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Binary pulsars studies with multiwavelength sky surveys - I. Companion star identification

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
Binary pulsars studies with multiwavelength sky surveys - I. Companion star identification
Autores: 
Mignani, RP; Corongiu, A; Pallanca, C; Oates, SR; Yershov, VN; Breeveld, AA; Page, MJ; Ferraro, FR; Possenti, A; Jackson, AC
Resumen: 
The identification of the stellar companions to binary pulsars is key to studying the evolution of the binary system and how this is influenced by the interactions between the two stars. For only a fraction of the known binary pulsars, the stellar companions have been identified. Here, we used 11 source catalogues available from multiwavelength (ultraviolet, optical, infrared) imaging sky surveys to search for the stellar companions of a sample of 144 field binary pulsars (i.e. not in globular clusters) selected from the Australia Telescope National Facility data base (version 1.48) and from the public list of gamma-ray pulsars detected by Fermi. We found positional associations in at least one source catalogue for 22 pulsars, of which 10 are detected in gamma-rays by Fermi, including 15 millisecond pulsars. For six pulsars in our compilation, we confirm their identifications. For another seven pulsars that had yet not been identified, we examine potential identifications. In particular, we identified a likely companion star candidate to PSR J2317+1439, whereas for both PSR B1953+29 and PSR J1935+1726 the companion star identification is more uncertain. Follow-up observations of these three pulsars are needed to settle the proposed identifications. For the remaining nine pulsars that had been already identified, we provide additional spectral information in at least one of the surveys' spectral bands, which we will use to better constrain the stars' spectral energy distributions.
Autor principal: 
Mignani, RP
Autor/es del IAA: 
Oates, S. R.
DOI: 
10.1093/mnras/stu1300
Revista: 
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Fecha de publicación: 
2014/09/21
Volumen: 
443
Issue: 
3
Páginas: 
2223-2241
Tipo de documento: 
Article
Palabras clave: 
catalogues; surveys; stars: pulsars: general

Structuring research methods and data with the research object model: genomics workflows as a case study

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
Structuring research methods and data with the research object model: genomics workflows as a case study
Autores: 
Hettne, KM; Dharuri, H; Zhao, J; Wolstencroft, K; Belhajjame, K; Soiland-Reyes, S; Mina, E; Thompson, M; Cruickshank, D; Verdes-Montenegro, L; Garrido, J; de Roure, D; Corcho, O; Klyne, G; van Schouwen, R; 't Hoen, PAC; Bechhofer, S; Goble, C; Roos, M
Resumen: 
Background: One of the main challenges for biomedical research lies in the computer-assisted integrative study of large and increasingly complex combinations of data in order to understand molecular mechanisms. The preservation of the materials and methods of such computational experiments with clear annotations is essential for understanding an experiment, and this is increasingly recognized in the bioinformatics community. Our assumption is that offering means of digital, structured aggregation and annotation of the objects of an experiment will provide necessary meta-data for a scientist to understand and recreate the results of an experiment. To support this we explored a model for the semantic description of a workflow-centric Research Object (RO), where an RO is defined as a resource that aggregates other resources, e. g., datasets, software, spreadsheets, text, etc. We applied this model to a case study where we analysed human metabolite variation by workflows. Results: We present the application of the workflow-centric RO model for our bioinformatics case study. Three workflows were produced following recently defined Best Practices for workflow design. By modelling the experiment as an RO, we were able to automatically query the experiment and answer questions such as 'which particular data was input to a particular workflow to test a particular hypothesis?', and 'which particular conclusions were drawn from a particular workflow?'. Conclusions: Applying a workflow-centric RO model to aggregate and annotate the resources used in a bioinformatics experiment, allowed us to retrieve the conclusions of the experiment in the context of the driving hypothesis, the executed workflows and their input data. The RO model is an extendable reference model that can be used by other systems as well. Availability: The Research Object is available at http://www.myexperiment.org/packs/428 The Wf4Ever Research Object Model is available at http://wf4ever.github.io/ro
Autor principal: 
Hettne, KM
Autor/es del IAA: 
Verdes-Montenegro, Lourdes; Garrido, Julian
DOI: 
10.1186/2041-1480-5-41
Revista: 
JOURNAL OF BIOMEDICAL SEMANTICS
Fecha de publicación: 
2014/09/18
Volumen: 
5
Tipo de documento: 
Article
Palabras clave: 
Semantic web models; Scientific workflows; Digital libraries; Genome wide association study
Número de artículo: 
41

