Publications (109)
Hot super-Earths stripped by their host stars
M. S. Lundkvist, H. Kjeldsen, S. Albrecht +26
Simulations predict that hot super-Earth sized exoplanets can have their envelopes stripped by photo-evaporation, which would present itself as a lack of these exoplanets. However,…
A fast-rotating pear-shaped nucleus
A. Karmakar, P. Datta, Soumik Bhattacharya +15
The spectroscopic studies have identified few Actinide and Lanthanide nuclei of the periodic table, which can assume the pear shape. The low frequency collective rotation of these…
Limits on surface gravities of Kepler planet-candidate host stars from non-detection of solar-like oscillations
T. L. Campante, W. J. Chaplin, M. N. Lund +20
We present a novel method for estimating lower-limit surface gravities log g of Kepler targets whose data do not allow the detection of solar-like oscillations. The method is teste…
Helioseismic analysis of the hydrogen partition function in the solar interior
S. Basu, W. Dappen, A. Nayfonov
The difference in the adiabatic gradient gamma_1 between inverted solar data and solar models is analyzed. To obtain deeper insight into the issues of plasma physics, the so-called…
Kepler White Paper: Asteroseismology of Solar-Like Oscillators in a 2-Wheel Mission
W. J Chaplin, H. Kjeldsen, J. Christensen-Dalsgaard +53
We comment on the potential for continuing asteroseismology of solar-type and red-giant stars in a 2-wheel Kepler Mission. Our main conclusion is that by targeting stars in the ecl…
A large sample of calibration stars for Gaia: log g from Kepler and CoRoT
O. L. Creevey, F. Thévenin, S. Basu +6
Asteroseismic data can be used to determine surface gravities with precisions of < 0.05 dex by using the global seismic quantities Deltanu and nu_max along with Teff and [Fe/H]. Su…
Verification of the Kepler Input Catalog from Asteroseismology of Solar-type Stars
G. A. Verner, W. J. Chaplin, S. Basu +25
We calculate precise stellar radii and surface gravities from the asteroseismic analysis of over 500 solar-type pulsating stars observed by the Kepler space telescope. These physic…
The asteroseismic potential of Kepler: first results for solar-type stars
W. J. Chaplin, T. Appourchaux, Y. Elsworth +105
We present preliminary asteroseismic results from Kepler on three G-type stars. The observations, made at one-minute cadence during the first 33.5d of science operations, reveal hi…
Kepler Asteroseismology Program: Introduction and First Results
Ronald L. Gilliland, T. M. Brown, J. Christensen-Dalsgaard +32
Asteroseismology involves probing the interiors of stars and quantifying their global properties, such as radius and age, through observationsof normal modes of oscillation. The te…
KOI-3158: The oldest known system of terrestrial-size planets
T. L. Campante, T. Barclay, J. J. Swift +38
The first discoveries of exoplanets around Sun-like stars have fueled efforts to find ever smaller worlds evocative of Earth and other terrestrial planets in the Solar System. Whil…
Low-period spacing core-helium burning giants: `hot subdwarf analogues'?
S. Hekker, Y. Elsworth, T. A. M. Braun +1
Global stellar oscillations probe the internal structure of stars. In low- to intermediate-mass red giants, these oscillations provide signatures from both the outer regions of the…
PLATO as it is: a legacy mission for Galactic archaeology
A. Miglio, C. Chiappini, B. Mosser +102
Deciphering the assembly history of the Milky Way is a formidable task, which becomes possible only if one can produce high-resolution chrono-chemo-kinematical maps of the Galaxy.…
Structure of the solar core: Effect of asymmetry of peak profiles
S. Basu, S. Turck-Chieze, G. Berthomieu +7
Recent studies have established that peaks in solar oscillation power spectra are not Lorentzian in shape, but have a distinct asymmetry. Fitting a symmetric Lorentzian profile to…
Emerging interfacial magnetization in isovalent manganite heterostructures driven by octahedral coupling
Yogesh Kumar, Harsh Bhatt, S. Kakkar +7
The distortion of corner-sharing octahedra in isovalent perovskite transition-metal oxide interfaces is proven to be an excellent way to tailor the electronic and magnetic properti…
Extended self-similarity of atmospheric boundary layer wind fields in mesoscale regime: Is it real?
