Publications (46)
Citizen CATE 2024: Extending Totality During the 8 April 2024 Total Solar Eclipse with a Distributed Network of Community Participants
Sarah A. Kovac, Amir Caspi, Daniel B. Seaton +240
The Citizen CATE 2024 next-generation experiment placed 43 identical telescope and camera setups along the path of totality during the total solar eclipse (TSE) on 8 April 2024 to…
The Occurrence of Non-Pulsating Stars in the gamma Dor and delta Sct Pulsation Instability Regions: Results from Kepler Quarter 14-17 Data
Joyce A. Guzik, Paul A. Bradley, Jason Jackiewicz +3
In our 2013 Astronomical Review article, we discussed the statistics of variability for 633 faint spectral type A-F stars observed by the Kepler spacecraft during Quarters 6-13. We…
Inferring the Solar Meridional Circulation Flow Profile by Applying Bayesian Methods to Time-distance Helioseismology
Aleczander Herczeg, Jason Jackiewicz
Mapping the large-scale subsurface plasma flow profile within the Sun has been attempted using various methods for several decades. One such flow in particular is the meridional ci…
A Possible Mechanism for Driving Oscillations in Hot Giant Planets
Ethan Dederick, Jason Jackiewicz
The -mechanism has been successful in explaining the origin of observed oscillations of many types of "classical" pulsating variable stars. Here we examine quantitatively if th…
Variable Blue Straggler Stars in Open Cluster NGC 6819 Observed in the Kepler 'Superstamp' Field
Joyce A. Guzik, Andrzej S. Baran, Sachu Sanjayan +4
NGC 6819 is an open cluster of age 2.4 Gyr that was in the NASA Kepler spacecraft field of view from 2009 to 2013. The central part of the cluster was observed in a 200 x 200 pixel…
Data Analysis of Bright Main-Sequence A- and B-type Stars Observed Using the TESS and BRITE Spacecraft
Joyce A. Guzik, Jason Jackiewicz, Andrzej Pigulski +5
During the last two years we have received long time-series photometric observations of bright (V mag < 8) main-sequence A- and B-type stars observed by the NASA TESS spacecraft an…
Quantum fluctuation driven first order phase transition in weak ferromagnetic metals
Jason Jackiewicz, Kevin S. Bedell
In a local Fermi liquid (LFL), we show that there is a line of weak first order phase transitions between the ferromagnetic and paramagnetic phases due to purely quantum fluctuatio…
Many body exchange effects close to the s-wave Feshbach resonance in two-component Fermi systems: Is a triplet superfluid possible?
Sergio Gaudio, Jason Jackiewicz, Kevin S. Bedell
We suggest that the exchange fluctuations close to a Feshbach resonance in a two-component Fermi gas can result in an effective p-wave attractive interaction. On the BCS side of a…
The Origin of Sequential Chromospheric Brightenings
Michael S. Kirk, K. S. Balasubramaniam, Jason Jackiewicz +1
Sequential chromospheric brightenings (SCBs) are often observed in the immediate vicinity of erupting flares and are associated with coronal mass ejections. Since their initial dis…
Three-dimensional atmospheric dynamics of Jupiter from ground-based Doppler imaging spectroscopy in the visible
François-Xavier Schmider, Patrick Gaulme, Raúl Morales-JuberÃas +25
We present three-dimensional (3D) maps of Jupiter's atmospheric circulation at cloud-top level from Doppler-imaging data obtained in the visible domain with JIVE, the second node o…
Deneb and the alpha Cygni Variables
Joyce A. Guzik, Brian Kloppenborg, Jason Jackiewicz
Deneb, the prototype alpha Cygni variable, is a blue-white supergiant that shows irregular variability with quasi-period around 12 days in brightness and radial velocity. Abt et al…
Fermi liquid behavior and Luttinger's theorem close to a diverging scattering length
Sergio Gaudio, Jason Jackiewicz, Kevin S. Bedell
Based on the results obtained in a previous paper (S. Gaudio et al., cond-mat/0505309}, we derive the thermodynamic properties of a Fermi gas, deep into the quantum degenerate regi…
Validation of Spherical Born Approximation Sensitivity Functions for Measuring Deep Solar Meridional Flow
Vincent G. A. Böning, Markus Roth, Jason Jackiewicz +1
Accurate measurements of deep solar meridional flow are of vital interest for understanding the solar dynamo. In this paper, we validate a recently developed method for obtaining s…
Challenges in Cepheid Evolution and Pulsation Modeling
Joyce A. Guzik, Jason Jackiewicz, Nancy R. Evans
Cepheids have long been used as standard candles to determine distances around the Milky Way and to nearby galaxies. A discrepancy still remains for Hubble Constant determinations…
Multi-Height Observations of Atmospheric Gravity Waves at Solar Disk Center
Oana Vesa, Jason Jackiewicz, Kevin Reardon
Atmospheric gravity waves (AGWs) are low-frequency, buoyancy-driven waves that are generated by turbulent convection and propagate obliquely throughout the solar atmosphere. Their…