MAGIC gamma-ray and multi-frequency observations of flat spectrum radio quasar PKS 1510-089 in early 2012

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
MAGIC gamma-ray and multi-frequency observations of flat spectrum radio quasar PKS 1510-089 in early 2012
Autores: 
Aleksic, J; Ansoldi, S; Antonelli, LA; Antoranz, P; Babic, A; Bangale, P; de Almeida, UB; Barrio, JA; Gonzalez, JB; Bednarek, W; Bernardini, E; Biland, A; Blanch, O; Bonnefoy, S; Bonnoli, G; Borracci, F; Bratz, T; Carmona, E; Carosi, A; Fidalgo, DC; Colin, P; Colombo, E; Contreras, JL; Cortina, I; Covino, S; Da Vela, P; Dazzi, F; De Angelis, A; De Caneva, G; De Lotto, B; Mendez, CD; Doert, M; Dominguez, A; Presters, DD; Dorner, D; Doro, M; Einecke, S; Eisenacher, D; Elsaesser, D; Farina, E; Ferenc, D; Fonseca, MV; Font, L; Frantzen, K; Fruck, C; Lopez, RJG; Garczarczyk, M; Terrats, DG; Gaug, M; Godinovic, N; Munoz, AG; Gozzini, SR; Hadasch, D; Hayashida, M; Herrera, J; Herrero, A; Hildebrand, D; Hose, J; Hrupec, D; Idec, W; Kadenius, V; Kellermann, H; Kodani, K; Konno, Y; Krause, J; Kubo, H; Kushida, J; La Barbera, A; Lelas, D; Lewandowska, N; Lindfors, E; Lombardi, S; Lopez, M; Lopez-Coto, R; Lopez-Oramas, A; Lorenz, E; Lozano, I; Makariev, M; Mallotw, K; Maneva, G; Mankuzhiyil, N; Mannheim, K; Maraschi, L; Marcote, B; Mariotti, M; Martinez, M; Mazin, D; Menzel, U; Meucci, M; Miranda, JM; Mirzoyan, R; Moralejo, A; Munar-Adrover, P; Nakajima, D; Niedzwiecki, A; Nilsson, K; Nishijima, K; Noda, K; Nowak, N; Orito, R; Overkemping, A; Paiano, S; Palatiello, M; Paneque, D; Paoletti, R; Paredes, JM; Paredes-Fortuny, X; Partini, S; Persic, M; Prada, F; Moroni, PGP; Prandini, E; Preziuso, S; Puljak, I; Reinthal, R; Rhode, W; Ribo, M; Rico, J; Garcia, JR; Rugamer, S; Saggion, A; Saito, T; Saito, K; Satalecka, K; Scalzotto, V; Scapin, V; Schultz, C; Schweizer, T; Shore, SN; Sillanpaa, A; Sitarek, J; Snidaric, I; Sobczynska, D; Spanier, F; Stamatescu, V; Stamerra, A; Steinbring, T; Storz, J; Strzys, M; Sun, S; Suric, T; Takalo, L; Takami, H; Tavecchio, F; Temnikov, P; Terzic, T; Tescaro, D; Teshima, M; Thaele, J; Tibolla, O; Torres, DF; Toyama, T; Treves, A; Uellenbeck, M; Vogler, P; Wagner, RM; Zandanel, F; Zanin, R; Lucarelli, F; Pittori, C; Vercellone, S; Verrecchia, F; Buson, S; D'Ammando, F; Stawarz, L; Giroletti, M; Orienti, M; Mundell, C; Steele, I; Zarpudin, B; Raiteri, CM; Villata, M; Sandrinelli, A; Lahteenmaki, A; Tammi, J; Tornikoski, M; Hovatta, T; Readhead, ACS; Max-Moerbeck, W; Richards, JL; Jorstad, S; Marscher, A; Gurwell, MA; Larionov, VM; Blinov, DA; Konstantinova, TS; Kopatskaya, EN; Larionova, LV; Earionova, EG; Morozova, DA; Troitky, IS; Mokrushina, AA; Pavlova, YV; Chen, WP; Lin, HC; Panwar, N; Agudo, I; Casadio, C; Gomez, JL; Molina, SN; Kurtanidze, OM; Nikolashvili, MG; Kurtanidze, SO; Chigladze, RA; Acosta-Pulido, JA; Carnerero, MI; Manilla-Robles, A; Ovcharov, E; Bozhilov, V; Metodieva, I; Aller, MF; Aller, HD; Fuhrman, L; Angelakis, E; Nestoras, I; Krichbaue, TP; Zensue, JA; Ungerechts, H; Sievers, A