V. P. Kiliyanpilakkil, S. Basu
In this letter, we study the scaling properties of multi-year observed and atmospheric model-generated wind time series. We have found that the extended self-similarity holds for t…
Solar-like oscillations in cluster stars
D. Stello, S. Basu, T. R. Bedding +21
We present a brief overview of the history of attempts to obtain a clear detection of solar-like oscillations in cluster stars, and discuss the results on the first clear detection…
Ensemble Asteroseismology of Solar-Type Stars with the NASA Kepler Mission
W. J. Chaplin, H. Kjeldsen, J. Christensen-Dalsgaard +56
In addition to its search for extra-solar planets, the NASA Kepler Mission provides exquisite data on stellar oscillations. We report the detections of oscillations in 500 solartyp…
'Rapid fire' spectroscopy of Kepler solar-like oscillators
A. O. Thygesen, H. Bruntt, W. J. Chaplin +1
The NASA Kepler mission has been continuously monitoring the same field of the sky since the successful launch in March 2009, providing high-quality stellar lightcurves that are ex…
Asteroseismology of Solar-type Stars with Kepler I: Data Analysis
C. Karoff, W. J. Chaplin, T. Appourchaux +46
We report on the first asteroseismic analysis of solar-type stars observed by Kepler. Observations of three G-type stars, made at one-minute cadence during the first 33.5d of scien…
The Asteroseismic Target List (ATL) for solar-like oscillators observed in 2-minute cadence with the Transiting Exoplanet Survey Satellite (TESS)
M. Schofield, W. J. Chaplin, D. Huber +21
We present the target list of solar-type stars to be observed in short-cadence (2-min) for asteroseismology by the NASA Transiting Exoplanet Survey Satellite (TESS) during its 2-ye…
Asteroseismology of solar-type stars with K2
W. J. Chaplin, M. N. Lund, R. Handberg +44
We present the first detections by the NASA K2 Mission of oscillations in solar-type stars, using short-cadence data collected during K2 Campaign\,1 (C1). We understand the asteros…
Ages and fundamental properties of Kepler exoplanet host stars from asteroseismology
V. Silva Aguirre, G. R. Davies, S. Basu +21
We present a study of 33 {\it Kepler} planet-candidate host stars for which asteroseismic observations have sufficiently high signal-to-noise ratio to allow extraction of individua…
Super-Nyquist asteroseismology of solar-like oscillators with Kepler and K2 - expanding the asteroseismic cohort at the base of the red-giant branch
W. J. Chaplin, Y. Elsworth, G. R. Davies +4
We consider the prospects for detecting solar-like oscillations in the "super-Nyquist" regime of long-cadence (LC) Kepler photometry, i.e., above the associated Nyquist frequency o…
Asteroseismic fundamental properties of solar-type stars observed by the NASA Kepler Mission
W. J. Chaplin, S. Basu, D. Huber +32
We use asteroseismic data obtained by the NASA Kepler Mission to estimate the fundamental properties of more than 500 main-sequence and sub-giant stars. Data obtained during the fi…
A uniform asteroseismic analysis of 22 solar-type stars observed by Kepler
S. Mathur, T. S. Metcalfe, M. Woitaszek +39
Asteroseismology with the Kepler space telescope is providing not only an improved characterization of exoplanets and their host stars, but also a new window on stellar structure a…
Magnetic Activity Cycles in the Exoplanet Host Star epsilon Eridani
T. S. Metcalfe, A. P. Buccino, B. P. Brown +7
The active K2 dwarf epsilon Eri has been extensively characterized, both as a young solar analog and more recently as an exoplanet host star. As one of the nearest and brightest st…
Nonlinear Hydromagnetic Wave Support of a Stratified Molecular Cloud
T. Kudoh, S. Basu
We perform numerical simulations of nonlinear MHD waves in a gravitationally stratified molecular cloud that is bounded by a hot and tenuous external medium. We study the relation…
Effect of size and aspect ratio on structural parameters and evidence of shape transition in zinc oxide nanostructures
Manoranjan Ghosh, Debjani Karmakar, S. Basu +4
Dependence of structural parameters on the size of nanoparticles is a topic of general interest where the effect of shape is often neglected. We report a comprehensive study on siz…
Adjoint for Operators in Banach Spaces
T. L. Gill, S. Basu, W. W. Zachary +1
In this paper we show that a result of Gross and Kuelbs, used to study Gaussian measures on Banach spaces, makes it possible to construct an adjoint for operators on separable Bana…
