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Title: The γ-ray spectrum of the core of Centaurus A as observed with H.E.S.S. and Fermi-LAT

Abstract

Centaurus A (Cen A) is the nearest radio galaxy discovered as a very-high-energy (VHE; 100 GeV–100 TeV) γ-ray source by the High Energy Stereoscopic System (H.E.S.S.). It is a faint VHE γ-ray emitter, though its VHE flux exceeds both the extrapolation from early Fermi-LAT observations as well as expectations from a (misaligned) single-zone synchrotron-self Compton (SSC) description. The latter satisfactorily reproduces the emission from Cen A at lower energies up to a few GeV. New observations with H.E.S.S., comparable in exposure time to those previously reported, were performed and eight years of Fermi-LAT data were accumulated to clarify the spectral characteristics of the γ-ray emission from the core of Cen A. The results allow us for the first time to achieve the goal of constructing a representative, contemporaneous γ-ray core spectrum of Cen A over almost five orders of magnitude in energy. Advanced analysis methods, including the template fitting method, allow detection in the VHE range of the core with a statistical significance of 12σ on the basis of 213 hours of total exposure time. The spectrum in the energy range of 250 GeV–6 TeV is compatible with a power-law function with a photon index Γ = 2.52 ± 0.13statmore » ± 0.20sys. An updated Fermi-LAT analysis provides evidence for spectral hardening by ΔΓ ≃ 0.4 ± 0.1 at γ-ray energies above 2.8+1.0-0.6 GeV at a level of 4.0σ. The fact that the spectrum hardens at GeV energies and extends into the VHE regime disfavour a single-zone SSC interpretation for the overall spectral energy distribution (SED) of the core and is suggestive of a new γ-ray emitting component connecting the high-energy emission above the break energy to the one observed at VHE energies. Finally, the absence of significant variability at both GeV and TeV energies does not yet allow disentanglement of the physical nature of this component, though a jet-related origin is possible and a simple two-zone SED model fit is provided to this end.« less

Authors:
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Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
Contributing Org.:
H.E.S.S. Collaboration; Fermi-LAT Collaboration
OSTI Identifier:
1490361
Grant/Contract Number:  
AC02-76SF00515
Resource Type:
Accepted Manuscript
Journal Name:
Astronomy and Astrophysics
Additional Journal Information:
Journal Volume: 619; Journal ID: ISSN 0004-6361
Publisher:
EDP Sciences
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; gamma rays: galaxies / radiation mechanisms: non-thermal

