http://sedici.unlp.edu.ar:80/handle/10915/167828 Wed, 21 Oct 2026 22:45:53 GMT 2026-10-21T22:45:53Z http://sedici.unlp.edu.ar:80/handle/10915/168116 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting Theγ -ray binary system PSR B1259-63/LS 2883 passed through periastron in May of 2014 and was the focus of intensive multiwavelength campaigns. During the previous periastron, a large flare was detected at GeV energies 30 days after the 2010 periastron passage by Fermi-LAT. This event was re-detected during 2014 at a similar orbital phase. In order to place better constraints on the behaviour of the circumstellar disc around periastron, we performed optical spectroscopy of the Hα and He i (λ6678) lines with the Southern African Large Telescope (SALT) from 33 days before until 78 days after the 2014 periastron. The Hα line remains single peaked through all observations, but with a noted asymmetry and variation in shape. The He i line remains double peaked and shows a variation in the relative peak heights. Both lines show an increase in the equivalent width which peaks after periastron. The line strengths before periastron are, however, weaker than were detected around the 2010 periastron, though are comparable after periastron. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168116 2016-01-01T00:00:00Z Theγ -ray binary system PSR B1259-63/LS 2883 passed through periastron in May of 2014 and was the focus of intensive multiwavelength campaigns. During the previous periastron, a large flare was detected at GeV energies 30 days after the 2010 periastron passage by Fermi-LAT. This event was re-detected during 2014 at a similar orbital phase. In order to place better constraints on the behaviour of the circumstellar disc around periastron, we performed optical spectroscopy of the Hα and He i (λ6678) lines with the Southern African Large Telescope (SALT) from 33 days before until 78 days after the 2014 periastron. The Hα line remains single peaked through all observations, but with a noted asymmetry and variation in shape. The He i line remains double peaked and shows a variation in the relative peak heights. Both lines show an increase in the equivalent width which peaks after periastron. The line strengths before periastron are, however, weaker than were detected around the 2010 periastron, though are comparable after periastron. http://sedici.unlp.edu.ar:80/handle/10915/168115 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting Active Galactic Nuclei (AGN) show variability on various time scales and present complex correlations between these variations at different wavelengths. Simultaneous multi-wavelength observations can therefore be used to place constraints on the different emission models. In May 2015 we began optical photometric monitoring of a subset of the known TeV emitting AGN using the Watcher Robotic Telescopes (Boyden Observatory, South Africa) to obtain long term photometric monitoring of these sources. Currently 17 targets are included in this monitoring campaign. The sources are observed once per night in the V, R & i’ bands, depending on observability and weather. The V, R and V-R light curves of four blazars are presented, all of which show variability which is consistent with previous studies. This demonstrates the feasibility of using the Watcher telescope to provide long term optical photometric monitoring of TeV blazars. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168115 2016-01-01T00:00:00Z Active Galactic Nuclei (AGN) show variability on various time scales and present complex correlations between these variations at different wavelengths. Simultaneous multi-wavelength observations can therefore be used to place constraints on the different emission models. In May 2015 we began optical photometric monitoring of a subset of the known TeV emitting AGN using the Watcher Robotic Telescopes (Boyden Observatory, South Africa) to obtain long term photometric monitoring of these sources. Currently 17 targets are included in this monitoring campaign. The sources are observed once per night in the V, R & i’ bands, depending on observability and weather. The V, R and V-R light curves of four blazars are presented, all of which show variability which is consistent with previous studies. This demonstrates the feasibility of using the Watcher telescope to provide long term optical photometric monitoring of TeV blazars. http://sedici.unlp.edu.ar:80/handle/10915/168114 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting The high energy radiation emitted by black hole X-ray binaries originates in an accretion disk, hence the variability of the lightcurves mirrors the dynamics of the disc. We study the time evolution of the emitted flux in order to find evidences, that low dimensional non-linear equations govern the accretion flow. Here we test the capabilities of our novel method to find chaotic behaviour on the two numerical time series describing the motion of a test particle around a black hole surrounded by a thin massive disc, one being regular and the other one chaotic. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168114 2016-01-01T00:00:00Z The high energy radiation emitted by black hole X-ray binaries originates in an accretion disk, hence the variability of the lightcurves mirrors the dynamics of the disc. We study the time evolution of the emitted flux in order to find evidences, that low dimensional non-linear equations govern the accretion flow. Here we test the capabilities of our novel method to find chaotic behaviour on the two numerical time series describing the motion of a test particle around a black hole surrounded by a thin massive disc, one being regular and the other one chaotic. http://sedici.unlp.edu.ar:80/handle/10915/168113 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting LS I +61 303 is a gamma-ray binary that exhibits an outburst at GHz frequencies each orbital cycle of 26.5 d and a superorbital modulation with a period of 4.6 yr. We have performed a detailed study of the low-frequency radio emission of LS I +61 303 by analyzing all the archival GMRT data at 150, 235 and 610 MHz and conducting regular LOFAR observations within the Radio Sky Monitor at 150 MHz. We have detected the source for the first time at 150 MHz, which is also the first detection of a gamma-ray binary at such low frequency. We have obtained the light-curves of the source at 150, 235 and 610 MHz, showing orbital and superorbital modulation. A comparison with contemporaneous RT and OVRO 15-GHz observations shows remarkable differences. At 15 GHz we see clear outbursts, whereas at low frequencies we observe variability with wider maxima. The light-curve at 235 MHz seems to be uncorrelated with the one at 610 MHz. We model the shifts between the maxima at different frequencies as due to changes in the physical parameters of the emitting region assuming either free-free absorption or synchrotron self-absorption, obtaining subrelativistic expansion velocities which are close to the stellar wind velocity for some of the cases. La lista completa de autores que integran el documento puede consultarse en el archivo. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168113 2016-01-01T00:00:00Z LS I +61 303 is a gamma-ray binary that exhibits an outburst at GHz frequencies each orbital cycle of 26.5 d and a superorbital modulation with a period of 4.6 yr. We have performed a detailed study of the low-frequency radio emission of LS I +61 303 by analyzing all the archival GMRT data at 150, 235 and 610 MHz and conducting regular LOFAR observations within the Radio Sky Monitor at 150 MHz. We have detected the source for the first time at 150 MHz, which is also the first detection of a gamma-ray binary at such low frequency. We have obtained the light-curves of the source at 150, 235 and 610 MHz, showing orbital and superorbital modulation. A comparison with contemporaneous RT and OVRO 15-GHz observations shows remarkable differences. At 15 GHz we see clear outbursts, whereas at low frequencies we observe variability with wider maxima. The light-curve at 235 MHz seems to be uncorrelated with the one at 610 MHz. We model the shifts between the maxima at different frequencies as due to changes in the physical parameters of the emitting region assuming either free-free absorption or synchrotron self-absorption, obtaining subrelativistic expansion velocities which are close to the stellar wind velocity for some of the cases. http://sedici.unlp.edu.ar:80/handle/10915/168112 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting Observations of the prompt emission of several Gamma Ray Bursts (GRBs) detected with the instruments on-board the Fermi Gamma ray Space Telescope (hereafter Fermi) as well with the Burst and Transient Source Experiment (BATSE) on-board the Compton Gamma Ray Observatory (CGRO) reveal deviations from the Band function to describe their spectra in the keV-MeV energy range. Analysis of Fermi data conclude that GRB prompt emission is adequately fitted with the simultaneous combination of three emission components: a thermal-like component interpreted as the jet photosphere, a non-thermal component interpreted as synchrotron radiation from particles within the jet and an additional non-thermal power-law (PL) function extending from low to high energies in gamma-rays, interpreted as Inverse Compton emission. In this work we present new analysis of three BATSE Bursts, namely GRBs 941017, 970111 and 990123. We show that the BATSE