Redshift Limits of BL Lacertae Objects from Optical Spectroscopy
J. D. Finke, J. C. Shields, M. Boettcher +1
Context: BL Lacertae objects have been the targets for numerous recent multiwavelength campaigns, continuum spectral variability studies, and theoretical spectral and variability m…
Activity Cycles of Southern Asteroseismic Targets
T. S. Metcalfe, P. G. Judge, S. Basu +4
The Mount Wilson Ca HK survey revealed magnetic activity variations in a large sample of solar-type stars with timescales ranging from 2.5 to 25 years. This broad range of cycle pe…
Measurement of the Hoyle State Radiative Transition Width
T. K. Rana, Deepak Pandit, S. Manna +30
The radiative decay of the Hoyle state is the doorway to the production of heavier elements in stellar environment. Here we report, an exclusive measurement of electric quadruple (…
Stellar ages and convective cores in field main-sequence stars: first asteroseismic application to two Kepler targets
V. Silva Aguirre, S. Basu, I. M. Brandão +21
Using asteroseismic data and stellar evolution models we make the first detection of a convective core in a Kepler field main-sequence star, putting a stringent constraint on the t…
Oscillation frequencies for 35 \Kepler solar-type planet-hosting stars using Bayesian techniques and machine learning
G. R. Davies, V. Silva Aguirre, T. R. Bedding +16
\Kepler has revolutionised our understanding of both exoplanets and their host stars. Asteroseismology is a valuable tool in the characterisation of stars and \Kepler is an excelle…
Physical properties and electrochemical performance of Zn-substituted NaMnZnO nanostructures as cathode in Na-ion batteries
Mahesh Chandra, Rishabh Shukla, Rakesh Saroha +4
We report the synthesis, physical properties and electrochemical performance of Zn substituted NaMnZnO ( 0 -- 0.02) nanostructures as cathode in Na-ion…
Parametrizing the time-variation of the "surface term" of stellar p-mode frequencies: application to helioseismic data
R. Howe, S. Basu, G. R. Davies +4
The solar-cyle variation of acoustic mode frequencies has a frequency dependence related to the inverse mode inertia. The discrepancy between model predictions and measured oscilla…
Evolutionary influences on the structure of red-giant acoustic oscillation spectra from 600d of Kepler observations
T. Kallinger, S. Hekker, B. Mosser +12
Context: The Kepler space mission is reaching continuous observing times long enough to start studying the fine structure of the observed p-mode spectra. Aims: In this paper, we ai…
Current State of Astrophysical Opacities: A White Paper
A. E. Lynas-Gray, S. Basu, M. A. Bautista +5
Availability of reliable atomic and molecular opacity tables is essential in a wide variety of astronomical modeling: the solar and stellar interiors, stellar and planetary atmosph…
Local helioseismology of sunspot regions: comparison of ring-diagram and time-distance results
A. G. Kosovichev, S. Basu, R. Bogart +10
Local helioseismology provides unique information about the subsurface structure and dynamics of sunspots and active regions. However, because of complexity of sunspot regions loca…
Solar-cycle variation of the sound-speed asphericity from GONG and MDI data 1995-2000
H. M. Antia, S. Basu, F. Hill +3
We study the variation of the frequency splitting coefficients describing the solar asphericity in both GONG and MDI data, and use these data to investigate temporal sound-speed va…
Helioseismology of Sunspots: A Case Study of NOAA Region 9787
L. Gizon, H. Schunker, C. S. Baldner +12
Various methods of helioseismology are used to study the subsurface properties of the sunspot in NOAA Active Region 9787. This sunspot was chosen because it is axisymmetric, shows…
Evidence of Formation of Superdense Nonmagnetic Cobalt
Nasrin Banu, Surendra Singh, B. Satpati +6
Magnetism of 3d transition metals at high density has always received wide interest due to existence of magnetism at the core of the Earth. For ferromagnetic cobalt, although there…
Constructing a one-solar-mass evolutionary sequence using asteroseismic data from \textit{Kepler}
V. Silva Aguirre, W. J. Chaplin, J. Ballot +39
Asteroseismology of solar-type stars has entered a new era of large surveys with the success of the NASA \textit{Kepler} mission, which is providing exquisite data on oscillations…
A precise asteroseismic age and radius for the evolved Sun-like star KIC 11026764
