Related papers: Using eigenmode-mixing to measure or constrain the…
The principal aim of observational helioseismology is to determine mode parameters of the solar oscillations as accurately as possible. Yet estimates of the mode parameters are subject to many sources of noise, including inevitable gaps in…
Observations of the Cosmic Microwave Background (CMB) B-mode polarisation provide a unique probe of inflationary physics. Extracting a reliable constraint on the tensor-to-scalar ratio $r$ nonetheless demands stringent suppression of…
The cosmic microwave background polarization is rich of cosmological information complementary to those from temperature anisotropies. Linear polarization can be decomposed uniquely in two components of opposite parities, called E and B.…
Observations of quiet Sun from the Solar Optical Telescope/Spectro-Polarimeter (SOT/SP) aboard the Hinode spacecraft would reveal the magnetic characters of the solar photosphere. By making use of the deep mode observations of three quiet…
A poor understanding of the impact of convective turbulence in the outer layers of the Sun and Sun-like stars challenges the advance towards an improved understanding of their internal structure and dynamics. Assessing and calibrating these…
p-mode oscillations in solar-like stars are excited by the outer convection zone in these stars and reflected close to the surface. The p-modes are trapped inside an acoustic cavity, but the modes only stay trapped up to a given frequency…
The importance of the magnetic (B) field in the formation of infrared dark clouds (IRDCs) and massive stars is an ongoing topic of investigation. We studied the plane-of-sky B field for one IRDC, G028.23-00.19, to understand the interaction…
Helioseismology has revolutionized our understanding of the Sun by analyzing its global oscillation modes. However, the solar core remains elusive, limiting a full understanding of its evolution. In this work, we study a previously…
We use the three-dimensional hydrodynamic code of Stein and Nordlund to realistically simulate the upper layers of the solar convection zone in order to study physical characteristics of solar oscillations. Our first result is that the…
We examine the potential of polarization bispectra of the cosmic microwave background (CMB) to constrain primordial magnetic fields (PMFs). We compute all possible bispectra between temperature and polarization anisotropies sourced by PMFs…
In the oscillation spectra of giant stars, nonradial modes may be seen to undergo avoided crossings, which produce a characteristic "mode bumping" of the otherwise uniform asymptotic p- and g-mode patterns in their respective echelle…
Normal-mode coupling is a technique applied to probe the solar interior using surface observations of oscillations. The technique, which is straightforward to implement, makes more use of the seismic information in the wavefield than other…
We present new results on the structure of the solar core, obtained with new sets of frequencies of solar low-degree p modes obtained from the BiSON network. We find that different methods used in extracting the different sets of…
We demonstrate a new way of studying interplanetary magnetic field -- Ground State Alignment (GSA). Instead of sending thousands of space probes, GSA allows magnetic mapping with any ground telescope facilities equipped with…
Sunspots are prominent manifestations of solar magnetoconvection and imaging their subsurface structure is an outstanding problem of wide physical importance. Travel times of seismic waves that propagate through these structures are…
Here we present a detailed analysis of solar acoustic mode frequencies and their rotational splittings for modes with degree up to 900. They were obtained by applying spherical harmonic decomposition to full-disk solar images observed by…
When the polarimetric sensitivity and the angular resolution exceed a threshold, magnetic fields show up almost everywhere on the solar surface. Here I revise the observational properties of the weakest polarization signals, which appear in…
Small cyclic variations in the frequencies of acoustic modes are expected to be a common phenomenon in solar-like pulsators, as a result of stellar magnetic activity cycles. The frequency variations observed throughout the solar and stellar…
The measurement of B-mode polarization of the cosmic microwave background at large angular scales by the BICEP experiment suggests a stochastic gravitational wave background from early-universe inflation with a surprisingly large amplitude.…
We make predictions of the detectability of low-frequency p modes. Estimates of the powers and damping times of these low-frequency modes are found by extrapolating the observed powers and widths of higher-frequency modes with large…