Citation Formats

Abdalla, H., Abramowski, A., Aharonian, F., Ait Benkhali, F., Angüner, E. O., Arakawa, M., Armand, C., Arrieta, M., Backes, M., Balzer, A., Barnard, M., Becherini, Y., Becker Tjus, J., Berge, D., Bernhard, S., Bernlöhr, K., Blackwell, R., Böttcher, M., Boisson, C., Bolmont, J., Bonnefoy, S., Bordas, P., Bregeon, J., Brun, F., Brun, P., Bryan, M., Büchele, M., Bulik, T., Capasso, M., Caroff, S., Carosi, A., Casanova, S., Cerruti, M., Chakraborty, N., Chaves, R. C. G., Chen, A., Chevalier, J., Colafrancesco, S., Condon, B., Conrad, J., Davids, I. D., Decock, J., Deil, C., Devin, J., deWilt, P., Dirson, L., Djannati-Ataï, A., Donath, A., Drury, L. O’C., Dyks, J., Edwards, T., Egberts, K., Emery, G., Ernenwein, J. -P., Eschbach, S., Farnier, C., Fegan, S., Fernandes, M. V., Fiasson, A., Fontaine, G., Funk, S., Füßling, M., Gabici, S., Gallant, Y. A., Garrigoux, T., Gaté, F., Giavitto, G., Glawion, D., Glicenstein, J. F., Gottschall, D., Grondin, M. -H., Hahn, J., Haupt, M., Hawkes, J., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hofmann, W., Hoischen, C., Holch, T. L., Holler, M., Horns, D., Ivascenko, A., Iwasaki, H., Jacholkowska, A., Jamrozy, M., Jankowsky, D., Jankowsky, F., Jingo, M., Jouvin, L., Jung-Richardt, I., Kastendieck, M. A., Katarzyński, K., Katsuragawa, M., Katz, U., Kerszberg, D., Khangulyan, D., Khélifi, B., King, J., Klepser, S., Klochkov, D., Kluźniak, W., Komin, Nu., Kosack, K., Krakau, S., Kraus, M., Krüger, P. P., Laffon, H., Lamanna, G., Lau, J., Lefaucheur, J., Lemière, A., Lemoine-Goumard, M., Lenain, J. -P., Leser, E., Lohse, T., Lorentz, M., Liu, R., López-Coto, R., Lypova, I., Malyshev, D., Marandon, V., Marcowith, A., Mariaud, C., Marx, R., Maurin, G., Maxted, N., Mayer, M., Meintjes, P. J., Meyer, M., Mitchell, A. M. W., Moderski, R., Mohamed, M., Mohrmann, L., Morå, K., Moulin, E., Murach, T., Nakashima, S., de Naurois, M., Ndiyavala, H., Niederwanger, F., Niemiec, J., Oakes, L., O’Brien, P., Odaka, H., Ohm, S., Ostrowski, M., Oya, I., Padovani, M., Panter, M., Parsons, R. D., Pekeur, N. W., Pelletier, G., Perennes, C., Petrucci, P. -O., Peyaud, B., Piel, Q., Pita, S., Poireau, V., Prokhorov, D. A., Prokoph, H., Pühlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Rauth, R., Reimer, A., Reimer, O., Renaud, M., de los Reyes, R., Rieger, F., Rinchiuso, L., Romoli, C., Rowell, G., Rudak, B., Rulten, C. B., Sahakian, V., Saito, S., Sanchez, D. A., Santangelo, A., Sasaki, M., Schlickeiser, R., Schüssler, F., Schulz, A., Schwanke, U., Schwemmer, S., Seglar-Arroyo, M., Seyffert, A. S., Shafi, N., Shilon, I., Shiningayamwe, K., Simoni, R., Sol, H., Spanier, F., Spir-Jacob, M., Stawarz, Ł., Steenkamp, R., Stegmann, C., Steppa, C., Sushch, I., Takahashi, T., Tavernet, J. -P., Tavernier, T., Taylor, A. M., Terrier, R., Tibaldo, L., Tiziani, D., Tluczykont, M., Trichard, C., Tsirou, M., Tsuji, N., Tuffs, R., Uchiyama, Y., van der Walt, D. J., van Eldik, C., van Rensburg, C., van Soelen, B., Vasileiadis, G., Veh, J., Venter, C., Viana, A., Vincent, P., Vink, J., Voisin, F., Völk, H. J., Vuillaume, T., Wadiasingh, Z., Wagner, S. J., Wagner, P., Wagner, R. M., White, R., Wierzcholska, A., Willmann, P., Wörnlein, A., Wouters, D., Yang, R., Zaborov, D., Zacharias, M., Zanin, R., Zdziarski, A. A., Zech, A., Zefi, F., Ziegler, A., Zorn, J., Żywucka;, N., Magill, J. D., Buson, S., Cheung, C. C., Perkins, J. S., and Tanaka, Y. The γ-ray spectrum of the core of Centaurus A as observed with H.E.S.S. and Fermi-LAT. United States: N. p., 2018. Web. doi:10.1051/0004-6361/201832640.
Abdalla, H., Abramowski, A., Aharonian, F., Ait Benkhali, F., Angüner, E. O., Arakawa, M., Armand, C., Arrieta, M., Backes, M., Balzer, A., Barnard, M., Becherini, Y., Becker