T. S. Metcalfe, M. J. P. F. G. Monteiro, M. J. Thompson +55
The primary science goal of the Kepler Mission is to provide a census of exoplanets in the solar neighborhood, including the identification and characterization of habitable Earth-…
Amplitudes of solar-like oscillations: constraints from red giants in open clusters observed by Kepler
D. Stello, D. Huber, T. Kallinger +20
Scaling relations that link asteroseismic quantities to global stellar properties are important for gaining understanding of the intricate physics that underpins stellar pulsation.…
Asteroseismology of red giants from the first four months of Kepler data: Fundamental parameters
T. Kallinger, B. Mosser, S. Hekker +18
Clear power excess in a frequency range typical for solar-type oscillations in red giants has been detected in more than 1000 stars, which have been observed during the first 138 d…
An ancient extrasolar system with five sub-Earth-size planets
T. L. Campante, T. Barclay, J. J. Swift +38
The chemical composition of stars hosting small exoplanets (with radii less than four Earth radii) appears to be more diverse than that of gas-giant hosts, which tend to be metal-r…
Accurate parameters of 93 solar-type Kepler targets
H. Bruntt, S. Basu, B. Smalley +29
We present a detailed spectroscopic study of 93 solar-type stars that are targets of the NASA/Kepler mission and provide detailed chemical composition of each target. We find that…
Asteroseismology of delta Scuti stars - a parameter study and application to seismology of FG Virginis
M. R. Templeton, S. Basu, P. Demarque
We assess the potential of asteroseismology for determining the fundamental properties of individual Scuti stars. We computed a grid of evolution and adiabatic pulsation model…
Superconductivity-driven magnetization modulation in YBa2Cu3O7-δ /SrTiO3/La0.67Sr0.33MnO3 heterostructures
Surendra Singh, Harsh Bhatt, Yogesh Kumar +6
Using spin polarized neutron reflectivity experiments, we demonstrate an unusual proximity behaviour when the superconductor (SC) and the ferromagnet (FM) are coupled through an in…
Antiferromagnetic Coupling between Surface and Bulk Magnetization and Anomalous Magnetic Transport in Electro-deposited Co Film
Surendra Singh, C. L. Prajapat, D. Bhattacharya +3
We report an interesting magnetic behavior of a Co film (thickness ~ 350 Ã ) grown on Si/Ti/Cu buffer layer by electro-deposition (ED) technique. Using depth sensitive X-ray reflec…
Antisymmetric magnetoresistance and helical magnetic structure in compensated Gd/Co multilayer
Surendra Singh, M. A. Basha, C. L. Prajapat +8
Using spin dependent specular and off-specular polarized neutron reflectivity (PNR), we report the observation of a twisted helical magnetic structure with planar 2Ï domain wall (…
Non-Gaussianity from Features
S. Basu, D. J. Brooker, N. C. Tsamis +1
The strongest non-Gaussianity in single-scalar potential models of inflation is associated with features in the power spectrum. We stress the importance of accurately modelling the…
A novel alternative to analyzing multiple choice questions via discrimination index
P. K. Joshi, Y. Jain, R. Khunyakari +1
The value of multiple choice questions (MCQs) in seeking large-scale, high-stakes, educational assessment is widely established. Students' responses to test items with a multiple-c…
Changes in the sensitivity of solar p-mode frequency shifts to activity over three solar cycles
R. Howe, W. J. Chaplin, G. R. Davies +3
Low-degree solar p-mode observations from the long-lived Birmingham Solar Oscillations Network (BiSON) stretch back further than any other single helioseismic data set. Results fro…
The robustness of inferred envelope and core rotation rates of red-giant stars from asteroseismology
F. Ahlborn, E. P. Bellinger, S. Hekker +2
Rotation is an important, yet poorly-modelled phenomenon of stellar structure and evolution. Accurate estimates of internal rotation rates are therefore valuable for constraining s…
SpaceInn hare-and-hounds exercise: Estimation of stellar properties using space-based asteroseismic data
D. R. Reese, W. J. Chaplin, G. R. Davies +15
Context: Detailed oscillation spectra comprising individual frequencies for numerous solar-type stars and red giants are or will become available. These data can lead to a precise…
Rotation of pear-shaped Ru nucleus
A. Karmakar, P. Datta, Soumik Bhattacharya +14
