J. A. de Diego
A5042727116- Gamma-ray bursts and supernovae
- SAS software applications and methods
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Spectroscopy and Chemometric Analyses
- Radio Astronomy Observations and Technology
- Trypanosoma species research and implications
- Solar and Space Plasma Dynamics
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Adaptive optics and wavefront sensing
- Astrophysics and Star Formation Studies
- Research on Leishmaniasis Studies
- Particle Accelerators and Free-Electron Lasers
- Gyrotron and Vacuum Electronics Research
- Metallic Glasses and Amorphous Alloys
- Spectroscopy and Laser Applications
- Scientific Research and Discoveries
- Computational Physics and Python Applications
- Calibration and Measurement Techniques
- Cosmology and Gravitation Theories
Universidad Nacional Autónoma de México
2014-2024
Universidad de Cantabria
2004-2022
Instituto de Física de Cantabria
2022
Instituto de Astrofísica de Canarias
1990-2021
Nanjing University
2000-2021
Universidad de La Laguna
1990-2016
University of California, Santa Cruz
2014-2015
Consejo Superior de Investigaciones Científicas
1996-2013
Universidad Autónoma de Madrid
1996-2012
Universidad de Granada
2005-2009
We present UBVRI light curves of BL Lacertae from May 2000 to January 2001, obtained by 24 telescopes in 11 countries. More than 15000 observations were performed that period, which was the extension Whole Earth Blazar Telescope (WEBT) campaign originally planned for July-August 2000. Rapid flux oscillations are all time, involving variations up a few tenths mag on hour time scales, and witnessing an intense intraday activity this source. Colour indexes have been derived coupling highest...
BL Lacertae has been the target of four observing campaigns by Whole Earth Blazar Telescope (WEBT) collaboration. In this paper we present $UBVRI$ light curves obtained WEBT from 1994 to 2002, including last, extended Lac 2001 campaign. A total about 7500 optical observations performed 31 telescopes Japan Mexico have collected, be added $\sim 15600$ Campaign 2000. All these data allow one follow source emission behaviour with unprecedented detail. The analysis colour indices reveals that...
Literature on optical and infrared microvariability in Active Galactic Nuclei (AGNs) reflects a diversity of statistical tests strategies to detect tiny variations the lightcurves these sources. Comparison between results obtained using different methodologies is difficult, pros cons each method are often badly understood or even ignored. Even worse, not properly tested becoming more common, biased may be misleading realize origin AGN microvariability. This paper intends point future...
We present optical and near-infrared (NIR) photometry for three gamma-ray burst supernovae (GRB-SNe): GRB 120729A, 130215A / SN 2013ez 130831A 2013fu. In the case of 2013ez, we also spectroscopy at t-t0=16.1 d, which covers rest-frame 3000-6250 Angstroms. Based on Fe II (5169) Si (II) (6355), our spectrum indicates an unusually low expansion velocity 4000-6350 km/s, lowest ever measured a GRB-SN. Additionally, determined brightness shape each accompanying relative to template supernova (SN...
The Reionization and Transients InfraRed camera (RATIR) is a simultaneous optical/NIR multi-band imaging which 100% time-dedicated to the followup of Gamma-ray Bursts. mounted on 1.5-meter Johnson telescope Mexican Observatorio Astronomico Nacional Sierra San Pedro Martir in Baja California. With rapid slew capability autonomous interrupt capabilities, system will image GRBs 6 bands (i, r, Z, Y, J, H) within minutes receiving satellite position, detecting optically faint afterglows NIR...
We report here the discovery by Intermediate Palomar Transient Factory (iPTF) of iPTF14yb, a luminous ($M_{r}\approx-27.8$ mag), cosmological (redshift 1.9733), rapidly fading optical transient. demonstrate, based on probabilistic arguments and comparison with broader population, that iPTF14yb is afterglow long-duration gamma-ray burst GRB 140226A. This marks first unambiguous prior to (and thus entirely independent of) an associated high-energy trigger. estimate rate iPTF14yb-like sources...
We present optical and near-infrared light curves spectra of SN 2013dx, associated with the nearby (redshift 0.145) gamma-ray burst GRB 130702A. The prompt isotropic energy released from 130702A is measured to be $E_{\gamma,iso}=6.4_{-1.0}^{+1.3}\times10^{50}$erg (1keV-10MeV in rest frame), placing it intermediate between low-luminosity GRBs like 980425/SN 1998bw broader cosmological population. compare observed $g'r'i'z'$ 2013dx a template, finding that evolves ~20% faster (steeper rise...
We present the results of extensive multiband intranight optical monitoring BL Lacertae during 2010–2012. was very active in this period and showed intense variability almost all wavelengths. extensively observed it for a total 38 nights; on 26 them, observations were done quasi-simultaneously B, V, R I bands (totalling 113 light curves), with an average sampling interval around 8 min. significant variations hour-like time-scales 19 nights different bands. did not find any evidence...
Historically, 3C 66A has been considered a relative quiescent blazar. For that reason, was selected as comparison source for OJ 287 in the OJ-94 project. However, after more detailed observation it turns out variability of itself is very interesting. We have analyzed entire project data set from fall 1993 to spring 1998 by using structure function analysis, Deeming periodograms, Scargle and folded light curves. Here we present first preliminary evidence 65 day period observed during bright...