Resumen: 
Aims. Amongst more than fifty blazars detected in very high energy (VHE, E > 100 GeV) gamma rays, only three belong to the subclass of flat spectrum radio quasars (FSRQs). The detection of FSRQs in the VHE range is challenging, mainly because of their soft spectra in the GeV-TeV regime. MAGIC observed PKS 1510-089 (z = 0.36) starting 2012 February 3 until April 3 during a high activity state in the high energy (HE, E > 100 MeV) gamma-ray band observed by AGILE and Fermi. MAGIC observations result in the detection of a source with significance of 6.0 standard deviations (sigma). We study the multi-frequency behaviour of the source at the epoch of MAGIC observation, collecting quasi-simultaneous data at radio and optical (GASP-WEBT and F-Gamma collaborations, REM, Steward, Perkins, Liverpool, OVRO, and VLBA telescopes), X-ray (Swift satellite), and HE gamma-ray frequencies. Methods. We study the VHE gamma-ray emission, together with the multi-frequency light curves, 43 GHz radio maps, and spectral energy distribution (SED) of the source. The quasi-simultaneous multi-frequency SED from the millimetre radio band to VHE gamma rays is modelled with a one-zone inverse Compton model. We study two different origins of the seed photons for the inverse Compton scattering, namely the infrared torus and a slow sheath surrounding the jet around the Very Long Baseline Array (VLBA) core. Results. We find that the VHE gamma-ray emission detected from PKS 1510-089 in 2012 February-April agrees with the previous VHE observations of the source from 2009 March-April. We find no statistically significant variability during the MAGIC observations on daily, weekly, or monthly time scales, while the other two known VHE FSRQs (3C 279 and PKS 1222+216) have shown daily scale to sub-hour variability. The gamma-ray SED combining AGILE, Fermi and MAGIC data joins smoothly and shows no hint of a break. The multi-frequency light curves suggest a common origin for the millimetre radio and HE gamma-ray emission, and the HE gamma-ray flaring starts when the new component is ejected from the 43GHz VLBA core and the studied SED models fit the data well. However, the fast HE gamma-ray variability requires that within the modelled large emitting region, more compact regions must exist. We suggest that these observed signatures would be most naturally explained by a turbulent plasma flowing at a relativistic speed down the jet and crossing a standing conical shock.
Autor principal: 
Aleksic, J
Autor/es del IAA: 
Dominguez, A.; Prada, F.; Zandanel, F.
DOI: 
10.1051/0004-6361/201423484
Revista: 
ASTRONOMY & ASTROPHYSICS
Fecha de publicación: 
2014/09
Volumen: 
569
Tipo de documento: 
Article
Palabras clave: 
galaxies: active; galaxies: jets; gamma rays: galaxies; quasars: individual: PKS 1510-089
Número de artículo: 
A46