Atomic nuclei in general can have deformed shapes and nearly all these shapes are symmetric with respect to reflection. Only a few Actinide nuclei have stable reflection asymmetric…
Improved asteroseismic inversions for red-giant surface rotation rates
F. Ahlborn, E. P. Bellinger, S. Hekker +2
Asteroseismic observations of internal stellar rotation have indicated a substantial lack of angular momentum transport in theoretical models of subgiant and red-giant stars. Accur…
The Sun in transition? Persistence of near-surface structural changes through Cycle 24
R. Howe, G. R. Davies, W. J. Chaplin +5
We examine the frequency shifts in low-degree helioseismic modes from the Birmingham Solar-Oscillations Network (BiSON) covering the period from 1985 - 2016, and compare them with…
Predicting the detectability of oscillations in solar-type stars observed by Kepler
W. J. Chaplin, H. Kjeldsen, T. R. Bedding +49
Asteroseismology of solar-type stars has an important part to play in the exoplanet program of the NASA Kepler Mission. Precise and accurate inferences on the stellar properties th…
Asteroseismic sensitivity to internal rotation along the red-giant branch
F. Ahlborn, E. P. Bellinger, S. Hekker +2
Transport of angular momentum in stellar interiors is currently not well understood. Asteroseismology can provide us with estimates of internal rotation of stars and thereby advanc…
PLATO Hare-and-Hounds exercise: Asteroseismic model fitting of main-sequence solar-like pulsators
M. S. Cunha, I. W. Roxburgh, V. Aguirre Børsen-Koch +19
Asteroseismology is a powerful tool to infer fundamental stellar properties. The use of these asteroseismic-inferred properties in a growing number of astrophysical contexts makes…
Fundamental properties of five Kepler stars using global asteroseismic quantities and ground-based observations
O. L. Creevey, G. Dogan, A. Frasca +34
We present an asteroseismic study of the solar-like stars KIC 11395018, KIC 10273246, KIC 10920273, KIC 10339342, and KIC 11234888 using short-cadence time series of more than eigh…
Improved calibration of the radii of cool stars based on 3D simulations of convection: implications for the solar model
F. Spada, P. Demarque, S. Basu +1
Main sequence, solar-like stars (M < 1.5 Msun) have outer convective envelopes that are sufficiently thick to affect significantly their overall structure. The radii of these stars…
Testing an Ansatz for the Leading Secular Loop Corrections from Quantum Gravity during Inflation
S. Basu, R. P. Woodard
It is widely believed that the leading secular loop corrections from quantum gravity can be subsumed into a coordinate redefinition. Hence the apparent infrared logarithm correctio…
Spin-orbit alignment of exoplanet systems: ensemble analysis using asteroseismology
T. L. Campante, M. N. Lund, J. S. Kuszlewicz +23
The angle between a planet's orbital axis and the spin axis of its parent star is an important diagnostic of planet formation, migration, and tidal evolution. We seek empirica…
Evidence for the impact of stellar activity on the detectability of solar-like oscillations observed by Kepler
W. J. Chaplin, T. R. Bedding, A. Bonanno +37
We use photometric observations of solar-type stars, made by the NASA Kepler Mission, to conduct a statistical study of the impact of stellar surface activity on the detectability…
Determining distances using asteroseismic methods
V. Silva Aguirre, L. Casagrande, S. Basu +6
Asteroseismology has been extremely successful in determining the properties of stars in different evolutionary stages with a remarkable level of precision. However, to fully explo…
Asteroseismology of old open clusters with Kepler: direct estimate of the integrated RGB mass loss in NGC6791 and NGC6819
A. Miglio, K. Brogaard, D. Stello +21
Mass loss of red giant branch (RGB) stars is still poorly determined, despite its crucial role in the chemical enrichment of galaxies. Thanks to the recent detection of solar-like…
Calibrations of Atmospheric Parameters Obtained from the First Year of SDSS-III APOGEE Observations
Sz. Mészáros, J. Holtzman, A. E. GarcÃa Pérez +25
The SDSS-III Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a three year survey that is collecting 100,000 high-resolution spectra in the near-IR across multipl…
On nonmeasurable subgroups in generalized measurable structures
S. Basu, D. Sen
In this paper, we prove a result on nonmeasurable subgroups in commutative Polish groups with respect to more generalized structures than sigma-finite measures.
