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We present observations with the new 11 GHz radiometer of the COSMOSOMAS experiment at the Teide Observatory (Tenerife). The sky region between 0 deg <= RA <= 360 deg and 26 deg <= DEC 49 deg (ca. 6500 square degrees) was observed with an angular resolution of 0.9 deg. Two orthogonal independent channels in the receiving system measured total power signals from linear polarizations with a 2 GHz bandwidth. Maps with an average sensitivity of 50 microK per beam have been obtained for each channel. At high Galactic latitude (|b|>30deg) the 11 GHz data are found to contain the expected cosmic microwave background as well as extragalactic radiosources, galactic synchrotron and free-free emission, and a dust-correlated component which is very likely of galactic origin. At the angular scales allowed by the window function of the experiment, the dust-correlated component presents an amplitude Delta T aprox. 9-13 microK while the CMB signal is of order 27 microK. The spectral behaviour of the dust-correlated signal is examined in the light of previous COSMOSOMAS data at 13-17 GHz and WMAP data at 22-94 GHz in the same sky region. We detect a flattening in the spectral index of this signal below 20 GHz which rules out synchrotron radiation as being responsible for the emission. This anomalous dust emission can be described by a combination of free-free emission and spinning dust models with a flux density peaking around 20 GHz.
The CMB polarization promises to unveil the dawn of time measuring the gravitational wave background emitted by the Inflation. The CMB signal is faint, however, and easily contaminated by the Galactic foreground emission, accurate measurements of whi
We estimate the dust polarized emission in our galaxy at high galactic latitudes, which is the dominant foreground for measuring CMB polarization using the high frequency instrument (HFI) aboard Planck surveyor. We compare it with the level of CMB po
We present a sample of 17 newly discovered ultracool dwarf candidates later than ~M8, drawn from 231.90 arcmin2 of {it Hubble Space Telescope} Wide Field Camera 3 infrared imaging. By comparing the observed number counts for 17.5<J_125<25.5 AB mag to
Polarization is an important indicator of stellar evolution, especially for stars evolving from red-giant stage to planetary nebulae. However, not much is known about the polarimetric properties of the carbon-enhanced metal-poor (CEMP) stars, althoug
In this chapter we review the young stars and molecular clouds found at high Galactic latitudes $(|b| ge 30^circ)$. These are mostly associated with two large-scale structures on the sky, the Gould Belt and the Taurus star formation region, and a han