The Gaia-ESO Survey: Stellar content and elemental abundances in the massive cluster NGC 6705

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
The Gaia-ESO Survey: Stellar content and elemental abundances in the massive cluster NGC 6705
Autores: 
Cantat-Gaudin, T; Vallenari, A; Zaggia, S; Bragaglia, A; Sordo, R; Drew, JE; Eisloeffel, J; Farnhill, HJ; Gonzalez-Solares, E; Greimel, R; Irwin, MJ; Kupcu-Yoldas, A; Jordi, C; Blomme, R; Sampedro, L; Costado, MT; Alfaro, E; Smiljanic, R; Magrini, L; Donati, P; Friel, ED; Jacobson, H; Abbas, U; Hatzidimitriou, D; Spagna, A; Vecchiato, A; Balaguer-Nunez, L; Lardo, C; Tosi, M; Pancino, E; Klutsch, A; Tautvaisiene, G; Drazdauskas, A; Puzeras, E; Jimenez-Esteban, F; Maiorca, E; Geisler, D; Roman, IS; Villanova, S; Gilmore, G; Randich, S; Bensby, T; Flaccomio, E; Lanzafame, A; Recio-Blanco, A; Damiani, F; Hourihane, A; Jofre, P; de Laverny, P; Masseron, T; Morbidelli, L; Prisinzano, L; Sacco, GG; Sbordone, L; Worley, CC
Resumen: 
Context. Chemically inhomogeneous populations are observed in most globular clusters, but not in open clusters. Cluster mass seems to play a key role in the existence of multiple populations. Aims. Studying the chemical homogeneity of the most massive open clusters is needed to better understand the mechanism of their formation and determine the mass limit under which clusters cannot host multiple populations. Here we studied NGC 6705, which is a young and massive open cluster located towards the inner region of the Milky Way. This cluster is located inside the solar circle. This makes it an important tracer of the inner disk abundance gradient. Methods. This study makes use of BVI and ri photometry and comparisons with theoretical isochrones to derive the age of NGC 6705. We study the density profile of the cluster and the mass function to infer the cluster mass. Based on abundances of the chemical elements distributed in the first internal data release of the Gaia-ESO Survey, we study elemental ratios and the chemical homogeneity of the red clump stars. Radial velocities enable us to study the rotation and internal kinematics of the cluster. Results. The estimated ages range from 250 to 316 Myr, depending on the adopted stellar model. Luminosity profiles and mass functions show strong signs of mass segregation. We derive the mass of the cluster from its luminosity function and from the kinematics, finding values between 3700 M-circle dot and 11 000 M-circle dot. After selecting the cluster members from their radial velocities, we obtain a metallicity of [Fe/H] = 0.10 +/- 0.06 based on 21 candidate members. Moreover, NGC 6705 shows no sign of the typical correlations or anti-correlations between Al, Mg, Si, and Na, which are expected in multiple populations. This is consistent with our cluster mass estimate, which is lower than the required mass limit proposed in the literature to develop multiple populations.
Autor principal: 
Cantat-Gaudin, T
Autor/es del IAA: 
Sampedro, L.; Costado, M. T.; Alfaro, E.
DOI: 
10.1051/0004-6361/201423851
Revista: 
ASTRONOMY & ASTROPHYSICS
Fecha de publicación: 
2014/09
Volumen: 
569
Tipo de documento: 
Article
Palabras clave: 
stars: abundances; open clusters and associations: general; open clusters and associations: individual: NGC 6705
Número de artículo: 
A17

MASSIV: Mass Assembly Survey with SINFONI in VVDS VI. Metallicity-related fundamental relations in star-forming galaxies at 1 < z < 2

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
MASSIV: Mass Assembly Survey with SINFONI in VVDS VI. Metallicity-related fundamental relations in star-forming galaxies at 1 < z < 2
Autores: 
Divoy, C; Contini, T; Perez-Montero, E; Queyrel, J; Epinat, B; Lopez-Sanjuan, C; Vergani, D; Moultaka, J; Amram, P; Garilli, B; Kissler-Patig, M; Le Fevre, O; Paioro, L; Tasca, LAM; Tresse, L; Perret, V
Resumen: 
Aims. The MASSIV (Mass Assembly Survey with SINFONI in VVDS) project aims at finding constraints on the different processes involved in galaxy evolution. This study proposes to improve understanding of the galaxy mass assembly through chemical evolution using metallicity as a tracer of the star formation and interaction history. Methods. We analysed the full sample of MASSIV galaxies for which a metallicity estimate has been possible, the 48 star-forming galaxies at z similar to 0 : 9 1 : 8, and computed the integrated values of some of the fundamental parameters, such as stellar mass, metallicity, and star formation rate (SFR). The sample of star-forming galaxies at similar redshifts from zCOSMOS was also combined with the MASSIV sample. We studied the cosmic evolution of the mass-metallicty relation, together with the effect of close environment and galaxy kinematics on this relation. We then focussed on the so-called fundamental metallicity relation and other relations between stellar mass, SFR, and metallicity. We investigated whether these relations are really fundamental, i.e. if they do not evolve with redshift. Results. The MASSIV galaxies follow the expected mass-metallicity relation for their median redshift. We find, however, a significant difference between isolated and interacting galaxies as found for local galaxies: interacting galaxies tend to have a lower metallicity. The study of the relation between stellar mass, SFR, and metallicity gives such large scattering for our sample, even combined with zCOSMOS, that it is difficult to confirm any fundamental relation.
Autor principal: 
Divoy, C
Autor/es del IAA: 
Perez-Montero, E.
DOI: 
10.1051/0004-6361/201423911
Revista: 
ASTRONOMY & ASTROPHYSICS
Fecha de publicación: 
2014/09
Volumen: 
569
Tipo de documento: 
Article
Palabras clave: 
galaxies: abundances; galaxies: evolution; galaxies: fundamental parameters; galaxies: high-redshift
Número de artículo: 
A64