Thermal evolution of nanocrystalline co-sputtered Ni-Zr alloy films: Structural, magnetic and MD simulation studies
Debarati Bhattacharya, T. V. Chandrasekhar Rao, K. G. Bhushan +6
Monophasic and homogeneous Ni10Zr7 nanocrystalline alloy films were successfully grown at room temperature by co-sputtering in an indigenously developed three-gun DC/RF magnetron s…
Superconductivity-induced Magnetic Modulation in a Ferromagnet Through an Insulator in LaCaMnO3\SrTiO3\YBa2Cu3O7-δ Hybrid Heterostructures
C. L. Prajapat, Surendra Singh, A. Paul D. Bhattacharya +3
Coexistence of ferromagnetic and superconducting orders and their interplay in ferromagnet-superconductor heterostructures is a topic of intense research. While it is well known th…
Self-regulated gravitational accretion in protostellar discs
E. I. Vorobyov, S. Basu
We present a numerical model for the evolution of a protostellar disc that has formed self-consistently from the collapse of a molecular cloud core. The global evolution of the dis…
Mirror principle and the red-giant bump: the battle of entropy in low-mass stars
S. Hekker, G. C. Angelou, Y. Elsworth +1
The evolution of low-mass stars into red giants is still poorly understood. During this evolution the core of the star contracts and, simultaneously, the envelope expands -- a proc…
Oscillation mode frequencies of 61 main sequence and subgiant stars observed by Kepler
T. Appourchaux, W. J. Chaplin, R. A. Garcia +25
Solar-like oscillations have been observed by Kepler and CoRoT in several solar-type stars, thereby providing a way to probe the stars using asteroseismology. We provide the mode f…
The relation between and for solar-like oscillations
D. Stello, W. J. Chaplin, S. Basu +2
Establishing relations between global stellar parameters and asteroseismic quantities can help improve our understanding of stellar astrophysics and facilitate the interpretation o…
The sensitivity and behaviour of the curvature in the échelle diagram of red-giant stars
S. Hekker, Y. Elsworth, S. Basu +5
In the convective envelopes of relatively cool stars, oscillations are excited by turbulent convection. In these so-called solar-like oscillators, radial oscillation modes appear a…
An asteroseismic membership study of the red giants in three open clusters observed by Kepler: NGC6791, NGC6819, and NGC6811
D. Stello, S. Meibom, R. L. Gilliland +20
Studying star clusters offers significant advances in stellar astrophysics due to the combined power of having many stars with essentially the same distance, age, and initial compo…
Impact of near-degeneracy effects on linear rotational inversions for red-giant stars
F. Ahlborn, J. M. Joel Ong, J. Van Beeck +3
Accurate estimates of internal red-giant rotation rates are a crucial ingredient for constraining and improving current models of stellar rotation. Asteroseismic rotational inversi…
Detection of Solar-Like Oscillations, Observational Constraints, and Stellar Models for Cyg, the Brightest Star Observed by the {\it Kepler} Mission
J. A. Guzik, G. Houdek, W. J. Chaplin +52
Cygni is an F3 spectral-type main-sequence star with visual magnitude V=4.48. This star was the brightest star observed by the original Kepler spacecraft mission. Short-cadenc…
2-D Stellar Evolution Code Including Arbitrary Magnetic Fields. I. Mathematical Techniques and Test Cases
L. H. Li, P. Ventura, S. Basu +2
A high-precision two-dimensional stellar evolution code has been developed for studying solar variability due to structural changes produced by varying internal magnetic fields of…
Buoyancy Effects on the Scaling Characteristics of Atmospheric Boundary Layer Wind Fields in the Mesoscale Range
V. P. Kiliyanpilakkil, S. Basu, A. Ruiz-Columbié +4
We have analyzed long-term wind speed time-series from five field sites up to a height of 300 m from the ground. Structure function-based scaling analysis has revealed that the sca…
Verifying asteroseismically determined parameters of Kepler stars using hipparcos parallaxes: self-consistent stellar properties and distances
V. Silva Aguirre, L. Casagrande, S. Basu +24
Accurately determining the properties of stars is of prime importance for characterizing stellar populations in our Galaxy. The field of asteroseismology has been thought to be par…
2D solar modeling
P. Ventura, V. Penza, L. Li +3
