The X17.0 solar flare of September 07, 2005 released high-energy neutrons, that were detected by the Solar Neutron Telescope (SNT) at Sierra Negra, Mexico. In two separate and independent studies of this solar neutron event, the energy spectra as a power law was calculated ( Sako, T., et al., 2006, ApJ, 651, 69. Watanabe, K., et al., 2006. ApJ, 636

We present intermediate- and low-resolution optical spectroscopy (650-915 nm) of seven faint, very red objects ( 20>I>=17.8 , I-Z>= 0.5) discovered in a CCD-based IZ survey covering an area of 1 deg2 in the central region of the Pleiades open cluster. The observed spectra show that these objects are very cool dwarfs having spectral types in the

We report here the discovery of very low amplitude oscillations in the Pleiades star HD 23628. The 14-nights high quality light curve designates HD 23628 as a new member of the δ Scuti stars class. Amplitude spectra indicate a multi-periodic pulsation behaviour, and four pulsation frequencies have been detected so far. The frequency distribution

Observational evidence accumulated over the last decade strongly supports the idea that the ionizing radiation field in active galactic nuclei (AGNs) is anisotropic. Here we report on new evidence for this anisotropy in the particular case of the Seyfert 2 galaxy NGC 5252. H I observations of this galaxy reveal neutral gas surrounding the nucleus

High-resolution spectroscopy (R>25,000) is a robust and powerful tool in the near-infrared characterization of exoplanet atmospheres. It has unambiguously revealed the presence of carbon monoxide and water in several hot Jupiters, measured the rotation rate of beta Pic b, and suggested the presence of fast day-to-night winds in one atmosphere. The

The HST/ACS Survey of Galactic Globular Clusters includes F606W and F814W observations of 66 clusters (Sarajedini et al. 2007). We present new global mass functions (MFs) for a significant sub-sample of clusters in the survey. We also present updated core radii, tidal radii, and concentrations for many of these clusters. This new information allows