Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009

M. L. Ahnen, S. Ansoldi, L. A. Antonelli, P. Antoranz, A. Babic, B. Banerjee, P. Bangale, U. Barres De Almeida, J. A. Barrio, J. Becerra González, W. Bednarek, E. Bernardini, A. Berti, B. Biasuzzi, A. Biland, O. Blanch, S. Bonnefoy, G. Bonnoli, F. Borracci, T. BretzS. Buson, A. Carosi, A. Chatterjee, R. Clavero, P. Colin, E. Colombo, J. L. Contreras, J. Cortina, S. Covino, P. Da Vela, F. Dazzi, A. De Angelis, B. De Lotto, E. De Oña Wilhelmi, F. Di Pierro, M. Doert, A. Domínguez, D. Dominis Prester, D. Dorner, M. Doro, S. Einecke, D. Eisenacher Glawion, D. Elsaesser, M. Engelkemeier, V. Fallah Ramazani, A. Fernández-Barral, D. Fidalgo, M. V. Fonseca, L. Font, K. Frantzen, C. Fruck, D. Galindo, R. J. García López, M. Garczarczyk, D. Garrido Terrats, M. Gaug, P. Giammaria, N. Godinović, A. González Muñoz, D. Gora, D. Guberman, D. Hadasch, A. Hahn, Y. Hanabata, M. Hayashida, J. Herrera, J. Hose, D. Hrupec, G. Hughes, W. Idec, K. Kodani, Y. Konno, H. Kubo, J. Kushida, A. La Barbera, D. Lelas, E. Lindfors, S. Lombardi, F. Longo, M. López, R. López-Coto, P. Majumdar, M. Makariev, K. Mallot, G. Maneva, M. Manganaro, K. Mannheim, L. Maraschi, B. Marcote, M. Mariotti, M. Martínez, D. Mazin, U. Menzel, J. M. Miranda, R. Mirzoyan, A. Moralejo, E. Moretti, D. Nakajima, V. Neustroev, A. Niedzwiecki, M. Nievas Rosillo, K. Nilsson, K. Nishijima, K. Noda, L. Nogués, A. Overkemping, S. Paiano, J. Palacio, M. Palatiello, D. Paneque, R. Paoletti, J. M. Paredes, X. Paredes-Fortuny, G. Pedaletti, M. Peresano, L. Perri, M. Persic, J. Poutanen, P. G. Prada Moroni, E. Prandini, I. Puljak, I. Reichardt, W. Rhode, M. Ribó, J. Rico, J. Rodriguez Garcia, T. Saito, K. Satalecka, S. Schröder, C. Schultz, T. Schweizer, S. N. Shore, A. Sillanpää, J. Sitarek, I. Snidaric, D. Sobczynska, A. Stamerra, T. Steinbring, M. Strzys, T. Surić, L. Takalo, F. Tavecchio, P. Temnikov, T. Terzić, D. Tescaro, M. Teshima, J. Thaele, D. F. Torres, T. Toyama, A. Treves, G. Vanzo, V. Verguilov, I. Vovk, J. E. Ward, M. Will, M. H. Wu, R. Zanin, A. U. Abeysekara, S. Archambault, A. Archer, W. Benbow, R. Bird, M. Buchovecky, J. H. Buckley, V. Bugaev, M. P. Connolly, W. Cui, H. J. Dickinson, A. Falcone, Q. Feng, J. P. Finley, H. Fleischhack, A. Flinders, L. Fortson, G. H. Gillanders, S. Griffin, J. Grube, M. Hütten, D. Hanna, J. Holder, T. B. Humensky, P. Kaaret, P. Kar, N. Kelley-Hoskins, M. Kertzman, D. Kieda, M. Krause, F. Krennrich, M. J. Lang, G. Maier, A. McCann, P. Moriarty, R. Mukherjee, D. Nieto, S. O'Brien, R. A. Ong, N. Otte, N. Park, J. Perkins, A. Pichel, M. Pohl, A. Popkow, E. Pueschel, J. Quinn, K. Ragan, P. T. Reynolds, G. T. Richards, E. Roache, A. C. Rovero, C. Rulten, I. Sadeh, M. Santander, G. H. Sembroski, K. Shahinyan, I. Telezhinsky, J. V. Tucci, J. Tyler, S. P. Wakely, A. Weinstein, P. Wilcox, A. Wilhelm, D. A. Williams, B. Zitzer, S. Razzaque, M. Villata, C. M. Raiteri, H. D. Aller, M. F. Aller, V. M. Larionov, A. A. Arkharov, D. A. Blinov, N. V. Efimova, T. S. Grishina, V. A. Hagen-Thorn, E. N. Kopatskaya, L. V. Larionova, E. G. Larionova, D. A. Morozova, I. S. Troitsky, R. Ligustri, P. Calcidese, A. Berdyugin, O. M. Kurtanidze, M. G. Nikolashvili, G. N. Kimeridze, L. A. Sigua, S. O. Kurtanidze, R. A. Chigladze, W. P. Chen, E. Koptelova, T. Sakamoto, A. C. Sadun, J. W. Moody, C. Pace, R. Pearson, Y. Yatsu, Y. Mori, A. Carraminyana, L. Carrasco, E. De La Fuente, J. P. Norris, P. S. Smith, A. Wehrle, M. A. Gurwell, A. Zook, C. Pagani, M. Perri, M. Capalbi, A. Cesarini, H. A. Krimm, Y. Y. Kovalev, Yu A. Kovalev, E. Ros, A. B. Pushkarev, M. L. Lister, K. V. Sokolovsky, M. Kadler, G. Piner, A. Lähteenmäki, M. Tornikoski, E. Angelakis, T. P. Krichbaum, I. Nestoras, L. Fuhrmann, J. A. Zensus, P. Cassaro, A. Orlati, G. MacCaferri, P. Leto, M. Giroletti, J. L. Richards, W. Max-Moerbeck, A. C.S. Readhead