Understanding the reasons of the cyclic variation of the total solar irradiance is one of the most challenging targets of modern astrophysics. These studies prove to be essential a…
Tricritical Phenomena at the Cerium Transition
J. C. Lashley, A. C. Lawson, J. C. Cooley +10
The isostructural transition in the CeLaTh system is measured as a function of La alloying using specific heat, magnetic susceptibility, resistivit…
Asteroseismic inference on rotation, gyrochronology and planetary system dynamics of 16 Cygni
G. R. Davies, W. J. Chaplin, W. M. Farr +13
The solar analogs 16 Cyg A and 16 Cyg B are excellent asteroseismic targets in the \Kepler field of view and together with a red dwarf and a Jovian planet form an interesting syste…
A next-generation LHC heavy-ion experiment
D. Adamová, G. Aglieri Rinella, M. Agnello +395
The present document discusses plans for a compact, next-generation multi-purpose detector at the LHC as a follow-up to the present ALICE experiment. The aim is to build a nearly m…
Measurement of acoustic glitches in solar-type stars from oscillation frequencies observed by Kepler
A. Mazumdar, M. J. P. F. G. Monteiro, J. Ballot +15
For the very best and brightest asteroseismic solar-type targets observed by Kepler, the frequency precision is sufficient to determine the acoustic depths of the surface convectiv…
Asteroseismic inferences on red giants in open clusters NGC 6791, NGC 6819 and NGC 6811 using Kepler
S. Hekker, S. Basu, D. Stello +17
Context: Four open clusters are present in the Kepler field of view and timeseries of nearly a year in length are now available. These timeseries allow us to derive asteroseismic g…
A test of the asteroseismic numax scaling relation for solar-like oscillations in main-sequence and sub-giant stars
H. R. Coelho, W. J. Chaplin, S. Basu +3
Large-scale analyses of stellar samples comprised of cool, solar-like oscillators now commonly utilize the so-called asteroseismic scaling relations to estimate fundamental stellar…
Seismic evidence for a rapidly rotating core in a lower-giant-branch star observed with Kepler
S. Deheuvels, R. A. Garcia, W. J. Chaplin +24
Rotation is expected to have an important influence on the structure and the evolution of stars. However, the mechanisms of angular momentum transport in stars remain theoretically…
Measurement of enhanced electric dipole transition strengths at high spin in Ru: Possible observation of octupole deformation
A. Karmakar, Nazira Nazir, P. Datta +19
The majority of atomic nuclei have deformed shapes and nearly all these shapes are symmetric with respect to reflection. There are only a few reflection asymmetric pear-shaped nucl…
The Burst Mode of Accretion in Primordial Star Formation
A. L. DeSouza, E. I. Vorobyov, S. Basu
We present simulation results for the formation and long-term evolution of a primordial protostellar disk harbored by a first star. Using a 2+1D nonaxisymmetric thin disk numerical…
Na-ion diffusion and electrochemical performance of NaVO anode in Li/Na batteries
Mahesh Chandra, T. S. Khan, Rishabh Shukla +5
We study Na ion diffusion and electrochemical performance of NaVO (NVO) as anode material in Li/Na--ion batteries with the specific capacity of 350 mAhg at the…
Causality Implies Inflationary Back-Reaction
S. Basu, N. C. Tsamis, R. P. Woodard
There is a widespread belief among inflationary cosmologists that a local observer cannot sense super-horizon gravitons. The argument goes that a local observer would subsume super…
Asteroseismology of the solar analogs 16 Cyg A & B from Kepler observations
T. S. Metcalfe, W. J. Chaplin, T. Appourchaux +34
The evolved solar-type stars 16 Cyg A & B have long been studied as solar analogs, yielding a glimpse into the future of our own Sun. The orbital period of the binary system is too…
The James Clerk Maxwell Telescope Legacy Survey of Nearby Star-forming Regions in the Gould Belt
D. Ward-Thompson, J. Di Francesco, J. Hatchell +59
This paper describes a James Clerk Maxwell Telescope (JCMT) legacy survey that has been awarded roughly 500 hrs of observing time to be carried out from 2007 to 2009. In this surve…
Annealing driven positive and negative exchange bias in Fe-Cu-Pt heterostructures at room temperature
M. A. Basha, Harsh Bhatt, Yogesh Kumar +5
We report annealing induced exchange bias in Fe-Cu-Pt based heterostructures with Cu as an intermediate layer (Fe/Cu/Pt heterostructure) and capping layer (Fe/Pt/Cu heterostructure…