Tjus, J., Berge, D., Bernhard, S., Bernlöhr, K., Blackwell, R., Böttcher, M., Boisson, C., Bolmont, J., Bonnefoy, S., Bordas, P., Bregeon, J., Brun, F., Brun, P., Bryan, M., Büchele, M., Bulik, T., Capasso, M., Caroff, S., Carosi, A., Casanova, S., Cerruti, M., Chakraborty, N., Chaves, R. C. G., Chen, A., Chevalier, J., Colafrancesco, S., Condon, B., Conrad, J., Davids, I. D., Decock, J., Deil, C., Devin, J., deWilt, P., Dirson, L., Djannati-Ataï, A., Donath, A., Drury, L. O’C., Dyks, J., Edwards, T., Egberts, K., Emery, G., Ernenwein, J. -P., Eschbach, S., Farnier, C., Fegan, S., Fernandes, M. V., Fiasson, A., Fontaine, G., Funk, S., Füßling, M., Gabici, S., Gallant, Y. A., Garrigoux, T., Gaté, F., Giavitto, G., Glawion, D., Glicenstein, J. F., Gottschall, D., Grondin, M. -H., Hahn, J., Haupt, M., Hawkes, J., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hofmann, W., Hoischen, C., Holch, T. L., Holler, M., Horns, D., Ivascenko, A., Iwasaki, H., Jacholkowska, A., Jamrozy, M., Jankowsky, D., Jankowsky, F., Jingo, M., Jouvin, L., Jung-Richardt, I., Kastendieck, M. A., Katarzyński, K., Katsuragawa, M., Katz, U., Kerszberg, D., Khangulyan, D., Khélifi, B., King, J., Klepser, S., Klochkov, D., Kluźniak, W., Komin, Nu., Kosack, K., Krakau, S., Kraus, M., Krüger, P. P., Laffon, H., Lamanna, G., Lau, J., Lefaucheur, J., Lemière, A., Lemoine-Goumard, M., Lenain, J. -P., Leser, E., Lohse, T., Lorentz, M., Liu, R., López-Coto, R., Lypova, I., Malyshev, D., Marandon, V., Marcowith, A., Mariaud, C., Marx, R., Maurin, G., Maxted, N., Mayer, M., Meintjes, P. J., Meyer, M., Mitchell, A. M. W., Moderski, R., Mohamed, M., Mohrmann, L., Morå, K., Moulin, E., Murach, T., Nakashima, S., de Naurois, M., Ndiyavala, H., Niederwanger, F., Niemiec, J., Oakes, L., O’Brien, P., Odaka, H., Ohm, S., Ostrowski, M., Oya, I., Padovani, M., Panter, M., Parsons, R. D., Pekeur, N. W., Pelletier, G., Perennes, C., Petrucci, P. -O., Peyaud, B., Piel, Q., Pita, S., Poireau, V., Prokhorov, D. A., Prokoph, H., Pühlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Rauth, R., Reimer, A., Reimer, O., Renaud, M., de los Reyes, R., Rieger, F., Rinchiuso, L., Romoli, C., Rowell, G., Rudak, B., Rulten, C. B., Sahakian, V., Saito, S., Sanchez, D. A., Santangelo, A., Sasaki, M., Schlickeiser, R., Schüssler, F., Schulz, A., Schwanke, U., Schwemmer, S., Seglar-Arroyo, M., Seyffert, A. S., Shafi, N., Shilon, I., Shiningayamwe, K., Simoni, R., Sol, H., Spanier, F., Spir-Jacob, M., Stawarz, Ł., Steenkamp, R., Stegmann, C., Steppa, C., Sushch, I., Takahashi, T., Tavernet, J. -P., Tavernier, T., Taylor, A. M., Terrier, R., Tibaldo, L., Tiziani, D., Tluczykont, M., Trichard, C., Tsirou, M., Tsuji, N., Tuffs, R., Uchiyama, Y., van der Walt, D. J., van Eldik, C., van Rensburg, C., van Soelen, B., Vasileiadis, G., Veh, J., Venter, C., Viana, A., Vincent, P., Vink, J., Voisin, F., Völk, H. J., Vuillaume, T., Wadiasingh, Z., Wagner, S. J., Wagner, P., Wagner, R. M., White, R., Wierzcholska, A., Willmann, P., Wörnlein, A., Wouters, D., Yang, R., Zaborov, D., Zacharias, M., Zanin, R., Zdziarski, A. A., Zech, A., Zefi, F., Ziegler, A., Zorn, J., Żywucka;, N., Magill, J. D., Buson, S., Cheung, C. C., Perkins, J. S., & Tanaka, Y. The γ-ray spectrum of the core of Centaurus A as observed with H.E.S.S. and Fermi-LAT. United States. https://doi.org/10.1051/0004-6361/201832640
Abdalla, H., Abramowski, A., Aharonian, F., Ait Benkhali, F., Angüner, E. O., Arakawa, M., Armand, C., Arrieta, M., Backes, M., Balzer, A., Barnard, M., Becherini, Y., Becker Tjus, J., Berge, D., Bernhard, S., Bernlöhr, K., Blackwell, R., Böttcher, M., Boisson, C., Bolmont, J., Bonnefoy, S., Bordas, P., Bregeon, J., Brun, F., Brun, P., Bryan, M., Büchele, M., Bulik, T., Capasso, M., Caroff, S., Carosi, A., Casanova, S., Cerruti, M., Chakraborty, N., Chaves, R. C. G., Chen, A., Chevalier, J., Colafrancesco, S., Condon, B., Conrad, J., Davids, I. D., Decock, J., Deil, C., Devin, J., deWilt, P., Dirson, L., Djannati-Ataï, A., Donath, A., Drury, L. O’C., Dyks, J., Edwards, T., Egberts, K., Emery, G., Ernenwein, J. -P., Eschbach, S., Farnier, C., Fegan, S., Fernandes, M. V., Fiasson, A., Fontaine, G., Funk, S., Füßling, M., Gabici, S., Gallant, Y. A., Garrigoux, T., Gaté, F., Giavitto, G., Glawion, D., Glicenstein, J. F., Gottschall, D., Grondin, M. -H., Hahn, J., Haupt, M., Hawkes, J., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hofmann, W., Hoischen, C., Holch, T. L., Holler, M., Horns, D., Ivascenko, A., Iwasaki, H., Jacholkowska, A., Jamrozy, M., Jankowsky, D., Jankowsky, F., Jingo, M., Jouvin, L., Jung-Richardt, I., Kastendieck, M. A., Katarzyński, K., Katsuragawa, M., Katz, U., Kerszberg, D., Khangulyan, D., Khélifi, B., King, J., