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158 results on '"J A Acosta-Pulido"'

151. Accretion tori and cones of ionizing radiation in Seyfert galaxies

Author

Andrew S. Wilson, Massimo Calvani, J. A. Acosta-Pulido, and Ismael Perez-Fournon

Subjects
Physics, Solar mass, Supermassive black hole, Active galactic nucleus, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Photoionization, Galaxy, Accretion (astrophysics), Black hole, Intermediate polar, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

The photoionization of extended narrow-line regions in Seyfert galaxies by the radiation produced in a thick accretion disk is studied. The emission-line spectrum is calculated for a range of black hole masses, varying the values of the ionization parameter and the disk size. It is found that models with a million solar masses fit observations of very large accretion disk sizes, while models with 10 million solar masses fit them better with smaller disks. The latter models are preferable since they have lower super-Eddington accretion rates.

Published
1990
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152. A near-infrared study of the multiphase outflow in the type-2 quasar J1509+0434

Author

Clive Tadhunter, M Fernández-Torreiro, Claudia Cicone, C González-Fernández, C. Ramos Almeida, J. A. Acosta-Pulido, and Apollo - University of Cambridge Repository

Subjects
Gran Telescopio Canarias, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Type (model theory), 01 natural sciences, Ionization, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, 010308 nuclear & particles physics, Near-infrared spectroscopy, Astronomy and Astrophysics, Quasar, Mass ratio, Astrophysics - Astrophysics of Galaxies, Galaxy, galaxies: quasars, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Outflow, Astrophysics::Earth and Planetary Astrophysics, galaxies: nuclei
Abstract

Based on new near-infrared spectroscopic data from the instrument EMIR on the 10.4 m Gran Telescopio Canarias (GTC) we report the presence of an ionized and warm molecular outflow in the luminous type-2 quasar J150904.22+043441.8 (z = 0.1118). The ionized outflow is faster than its molecular counterpart, although the outflow sizes that we derive for them are consistent within the errors (1.34$\pm$0.18 kpc and 1.46$\pm$0.20 kpc respectively). We use these radii, the broad emission-line luminosities and in the case of the ionized outflow, the density calculated from the trans-auroral [OII] and [SII] lines, to derive mass outflow rates and kinetic coupling efficiencies. Whilst the ionized and warm molecular outflows represent a small fraction of the AGN power ($\leq$0.033% and 0.0001% of L$_{bol}$ respectively), the total molecular outflow, whose mass is estimated from an assumed warm-to-cold gas mass ratio of 6$\times10^{-5}$, has a kinetic coupling efficiency of $\sim$1.7%L$_{bol}$. Despite the large uncertainty, this molecular outflow represents a significant fraction of L$_{bol}$ and it could potentially have a significant impact on the host galaxy. In addition, the quasar spectrum reveals bright and patchy narrow Pa$\alpha$ emission extending out to 4 arcsec (8 kpc) South-East and North-West from the active nucleus., Comment: 6 pages, 4 figures, accepted for publication in MNRAS Letters

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153. The Weakening Outburst of the Young Eruptive Star V582 Aur.

Author

G. Zsidi, P. Ábrahám, J. A. Acosta-Pulido, Á. Kóspál, M. Kun, Zs. M. Szabó, A. Bódi, B. Cseh, N. Castro Segura, O. Hanyecz, B. Ignácz, Cs. Kalup, L. Kriskovics, L. Mészáros, A. Ordasi, A. Pál, K. Sárneczky, B. Seli, Á. Sódor, and R. Szakáts

Subjects
DUST explosions, STARS, DUST
Abstract

V582 Aur is a pre-main-sequence FU Orionis type eruptive star, which entered a brightness minimum in 2016 March due to changes in the line-of-sight extinction. Here, we present and analyze new optical B, V, RC, and IC band multiepoch observations and new near-infrared J, H, and KS band photometric measurements from 2018 January–2019 February, as well as publicly available midinfrared Wide-field Infrared Survey Explorer (WISE) data. We found that the source shows a significant optical–near-infrared variability, and the current brightness minimum has not completely finished yet. If the present dimming originates from the same orbiting dust clump that caused a similar brightness variation in 2012, then our results suggest a viscous spreading of the dust particles along the orbit. Another scenario is that the current minimum is caused by a dust structure, that is entering and leaving the inner part of the system. The WISE measurements could be consistent with this scenario. Our long-term data, as well as an accretion disk modeling hint at a general fading of V582 Aur, suggesting that the source will reach the quiescent level in ∼80 yr. [ABSTRACT FROM AUTHOR]