Pair separation of magnetic elements in the quiet Sun

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
Pair separation of magnetic elements in the quiet Sun
Autores: 
Giannattasio, F; Berrilli, F; Biferale, L; Del Moro, D; Sbragaglia, M; Rubio, LB; Gosic, M; Suarez, DO
Resumen: 
The dynamic properties of the quiet Sun photosphere can be investigated by analyzing the pair dispersion of small-scale magnetic fields (i.e., magnetic elements). By using 25 h-long Hinode magnetograms at high spatial resolution (0 ''.3), we tracked 68 490 magnetic element pairs within a supergranular cell near the disk center. The computed pair separation spectrum, calculated on the whole set of particle pairs independently of their initial separation, points out what is known as a super-diffusive regime with spectral index gamma = 1.55 +/- 0.05, in agreement with the most recent literature, but extended to unprecedented spatial and temporal scales (from granular to supergranular). Furthermore, for the first time, we investigated here the spectrum of the mean square displacement of pairs of magnetic elements, depending on their initial separation r(0). We found that there is a typical initial distance above (below) which the pair separation is faster (slower) than the average. A possible physical interpretation of such a typical spatial scale is also provided.
Autor principal: 
Giannattasio, F
Autor/es del IAA: 
Bellot Rubio, L.; Gosic, M.
DOI: 
10.1051/0004-6361/201424380
Revista: 
ASTRONOMY & ASTROPHYSICS
Fecha de publicación: 
2014/09
Volumen: 
569
Tipo de documento: 
Article
Palabras clave: 
Sun: photosphere; Sun: magnetic fields; Sun: granulation
Número de artículo: 
A121

X-ray spectral variability of LINERs selected from the Palomar sample

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
X-ray spectral variability of LINERs selected from the Palomar sample
Autores: 
Hernandez-Garcia, L; Gonzalez-Martin, O; Masegosa, J; Marquez, I
Resumen: 
Context. Variability is a general property of active galactic nuclei (AGN). The way in which these changes occur at X-rays is not yet clearly understood. In the particular case of low-ionization nuclear emission line region (LINER) nuclei, variations on the timescales from months to years have been found for some objects, but the main driver of these changes is still debated. Aims. The main purpose of this work is to investigate the X-ray variability in LINERs, including the main driver of these variations, and to search for possible differences between type 1 and 2 objects. Methods. We examined the 18 LINERs in the Palomar sample with data retrieved from the Chandra and/or XMM-Newton archives that correspond to observations gathered at different epochs. All the spectra for the same object were fitted simultaneously to study long-term variations. The nature of the variability patterns were studied by allowing different parameters to vary during the spectral fit. Whenever possible, short-term variations from the analysis of the light curves and long-term UV variability were studied. Results. Short-term variations are not reported in X-rays. Three LINERs are classified as non-AGN candidates in X-rays, all of them are Compton-thick candidates; none of them show variations at these frequencies, and two of them vary in the UV. Long-term X-ray variations were analyzed in 12 out of 15 AGN candidates; about half of them showed variability (7 out of the 12). At UV frequencies, most of the AGN candidates with available data are variable (five out of six). Thus, 13 AGN candidates are analyzed at UV and/or X-rays, ten of which are variable at least in one energy band. None of the three objects that do not vary in X-rays have available UV data. This means that variability on long-timescales is very common in LINERs. These X-ray variations are mainly driven by changes in the nuclear power, while changes in absorptions are found only for NGC 1052. We do not find any difference between type 1 and 2 LINERs, neither in the number of variable cases (three out of five type 1 and four out of seven type 2 LINERs), nor in the nature of the variability pattern. We find indications of an anticorrelation between the slope of the power law, Gamma, and the Eddington ratio. Conclusions. LINERs are definitely variable sources irrespective of whether they are classified as optical type 1 or 2. Their BH masses, accretion rates, and variability timescales place them in the same plane as more powerful AGN at X-rays. However, our results suggest that the accretion mechanism in LINERs may be different. UV variations of some type 2 LINERs were found, this could support the hypothesis of a torus that disappears at low luminosities.
Autor principal: 
Hernandez-Garcia, L
Autor/es del IAA: 
Hernandez-Garcia, L.; Masegosa, J.; Marquez, I.
DOI: 
10.1051/0004-6361/201424140
Revista: 
ASTRONOMY & ASTROPHYSICS
Fecha de publicación: 
2014/09
Volumen: 
569
Tipo de documento: 
Article
Palabras clave: 
galaxies: active; X-rays: galaxies; ultraviolet: galaxies
Número de artículo: 
A26