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Context. We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1, which includes, among other instruments, MAGIC, VERITAS, Whipple 10 m, and Fermi-LAT to cover the γ-ray range from 0.1 GeV to 20 TeV; RXTE and Swift to cover wavelengths from UV tohard X-rays; and GASP-WEBT, which provides coverage of radio and optical wavelengths. Optical polarization measurements were provided for a fraction of the campaign by the Steward and St. Petersburg observatories. We evaluate the variability of the source and interband correlations, the γ-ray flaring activity occurring in May 2009, and interpret the results within two synchrotron self-Compton (SSC) scenarios. Aims. The multiband variability observed during the full campaign is addressed in terms of the fractional variability, and the possible correlations are studied by calculating the discrete correlation function for each pair of energy bands where the significance was evaluated with dedicated Monte Carlo simulations. The space of SSC model parameters is probed following a dedicated grid-scan strategy, allowing for a wide range of models to be tested and offering a study of the degeneracy of model-to-data agreement in the individual model parameters, hence providing a less biased interpretation than the "single-curve SSC model adjustment" typically reported in the literature. Methods. We find an increase in the fractional variability with energy, while no significant interband correlations of flux changes are found on the basis of the acquired data set. The SSC model grid-scan shows that the flaring activity around May 22 cannot be modeled adequately with a one-zone SSC scenario (using an electron energy distribution with two breaks), while it can be suitably described within a two (independent) zone SSC scenario. Here, one zone is responsible for the quiescent emission from the averaged 4.5-month observing period, while the other one, which is spatially separated from the first, dominates the flaring emission occurring at X-rays and very-high-energy (>100 GeV, VHE) γ rays. The flaring activity from May 1, which coincides with a rotation of the electric vector polarization angle (EVPA), cannot be satisfactorily reproduced by either a one-zone or a two-independent-zone SSC model, yet this is partially affected by the lack of strictly simultaneous observations and the presence of large flux changes on sub-hour timescales (detected at VHE γ rays). Results. The higher variability in the VHE emission and lack of correlation with the X-ray emission indicate that, at least during the 4.5-month observing campaign in 2009, the highest energy (and most variable) electrons that are responsible for the VHE γ rays do not make a dominant contribution to the ~1 keV emission. Alternatively, there could be a very variable component contributing to the VHE γ-ray emission in addition to that coming from the SSC scenario. The studies with our dedicated SSC grid-scan show that there is some degeneracy in both the one-zone and the two-zone SSC scenarios probed, with several combinations of model parameters yielding a similar model-to-data agreement, and some parameters better constrained than others. The observed γ-ray flaring activity, with the EVPA rotation coincident with the first γ-ray flare, resembles those reported previously for low frequency peaked blazars, hence suggesting that there are many similarities in the flaring mechanisms of blazars with different jet properties.

Original languageEnglish (US)
Article numberA31
JournalAstronomy and Astrophysics
Volume603
DOIs
StatePublished - Jul 1 2017

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synchrotrons
broadband
rays
modeling
polarization
energy
blazars
grids
wavelength
Global Air Sampling Program
electron
x rays
optical polarization
X Ray Timing Explorer
flaring
wavelengths
flares
energy bands
observatory
observatories

Keywords

  • BL Lacertae objects: individual: Markarian 501
  • Methods: data analysis

Cite this

Ahnen, M. L., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Banerjee, B., ... Readhead, A. C. S. (2017). Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009. Astronomy and Astrophysics, 603, [A31]. https://doi.org/10.1051/0004-6361/201629540

Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009. / Ahnen, M. L.; Ansoldi, S.; Antonelli, L. A.; Antoranz, P.; Babic, A.; Banerjee, B.; Bangale, P.; Barres De Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Berti, A.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Borracci, F.; Bretz, T.; Buson, S.; Carosi, A.; Chatterjee, A.; Clavero, R.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Lotto, B.; De Oña Wilhelmi, E.; Di Pierro, F.; Doert, M.; Domínguez, 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.; Frantzen, K.; Fruck, C.; Galindo, D.; García López, R. J.; Garczarczyk, M.; Garrido Terrats, D.; Gaug, M.; Giammaria, P.; Godinović, N.; González Muñoz, A.; Gora, D.; Guberman, D.; Hadasch, D.; Hahn, A.; Hanabata, Y.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Hughes, G.; Idec, W.; Kodani, K.; Konno, Y.; Kubo, H.; Kushida, J.; La Barbera, A.; Lelas, D.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; López-Coto, R.; Majumdar, P.; Makariev, M.; Mallot, K.; Maneva, G.; Manganaro, M.; Mannheim, K.; Maraschi, L.; Marcote, B.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Miranda, J. M.; Mirzoyan, R.; Moralejo, A.; Moretti, E.; Nakajima, D.; Neustroev, V.; Niedzwiecki, A.; Nievas Rosillo, M.; Nilsson, K.; Nishijima, K.; Noda, K.; Nogués, L.; Overkemping, A.; Paiano, S.; Palacio, J.; Palatiello, M.; 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.; Reichardt, I.; Rhode, W.; Ribó, M.; Rico, J.; Rodriguez Garcia, J.; Saito, T.; Satalecka, K.; Schröder, S.; Schultz, C.; Schweizer, T.; Shore, S. N.; Sillanpää, A.; Sitarek, J.; Snidaric, I.; Sobczynska, D.; Stamerra, A.; Steinbring, T.; Strzys, M.; Surić, T.; Takalo, L.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Tescaro, D.; Teshima, M.; Thaele, J.; Torres, D. F.; Toyama, T.; Treves, A.; Vanzo, G.; Verguilov, V.; Vovk, I.; Ward, J. E.; Will, M.; Wu, M. H.; Zanin, R.; Abeysekara, A. U.; Archambault, S.; Archer, A.; Benbow, W.; Bird, R.; Buchovecky, M.; Buckley, J. H.; Bugaev, V.; Connolly, M. P.; Cui, W.; Dickinson, H. J.; Falcone, A.; Feng, Q.; Finley, J. P.; Fleischhack, H.; Flinders, A.; Fortson, L.; Gillanders, G. H.; Griffin, S.; Grube, J.; Hütten, M.; Hanna, D.; Holder, J.; Humensky, T. B.; Kaaret, P.; Kar, P.; Kelley-Hoskins, N.; Kertzman, M.; Kieda, D.; Krause, M.; Krennrich, F.; Lang, M. J.; Maier, G.; McCann, A.; Moriarty, P.; Mukherjee, R.; Nieto, D.; O'Brien, S.; Ong, R. A.; Otte, N.; Park, N.; Perkins, J.; Pichel, A.; Pohl, M.; Popkow, A.; Pueschel, E.; Quinn, J.; Ragan, K.; Reynolds, P. T.; Richards, G. T.; Roache, E.; Rovero, A. C.; Rulten, C.; Sadeh, I.; Santander, M.; Sembroski, G. H.; Shahinyan, K.; Telezhinsky, I.; Tucci, J. V.; Tyler, J.; Wakely, S. P.; Weinstein, A.; Wilcox, P.; Wilhelm, A.; Williams, D. A.; Zitzer, B.; Razzaque, S.; Villata, M.; Raiteri, C. M.; Aller, H. D.; Aller, M. F.; Larionov, V. M.; Arkharov, A. A.; Blinov, D. A.; Efimova, N. V.; Grishina, T. S.; Hagen-Thorn, V. A.; Kopatskaya, E. N.; Larionova, L. V.; Larionova, E. G.; Morozova, D. A.; Troitsky, I. S.; Ligustri, R.; Calcidese, P.; Berdyugin, A.; Kurtanidze, O. M.; Nikolashvili, M. G.; Kimeridze, G. N.; Sigua, L. A.; Kurtanidze, S. O.; Chigladze, R. A.; Chen, W. P.; Koptelova, E.; Sakamoto, T.; Sadun, A. C.; Moody, J. W.; Pace, C.; Pearson, R.; Yatsu, Y.; Mori, Y.; Carraminyana, A.; Carrasco, L.; De La Fuente, E.; Norris, J. P.; Smith, P. S.; Wehrle, A.; Gurwell, M. A.; Zook, A.; Pagani, C.; Perri, M.; Capalbi, M.; Cesarini, A.; Krimm, H. A.; Kovalev, Y. Y.; Kovalev, Yu A.; Ros, E.; Pushkarev, A. B.; Lister, M. L.; Sokolovsky, K. V.; Kadler, M.; Piner, G.; Lähteenmäki, A.; Tornikoski, M.; Angelakis, E.; Krichbaum, T. P.; Nestoras, I.; Fuhrmann, L.; Zensus, J. A.; Cassaro, P.; Orlati, A.; MacCaferri, G.; Leto, P.; Giroletti, M.; Richards, J. L.; Max-Moerbeck, W.; Readhead, A. C.S.

In: Astronomy and Astrophysics, Vol. 603, A31, 01.07.2017.