Published
2019
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155. 3D kinematics of the near-IR HH 223 outflow in L723

Author

G. Gómez, Begoña García-Lorenzo, J. A. Acosta-Pulido, Roberto López, Robert Estalella, and Universitat de Barcelona

Subjects
Physics, Infrared, business.industry, Young stellar object, FOS: Physical sciences, Astronomy and Astrophysics, Kinematics, Astrophysics, Stars, Spectral line, Estels, Astrophysical jets, Optics, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Radioastronomia, Jets (Astrofísica), William Herschel Telescope, Outflow, Radio astronomy, business, Spectrograph, Solar and Stellar Astrophysics (astro-ph.SR), Line (formation)
Abstract

In this work we derive the full 3-D kinematics of the near-infrared outflow HH 223, located in the dark cloud Lynds 723 (L723), where a well-defined quadrupolar CO outflow is found. HH 223 appears projected onto the two lobes of the east-west CO outflow. The radio continuum source VLA 2, towards the centre of the CO outflow, harbours a multiple system of low-mass young stellar objects. One of the components has been proposed to be the exciting source of the east-west CO outflow. From the analisys of the kinematics, we get further evidence on the relationship between the near-infrared and CO outflows and on the location of their exciting source. The proper motions were derived using multi-epoch, narrow-band H$_2$ (2.122 $\mu$m line) images. Radial velocities were derived from the 2.122 $\mu$m line of the spectra. Because of the extended (~5 arcmin), S-shaped morphology of the target, the spectra were obtained with the Multi-Object-Spectroscopy (MOS) observing mode using the instrument LIRIS at the 4.2m William Herschel Telescope. To our knowledge, this work is the first time that MOS observing mode has been successfully used in the near infrared range for an extended target., Comment: 16 pages, 13 figures; accepted in MNRAS