data are fully consistent with the model derived from Fermi data and that these three BATSE bursts also exhibit the three different components as reported from Fermi, noticing that they present similar spectral behaviour. In addition, the analysis using this three-component model during the prompt emission results in a strong correlation between the time-resolved luminosity and the corresponding rest-frame F spectral peak energy (LnTh i -EnTh;rest p;i relation). When fitted with a power law the relation have similar indices for all three bursts and these values are also in perfect agreement with the Fermi results. This points toward a possible universal emission process intrinsic to the non-thermal component of GRB prompt emission. Using this correlation we estimated the redshift for GRBs 941017 and 970111 using GRB990123 (with known redshift) as reference. The estimated redshifts for these bursts are typical values for long GRBs. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168112 2016-01-01T00:00:00Z Observations of the prompt emission of several Gamma Ray Bursts (GRBs) detected with the instruments on-board the Fermi Gamma ray Space Telescope (hereafter Fermi) as well with the Burst and Transient Source Experiment (BATSE) on-board the Compton Gamma Ray Observatory (CGRO) reveal deviations from the Band function to describe their spectra in the keV-MeV energy range. Analysis of Fermi data conclude that GRB prompt emission is adequately fitted with the simultaneous combination of three emission components: a thermal-like component interpreted as the jet photosphere, a non-thermal component interpreted as synchrotron radiation from particles within the jet and an additional non-thermal power-law (PL) function extending from low to high energies in gamma-rays, interpreted as Inverse Compton emission. In this work we present new analysis of three BATSE Bursts, namely GRBs 941017, 970111 and 990123. We show that the BATSE data are fully consistent with the model derived from Fermi data and that these three BATSE bursts also exhibit the three different components as reported from Fermi, noticing that they present similar spectral behaviour. In addition, the analysis using this three-component model during the prompt emission results in a strong correlation between the time-resolved luminosity and the corresponding rest-frame F spectral peak energy (LnTh i -EnTh;rest p;i relation). When fitted with a power law the relation have similar indices for all three bursts and these values are also in perfect agreement with the Fermi results. This points toward a possible universal emission process intrinsic to the non-thermal component of GRB prompt emission. Using this correlation we estimated the redshift for GRBs 941017 and 970111 using GRB990123 (with known redshift) as reference. The estimated redshifts for these bursts are typical values for long GRBs. http://sedici.unlp.edu.ar:80/handle/10915/168111 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting In general relativity, black holes are uniquely described by the Kerr metric and, according to the cosmic censorship conjecture, curvature singularities are always hidden behind an event horizon. We study the effect of an external magnetic field on the observed light curves of orbiting hot spots in thin accretion disks in Kerr spacetimes with (black holes) and without (super-extreme solutions) horizons. We employ a ray-tracing algorithm to calculate the light curves and power spectra of such hot spots for uniform and dipolar magnetic field configurations and show that the presence of a dipolar magnetic field produces potentially observable signatures which might be useful to probe the nature of compact objects and to test the cosmic censorship conjecture. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168111 2016-01-01T00:00:00Z In general relativity, black holes are uniquely described by the Kerr metric and, according to the cosmic censorship conjecture, curvature singularities are always hidden behind an event horizon. We study the effect of an external magnetic field on the observed light curves of orbiting hot spots in thin accretion disks in Kerr spacetimes with (black holes) and without (super-extreme solutions) horizons. We employ a ray-tracing algorithm to calculate the light curves and power spectra of such hot spots for uniform and dipolar magnetic field configurations and show that the presence of a dipolar magnetic field produces potentially observable signatures which might be useful to probe the nature of compact objects and to test the cosmic censorship conjecture. http://sedici.unlp.edu.ar:80/handle/10915/168110 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting Our motivation is to find blazars among the unidentified gamma-ray sources detected with Fermi-LAT in the crowed galactic plane region. Searching for photometric characteristics of blazars in the near- IR using data from the Vista Variables in the Vía Láctea (VVV survey), we aim to find a method to associate blazars to unidentified gamma-ray sources. We show preliminary results on the photometric properties of 4 gamma-ray blazars using the color-magnitude and color-color diagrams. We also compare these results with a different method based on mid-IR observations acquired with Wide-field Infrared Survey Explorer (WISE). Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168110 2016-01-01T00:00:00Z Our motivation is to find blazars among the unidentified gamma-ray sources detected with Fermi-LAT in the crowed galactic plane region. Searching for photometric characteristics of blazars in the near- IR using data from the Vista Variables in the Vía Láctea (VVV survey), we aim to find a method to associate blazars to unidentified gamma-ray sources. We show preliminary results on the photometric properties of 4 gamma-ray blazars using the color-magnitude and color-color diagrams. We also compare these results with a different method based on mid-IR observations acquired with Wide-field Infrared Survey Explorer (WISE). http://sedici.unlp.edu.ar:80/handle/10915/168109 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting It is expected that a large fraction of the unidentified sources detected at γ-rays are blazars. Through cross–correlation between the positions of unidentified objects from the 1FHL Fermi catalogue of γ-ray sources and the ROSAT, XMM Slew and Swift/XRT catalogues of X–ray objects, a sample of 38 associations was found with less than 10 arcsec of positional error. One third of them has recently been classified; the remainder, though believed to belong to the blazar class, has not yet been identified. Therefore, we aim at studying the optical spectra of the counterparts of these unidentified sources in order to find their redshifts and to analyse their nature and main spectral features. We present here our preliminary results from optical spectroscopic observations at the 3.58m Telescopio Nazionale Galileo (TNG) for 7 of them. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168109 2016-01-01T00:00:00Z It is expected that a large fraction of the unidentified sources detected at γ-rays are blazars. Through cross–correlation between the positions of unidentified objects from the 1FHL Fermi catalogue of γ-ray sources and the ROSAT, XMM Slew and Swift/XRT catalogues of X–ray objects, a sample of 38 associations was found with less than 10 arcsec of positional error. One third of them has recently been classified; the remainder, though believed to belong to the blazar class, has not yet been identified. Therefore, we aim at studying the optical spectra of the counterparts of these unidentified sources in order to find their redshifts and to analyse their nature and main spectral features. We present here our preliminary results from optical spectroscopic observations at the 3.58m Telescopio Nazionale Galileo (TNG) for 7 of them. http://sedici.unlp.edu.ar:80/handle/10915/168107 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting We investigate the effects predicted by an alternative model of gravity on the shape and trajectory of relativistic plasma ejections from the central region of Active Galactic Nuclei. Specifically, we calculate the effects of gravitational Lorentz-like forces that arise in the context of Moffat’s Scalar-Tensor-Vector Gravity (STVG), produced by a supermassive black hole on a relativistic plasma blob. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168107 2016-01-01T00:00:00Z We investigate the effects predicted by an alternative model of gravity on the shape and trajectory of relativistic plasma ejections from the central region of Active Galactic Nuclei. Specifically, we calculate the effects of gravitational Lorentz-like forces that arise in the context of Moffat’s Scalar-Tensor-Vector Gravity (STVG), produced by a supermassive black hole on a relativistic plasma blob. http://sedici.unlp.edu.ar:80/handle/10915/168106 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting The Fermi-LAT 2-year Source catalogue (2LAC) contains approximately 157 sources which are classified as AGN of unknown type (AGU) with no determined redshifts. We have identified a subset of these AGUsfor follow-up studies aiming to classify them and determine redshifts, utilizing South African observatories. Optical spectroscopic observations have been performed with the Southern African Large Telescope (SALT) and short term photometric variability of the sources was studied using the SAAO 1.9-m telescope. The results for five candidates are discussed. The spectra are mainly featureless as expected for BL Lacs, however, potential spectral features are present for some sources. Similarly, photometric monitoring shows potential variability, for certain sources. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168106 2016-01-01T00:00:00Z The Fermi-LAT 2-year Source catalogue (2LAC) contains approximately 157 sources which are classified as AGN of unknown type (AGU) with no determined redshifts. We have identified a subset of these AGUsfor follow-up studies aiming to classify them and determine redshifts, utilizing South African observatories. Optical spectroscopic observations have been performed with the Southern African Large Telescope (SALT) and short term photometric variability of the sources was studied using the SAAO 1.9-m telescope. The results for five candidates are discussed. The spectra are mainly featureless as expected for BL Lacs, however, potential spectral features are present for some sources. Similarly, photometric monitoring shows potential variability, for certain sources. http://sedici.unlp.edu.ar:80/handle/10915/168104 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting The active radio galaxy IC310 is one of brightest objects of the Perseus cluster in the radio wavelengths and X-rays. This source has been detected in radio, X rays and rays. Recently, a -ray flux at TeV energies was detected by the MAGIC Telescopes. We introduce a lepto-hadronic model to describe the spectral energy distribution (SED), radio to GeV photons as synchrotron self-Compton (SSC) emission and TeV photons as the result of the decay of neutral pions resulting from p interactions. For the p interactions, we assume that the seed photons are those around the second SSC peak. We show that this hadronic model describes successfully the TeV -ray photons at low state of this radio galaxy. Additionally, we compute the number of neutrinos expected to be detected in the IceCube neutrino telescope. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168104 2016-01-01T00:00:00Z The active radio galaxy IC310 is one of brightest objects of the Perseus cluster in the radio wavelengths and X-rays. This source has been detected in radio, X rays and rays. Recently, a -ray flux at TeV energies was detected by the MAGIC Telescopes. We introduce a lepto-hadronic model to describe the spectral energy distribution (SED), radio to GeV photons as synchrotron self-Compton (SSC) emission and TeV photons as the result of the decay of neutral pions resulting from p interactions. For the p interactions, we assume that the seed photons are those around the second SSC peak. We show that this hadronic model describes successfully the TeV -ray photons at low state of this radio galaxy. Additionally, we compute the number of neutrinos expected to be detected in the IceCube neutrino telescope. http://sedici.unlp.edu.ar:80/handle/10915/168088 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting We report on a multiwavelength survey of a sample of 42 flat-spectrum radio-loud narrow-line Seyfert 1 galaxies (RLNLS1s). This is the largest known sample of this type of active galactic nucleus (AGN) to date. We found that 17% of sources were detected at high-energy gamma rays (E > 100 MeV), and 90% at X-rays (0:3 - 10 keV). The masses of the central black holes are in the range ∼ 10⁶⁻⁸M⊙ , smaller than the values of blazars. The disk luminosities are about 1 - 49% of the Eddington value, with one outlier at 0.3%, comparable with the luminosities observed in flat-spectrum radio quasars (FSRQs). The jet powers are ∼ 10⁴²⁻⁴⁶ erg s⁻¹, comparable with BL Lac Objects, yet relatively smaller than FSRQs. However, once renormalized by the mass of the central black hole, the jet powers of RLNLS1s, BL Lacs, and FSRQs are consistent each other, indicating the scalability of the jets. We found episodes of extreme variability at high energies on time scales of hours. In some cases, dramatic spectral and flux changes are interpreted as the interplay between the relativistic jet and the accretion disk. We conclude that, despite the distinct observational properties, the central engines of RLNLS1s are similar to those of blazars. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168088 2016-01-01T00:00:00Z We report on a multiwavelength survey of a sample of 42 flat-spectrum radio-loud narrow-line Seyfert 1 galaxies (RLNLS1s). This is the largest known sample of this type of active galactic nucleus (AGN) to date. We found that 17% of sources were detected at high-energy gamma rays (E > 100 MeV), and 90% at X-rays (0:3 - 10 keV). The masses of the central black holes are in the range ∼ 10⁶⁻⁸M⊙ , smaller than the values of blazars. The disk luminosities are about 1 - 49% of the Eddington value, with one outlier at 0.3%, comparable with the luminosities observed in flat-spectrum radio quasars (FSRQs). The jet powers are ∼ 10⁴²⁻⁴⁶ erg s⁻¹, comparable with BL Lac Objects, yet relatively smaller than FSRQs. However, once renormalized by the mass of the central black hole, the jet powers of RLNLS1s, BL Lacs, and FSRQs are consistent each other, indicating the scalability of the jets. We found episodes of extreme variability at high energies on time scales of hours. In some cases, dramatic spectral and flux changes are interpreted as the interplay between the relativistic jet and the accretion disk. We conclude that, despite the distinct observational properties, the central engines of RLNLS1s are similar to those of blazars. http://sedici.unlp.edu.ar:80/handle/10915/168087 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting The wind-collision region of the system HD 93129A was recently resolved. This system is the most massive known binary in our Galaxy. We aim to gain insight into the physics taking place in such a system, particularly in the acceleration process(es). We explored the broadband non-thermal emission for different injection spectra of relativistic particles accelerated in the wind-collision region. We developed a model that computes the evolution of the particle energy distribution taking into account different energy losses while the particles stream along the fluid lines in the shocked region. Such model was able to reproduce the available radio data. Also, for different scenarios we predicted the evolution of the cosmic-rays energy distribution and the radiative output in future epochs, when the stars come closer. With further observational data it will be possible to determine the injection spectrum and acceleration efficiency of relativistic particles in HD 93129A. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168087 2016-01-01T00:00:00Z The wind-collision region of the system HD 93129A was recently resolved. This system is the most massive known binary in our Galaxy. We aim to gain insight into the physics taking place in such a system, particularly in the acceleration process(es). We explored the broadband non-thermal emission for different injection spectra of relativistic particles accelerated in the wind-collision region. We developed a model that computes the evolution of the particle energy distribution taking into account different energy losses while the particles stream along the fluid lines in the shocked region. Such model was able to reproduce the available radio data. Also, for different scenarios we predicted the evolution of the cosmic-rays energy distribution and the radiative output in future epochs, when the stars come closer. With further observational data it will be possible to determine the injection spectrum and acceleration efficiency of relativistic particles in HD 93129A. http://sedici.unlp.edu.ar:80/handle/10915/168086 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting In the present work it is investigated the magnetic luminosity produced by Kerr black holes in active galactic nuclei (AGNs). Some comparison is made between the results for some black hole masses with spins in the range 0:44 < a < 0:80 and the upper limit of ultra high energy cosmic ray (UHECR) luminosities, calculated from observed integral flux of GeV-TeV gamma rays for nine UHECR AGN candidates with the same masses considered theoretically. We find that the calculated theoretical range of magnetic luminosities from AGNs coincides with the calculated UHECR luminosity. It is argued that this result can possibly shed some light in the phenomenology of AGN magnetic properties in manner to explain some of the requisite conditions to proper accelerate the highest energy cosmic rays. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168086 2016-01-01T00:00:00Z In the present work it is investigated the magnetic luminosity produced by Kerr black holes in active galactic nuclei (AGNs). Some comparison is made between the results for some black hole masses with spins in the range 0:44 < a < 0:80 and the upper limit of ultra high energy cosmic ray (UHECR) luminosities, calculated from observed integral flux of GeV-TeV gamma rays for nine UHECR AGN candidates with the same masses considered theoretically. We find that the calculated theoretical range of magnetic luminosities from AGNs coincides with the calculated UHECR luminosity. It is argued that this result can possibly shed some light in the phenomenology of AGN magnetic properties in manner to explain some of the requisite conditions to proper accelerate the highest energy cosmic rays. http://sedici.unlp.edu.ar:80/handle/10915/168052 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting We present results from an optical polarimetric study of blazars that have been detected at very high-energy (VHE) -γ rays. We look for short time-scale fluctuations (i.e., microvariability) either/both in their polarisation percent or position angle in the B and R optical bands. Spurious effects introduced by light contamination from the host galaxy, especially due to seeing FWHM variations, are quantitatively analysed. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168052 2016-01-01T00:00:00Z We present results from an optical polarimetric study of blazars that have been detected at very high-energy (VHE) -γ rays. We look for short time-scale fluctuations (i.e., microvariability) either/both in their polarisation percent or position angle in the B and R optical bands. Spurious effects introduced by light contamination from the host galaxy, especially due to seeing FWHM variations, are quantitatively analysed. http://sedici.unlp.edu.ar:80/handle/10915/168051 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting Ultrahigh energy cosmic rays (UHECRs) are problably originated in extragalactic sources as, e.g., Active Galactic Nuclei (AGNs). In the present work it is proposed an approach to calculate bounds on the AGN luminosity fraction that can be converted in such UHECRs. This result comes from two separated points of view: (i) the intrinsic mechanism powered by central black holes to produce the AGN luminosity and (ii) the observation of UHECRs and gamma-rays from ground experiments to reconstruct proton luminosities of a given AGN source. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168051 2016-01-01T00:00:00Z Ultrahigh energy cosmic rays (UHECRs) are problably originated in extragalactic sources as, e.g., Active Galactic Nuclei (AGNs). In the present work it is proposed an approach to calculate bounds on the AGN luminosity fraction that can be converted in such UHECRs. This result comes from two separated points of view: (i) the intrinsic mechanism powered by central black holes to produce the AGN luminosity and (ii) the observation of UHECRs and gamma-rays from ground experiments to reconstruct proton luminosities of a given AGN source. http://sedici.unlp.edu.ar:80/handle/10915/168050 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting The Pierre Auger Observatory, located in the province of Mendoza, Argentina, was built for detecting and studying ultra-high energy cosmic rays. The Observatory was designed as a hybrid detector covering an area of 3000 km2 and it has been taking data for more than ten years. In this report a selection of the latest results is presented. These include the observation of the flux evolution and suppression at the highest energies, inferred trends on composition with energy, bounds on photons and neutrinos, and arrival direction studies. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168050 2016-01-01T00:00:00Z The Pierre Auger Observatory, located in the province of Mendoza, Argentina, was built for detecting and studying ultra-high energy cosmic rays. The Observatory was designed as a hybrid detector covering an area of 3000 km2 and it has been taking data for more than ten years. In this report a selection of the latest results is presented. These include the observation of the flux evolution and suppression at the highest energies, inferred trends on composition with energy, bounds on photons and neutrinos, and arrival direction studies. http://sedici.unlp.edu.ar:80/handle/10915/168049 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting High-energy observations of extreme BL Lac objects, such as 1ES0229+200 or 1ES 0347–121, recently focused interest both for blazar and jet physics and for the implication on the extragalactic background light and intergalactic magnetic field estimate. Moreover, their enigmatic properties have been interpreted in a scenario in which their primary highenergy output is through a beam of high-energy hadrons. However, despite their possible important role in all these topics, the number of these extreme highly peaked BL Lac objects (EHBL) is still rather small. Aiming at increase their number, we selected a group of EHBL candidates considering those undetected (or only barely detected) by the LAT onboard Fermi and characterized by a high X-ray versus radio flux ratio. We assembled the multi-wavelength spectral energy distribution of the resulting 9 sources, using available archival data of Swift, GALEX, and Fermi satellites, confirming their nature. Through a simple one-zone synchrotron self-Compton model we estimate the expected very high energy flux, finding that in the majority of cases it is within the reach of present generation of Cherenkov arrays or of the forthcoming CTA. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168049 2016-01-01T00:00:00Z High-energy observations of extreme BL Lac objects, such as 1ES0229+200 or 1ES 0347–121, recently focused interest both for blazar and jet physics and for the implication on the extragalactic background light and intergalactic magnetic field estimate. Moreover, their enigmatic properties have been interpreted in a scenario in which their primary highenergy output is through a beam of high-energy hadrons. However, despite their possible important role in all these topics, the number of these extreme highly peaked BL Lac objects (EHBL) is still rather small. Aiming at increase their number, we selected a group of EHBL candidates considering those undetected (or only barely detected) by the LAT onboard Fermi and characterized by a high X-ray versus radio flux ratio. We assembled the multi-wavelength spectral energy distribution of the resulting 9 sources, using available archival data of Swift, GALEX, and Fermi satellites, confirming their nature. Through a simple one-zone synchrotron self-Compton model we estimate the expected very high energy flux, finding that in the majority of cases it is within the reach of present generation of Cherenkov arrays or of the forthcoming CTA. http://sedici.unlp.edu.ar:80/handle/10915/168048 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting In the last years the presence of synchrotron emission has been proposed in a handful of protostellar jets. However, it is yet unclear how this "slow" jets could be able to accelerate particles up to relativistic velocities in order to emit detectable synchrotron emission. One of the most likely possibilities is that particles are accelerated in strong shocks of the jet against the dense envelopes surrounding the protostar. Particle acceleration has been studied in several astrophysical systems (AGN’s, microquasars, SN, massive binaries, etc.), nevertheless, in YSO is a fairly new phenomenon. Here, we present the analysis of high sensitivity continuum and linearly polarized images at several frequencies of one of the most characteristic non-thermal protostellar jets: The Triple Radio Source in Serpens. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168048 2016-01-01T00:00:00Z In the last years the presence of synchrotron emission has been proposed in a handful of protostellar jets. However, it is yet unclear how this "slow" jets could be able to accelerate particles up to relativistic velocities in order to emit detectable synchrotron emission. One of the most likely possibilities is that particles are accelerated in strong shocks of the jet against the dense envelopes surrounding the protostar. Particle acceleration has been studied in several astrophysical systems (AGN’s, microquasars, SN, massive binaries, etc.), nevertheless, in YSO is a fairly new phenomenon. Here, we present the analysis of high sensitivity continuum and linearly polarized images at several frequencies of one of the most characteristic non-thermal protostellar jets: The Triple Radio Source in Serpens. http://sedici.unlp.edu.ar:80/handle/10915/168047 Objeto de conferencia High-Energy Phenomena tn Relativistic Outflows V (La Plata, 5 al 8 de octubre de 2015); https://sedici.unlp.edu.ar/handle/10915/167830; Proceedings of the High-Energy Phenomena in Relativistic Outflows V meeting In this work we combine SEDs, radio maps and polarization observations to understand the emission mechanisms in Cygnus X-1. Our radiative model indicates that the MeV emission originates in the jet and that all the very high-energy emission is from hadronic origin. We also performed a synthetic radio map that suggests that our description of the magnetic field should be improved, since it leads to a very compact emission region. In order to choose the most suitable magnetic field geometry, we investigated the polarization in X-rays and we found that a very simple geometry can explain the high levels of polarization reported by other authors. Fri, 01 Jan 2016 00:00:00 GMT http://sedici.unlp.edu.ar:80/handle/10915/168047 2016-01-01T00:00:00Z In this work we combine SEDs, radio maps and polarization observations to understand the emission mechanisms in Cygnus X-1. Our radiative model indicates that the MeV emission originates in the jet and that all the very high-energy emission is from hadronic origin. We also performed a synthetic radio map that suggests that our description of the magnetic field should be improved, since it leads to a very compact emission region. In order to choose the most suitable magnetic field geometry, we investigated the polarization in X-rays and we found that a very simple geometry can explain the high levels of polarization reported by other authors.