arXiv subjects

Carlos M. Gutierrez

Publications and source records attributed to Carlos M. Gutierrez.

21 records · Page 2Linked to original sources

arXiv2000

Cross-correlation of Tenerife data with Galactic templates - evidence for spinning dust?

The recent discovery of dust-correlated diffuse microwave emission has prompted two rival explanations: free-free emission and spinning dust grains. We present new detections of this component at 10 and 15 GHz by the switched-beam Tenerife experiment. The data show a turnover in the spectrum and thereby supports the spinning dust hypothesis. We also present a significant detection of synchrotron radiation at 10 GHz, useful for normalizing foreground contamination of CMB experiments at high-galactic latitudes.

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arXiv1999

The Tenerife Cosmic Microwave Background Maps: Observations and First Analysis

The results of the Tenerife Cosmic Microwave Background (CMB) experiments are presented. These observations cover 5000 and 6500 square degrees on the sky at 10 and 15 GHz respectively centred around Dec.~ +35 degrees. The experiments are sensitive to multipoles l=10-30 which corresponds to the Sachs-Wolfe plateau of the CMB power spectra. The sensitivity of the results are ~31 and \~12 microK at 10 and 15 GHz respectively in a beam-size region (5 degrees FWHM). The data at 15 GHz show clear detection of structure at high Galactic latitude; the results at 10 GHz are compatible with these, but at lower significance. A likelihood analysis of the 10 and 15 GHz data at high Galactic latitude, assuming a flat CMB band power spectra gives a signal Delta T_l=30+10-8 microK (68 % C.L.). Including the possible contaminating effect due to the diffuse Galactic component, the CMB signal is Delta T_l=30+15-11 microK. These values are highly stable against the Galactic cut chosen. Assuming a Harrison-Zeldovich spectrum for the primordial fluctuations, the above values imply an expected quadrupole Q_RMS-PS=20+10-7 microK which confirms previous results from these experiments, and which are compatible with the COBE DMR.

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arXiv1997

The stellar and gaseous kinematics in NGC 253

This paper presents observations with intermediate spectral and spatial resolution along the major and minor axes of the starburst galaxy NGC 253. The spectral ranges analyzed are in the region of the stellar MgIb (5175 A), the near IR CaII triplet (8550 A) absorption features, and the region of the Halpha emission line. We have compared the shape of the stellar features with those of reference stars and determined the line-of-sight velocity distribution (LOSVD) of the stellar component by using a two-dimensional Gaussian decomposition algorithm, and show for the first time the rotation curve of the stellar component in NGC 253. Comparing the recesion velocity curves of the gas and stars, it is seen that the stellar component has a decoupled kinematics respect to the gas, displaying a shollower velocity gradient and larger velocity dispersion that the gas in the inner regions. The minor axis kinematics together with the kinematics across the central 40$''$ along the major axis, suggest the presence of a rotating body with a kinematically misaligned axis respect to the main disk of the galaxy. The asymmetries in the LOSVD along the minor axis together with the steep velocity gradient of the gaseous component suggest a merger scenario to explain the these kinematically signatures. The enclosed mass in the central regions is computed to be (2.4+-0.5) 10^7$ Mo for a radius of r=0.7'' (10 pc). A double gaseous component in the central 6 arcsecs is detected from the [SIII] lambda 9069 A data along the minor axis; this seems to be the signature of a superbubble due to a supernova rate of 0.05 yr^{-1}.

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