Research output: Contribution to journalArticle

Ahnen, ML, Ansoldi, S, Antonelli, LA, Antoranz, P, Babic, A, Banerjee, B, Bangale, P, Barres De Almeida, U, Barrio, JA, Becerra González, J, Bednarek, W, Bernardini, E, Berti, A, Biasuzzi, B, Biland, A, Blanch, O, Bonnefoy, S, Bonnoli, G, Borracci, F, Bretz, T, Buson, S, Carosi, A, Chatterjee, A, Clavero, R, Colin, P, Colombo, E, Contreras, JL, Cortina, J, Covino, S, Da Vela, P, Dazzi, F, De Angelis, A, De Lotto, B, De Oña Wilhelmi, E, Di Pierro, F, Doert, M, Domínguez, 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, MV, Font, L, Frantzen, K, Fruck, C, Galindo, D, García López, RJ, Garczarczyk, M, Garrido Terrats, D, Gaug, M, Giammaria, P, Godinović, N, González Muñoz, A, Gora, D, Guberman, D, Hadasch, D, Hahn, A, Hanabata, Y, Hayashida, M, Herrera, J, Hose, J, Hrupec, D, Hughes, G, Idec, W, Kodani, K, Konno, Y, Kubo, H, Kushida, J, La Barbera, A, Lelas, D, Lindfors, E, Lombardi, S, Longo, F, López, M, López-Coto, R, Majumdar, P, Makariev, M, Mallot, K, Maneva, G, Manganaro, M, Mannheim, K, Maraschi, L, Marcote, B, Mariotti, M, Martínez, M, Mazin, D, Menzel, U, Miranda, JM, Mirzoyan, R, Moralejo, A, Moretti, E, Nakajima, D, Neustroev, V, Niedzwiecki, A, Nievas Rosillo, M, Nilsson, K, Nishijima, K, Noda, K, Nogués, L, Overkemping, A, Paiano, S, Palacio, J, Palatiello, M, Paneque, D, Paoletti, R, Paredes, JM, Paredes-Fortuny, X, Pedaletti, G, Peresano, M, Perri, L, Persic, M, Poutanen, J, Prada Moroni, PG, Prandini, E, Puljak, I, Reichardt, I, Rhode, W, Ribó, M, Rico, J, Rodriguez Garcia, J, Saito, T, Satalecka, K, Schröder, S, Schultz, C, Schweizer, T, Shore, SN, Sillanpää, A, Sitarek, J, Snidaric, I, Sobczynska, D, Stamerra, A, Steinbring, T, Strzys, M, Surić, T, Takalo, L, Tavecchio, F, Temnikov, P, Terzić, T, Tescaro, D, Teshima, M, Thaele, J, Torres, DF, Toyama, T, Treves, A, Vanzo, G, Verguilov, V, Vovk, I, Ward, JE, Will, M, Wu, MH, Zanin, R, Abeysekara, AU, Archambault, S, Archer, A, Benbow, W, Bird, R, Buchovecky, M, Buckley, JH, Bugaev, V, Connolly, MP, Cui, W, Dickinson, HJ, Falcone, A, Feng, Q, Finley, JP, Fleischhack, H, Flinders, A, Fortson, L, Gillanders, GH, Griffin, S, Grube, J, Hütten, M, Hanna, D, Holder, J, Humensky, TB, Kaaret, P, Kar, P, Kelley-Hoskins, N, Kertzman, M, Kieda, D, Krause, M, Krennrich, F, Lang, MJ, Maier, G, McCann, A, Moriarty, P, Mukherjee, R, Nieto, D, O'Brien, S, Ong, RA, Otte, N, Park, N, Perkins, J, Pichel, A, Pohl, M, Popkow, A, Pueschel, E, Quinn, J, Ragan, K, Reynolds, PT, Richards, GT, Roache, E, Rovero, AC, Rulten, C, Sadeh, I, Santander, M, Sembroski, GH, Shahinyan, K, Telezhinsky, I, Tucci, JV, Tyler, J, Wakely, SP, Weinstein, A, Wilcox, P, Wilhelm, A, Williams, DA, Zitzer, B, Razzaque, S, Villata, M, Raiteri, CM, Aller, HD, Aller, MF, Larionov, VM, Arkharov, AA, Blinov, DA, Efimova, NV, Grishina, TS, Hagen-Thorn, VA, Kopatskaya, EN, Larionova, LV, Larionova, EG, Morozova, DA, Troitsky, IS, Ligustri, R, Calcidese, P, Berdyugin, A, Kurtanidze, OM, Nikolashvili, MG, Kimeridze, GN, Sigua, LA, Kurtanidze, SO, Chigladze, RA, Chen, WP, Koptelova, E, Sakamoto, T, Sadun, AC, Moody, JW, Pace, C, Pearson, R, Yatsu, Y, Mori, Y, Carraminyana, A, Carrasco, L, De La Fuente, E, Norris, JP, Smith, PS, Wehrle, A, Gurwell, MA, Zook, A, Pagani, C, Perri, M, Capalbi, M, Cesarini, A, Krimm, HA, Kovalev, YY, Kovalev, YA, Ros, E, Pushkarev, AB, Lister, ML, Sokolovsky, KV, Kadler, M, Piner, G, Lähteenmäki, A, Tornikoski, M, Angelakis, E, Krichbaum, TP, Nestoras, I, Fuhrmann, L, Zensus, JA, Cassaro, P, Orlati, A, MacCaferri, G, Leto, P, Giroletti, M, Richards, JL, Max-Moerbeck, W & Readhead, ACS 2017, 'Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009', Astronomy and Astrophysics, vol. 603, A31. https://doi.org/10.1051/0004-6361/201629540
Ahnen, M. L. ; Ansoldi, S. ; Antonelli, L. A. ; Antoranz, P. ; Babic, A. ; Banerjee, B. ; Bangale, P. ; Barres De Almeida, U. ; Barrio, J. A. ; Becerra González, J. ; Bednarek, W. ; Bernardini, E. ; Berti, A. ; Biasuzzi, B. ; Biland, A. ; Blanch, O. ; Bonnefoy, S. ; Bonnoli, G. ; Borracci, F. ; Bretz, T. ; Buson, S. ; Carosi, A. ; Chatterjee, A. ; Clavero, R. ; Colin, P. ; Colombo, E. ; Contreras, J. L. ; Cortina, J. ; Covino, S. ; Da Vela, P. ; Dazzi, F. ; De Angelis, A. ; De Lotto, B. ; De Oña Wilhelmi, E. ; Di Pierro, F. ; Doert, M. ; Domínguez, 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. ; Frantzen, K. ; Fruck, C. ; Galindo, D. ; García López, R. J. ; Garczarczyk, M. ; Garrido Terrats, D. ; Gaug, M. ; Giammaria, P. ; Godinović, N. ; González Muñoz, A. ; Gora, D. ; Guberman, D. ; Hadasch, D. ; Hahn, A. ; Hanabata, Y. ; Hayashida, M. ; Herrera, J. ; Hose, J. ; Hrupec, D. ; Hughes, G. ; Idec, W. ; Kodani, K. ; Konno, Y. ; Kubo, H. ; Kushida, J. ; La Barbera, A. ; Lelas, D. ; Lindfors, E. ; Lombardi, S. ; Longo, F. ; López, M. ; López-Coto, R. ; Majumdar, P. ; Makariev, M. ; Mallot, K. ; Maneva, G. ; Manganaro, M. ; Mannheim, K. ; Maraschi, L. ; Marcote, B. ; Mariotti, M. ; Martínez, M. ; Mazin, D. ; Menzel, U. ; Miranda, J. M. ; Mirzoyan, R. ; Moralejo, A. ; Moretti, E. ; Nakajima, D. ; Neustroev, V. ; Niedzwiecki, A. ; Nievas Rosillo, M. ; Nilsson, K. ; Nishijima, K. ; Noda, K. ; Nogués, L. ; Overkemping, A. ; Paiano, S. ; Palacio, J. ; Palatiello, M. ; 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. ; Reichardt, I. ; Rhode, W. ; Ribó, M. ; Rico, J. ; Rodriguez