate accretion flow onto a white dwarf possessing a strong and complex magnetic field which dominates the accretion flow and prevents the formation of an accretion disk. These calculations are motivated by observations that some...
Article
Starting in the summer of 2010 and continuing to the summer of 2011, we observed J1118+480 at McDonald Observatory using Argos (a charged-coupled device, CCD, camera) for a total of 13 nights. We present the light curves from the gathered nights that have been reduced using scientific linex operating system and IRAF. The light curve data is convert...
Article
We conducted optical observations of the black hole candidate J1753.4-0126 with the 82 inch (2.1 m) Otto Struve Telescope at the McDonald Observatory. A total of 20 nights of data were collected from May 2010 through June 2011. Data was reduced using the Interactive Reduction and Analysis Facility (IRAF). We present the resulting light curves. We d...
Article
This research is based upon optical observations of the neutron star V1727 Cygni (=4U 2129+47). A total of 19 nights of data were collected from September 2010 through August 2011 at the McDonald Observatory via the 82 inch (2.1 m) Otto Struve Telescope. The Interactive Reduction and Analysis Facility (IRAF) was used to reduce the data collected. W...
Article
Full-text available
V1408 Aql (= 4U 1957+115) is a low-mass X-ray binary with an orbital period near 9.3 hr, whose compact star is a black hole candidate. The system shows a large-amplitude orbital photometric modulation at optical wavelengths. We have obtained new optical photometry of V1408 Aql from which we derive the orbital light curve and an improved orbital eph...
Article
Full-text available
We conducted a VLA survey of nine magnetic cataclysmic variable stars (MCVs) at 8.436 GHz in 2003 October, to constrain models of radio emission. A follow-up study was conducted in 2004 September. We obtained the first radio detections of AR UMa, the MCV with the highest known magnetic field (230 MG), at flux densities of 0.422 ± 0.060 mJy (2003 Oc...
Article
Full-text available
We present CCD photometry of the low-mass X-ray binary UW Coronae Borealis (UW CrB). Its light curve shows eclipses at a period near 111 minutes, but the eclipses vary in depth and shape and often disappear. Restricting our analysis to the deeper eclipses, we find the orbital period to be 110:976722 AE 0:000012 minutes, but the times of mideclipse...