156. Multiwavelength observations of a VHE gamma-ray flare from PKS 1510-089 in 2015

Author

I. Snidaric, M. Strzys, M. Vazquez Acosta, J. A. Acosta-Pulido, Vishal Bala, B. De Lotto, J. Palacio, Julian Sitarek, L. Nogués, E. Colombo, B. Biasuzzi, M. Makariev, C. Fruck, D. Nakajima, T. Toyama, Diego F. Torres, Abelardo Moralejo, Stefan Larsson, Navpreet Kaur, R. Desiante, L. O. Takalo, I. Reichardt, Francesco Longo, E. Prandini, Arka Chatterjee, A. Sillanpää, M. Peresano, A. Niedzwiecki, D. Hadasch, Elina Lindfors, D. Fidalgo, M. Engelkemeier, C. Protasio, S. Bonnefoy, Iain A. Steele, Daniel Mazin, S. Paiano, Karl Mannheim, Takashi Saito, Nicholas R. MacDonald, David Paneque, D. Guberman, Anne Lähteenmäki, Svetlana G. Jorstad, Kiran S. Baliyan, Tarek M. Hassan, W. Bednarek, L. Perri, Fabrizio Tavecchio, U. Menzel, Masahiro Teshima, M. Palatiello, Marina Manganaro, Stefano Ansoldi, Yusuke Konno, Ll. Font, Merja Tornikoski, S. Schroeder, Ivica Puljak, Riccardo Paoletti, D. Eisenacher Glawion, F. Di Pierro, Pierre Colin, Oscar Blanch, Pratik Majumdar, Mosè Mariotti, Markus Garczarczyk, Francesco Dazzi, M. Nievas Rosillo, T. S. Grishina, Louis Antonelli, M. V. Fonseca, A. Fernández-Barral, J. Hose, Max Ludwig Ahnen, F. Borracci, Emilia Järvelä, R. J. García López, G. Pedaletti, Thomas Bretz, Stefano Covino, P. Cumani, Kazuma Ishio, C. M. Raiteri, Konstancja Satalecka, T. Surić, M. Doert, M. H. Wu, E. de Oña Wilhelmi, D. Elsaesser, Michele Doro, A. B. Grinon-Marin, Dario Hrupec, J. Becerra González, D. Kuveždić, Nikola Godinovic, P. Temnikov, C. Lázaro, Saverio Lombardi, A. Pastor Yabar, Helen Jermak, Rodolfo Carosi, M. A. Lopez, Antonio Stamerra, J. E. Ward, S. N. Shore, Alessio Berti, P. Giammaria, Filippo D'Ammando, Juan Abel Barrio, R. Reinthal, P. Da Vela, D. Tescaro, P. G. Prada Moroni, Razmik Mirzoyan, U. Barres de Almeida, Massimo Persic, Alessandro Carosi, D. Galindo, Aaron Dominguez, L. Maraschi, Damir Lelas, Kari Nilsson, Daniela Dorner, Dariusz Gora, Gaia Vanzo, N. Torres-Albà, E. Moretti, M. Hayashida, Sameer, M. Gaug, Dorota Sobczyńska, J. M. Paredes, X. Paredes-Fortuny, J. Herrera, C. Martínez-Lombilla, D. Zarić, M. Will, Alexander Hahn, Tomislav Terzić, Koji Noda, Marc Ribó, Elisa Bernardini, J. R. Garcia, Gareth Hughes, Hidetoshi Kubo, K. Nishijima, D. Dominis Prester, V. Ramakrishnan, V. Fallah Ramazani, M. I. Martínez, G. A. Borman, Wolfgang Rhode, P. Bangale, J. Kushida, Jose Luis Contreras, Sabrina Einecke, G. Bonnoli, Juan Cortina, B. Banerjee, C. Arcaro, Valeri M. Larionov, Ana Babić, Adrian Biland, J. Rico, M. I. Carnerero, Alan P. Marscher, Ievgen Vovk, A. De Angelis, A. Treves, Vitaly Neustroev, T. Schweizer, G. Maneva, Juri Poutanen, Ahnen, M. L., Ansoldi, S., Antonelli, L. A., Arcaro, C., Babiä , A., Banerjee, B., Bangale, P., Barres De Almeida, U., Barrio, J. A., Bednarek, W., Bernardini, E., Berti, Alessio, Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carosi, R., Carosi, A., Chatterjee, A., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Cumani, P., Da Vela, P., Dazzi, F., De Angelis, A., De Lotto, B., De Oña Wilhelmi, E., Di Pierro, F., Doert, M., Domã­nguez, A., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher Glawion, D., Elsaesser, D., Engelkemeier, M., Fallah Ramazani, V., Fernández Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Gaug, M., Giammaria, P., Godinoviä , N., Gora, D., Guberman, D., Hadasch, D., Hahn, A., Hassan, T., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Hughes, G., Ishio, K., Konno, Y., Kubo, H., Kushida, J., Kuveå¾diä , D., Lelas, D., Lindfors, E., Lombardi, S., Longo, Francesco, Lã³pez, M., Majumdar, P., Makariev, M., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Mariotti, M., Martã­nez, M., Mazin, D., Menzel, U., Mirzoyan, R., Moralejo, A., Moretti, E., Nakajima, D., Neustroev, V., Niedzwiecki, A., Nievas Rosillo, M., Nilsson, K., Nishijima, K., Noda, K., Noguã©s, L., Paiano, S., Palacio, J., Palatiello, Michele, Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Pedaletti, G., Peresano, M., Perri, L., Persic, M., Poutanen, J., Prada Moroni, P. G., Prandini, E., Puljak, I., Garcia, J. R., Reichardt, I., Rhode, W., Ribã³, M., Rico, J., Saito, T., Satalecka, K., Schroeder, S., Schweizer, T., Shore, S. N., Sillanpã¤ã¤, A., Sitarek, J, Å nidariä , I., Sobczynska, D., Stamerra, A., Strzys, M., Suriä , T., Takalo, L., Tavecchio, F., Temnikov, P., Terziä , T., Tescaro, D., Teshima, M., Torres, D. F., Torres Albà , N., Toyama, T., Treves, A., Vanzo, G., Vazquez Acosta, M., Vovk, I., Ward, J. E., Will, M., Wu, M. H., Zariä , D., Desiante, R., Becerra González, J., D'Ammando, F., Larsson, S., Raiteri, C. M., Reinthal, R., Lã¤hteenmã¤ki, A., Jã¤rvelã¤, E., Tornikoski, M., Ramakrishnan, V., Jorstad, S. G., Marscher, A. P., Bala, V., Macdonald, N. R., Kaur, N., Sameer, Null, Baliyan, K., Acosta Pulido, J. A., Lazaro, C., Martí Nez Lombilla, C., Grinon Marin, A. B., Pastor Yabar, A., Protasio, C., Carnerero, M. I., Jermak, H., Steele, I. A., Larionov, V. M., Borman, G. A., Grishina, T. S., Swiss Federal Institute of Technology Zurich, University of Udine, INAF National Institute for Astrophysics, University of Padova, University of Rijeka, Saha Institute of Nuclear Physics, Max Planck Institute for Physics, Complutense University, University of Łódź, German Electron Synchrotron, Autonomous University of Barcelona, University of Siena, University of Würzburg, Instituto de Astrofísica de Canarias, Institute of Space Studies of Catalonia, Dortmund University, Finnish MAGIC Consortium, University of Barcelona, The University of Tokyo, Osservatorio Astronomicodi Roma, Bulgarian Academy of Sciences, University of Pisa, University of Bologna, KTH Royal Institute of Technology, University of Turku, Metsähovi Radio Observatory, Department of Radio Science and Engineering, Boston University, Physical Research Laboratory India, Lancaster University, Liverpool John Moores University, St. Petersburg State University, Crimean Astrophysical Observatory, Department of Electronics and Nanoengineering, Aalto-yliopisto, and Aalto University