Garcia, J. ; Saito, T. ; Satalecka, K. ; Schröder, S. ; Schultz, C. ; Schweizer, T. ; Shore, S. N. ; Sillanpää, A. ; Sitarek, J. ; Snidaric, I. ; Sobczynska, D. ; Stamerra, A. ; Steinbring, T. ; Strzys, M. ; Surić, T. ; Takalo, L. ; Tavecchio, F. ; Temnikov, P. ; Terzić, T. ; Tescaro, D. ; Teshima, M. ; Thaele, J. ; Torres, D. F. ; Toyama, T. ; Treves, A. ; Vanzo, G. ; Verguilov, V. ; Vovk, I. ; Ward, J. E. ; Will, M. ; Wu, M. H. ; Zanin, R. ; Abeysekara, A. U. ; Archambault, S. ; Archer, A. ; Benbow, W. ; Bird, R. ; Buchovecky, M. ; Buckley, J. H. ; Bugaev, V. ; Connolly, M. P. ; Cui, W. ; Dickinson, H. J. ; Falcone, A. ; Feng, Q. ; Finley, J. P. ; Fleischhack, H. ; Flinders, A. ; Fortson, L. ; Gillanders, G. H. ; Griffin, S. ; Grube, J. ; Hütten, M. ; Hanna, D. ; Holder, J. ; Humensky, T. B. ; Kaaret, P. ; Kar, P. ; Kelley-Hoskins, N. ; Kertzman, M. ; Kieda, D. ; Krause, M. ; Krennrich, F. ; Lang, M. J. ; Maier, G. ; McCann, A. ; Moriarty, P. ; Mukherjee, R. ; Nieto, D. ; O'Brien, S. ; Ong, R. A. ; Otte, N. ; Park, N. ; Perkins, J. ; Pichel, A. ; Pohl, M. ; Popkow, A. ; Pueschel, E. ; Quinn, J. ; Ragan, K. ; Reynolds, P. T. ; Richards, G. T. ; Roache, E. ; Rovero, A. C. ; Rulten, C. ; Sadeh, I. ; Santander, M. ; Sembroski, G. H. ; Shahinyan, K. ; Telezhinsky, I. ; Tucci, J. V. ; Tyler, J. ; Wakely, S. P. ; Weinstein, A. ; Wilcox, P. ; Wilhelm, A. ; Williams, D. A. ; Zitzer, B. ; Razzaque, S. ; Villata, M. ; Raiteri, C. M. ; Aller, H. D. ; Aller, M. F. ; Larionov, V. M. ; Arkharov, A. A. ; Blinov, D. A. ; Efimova, N. V. ; Grishina, T. S. ; Hagen-Thorn, V. A. ; Kopatskaya, E. N. ; Larionova, L. V. ; Larionova, E. G. ; Morozova, D. A. ; Troitsky, I. S. ; Ligustri, R. ; Calcidese, P. ; Berdyugin, A. ; Kurtanidze, O. M. ; Nikolashvili, M. G. ; Kimeridze, G. N. ; Sigua, L. A. ; Kurtanidze, S. O. ; Chigladze, R. A. ; Chen, W. P. ; Koptelova, E. ; Sakamoto, T. ; Sadun, A. C. ; Moody, J. W. ; Pace, C. ; Pearson, R. ; Yatsu, Y. ; Mori, Y. ; Carraminyana, A. ; Carrasco, L. ; De La Fuente, E. ; Norris, J. P. ; Smith, P. S. ; Wehrle, A. ; Gurwell, M. A. ; Zook, A. ; Pagani, C. ; Perri, M. ; Capalbi, M. ; Cesarini, A. ; Krimm, H. A. ; Kovalev, Y. Y. ; Kovalev, Yu A. ; Ros, E. ; Pushkarev, A. B. ; Lister, M. L. ; Sokolovsky, K. V. ; Kadler, M. ; Piner, G. ; Lähteenmäki, A. ; Tornikoski, M. ; Angelakis, E. ; Krichbaum, T. P. ; Nestoras, I. ; Fuhrmann, L. ; Zensus, J. A. ; Cassaro, P. ; Orlati, A. ; MacCaferri, G. ; Leto, P. ; Giroletti, M. ; Richards, J. L. ; Max-Moerbeck, W. ; Readhead, A. C.S. / Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009. In: Astronomy and Astrophysics. 2017 ; Vol. 603.
@article{9fc05f4be32e42b5b04fea532c3f5c2e,
title = "Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009",
abstract = "Context. We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1, which includes, among other instruments, MAGIC, VERITAS, Whipple 10 m, and Fermi-LAT to cover the γ-ray range from 0.1 GeV to 20 TeV; RXTE and Swift to cover wavelengths from UV tohard X-rays; and GASP-WEBT, which provides coverage of radio and optical wavelengths. Optical polarization measurements were provided for a fraction of the campaign by the Steward and St. Petersburg observatories. We evaluate the variability of the source and interband correlations, the γ-ray flaring activity occurring in May 2009, and interpret the results within two synchrotron self-Compton (SSC) scenarios. Aims. The multiband variability observed during the full campaign is addressed in terms of the fractional variability, and the possible correlations are studied by calculating the discrete correlation function for each pair of energy bands where the significance was evaluated with dedicated Monte Carlo simulations. The space of SSC model parameters is probed following a dedicated grid-scan strategy, allowing for a wide range of models to be tested and offering a study of the degeneracy of model-to-data agreement in the individual model parameters, hence providing a less biased interpretation than the {"}single-curve SSC model adjustment{"} typically reported in the literature. Methods. We find an increase in the fractional variability with energy, while no significant interband correlations of flux changes are found on the basis of the acquired data set. The SSC model grid-scan shows that the flaring activity around May 22 cannot be modeled adequately with a one-zone SSC scenario (using an electron energy distribution with two breaks), while it can be suitably described within a two (independent) zone SSC scenario. Here, one zone is responsible for the quiescent emission from the averaged 4.5-month observing period, while the other one, which is spatially separated from the first, dominates the flaring emission occurring at X-rays and very-high-energy (>100 GeV, VHE) γ rays. The flaring activity from May 1, which coincides with a rotation of the electric vector polarization angle (EVPA), cannot be satisfactorily reproduced by either a one-zone or a two-independent-zone SSC model, yet this is partially affected by the lack of strictly simultaneous observations and the presence of large flux changes on sub-hour timescales (detected at VHE γ rays). Results. The higher variability in the VHE emission and lack of correlation with the X-ray emission indicate that, at least during the 4.5-month observing campaign in 2009, the highest energy (and most variable) electrons that are responsible for the VHE γ rays do not make a dominant contribution to the ~1 keV emission. Alternatively, there could be a very variable component contributing to the VHE γ-ray emission in addition to that coming from the SSC scenario. The studies with our dedicated SSC grid-scan show that there is some degeneracy in both the one-zone and the two-zone SSC scenarios probed, with several combinations of model parameters yielding a similar model-to-data agreement, and some parameters better constrained than others. The observed γ-ray flaring activity, with the EVPA rotation coincident with the first γ-ray flare, resembles those reported previously for low frequency peaked blazars, hence suggesting that there are many similarities in the flaring mechanisms of blazars with different jet properties.",
keywords = "BL Lacertae objects: individual: Markarian 501, Methods: data analysis",
author = "Ahnen, {M. L.} and S. Ansoldi and Antonelli, {L. A.} and P. Antoranz and A. Babic and B. Banerjee and P. Bangale and {Barres De Almeida}, U. and Barrio, {J. A.} and {Becerra Gonz{\'a}lez}, J. and W. Bednarek and E. Bernardini and A. Berti and B. Biasuzzi and A. Biland and O. Blanch and S. Bonnefoy and G. Bonnoli and F. Borracci and T. Bretz and S. Buson and A. Carosi and A. Chatterjee and R. Clavero and P. Colin and E. Colombo and Contreras, {J. L.} and J. Cortina and S. Covino and {Da Vela}, P. and F. Dazzi and {De Angelis}, A. and {De Lotto}, B. and {De O{\~n}a Wilhelmi}, E. and {Di Pierro}, F. and M. Doert and A. Dom{\'i}nguez and {Dominis Prester}, D. and D. Dorner and M. Doro and S. Einecke and {Eisenacher Glawion}, D. and D. Elsaesser and M. Engelkemeier and {Fallah Ramazani}, V. and A. Fern{\'a}ndez-Barral and D. Fidalgo and Fonseca, {M. V.} and L. Font and K. Frantzen and C. Fruck and D. Galindo and {Garc{\'i}a L{\'o}pez}, {R. J.} and M. Garczarczyk and {Garrido Terrats}, D. and M. Gaug and P. Giammaria and N. Godinović and {Gonz{\'a}lez Mu{\~n}oz}, A. and D. Gora and D. Guberman and D. Hadasch and A. Hahn and Y. Hanabata and M. Hayashida and J. Herrera and J. Hose and D. Hrupec and G. Hughes and W. Idec and K. Kodani and Y. Konno and H. Kubo and J. Kushida and {La Barbera}, A. and D. Lelas and E. Lindfors and S. Lombardi and F. Longo and M. L{\'o}pez and R. L{\'o}pez-Coto and P. Majumdar and M. Makariev and K. Mallot and G. Maneva and M. Manganaro and K. Mannheim and L. Maraschi and B. Marcote and M. Mariotti and M. Mart{\'i}nez and D. Mazin and U. Menzel and Miranda, {J. M.} and R. Mirzoyan and A. Moralejo and E. Moretti and D. Nakajima and V. Neustroev and A. Niedzwiecki and {Nievas Rosillo}, M. and K. Nilsson and K. Nishijima and K. Noda and L. Nogu{\'e}s and A. Overkemping and S. Paiano and J. Palacio and M. Palatiello and D. Paneque and R. Paoletti and Paredes, {J. M.} and X. Paredes-Fortuny and G. Pedaletti and M. Peresano and L. Perri and M. Persic and J. Poutanen and {Prada Moroni}, {P. G.} and E. Prandini and I. Puljak and I. Reichardt and W. Rhode and M. Rib{\'o} and J. Rico and {Rodriguez Garcia}, J. and T. Saito and K. Satalecka and S. Schr{\"o}der and C. Schultz and T. Schweizer and Shore, {S. N.} and A. Sillanp{\"a}{\"a} and J. Sitarek and I. Snidaric and D. Sobczynska and A. Stamerra and T. Steinbring and M. Strzys and T. Surić and L. Takalo and F. Tavecchio and P. Temnikov and T. Terzić and D. Tescaro and M. Teshima and J. Thaele and Torres, {D. F.} and T. Toyama and A. Treves and G. Vanzo and V. Verguilov and I. Vovk and Ward, {J. E.} and M. Will and Wu, {M. H.} and R. Zanin and Abeysekara, {A. U.} and S. Archambault and A. Archer and W. Benbow and R. Bird and M. Buchovecky and Buckley, {J. H.} and V. Bugaev and Connolly, {M. P.} and W. Cui and Dickinson, {H. J.} and A. Falcone and Q. Feng and Finley, {J. P.} and H. Fleischhack and A. Flinders and L. Fortson and Gillanders, {G. H.} and S. Griffin and J. Grube and M. H{\"u}tten and D. Hanna and J. Holder and Humensky, {T. B.} and P. Kaaret and P. Kar and N. Kelley-Hoskins and M. Kertzman and D. Kieda and M. Krause and F. Krennrich and Lang, {M. J.} and G. Maier and A. McCann and P. Moriarty and R. Mukherjee and D. Nieto and S. O'Brien and Ong, {R. A.} and N. Otte and N. Park and J. Perkins and A. Pichel and M. Pohl and A. Popkow and E. Pueschel and J. Quinn and K. Ragan and Reynolds, {P. T.} and Richards, {G. T.} and E. Roache and Rovero, {A. C.} and C. Rulten and I. Sadeh and M. Santander and Sembroski, {G. H.} and K. Shahinyan and I. Telezhinsky and Tucci, {J. V.} and J. Tyler and Wakely, {S. P.} and A. Weinstein and P. Wilcox and A. Wilhelm and Williams, {D. A.} and B. Zitzer and S. Razzaque and M. Villata and Raiteri, {C. M.} and Aller, {H. D.} and Aller, {M. F.} and Larionov, {V. M.} and Arkharov, {A. A.} and Blinov, {D. A.} and Efimova, {N. V.} and Grishina, {T. S.} and Hagen-Thorn, {V. A.} and Kopatskaya, {E. N.} and Larionova, {L. V.} and Larionova, {E. G.} and Morozova, {D. A.} and Troitsky, {I. S.} and R. Ligustri and P. Calcidese and A. Berdyugin and Kurtanidze, {O. M.} and Nikolashvili, {M. G.} and Kimeridze, {G. N.} and Sigua, {L. A.} and Kurtanidze, {S. O.} and Chigladze, {R. A.} and Chen, {W. P.} and E. Koptelova and T. Sakamoto and Sadun, {A. C.} and Moody, {J. W.} and C. Pace and R. Pearson and Y. Yatsu and Y. Mori and A. Carraminyana and L. Carrasco and {De La Fuente}, E. and Norris, {J. P.} and Smith, {P. S.} and A. Wehrle and Gurwell, {M. A.} and A. Zook and C. Pagani and M. Perri and M. Capalbi and A. Cesarini and Krimm, {H. A.} and Kovalev, {Y. Y.} and Kovalev, {Yu A.} and E. Ros and Pushkarev, {A. B.} and Lister, {M. L.} and Sokolovsky, {K. V.} and M. Kadler and G. Piner and A. L{\"a}hteenm{\"a}ki and M. Tornikoski and E. Angelakis and Krichbaum, {T. P.} and I. Nestoras and L. Fuhrmann and Zensus, {J. A.} and P. Cassaro and A. Orlati and G. MacCaferri and P. Leto and M. Giroletti and Richards, {J. L.} and W. Max-Moerbeck and Readhead, {A. C.S.}",
year = "2017",
month = "7",
day = "1",
doi = "10.1051/0004-6361/201629540",
language = "English (US)",
volume = "603",
journal = "Astronomy and Astrophysics",
issn = "0004-6361",
publisher = "EDP Sciences",

