Search Publications
Coronal equatorial rotation during solar cycle 23: radial variation and connections with helioseismology
Giordano, S.; Mancuso, S.
Time-series observations of the O vi 1032 Å spectral line intensity provided by the UltraViolet Coronagraph Spectrometer (UVCS) telescope aboard the Solar and Heliospheric Observatory (SOHO) spacecraft have been analyzed to establish the rotational characteristics of the equatorial solar corona as a function of height and time during solar cycle 2…
Period-luminosity relations for Small Magellanic Cloud Cepheid based on AKARI archival data
Ngeow, Chow-Choong; Kanbur, Shashi M.; Citro, Danielle M.
In this work we matched the AKARI archival data to the Optical Gravitational Lensing Experiment III (OGLE-III) catalogue to derive the mid-infrared period-luminosity (PL) relations for Small Magellanic Cloud (SMC) Cepheids. Mismatched AKARI sources were eliminated using random-phase colours obtained from the full I-band light curves from OGLE-III.…
A Spitzer-MIPS Search for Dust in Compact High-velocity H I Clouds
Elvis, Martin; Williams, Rik J.; Nicastro, Fabrizio +2 more
We employ three-band Spitzer-MIPS observations to search for cold dust emission in three neutral hydrogen compact high-velocity clouds (CHVCs) in the vicinity of the Milky Way. Far-infrared emission correlated with H I column density was previously reported in HVC Complex C, indicating that this object contains dust heated by the Galactic radiatio…
HSTOF ENA observations and energetic ion distributions in the heliosheath
Hsieh, K. C.; Hilchenbach, M.; Czechowski, A.
Context. Launched in 1996, HSTOF on board SOHO was the first instrument to detect the energetic neutral atoms (ENA) from the heliosheath. After mid 2003, the field of view of HSTOF was restricted to the flank sectors of the heliosheath, in which region the energetic ion distributions are still unknown. Interpretation of these data requires underst…
Scales of the magnetic fields in the quiet Sun
Sainz Dalda, A.; López Ariste, A.
Context. The presence of a turbulent magnetic field in the quiet Sun has been unveiled observationally using different techniques. The magnetic field is quasi-isotropic and has field strengths weaker than 100 G. It is pervasive and may host a local dynamo.
Aims: We aim to determine the length scale of the turbulent magnetic field in the quiet…
Distance and Reddening of the Isolated Dwarf Irregular Galaxy NGC 1156
Kim, Minjin; Lee, Joon Hyeop; Kyeong, Jaemann +3 more
We present a photometric estimation of the distance and reddening values to the dwarf irregular galaxy NGC 1156, that is one of the best targets for the study of isolated dwarf galaxies in the nearby universe. We used imaging data sets of the Hubble Space Telescope (HST) Advanced Camera for Surveys, High Resolution Channel of the central region of…
CSS091109:035759+102943: A candidate polar
Schwope, A. D.; Thinius, B.
We report optical time-resolved photometry of the CRTS transient CSS091109:035759+102943. Pronounced orbital variability with a 114 min period, large X-ray variability and the IR to X-ray spectral energy distribution suggest a classification as a magnetic cataclysmic binary, a likely AM Herculis star or polar.
High-resolution optical imaging of the core of the globular cluster M15 with FastCam
Rodríguez, Luis F.; Rebolo, Rafael; Díaz-Sánchez, Anastasio +6 more
We present high-resolution I -band imaging of the core of the globular cluster M15 obtained at the 2.5-m Nordic Optical Telescope with FastCam, a low readout noise L3CCD-based instrument. Short exposure times (30 ms) were used to record 200 000 images (512 × 512 pixels each) over a period of 2 h and 43 min. The lucky imaging technique was then app…
The Rosetta campaign to detect an exosphere at Lutetia
Stern, S. A.; Altwegg, K.; A'Hearn, M. F. +15 more
On 10th July 2010 the Rosetta spacecraft passed within 3160 km of asteroid 21 Lutetia during which seven instruments attempted to detect an exosphere. A comparison of the sensitivity is made between the different instruments based on a simple spherical out-gassing point source model, which was used to infer that the Lutetia exosphere production ra…
Experimental evaluation of common spacecraft data analysis techniques for reconnection region analysis in a laboratory plasma
Yoo, Jongsoo; Yamada, Masaaki
A laboratory plasma is utilized to assess the effectiveness of several prominent spacecraft data analysis techniques. These include minimum variance analysis on the magnetic field (MVAB) and various boundary-crossing time analyses (BCTA) such as the constant velocity approach (CVA), constant thickness approach (CTA), and minimum thickness variance…