Subjects
galaxies [Gamma rays], VHE [gamma ray], Astrophysics, 01 natural sciences, rotation, jet [Galaxies], law.invention, law, galaxies, active, galaxies: jets, gamma rays: galaxies, quasars: individual: PKS 1510-089, Broadband, QD, 010303 astronomy & astrophysics, QC, QB, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), galaxie [Gamma rays], Gamma ray, Optical polarization, Galaxies: active, Polarization (waves), Gamma rays: galaxies, optical [polarization], Spectral energy distribution, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, Galaxies: jets, Quasars: individual: PKS 1510-089, Astronomy and Astrophysics, Space and Planetary Science, Flare, active [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Photometry (optics), X-ray, 0103 physical sciences, individual: PKS 1510-089 [Quasars], quasar, Astrophysics::Galaxy Astrophysics, 010308 nuclear & particles physics, Quasar, Astronomy and Astrophysic, MAGIC, flux, ddc:520, spectral, jets [Galaxies]
Abstract

Context. PKS 1510-089 is one of only a few flat spectrum radio quasars detected in the VHE (very-high-energy, > 100 GeV) gamma-ray band. Aims. We study the broadband spectral and temporal properties of the PKS 1510-089 emission during a high gamma-ray state. Methods. We performed VHE gamma-ray observations of PKS 1510-089 with the MAGIC telescopes during a long high gamma-ray state in May 2015. In order to perform broadband modelling of the source, we have also gathered contemporaneous multiwavelength data in radio, IR, optical photometry and polarization, UV, X-ray and GeV gamma-ray ranges. We construct a broadband spectral energy distribution (SED) in two periods, selected according to VHE gamma-ray state. Results. PKS 1510-089 has been detected by MAGIC during a few day-long observations performed in the middle of a long, high optical and gamma-ray state, showing for the first time a significant VHE gamma-ray variability. Similarly to the optical and gamma-ray high state of the source detected in 2012, it was accompanied by a rotation of the optical polarization angle and the emission of a new jet component observed in radio. However, due to large uncertainty on the knot separation time, the association with the VHE gamma-ray emission cannot be firmly established. The spectral shape in the VHE band during the flare is similar to the ones obtained during previous measurements of the source. The observed flux variability sets for the first time constraints on the size of the region from which VHE gamma rays are emitted. We model the broadband SED in the framework of the external Compton scenario and discuss the possible emission site in view of multiwavelength data and alternative emission models., 12 pages, 10 figures, accepted for a publication in A&A

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157. The Bright γ-ray Flare of 3C 279 in 2015 June: AGILE Detection and Multifrequency Follow-up Observations.