}

TY - JOUR

T1 - Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009

AU - Ahnen, M. L.

AU - Ansoldi, S.

AU - Antonelli, L. A.

AU - Antoranz, P.

AU - Babic, A.

AU - Banerjee, B.

AU - Bangale, P.

AU - Barres De Almeida, U.

AU - Barrio, J. A.

AU - Becerra González, J.

AU - Bednarek, W.

AU - Bernardini, E.

AU - Berti, A.

AU - Biasuzzi, B.

AU - Biland, A.

AU - Blanch, O.

AU - Bonnefoy, S.

AU - Bonnoli, G.

AU - Borracci, F.

AU - Bretz, T.

AU - Buson, S.

AU - Carosi, A.

AU - Chatterjee, A.

AU - Clavero, R.

AU - Colin, P.

AU - Colombo, E.

AU - Contreras, J. L.

AU - Cortina, J.

AU - Covino, S.

AU - Da Vela, P.

AU - Dazzi, F.

AU - De Angelis, A.

AU - De Lotto, B.

AU - De Oña Wilhelmi, E.

AU - Di Pierro, F.

AU - Doert, M.

AU - Domínguez, A.

AU - Dominis Prester, D.

AU - Dorner, D.

AU - Doro, M.

AU - Einecke, S.

AU - Eisenacher Glawion, D.

AU - Elsaesser, D.

AU - Engelkemeier, M.

AU - Fallah Ramazani, V.

AU - Fernández-Barral, A.

AU - Fidalgo, D.

AU - Fonseca, M. V.

AU - Font, L.

AU - Frantzen, K.

AU - Fruck, C.

AU - Galindo, D.

AU - García López, R. J.

AU - Garczarczyk, M.

AU - Garrido Terrats, D.

AU - Gaug, M.

AU - Giammaria, P.

AU - Godinović, N.

AU - González Muñoz, A.

AU - Gora, D.

AU - Guberman, D.

AU - Hadasch, D.

AU - Hahn, A.

AU - Hanabata, Y.

AU - Hayashida, M.

AU - Herrera, J.

AU - Hose, J.

AU - Hrupec, D.

AU - Hughes, G.

AU - Idec, W.

AU - Kodani, K.

AU - Konno, Y.

AU - Kubo, H.

AU - Kushida, J.

AU - La Barbera, A.

AU - Lelas, D.

AU - Lindfors, E.

AU - Lombardi, S.

AU - Longo, F.

AU - López, M.

AU - López-Coto, R.

AU - Majumdar, P.

AU - Makariev, M.

AU - Mallot, K.

AU - Maneva, G.

AU - Manganaro, M.

AU - Mannheim, K.

AU - Maraschi, L.

AU - Marcote, B.

AU - Mariotti, M.

AU - Martínez, M.

AU - Mazin, D.

AU - Menzel, U.

AU - Miranda, J. M.

AU - Mirzoyan, R.

AU - Moralejo, A.

AU - Moretti, E.

AU - Nakajima, D.

AU - Neustroev, V.

AU - Niedzwiecki, A.

AU - Nievas Rosillo, M.

AU - Nilsson, K.

AU - Nishijima, K.

AU - Noda, K.

AU - Nogués, L.

AU - Overkemping, A.

AU - Paiano, S.

AU - Palacio, J.

AU - Palatiello, M.

AU - Paneque, D.

AU - Paoletti, R.

AU - Paredes, J. M.

AU - Paredes-Fortuny, X.

AU - Pedaletti, G.

AU - Peresano, M.

AU - Perri, L.

AU - Persic, M.

AU - Poutanen, J.

AU - Prada Moroni, P. G.

AU - Prandini, E.

AU - Puljak, I.

AU - Reichardt, I.

AU - Rhode, W.

AU - Ribó, M.

AU - Rico, J.

AU - Rodriguez Garcia, J.

AU - Saito, T.

AU - Satalecka, K.

AU - Schröder, S.

