Spectroscopic Observations of Planetary Nebulae in the Northern Spur of M31

We present spectroscopy of three planetary nebulae (PNe) in the Northern Spur of the Andromeda Galaxy (M31) obtained with the Double Spectrograph on the 5.1 m Hale Telescope at the Palomar Observatory. The samples are selected from the observations of Merrett et al. Our purpose is to investigate formation of the substructures of M31 using PNe as a tracer of chemical abundances. The [O III] 4363 auroral line is detected in the spectra of two objects, enabling temperature determinations. Ionic abundances are derived from the observed collisionally excited lines, and elemental abundances of nitrogen, oxygen, and neon as well as sulphur and argon are estimated. Correlations between oxygen and the alpha-element abundance ratios are studied, using our sample and the M31 disk and bulge PNe from the literature. In one of the three PNe, we observed relatively higher oxygen abundance compared to the disk sample in M31 at similar galactocentric distances. The results of at least one of the three Northern Spur PNe might be in line with the proposed possible origin of the Northern Spur substructure of M31, i.e. the Northern Spur is connected to the Southern Stream and both substructures comprise the tidal debris of the satellite galaxies of M31.Comment: 5 tables, 17 figures; accepted for publication in Ap

Breve reseña de las aguas sulfurado-sódicas termales de Montemayor o Baños...

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

León

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

Estudio de la estabilidad y dispersión del problema de propagación de ondas sísmicas en 2-D utilizando el método de diferencias finitas generalizadas

AbstractThis paper shows the solution to the problem of seismic wave propagation in 2-D using generalized finite difference (GFD) explicit schemes. Regular and irregular meshes can be used with this method.As we are using an explicit method, it is necessary to obtain the stability condition by using the von Neumann analysis. We also obtained the star dispersion formulas for the phase velocities for the P and S waves, as well as the ones for the group velocities.As the control over the irregularity in the mesh is very important in the application of this method, we have defined an index of irregularity for the star (IIS) and another for the cloud (IIC), analyzing its relationship with the dispersion and time step used in the calculations

Atlas de agricultura y sus industrias anejas

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 201

Instrucción y fórmula para los Alcaldes pedáneos, regidores y escribanos fieles de fechos, y otors a quienes corresponda de los lugares de los quatro sexmos en que se divide el Señorío de Molina, los de la Tierra de Almazan, los del Ducado de Medinaceli...

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2013Sign.: []2, B-Q2, R1H. escrtas por ambas cara

Melitón Sauro : leyenda fantástica

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2012-201

Discurso que con motivo de colocar ... el retrato de D. Fernando VII en el nuevo local que para el estudio de medicina clínica ha destinado la ... Junta de Gobierno del Real Hospital General de esta ciudad

En el título consta el año 182