Author

C. Pittori, F. Lucarelli, F. Verrecchia, C. M. Raiteri, M. Villata, V. Vittorini, M. Tavani, S. Puccetti, M. Perri, I. Donnarumma, S. Vercellone, J. A. Acosta-Pulido, R. Bachev, E. Benítez, G. A. Borman, M. I. Carnerero, D. Carosati, W. P. Chen, Sh. A. Ehgamberdiev, and A. Goded

Subjects
ACTIVE galaxies, GAMMA rays, QUASARS, ASTROPHYSICAL radiation, X-ray polarization
Abstract

We report the AGILE detection and the results of the multifrequency follow-up observations of a bright γ-ray flare of the blazar 3C 279 in 2015 June. We use AGILE and Fermi gamma-ray data, together with Swift X-ray andoptical-ultraviolet data, and ground-based GASP-WEBT optical observations, including polarization information, to study the source variability and the overall spectral energy distribution during the γ-ray flare. The γ-ray flaring data, compared with as yet unpublished simultaneous optical data that will allow constraints on the big blue bump disk luminosity, show very high Compton dominance values of ∼100, with the ratio of γ-ray to optical emission rising by a factor of three in a few hours. The multiwavelength behavior of the source during the flare challenges one-zone leptonic theoretical models. The new observations during the 2015 June flare are also compared with already published data and nonsimultaneous historical 3C 279 archival data. [ABSTRACT FROM AUTHOR]

Published
2018
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158. An UXor among FUors: Extinction-related Brightness Variations of the Young Eruptive Star V582 Aur.

Author

P. Ábrahám, Á. Kóspál, M. Kun, O. Fehér, G. Zsidi, J. A. Acosta-Pulido, M. I. Carnerero, D. García-Álvarez, A. Moór, B. Cseh, G. Hajdu, O. Hanyecz, J. Kelemen, L. Kriskovics, G. Marton, Gy. Mező, L. Molnár, A. Ordasi, G. Rodríguez-Coira, and K. Sárneczky

Subjects
ASTRONOMICAL photometry, STELLAR mass, MOLECULAR clouds, ASTRONOMICAL constants, MILLIMETER waves
Abstract

V582 Aur is an FU Ori-type young eruptive star in outburst since ∼1985. The eruption is currently in a relatively constant plateau phase, with photometric and spectroscopic variability superimposed. Here we will characterize the progenitor of the outbursting object, explore its environment, and analyze the temporal evolution of the eruption. We are particularly interested in the physical origin of the two deep photometric dips, one that occurred in 2012 and one that is ongoing since 2016. We collected archival photographic plates and carried out new optical, infrared, and millimeter-wave photometric and spectroscopic observations between 2010 and 2018, with a high sampling rate during the current minimum. Besides analyzing the color changes during fading, we compiled multiepoch spectral energy distributions and fitted them with a simple accretion disk model. Based on pre-outburst data and a millimeter continuum measurement, we suggest that the progenitor of the V582 Aur outburst is a low-mass T Tauri star with average properties. The mass of an unresolved circumstellar structure, probably a disk, is 0.04 M⊙. The optical and near-infrared spectra demonstrate the presence of hydrogen and metallic lines, show the CO band head in absorption, and exhibit a variable Hα profile. The color variations strongly indicate that both the ∼1 yr long brightness dip in 2012 and the current minimum since 2016 are caused by increased extinction along the line of sight. According to our accretion disk models, the reddening changed from AV = 4.5 to 12.5 mag, while the accretion rate remained practically constant. Similarly to the models of the UXor phenomenon of intermediate- and low-mass young stars, orbiting disk structures could be responsible for the eclipses. [ABSTRACT FROM AUTHOR]

Published
2018
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