Person: Zamorano Calvo, Jaime
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First Name
Jaime
Last Name
Zamorano Calvo
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias FÃsicas
Department
FÃsica de la Tierra y AstrofÃsica
Area
AstronomÃa y AstrofÃsica
Identifiers
143 results
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Now showing 1 - 10 of 143
Item On the nature of the extragalactic number counts in the K-band(Astronomy & Astrophysics, 2009) Barro, G.; Gallego Maestro, Jesús; Pérez González, Pablo Guillermo; Eliche Moral, MarÃa del Carmen; Balcells, M.; Villar, V.; Cardiel López, Nicolás; Cristobal Hornillos, D.; Gil de Paz, Armando; Guzmán, R.; Pello, R.; Prieto, M.; Zamorano Calvo, JaimeContext. The galaxy number counts has been traditionally used to test models of galaxy evolution. However, the origin of significant differences in the shape of number counts at different wavelengths is still unclear. By relating the most remarkable features in the number counts with the underlying galaxy population it is possible to introduce further constraints on galaxy evolution. Aims. We aim to investigate the causes of the different shape of the K-band number counts when compared to other bands, analyzing in detail the presence of a change in the slope around K similar to 17.5. Methods. We present a near-infrared imaging survey, conducted at the 3.5 m telescope of the Calar Alto Spanish-German Astronomical Center (CAHA), covering two separated fields centered on the HFDN and the Groth field, with a total combined area of similar to 0.27 deg(2) to a depth of K similar to 19 (3 sigma, Vega). By combining our data with public deep K-band images in the CDFS (GOODS/ISAAC) and high quality imaging in multiple bands, we extract K-selected catalogs characterized with highly reliable photometric redshift estimates. We derive redshift binned number counts, comparing the results in our three fields to sample the effects of cosmic variance. We derive luminosity functions from the observed K-band in the redshift range [0.25-1.25], that are combined with data from the references in multiple bands and redshifts, to build up the K-band number count distribution. Results. The overall shape of the number counts can be grouped into three regimes: the classic Euclidean slope regime (d log N/dm similar to 0.6) at bright magnitudes; a transition regime at intermediate magnitudes, dominated by M* galaxies at the redshift that maximizes the product phi*dVc/d Omega; and an alpha dominated regime at faint magnitudes, where the slope asymptotically approaches -0.4(alpha + 1) controlled by post-M* galaxies. The slope of the K-band number counts presents an averaged decrement of similar to 50% in the range 15.5 < K < 18.5 (d log N/dm similar to 0.6-0.30). The rate of change in the slope is highly sensitive to cosmic variance effects. The decreasing trend is the consequence of a prominent decrease of the characteristic density phi(K,obs)* (similar to 60% from z = 0.5 to z = 1.5) and an almost flat evolution of M(K,obs)* (1 sigma compatible with M(K,obs)* = -22.89 +/- 0.25 in the same redshift range).Item Deconstructing the K-band number counts(Highlights of Spanich Astrophysics, 2010) Barro, Guillermo; Gallego Maestro, Jesús; Pérez González, Pablo Guillermo; Eliche Moral, MarÃa del Carmen; Balcells, M.; Villar, V.; Cardiel López, Nicolás; Cristobal Hornillos, D.; Gil de Paz, Armando; Guzmán, R.; Pelló, R.; Prieto, M.; Zamorano Calvo, JaimeWe present a study that links the NCs to the rest-frame luminosity functions (LFs) at the passbands probed by the observed K-band at different epochs. Making use of a large K-band selected sample in the Groth Field, HDFN and CDFS (∼0.27deg^(2)), we have derived highly reliable photometric redshift estimates that allow us to estimate LFs in the redshift range [0.25-1.25]. We find that the larger flattening in the slope of the K-band NCs is mostly a consequence of a prominent decrease in the characteristic density (φ∗) around z∼1, and an almost flat evolution of M∗.Item Light Pollution Spanish REECL SQM Network(2015) Zamorano Calvo, Jaime; Sánchez de Miguel, Alejandro; Nievas Rosillo, Mireia; Tapia Ayuga, Carlos; Ocaña González, Francisco; Izquierdo Gómez, Jaime; Gallego Maestro, Jesús; Pascual RamÃrez, SergioThe SQM network of the Spanish Light Pollution Research collaboration (http://guaix.fis.ucm.es/splpr/SQM-REECL) is growing with the help of amateur astronomers and interested citizens. Up to now there are 18 stations. SQM photometers provide measures of the night sky brightness every night using the PySQM software. The analysis of the data provided by the photometers allows the researchers to monitor the nightly, monthly and yearly evolution of the NSB and the relationship with sources of light pollution in intensity and distance. The photometers that are measuring in protected areas will alarm the researchers about eventual increasing of light pollution that could affect the environment. Using models of light dispersion on the atmosphere one can determine which light pollution sources are increasing the sky brightness at different places and in which extension. Networks of fixed photometers acquiring data every night are one of the main inputs to test these models.The collaborative effort of many people (citizen science) pro-vides the necessary data to derive scientific results.Item Photometric catalogue for space and ground night-time remote-sensing calibration: RGB synthetic photometry from Gaia DR3 spectrophotometry(Remote Sensing, 2023) Carrasco, Josep Manel; Cardiel López, Nicolás; Masana, Eduard; Zamorano Calvo, Jaime; Pascual RamÃrez, Sergio; Sánchez De Miguel, Alejandro; González Fuentetaja, Rafael; Izquierdo Gómez, JaimeRecent works have made strong efforts to produce standardised photometry in RGB bands. For this purpose, we carefully defined the transmissivity curves of RGB bands and defined a set of standard sources using the photometric information present in Gaia EDR3. This work aims not only to significantly increase the number and accuracy of RGB standards but also to provide, for the first time, reliable uncertainty estimates using the BP and RP spectrophotometry published in Gaia DR3 instead of their integrated photometry to predict RGB photometry. Furthermore, this method allows including calibrated sources regardless of how they are affected by extinction, which was a major shortcoming of previous work. The RGB photometry is synthesised from the Gaia BP and RP low-resolution spectra by directly using their set of coefficients multiplied with some basis functions provided in the Gaia catalogue for all sources published in Gaia DR3. The output synthetic magnitudes are compared with the previous catalogue of RGB standards available.Item 3C a multi-wavelength database for the future GTC cosmological surveys(First light science with the GTC, 2007) Barro, G.; Gallego Maestro, Jesús; Villar, V.; Zamorano Calvo, JaimeThe 3C Database aims to provide complete multi-wavelength information over different cosmological fields, such as GOODS, Groth or Sa68 allowing detailed studies on wide samples of galaxies.Item Exploring the star forming regions in vigorous star forming galaxies at Z=0.84(Fourth science meeting with the GTC, 2013) Villar, V.; Guzmán, R.; Gallego Maestro, Jesús; Pérez González, Pablo Guillermo; Zamorano Calvo, JaimeWe analyze the properties of star forming regions in a sample of star forming galaxies at z = 0.84. Star forming regions are extracted from B band ACS-HST images. Previously we have substracted a model of the galaxy, fitting a bulged+disk model to the whole galaxy. Special care has been taken masking the star forming regions in the model fitting procedure, yielding more reliable results. We present here the properties of these star forming regions.Item The stellar mass assembly of galaxies from z=0 to z=4: Analysis of a sample selected in the rest-frame near-infrared with Spitzer(Astrophysical journal, 2008) Pérez González, Pablo Guillermo; Rieke, George H.;, George H.; Villar, Victor; Barro, Guillermo; Blaylock, Myra; Egami, Eiichi; Gallego Maestro, Jesús; Gil de Paz, Armando; Pascual, Sergio; Zamorano Calvo, Jaime; Donley, Jennifer L.Using a sample of ~28,000 sources selected at 3.6-4.5 μm with Spitzer observations of the Hubble Deep Field North, the Chandra Deep Field South, and the Lockman Hole (surveyed area ~664 arcmin^2), we study the evolution of the stellar mass content of the universe at 0 < z < 4. We calculate stellar masses and photometric redshifts, based on ~2000 templates built with stellar population and dust emission models fitting the ultraviolet to mid-infrared spectral energy distributions of galaxies with spectroscopic redshifts. We