81 results match your criteria: "Institute of Astronomy and Astrophysics[Affiliation]"

IRAS 04368+2557 is a solar-type (low-mass) protostar embedded in a protostellar core (L1527) in the Taurus molecular cloud, which is only 140 parsecs away from Earth, making it the closest large star-forming region. The protostellar envelope has a flattened shape with a diameter of a thousand astronomical units (1 AU is the distance from Earth to the Sun), and is infalling and rotating. It also has a protostellar disk with a radius of 90 AU (ref.

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Recent advances in -FeSe and related superconductors.

Sci Technol Adv Mater

February 2013

Institute of Physics, Academia Sinica, Taipei, Taiwan.

Article Synopsis
  • - Over the past four years, significant progress has been made in understanding -FeSe superconductors, with high-quality single crystals being prepared for detailed studies.
  • - Characterization of these crystals has revealed that superconductivity in -FeSe is linked to structural changes at low temperatures, which are associated with various anomalies.
  • - Recent findings indicate that an energy gap opens around 130-140 K due to changes in the electronic structure before the lattice distortion occurs, suggesting that short-range orbital or charge orders influence superconductivity.
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Superconductivity was recently found in the tetragonal phase FeSe. A structural transformation from tetragonal to orthorhombic (or monoclinic, depending on point of view) was observed at low temperature, but was not accompanied by a magnetic ordering as commonly occurs in the parent compounds of FeAs-based superconductors. Here, we report the correlation between structural distortion and superconductivity in FeSe(1-x) thin films with different preferred growth orientations.

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We present the full set of power spectra of cosmic microwave background (CMB) temperature and polarization anisotropies due to the coupling between quintessence and pseudoscalar of electromagnetism. This coupling induces a rotation of the polarization plane of the CMB, thus resulting in a nonvanishing B mode and parity-violating TB and EB modes. Using the BOOMERANG data from the flight of 2003, we derive the most stringent constraint on the coupling strength.

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An inverse compton process for the excess diffuse EUV emission from the virgo and coma galaxy clusters.

Science

December 1997

Institute of Astronomy and Astrophysics, Academia Sinica, Post Office Box 1-87, Nankang, Taipei, Taiwan 115, Republic of China.

The excess extreme-ultraviolet (EUV) emission detected in the Virgo and Coma clusters is explained by inverse Compton scattering of cosmic microwave background photons, which are scattered by the relativistic electrons that account for the extended radio synchrotron emission of these clusters. The lower limits of the average magnetic fields of these clusters estimated from the EUV excess are close to the equipartition magnetic fields derived from radio observations, indicating that the electron energies and magnetic field energies might be close to equipartition. The excess emission suggests energy reservoirs of approximately 10(61) and approximately 10(60) ergs for the Coma and Virgo clusters, respectively.

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