Characterizing Variability in Bright Metallic-Line A (Am) Stars Using Data from the NASA TESS Spacecraft
Joyce Ann Guzik, Jason Jackiewicz, Giovanni Catanzaro +1
Metallic-line A (Am) stars are main-sequence stars of around twice the mass of the Sun that show element abundance peculiarities in their spectra. The radiative levitation and diff…
A model for coexistent superconductivity and ferromagnetism
Jason Jackiewicz, Krastan B. Blagoev, Kevin S. Bedell
We explore various temperature dependencies and thermodynamic quantities of a mean field model of a ferromagnetic-superconducting system. The starting point for this model is based…
Amplitude Variability in gamma Dor and delta Scuti stars observed by the Kepler Spacecraft
Joyce A. Guzik, Katie Kosak, Paul A. Bradley +1
The NASA Kepler spacecraft data revealed a large number of multimode nonradially pulsating gamma Dor and delta Sct variable star candidates. The high precision long time-series pho…
Alpha Cygni Variables as Seen from the Transiting Exoplanet Survey Satellite
Joyce A. Guzik, Claire Whitley, Nova Moore +2
The Alpha Cygni (ACYG) variables are blue-white supergiants which display low-amplitude brightness variations of around 0.1 magnitude. The prototype Deneb shows quasi-periodic vari…
APOGEE/Kepler Overlap Yields Orbital Solutions for a Variety of Eclipsing Binaries
Joni Marie Clark Cunningham, Meredith L. Rawls, Diana Windemuth +4
Spectroscopic Eclipsing Binaries (SEBs) are fundamental benchmarks in stellar astrophysics and today are observed in breathtaking detail by missions like TESS, Kepler, and APOGEE.…
Abrupt Pulsation Resumptions in Deneb: An Update
Joyce A. Guzik, Brian Kloppenborg, Noel Richardson +4
Deneb, the prototype Alpha Cygni variable, is a bright A2 Ia supergiant which shows irregular variability with a 12-day quasi-period, presumed to be caused by pulsations. At the 20…
An Analysis of Stochastic Jovian Oscillation Excitation by Moist Convection
Ethan Dederick, Jason Jackiewicz, Tristan Guillot
Recent observations of Jupiter have suggested the existence of global oscillatory modes at millihertz frequencies, yet the source mechanism responsible for driving these modes is s…
Properties of Sequential Chromospheric Brightenings and Associated Flare Ribbons
Michael S. Kirk, K. S. Balasubramaniam, Jason Jackiewicz +2
We report on the physical properties of solar sequential chromospheric brightenings (SCBs) observed in conjunction with moderate-sized chromospheric flares with associated CMEs. To…
Qualities of Sequential Chromospheric Brightenings Observed in Optical and UV Images
Michael S. Kirk, K. S. Balasubramaniam, Jason Jackiewicz +1
Chromospheric flare ribbons observed in H-alpha appear well-organized when first examined: ribbons impulsively brighten, morphologically evolve, and exponentially decay back to pre…
Results of a Search for gamma Dor and delta Sct Stars with the Kepler Spacecraft
Paul A. Bradley, Joyce A. Guzik, Lillian F. Miles +3
The light curves of 2768 stars with effective temperatures and surface gravities placing them near the gamma Doradus/delta Scuti instability region were observed as part of the Kep…
KIC 9246715: The Double Red Giant Eclipsing Binary With Odd Oscillations
Meredith L. Rawls, Patrick Gaulme, Jean McKeever +7
We combine Kepler photometry with ground-based spectra to present a comprehensive dynamical model of the double red giant eclipsing binary KIC 9246715. While the two stars are very…
Meridional Flow in the Solar Convection Zone I: Measurements from GONG Data
Shukur Kholikov, Alexander Serebryanskiy, Jason Jackiewicz
Large-scale plasma flows in the Sun's convection zone likely play a major role in solar dynamics on decadal timescales. In particular, quantifying meridional motions is a critical…
The Sunspot Solar Observatory Data Archive: Continuing Operations at the Dunn Solar Telescope
Sean G. Sellers, Juie Shetye, Damian J. Christian +9
The Sunspot Solar Observatory Data Archive (SSODA) stores data acquired with the suite of instruments at the Richard B. Dunn Solar Telescope (DST) from February 2018 to the present…
Pairing symmetry signatures of T1 in superconducting ferromagnets
Hari P. Dahal, Jason Jackiewicz, Kevin S. Bedell
We study the nuclear relaxation rate 1/T1 as a function of temperature for a superconducting-ferromagnetic coexistent system using a p-wave triplet model for the superconducting pa…
Apache Point Observatory follow-up of ACcelerating Candidate ExopLanet host Stars (APO ACCELS): Ages for 166 Accelerating Stars in the Northern Hemisphere
Anne E. Peck, Eric L. Nielsen, Robert J. De Rosa +14
Directly imaged substellar companions with well-constrained ages and masses serve as vital empirical benchmarks for planet formation and evolution models. Potential benchmark compa…
Superfluid (Amplitude) Fluctuations Above in a Unitary Fermi Gas