Inclinations of small quiet-Sun magnetic features based on a new geometric approach

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
Inclinations of small quiet-Sun magnetic features based on a new geometric approach
Autores: 
Jafarzadeh, S; Solanki, SK; Lagg, A; Rubio, LRB; van Noort, M; Feller, A; Danilovic, S
Resumen: 
Context. High levels of horizontal magnetic flux have been reported in the quiet-Sun internetwork, often based on Stokes profile inversions. Aims. Here we introduce a new method for deducing the inclination of magnetic elements and use it to test magnetic field inclinations from inversions. Methods. We determine accurate positions of a set of small, bright magnetic elements in high spatial resolution images sampling different photospheric heights obtained by the SUNRISE balloon-borne solar observatory. Together with estimates of the formation heights of the employed spectral bands, these provide us with the inclinations of the magnetic features. We also compute the magnetic inclination angle of the same magnetic features from the inversion of simultaneously recorded Stokes parameters. Results. Our new, geometric method returns nearly vertical fields (average inclination of around 14 degrees with a relatively narrow distribution having a standard deviation of 6 degrees). In strong contrast to this, the traditionally used inversions give almost horizontal fields (average inclination of 75 +/- 8 degrees) for the same small magnetic features, whose linearly polarised Stokes profiles are adversely affected by noise. We show that for such magnetic features inversions overestimate the flux in horizontal magnetic fields by an order of magnitude. Conclusions. The almost vertical field of bright magnetic features from our geometric method is clearly incompatible with the nearly horizontal magnetic fields obtained from the inversions. This indicates that the amount of magnetic flux in horizontal fields deduced from inversions is overestimated in the presence of weak Stokes signals, in particular if Stokes Q and U are close to or under the noise level. Inversions should be used with great caution when applied to data with no clear Stokes Q and no U signal. By combining the proposed method with inversions we are not just improving the inclination, but also the field strength. This technique allows us to analyse features that are not reliably treated by inversions, thus greatly extending our capability to study the complete magnetic field of the quiet Sun.
Autor principal: 
Jafarzadeh, S
Autor/es del IAA: 
Bellot Rubio, L. R.
DOI: 
10.1051/0004-6361/201423414
Revista: 
ASTRONOMY & ASTROPHYSICS
Fecha de publicación: 
2014/09
Volumen: 
569
Tipo de documento: 
Article
Palabras clave: 
Sun: magnetic fields; Sun: photosphere; techniques: polarimetric
Número de artículo: 
A105