estimate stellar mass functions for different redshift intervals. We find that 50% of the local stellar mass density was assembled at 0 < z < 1 (average star formation rate [SFR] 0.048 M-☉ yr^−1 Mpc^−3), and at least another 40% at 1 < z < 4 (average SFR 0.074 M_☉ yr^−1 Mpc^−3). Our results confirm and quantify the "downsizing" scenario of galaxy formation. The most massive galaxies (M > 10^12.0 M_☉) assembled the bulk of their stellar content rapidly (in 1-2 Gyr) beyond z ~ 3 in very intense star formation events (producing high specific SFRs). Galaxies with 10^11.5 < M < 10^12.0 M_☉ assembled half of their stellar mass before z ~ 1.5, and more than 90% of their mass was already in place at z ~ 0.6. Galaxies with M < 1011.5 M☉ evolved more slowly (presenting smaller specific SFRs), assembling half of their stellar mass below z ~ 1. About 40% of the local stellar mass density of 10^9.0 < M < 10^11.0 M_☉ galaxies was assembled below z ~ 0.4, most probably through accretion of small satellites producing little star formation. The cosmic stellar mass density at z > 2.5 is dominated by optically faint (Rgsim 25) red galaxies (distant red galaxies or BzK sources), which account for ~30% of the global population of galaxies, but contribute at least 60% of the cosmic stellar mass density. Bluer galaxies (e.g., Lyman break galaxies) are more numerous but less massive, contributing less than 50% of the global stellar mass density at high redshift.Item Star formation in the nucleus of the galaxy NGC-5253(Astronomy and astrophysics, 1987) González-Riestra, R.; Rego Fernández, Manuel Eduardo; Zamorano Calvo, JaimeSummary. Optical and ultraviolet spectroscopic observations of the nucleus of the galaxy NGC5253 are analyzed. This galaxy presents the typical features of an elliptical system at large distances from its center. However, its nucleus is dominated by an emission complex composed by severa) giant H rr regions. The analysis of the optical spectra shows that the metallic abundances in the nucleus of the galaxy are below the solar values. The presence of O stars can be deduced from the numerous absorption Iines present in the UV spectrum. The UV emission lines indicate a high effective temperature for the ionizing star cluster. The comparison of the observations with evolutive models of W(Hp) and the slope of the UV continuum shows that the age of the brightest knot of the nucleus of NGC 5253 is less than three millions years. The exact age depends on the choice of the extinction law, not well known in this type of objects. An LMC like law (consistent with the low metallicity of the object) leads to an age of 2.3 106 yr, and to an IMF similar or slightly flatter than that found by Salpeter for the solar neighbourhood, with an upper mass limit in the range 60 M 0 < M0P < 120 M 0 .Item CO^(12) mapping of the low-metallicity blue compact dwarf galaxy Markarian 86(Astrophysical journal, 2002) Gil de Paz, Armando; Silich, S. A.; Madore, B. F.; Sánchez Contreras, C.; Zamorano Calvo, Jaime; Gallego Maestro, JesúsWe have mapped the CO^12 J = 1-0 and J = 2-1 line emission in Markarian 86, one of the most metal-deficient blue compact dwarf galaxies so far detected in CO^12. The CO^12 emission is distributed in a horseshoe-like structure that follows the locus of the most recent star formation regions. The minimum in molecular line emission corresponds to the position of an older, massive nuclear starburst. The H_2 mass of the galaxy [in the range of (0.4-5) x 10^7 M_⨀] and its morphology have been compared with the predictions of hydrodynamic simulations of the evolution of the interstellar medium surrounding a nuclear starburst. These simulations suggest that the physical conditions in the gas swept out by the starburst could have led to the formation of the ring of molecular gas reported here. This result provides an attractive scenario for explaining the propagation (in a galactic scale) of the star formation in dwarf galaxies.Item PySQM the UCM open source software to read, plot and store data from SQM photometers(2014) Nievas Rosillo, Mireia; Zamorano Calvo, JaimeA multi platform software (PySQM) has been designed to read, store and plot data from Unihedron SQM-LE and SQM-LU photometers. It is intended to record night sky brightness data obtained with fixed SQM photometers. PySQM is distributed as open source software.