Hua Li, Jason Jackiewicz, Kevin S. Bedell
We study the transport properties of a Fermi gas with strong attractive interactions close to the unitary limit. In particular, we compute the spin diffusion lifetime of the Fermi…
Exploring Jupiter's Polar Deformation Lengths with High Resolution Shallow Water Modeling
Ali Hyder, Wladimir Lyra, Nancy Chanover +2
The polar regions of Jupiter host a myriad of dynamically interesting phenomena including vortex configurations, folded-filamentary regions (FFRs), and chaotic flows. Juno observat…
The Classificiation of Kepler B star Variables
Bernard J. McNamara, Jason Jackiewicz, Jean McKeever
The light curves of 252 B-star candidates in the Kepler data base are analyzed in a similar fashion to that done by Balona et al. (2011) to further characterize B star variability,…
Atmospheric Gravity Waves Modulated by the Magnetic Field Configuration
Oana Vesa, Julio Morales, Jason Jackiewicz +2
Atmospheric gravity waves (AGWs) are buoyancy-driven waves excited by turbulent convection and contribute to the dynamics and energy transport of the lower solar atmosphere. We pre…
Relationships Between Sequential Chromospheric Brightening and the Corona
Michael S. Kirk, K. S. Balasubramaniam, Jason Jackiewicz +1
The chromosphere is a complex region that acts as an intermediary between the magnetic flux emergence in the photosphere and the magnetic features seen in the corona. Large eruptio…
Red Giants in Eclipsing Binary and Multiple-Star Systems: Modeling and Asteroseismic Analysis of 70 Candidates from Kepler Data
Patrick Gaulme, Jean Mc Keever, Meredith L. Rawls +3
Red-giant stars are an incredible source of information for testing models of stellar evolution, as asteroseismology has opened up a window into their interiors. Such insights are…
Testing the asteroseismic scaling relations for Red Giants with Eclipsing Binaries Observed by Kepler
Patrick Gaulme, Jean McKeever, Jason Jackiewicz +7
Given the potential of ensemble asteroseismology for understanding fundamental properties of large numbers of stars, it is critical to determine the accuracy of the scaling relatio…
Surface Activity and Oscillation Amplitudes of Red Giants in Eclipsing Binaries
Patrick Gaulme, Jason Jackiewicz, Thierry Appourchaux +1
Among 19 red-giant stars belonging to eclipsing binary systems that have been identified in Kepler data, 15 display solar-like oscillations. We study whether the absence of mode de…
Active red giants: close binaries versus single rapid rotators
Patrick Gaulme, Jason Jackiewicz, Federico Spada +7
The objective of this work is to determine what fraction of red-giant (RG) stars shows photometric rotational modulation, and understand its origin. One of the underlying questions…
Inversions for Deep Solar Meridional Flow Using Spherical Born Kernels
Vincent G. A. Böning, Markus Roth, Jason Jackiewicz +1
The solar meridional flow is a crucial ingredient in modern dynamo theory. Seismic estimates of this flow have, however, been contradictory in deeper layers below about $0.9\,R_\od…
Astro2020 Science White Paper: Stellar Physics and Galactic Archeology using Asteroseismology in the 2020's
Daniel Huber, Sarbani Basu, Paul Beck +32
Asteroseismology is the only observational tool in astronomy that can probe the interiors of stars, and is a benchmark method for deriving fundamental properties of stars and exopl…
Physical properties of ferromagnetic-superconducting coexistent system
Hari P. Dahal, Jason Jackiewicz, Kevin S. Bedell
We studied the nuclear relaxation rate 1/T1 of a ferromagnetic-superconducting system from the mean field model proposed in Ref.14. This model predicts the existence of a set of ga…
Abrupt Periodic Pulsation Resumptions in Deneb
Joyce A. Guzik, Helmut A. Abt, Jason Jackiewicz +1
Deneb (alpha Cygni) is a bright (V magnitude 1.25) blue-white supergiant (spectral type A2 Ia) which shows variability in both radial velocity and photometric measurements. H. Abt…
Seismology of Giant Planets
Patrick Gaulme, Benoit Mosser, Francois-Xavier Schmider +2
Seismology applied to giant planets could drastically change our understanding of their deep interiors, as it has happened with the Earth, the Sun, and many main-sequence and evolv…
Probabilistic Inversions for Time-Distance Helioseismology
Jason Jackiewicz
Time-distance helioseismology is a set of powerful tools to study features below the Sun's surface. Inverse methods are needed to interpret time-distance measurements, with many ex…
Sequential Chomospheric Brightening: An Automated Approach to Extracting Physics from Ephemeral Brightening
Michael S. Kirk, K. S. Balasubramaniam, Jason Jackiewicz +2
We make a comparison between small scale chromospheric brightenings and energy release processes through examining the temporal evolution of sequential chromospheric brightenings (…