BL Lacertae was the target of an extensive multiwavelength monitoring campaign in second half 2000. Simultaneous or quasi-simultaneous observations were taken at radio (UMRAO and Metsaehovi) optical(WEBT collaboration) frequencies, X-rays (BeppoSAX RXTE), VHE gamma-rays (HEGRA). The WEBT optical achieved unprecedented time coverage, virtually continuous over several 10 - 20 hour segments. It revealed intraday variability on scales ~ 1.5 hours evidence for spectral hardening associated with...
We present an analysis of the emitters ( and from OTELO survey, in order to characterize star formation properties low-mass galaxies ($<10^9$ M_⊙ stellar masses). calculated specific rate function, mass and, by integrating them, associated densities for both quantities: density density. obtained history our sample fitting spectral energy distribution galaxies. also compared results with those literature at different regimes redshifts. The do not depend on redshift, contrary behaviour...
We present intensive optical, infrared, and radio monitoring observations of the BL Lac object OJ 287, taken between years 1993-1998. Two large optical outbursts were detected at predicted times in November 1994 December 1995. The detection these supports binary black hole model for 287. Optical polarisation show variability degree position angle, very similar to those observed during 1983/84 outburst angles behaviour observations, indicating that, least, magnetic field orientations bands...
Microvariability consists of small timescale variations low amplitude in the photometric light curves quasars and represents an important tool to investigate their inner core. Detection quasar microvariations is challenging because non-periodicity, as well need for high monitoring frequency a signal-to-noise ratio. Statistical tests developed analysis differential usually show either power or reliability, both. In this paper we compare two statistical procedures perform on several stars with...
We present optical and near-infrared (NIR) photometry of 28 gamma-ray bursts (GRBs) detected by the Swift satellite rapidly observed Reionization Transients Infrared/Optical (RATIR) camera. compare flux at fiducial times 5.5 11 h after high-energy trigger to that in X-ray regime quantify darkness. 46 ± 9 per cent (13/28) all our sample 55 10 (13/26) long GRBs are optically dark, which is statistically consistently with previous studies. Fitting RATIR NIR spectral energy distributions 19...
Gamma-ray bursts (GRBs) are the most luminous explosions in Universe, yet nature and physical properties of their energy sources far from understood. Very important clues, however, can be inferred by studying afterglows these events. We present optical X-ray observations GRB 130831A obtained Swift, Chandra, Skynet, Reionization And Transients Infra-Red camera, Maidanak, International Scientific Optical-Observation Network, Nordic Optical Telescope, Liverpool Telescope Gran Telescopio...
We have performed photometric optical observations of a sample 17 core-dominated radio-loud quasars (CRLQs) and radio-quiet (RQQs). The aims were to confirm the existence microvariations in strictly objects compare properties variations both types quasars. Great care was taken avoid selection effects spurious biases samples. present new observational statistical procedure for searching microvariability, based on analysis variance. results show that RQQs may be as frequent CRLQs. implications...
The BL Lac object 3C 66A was the target of an extensive multiwavelength monitoring campaign from July 2003 through April 2004, involving observations throughout electromagnetic spectrum. Radio, infrared, and optical were carried out by WEBT-ENIGMA collaboration. At higher energies, observed in X-rays (RXTE), at very-high-energy (VHE) gamma-rays (STACEE, VERITAS). In addition, source has been with VLBA 9 epochs period September - December including 3 contemporaneous core campaign.The WEBT...
Microvariations probe the physics and internal structure of quasars. Unpredictability small flux variations make this phenomenon elusive difficult to detect. Variance-based probes such as C F tests, or a combination both, are popular methods compare light curves quasar comparison star. Recently, detection claims in some studies have depended on agreement results two instances F-test, for rejecting non-variation null hypothesis. However, C-test is non-reliable statistical procedure, F-test...
Abstract We investigate the prompt emission and afterglow properties of short-duration gamma-ray burst (sGRB) 130603B another eight sGRB events during 2012–2015, observed by several multiwavelength facilities including Gran Canarias Telescope 10.4 m telescope. Prompt high energy data were obtained INTEGRAL-SPI-ACS, Swift-BAT, Fermi-GBM satellites. The INTEGRAL in range 0.1–10 MeV for 130603B, 140606A, 140930B, 141212A, 151228A do not show any signature extended or precursor activity their...
Quasars accreting matter at very high rates (known as extreme Population A [xA] quasars, possibly associated with super-Eddington massive black holes) may provide a new class of distance indicators covering cosmic epochs from present day up to less than 1 Gyr the Big Bang. At more fundamental level, xA quasars are special interest in studies physics AGNs and host galaxy evolution. However, their observational properties largely unknown. can be identified relatively large numbers major...
Four iron superoxide dismutase (SODI, SODII, SODIII, and SODIV) activities with pI values of 6.9, 6.8, 5.25, 3.8, respectively, were isolated from epimastigote forms the Maracay strain Trypanosoma cruzi cultivated at 28°C in Grace’s medium supplemented 10% heat-inactivated fetal bovine serum. The activity SODe (pI 3.8), which coincides that SODIV, was detected without serum T. epimastigotes for 24 hours 28°C. SODe, excreted into by parasite, immunogenic antibodies to a dilution 1:2,500...
Objectives . To evaluate the potential of iron-oxide dismutase excreted (SODeCRU) by T. cruzi as antigen fraction in serodiagnosis Chagas disease and compile new epidemiological data on seroprevalence this suburban population city Santiago de Querétaro (Mexico). Design Methods 258 human sera were analyzed techniques ELISA Western blot using homogenate SODeCRU. Results A total 31 positive against ELISA/SODeCRU (12.4%), while 30 proved WB/SODeCRU (11.6%). The comparison between technique WB...