The dark nature of GRB 130528A and its host galaxy

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
The dark nature of GRB 130528A and its host galaxy
Autores: 
Jeong, S; Castro-Tirado, AJ; Bremer, M; Winters, JM; Gorosabel, J; Guziy, S; Pandey, SB; Jelinek, M; Sanchez-Ramirez, R; Sokolov, IV; Orekhova, NV; Moskvitin, AS; Tello, JC; Cunniffe, R; Lara-Gil, O; Oates, SR; Perez-Ramirez, D; Bai, J; Fan, Y; Wang, C; Park, IH
Resumen: 
Aims. We study the dark nature of GRB 130528A through multi-wavelength observations and conclude that the main reason for the optical darkness is local extinction inside of the host galaxy. Methods. Automatic observations were performed at the Burst Optical Observer and Transient Exploring System (BOOTES)-4 /MET robotic telescope. We also triggered target of opportunity (ToO) observations at Observatorio de Sierra Nevada (OSN), IRAM Plateau de Bure Interferometer (PdBI) and Gran Telescopio Canarias (GTC + OSIRIS). The host galaxy photometric observations in optical to near-infrared (nIR) wavelengths were achieved through large ground-based aperture telescopes, such as 10.4 m Gran Telescopio Canarias (GTC), 4.2 m William Herschel Telescope (WHT), 6 m Bolshoi Teleskop Alt-azimutalnyi (BTA) telescope, and 2 m Liverpool Telescope (LT). Based on these observations, spectral energy distributions (SED) for the host galaxy and afterglow were constructed. Results. Thanks to millimetre (mm) observations at PdBI, we confirm the presence of a mm source within the XRT error circle that faded over the course of our observations and identify the host galaxy. However, we do not find any credible optical source within early observations with BOOTES-4 /MET and 1.5 m OSN telescopes. Spectroscopic observation of this galaxy by GTC showed a single faint emission line that likely corresponds to [OII] 3727 angstrom at a redshift 1.250 +/- 0.001, implying a star formation rate (M-circle dot/yr) > 6.18 M-circle dot/yr without correcting for dust extinction. The probable line-of-sight extinction towards GRB130528A is revealed through analysis of the afterglow SED, resulting in a value of A(V)(GRB) >= 0.9 at the rest frame; this is comparable to extinction levels found among other dark GRBs. The SED of the host galaxy is explained well (chi(2)/d.o.f. = 0.564) by a luminous (M-B = -21.16), low-extinction (A(V) = 0, rest frame), and aged (2.6 Gyr) stellar population. We can explain this apparent contradiction in global and line-of-sight extinction if the GRB birth place happened to lie in a local dense environment. In light of having relatively small specific star formation rate similar to 5.3 M circle dot/yr (L/L*)(-1), this also could explain the age of the old stellar population of host galaxy.
Autor principal: 
Jeong, S
Autor/es del IAA: 
Jeong, S.; Castro-Tirado, A. J.; Gorosabel, J.; Jelinek, M.; Sanchez-Ramirez, R.; Tello, J. C.; Cunniffe, R.; Lara-Gil, O.; Oates, S. R.
DOI: 
10.1051/0004-6361/201423979
Revista: 
ASTRONOMY & ASTROPHYSICS
Fecha de publicación: 
2014/09
Volumen: 
569
Tipo de documento: 
Article
Palabras clave: 
gamma-ray burst: individual: GRB 130528A; techniques: photometric; techniques: spectroscopic; cosmology: observations
Número de artículo: 
A93

Trajectory, orbit, and spectroscopic analysis of a bright fireball observed over Spain on April 13, 2013

Submitted by admin on Thu, 01/01/1970 - 01:00
Titulo: 
Trajectory, orbit, and spectroscopic analysis of a bright fireball observed over Spain on April 13, 2013
Autores: 
Madiedo, JM; Trigo-Rodriguez, JM; Zamorano, J; Ana-Hernandez, L; Izquierdo, J; Ortiz, JL; Castro-Tirado, AJ; de Miguel, AS; Ocana, F; Pastor, S; de los Reyes, JA; Galad, D; de Guindos, E; Organero, F; Fonseca, F; Cabrera-Cano, J
Resumen: 
On April 13, 2013 a very bright fireball with an absolute magnitude of 13.0 +/- 0.5 was recorded over the center of Spain. This sporadic event, which was witnessed by numerous casual observers throughout the whole country, was imaged from seven meteor-observing stations operated by the Spanish Meteor Network (SPMN), and its emission spectrum was also obtained in the framework of our meteor spectroscopy campaign. The atmospheric trajectory of the bolide and the heliocentric orbit of the parent meteoroid are analyzed here. The spectrum reveals a chondritic nature for this particle, which was following a Jupiter family comet orbit before its encounter with the Earth. In addition, the emission spectrum of the meteoric afterglow was recorded during about 0.8 s. The main emission lines appearing in this signal were identified and their evolution with time is also discussed. Afterglow spectra are not abundant in the literature, and these can provide important clues about the physical proceses taking place in meteoric persistent trains.
Autor principal: 
Madiedo, JM
Autor/es del IAA: 
Ortiz, Jose L.; Castro-Tirado, Aberto J.
DOI: 
10.1051/0004-6361/201322120
Revista: 
ASTRONOMY & ASTROPHYSICS
Fecha de publicación: 
2014/09
Volumen: 
569
Tipo de documento: 
Article
Palabras clave: 
meteorites; meteors; meteoroids
Número de artículo: 
A104

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