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PY - 2017/7/1

Y1 - 2017/7/1

N2 - Context. We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1, which includes, among other instruments, MAGIC, VERITAS, Whipple 10 m, and Fermi-LAT to cover the γ-ray range from 0.1 GeV to 20 TeV; RXTE and Swift to cover wavelengths from UV tohard X-rays; and GASP-WEBT, which provides coverage of radio and optical wavelengths. Optical polarization measurements were provided for a fraction of the campaign by the Steward and St. Petersburg observatories. We evaluate the variability of the source and interband correlations, the γ-ray flaring activity occurring in May 2009, and interpret the results within two synchrotron self-Compton (SSC) scenarios. Aims. The multiband variability observed during the full campaign is addressed in terms of the fractional variability, and the possible correlations are studied by calculating the discrete correlation function for each pair of energy bands where the significance was evaluated with dedicated Monte Carlo simulations. The space of SSC model parameters is probed following a dedicated grid-scan strategy, allowing for a wide range of models to be tested and offering a study of the degeneracy of model-to-data agreement in the individual model parameters, hence providing a less biased interpretation than the "single-curve SSC model adjustment" typically reported in the literature. Methods. We find an increase in the fractional variability with energy, while no significant interband correlations of flux changes are found on the basis of the acquired data set. The SSC model grid-scan shows that the flaring activity around May 22 cannot be modeled adequately with a one-zone SSC scenario (using an electron energy distribution with two breaks), while it can be suitably described within a two (independent) zone SSC scenario. Here, one zone is responsible for the quiescent emission from the averaged 4.5-month observing period, while the other one, which is spatially separated from the first, dominates the flaring emission occurring at X-rays and very-high-energy (>100 GeV, VHE) γ rays. The flaring activity from May 1, which coincides with a rotation of the electric vector polarization angle (EVPA), cannot be satisfactorily reproduced by either a one-zone or a two-independent-zone SSC model, yet this is partially affected by the lack of strictly simultaneous observations and the presence of large flux changes on sub-hour timescales (detected at VHE γ rays). Results. The higher variability in the VHE emission and lack of correlation with the X-ray emission indicate that, at least during the 4.5-month observing campaign in 2009, the highest energy (and most variable) electrons that are responsible for the VHE γ rays do not make a dominant contribution to the ~1 keV emission. Alternatively, there could be a very variable component contributing to the VHE γ-ray emission in addition to that coming from the SSC scenario. The studies with our dedicated SSC grid-scan show that there is some degeneracy in both the one-zone and the two-zone SSC scenarios probed, with several combinations of model parameters yielding a similar model-to-data agreement, and some parameters better constrained than others. The observed γ-ray flaring activity, with the EVPA rotation coincident with the first γ-ray flare, resembles those reported previously for low frequency peaked blazars, hence suggesting that there are many similarities in the flaring mechanisms of blazars with different jet properties.

AB - Context. We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1, which includes, among other instruments, MAGIC, VERITAS, Whipple 10 m, and Fermi-LAT to cover the γ-ray range from 0.1 GeV to 20 TeV; RXTE and Swift to cover wavelengths from UV tohard X-rays; and GASP-WEBT, which provides coverage of radio and optical wavelengths. Optical polarization measurements were provided for a fraction of the campaign by the Steward and St. Petersburg observatories. We evaluate the variability of the source and interband correlations, the γ-ray flaring activity occurring in May 2009, and interpret the results within two synchrotron self-Compton (SSC) scenarios. Aims. The multiband variability observed during the full campaign is addressed in terms of the fractional variability, and the possible correlations are studied by calculating the discrete correlation function for each pair of energy bands where the significance was evaluated with dedicated Monte Carlo simulations. The space of SSC model parameters is probed following a dedicated grid-scan strategy, allowing for a wide range of models to be tested and offering a study of the degeneracy of model-to-data agreement in the individual model parameters, hence providing a less biased interpretation than the "single-curve SSC model adjustment" typically reported in the literature. Methods. We find an increase in the fractional variability with energy, while no significant interband correlations of flux changes are found on the basis of the acquired data set. The SSC model grid-scan shows that the flaring activity around May 22 cannot be modeled adequately with a one-zone SSC scenario (using an electron energy distribution with two breaks), while it can be suitably described within a two (independent) zone SSC scenario. Here, one zone is responsible for the quiescent emission from the averaged 4.5-month observing period, while the other one, which is spatially separated from the first, dominates the flaring emission occurring at X-rays and very-high-energy (>100 GeV, VHE) γ rays. The flaring activity from May 1, which coincides with a rotation of the electric vector polarization angle (EVPA), cannot be satisfactorily reproduced by either a one-zone or a two-independent-zone SSC model, yet this is partially affected by the lack of strictly simultaneous observations and the presence of large flux changes on sub-hour timescales (detected at VHE γ rays). Results. The higher variability in the VHE emission and lack of correlation with the X-ray emission indicate that, at least during the 4.5-month observing campaign in 2009, the highest energy (and most variable) electrons that are responsible for the VHE γ rays do not make a dominant contribution to the ~1 keV emission. Alternatively, there could be a very variable component contributing to the VHE γ-ray emission in addition to that coming from the SSC scenario. The studies with our dedicated SSC grid-scan show that there is some degeneracy in both the one-zone and the two-zone SSC scenarios probed, with several combinations of model parameters yielding a similar model-to-data agreement, and some parameters better constrained than others. The observed γ-ray flaring activity, with the EVPA rotation coincident with the first γ-ray flare, resembles those reported previously for low frequency peaked blazars, hence suggesting that there are many similarities in the flaring mechanisms of blazars with different jet properties.

KW - BL Lacertae objects: individual: Markarian 501

KW - Methods: data analysis

UR - http://www.scopus.com/inward/record.url?scp=85021894732&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85021894732&partnerID=8YFLogxK

U2 - 10.1051/0004-6361/201629540

DO - 10.1051/0004-6361/201629540

M3 - Article

AN - SCOPUS:85021894732

VL - 603

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

SN - 0004-6361

M1 - A31

ER -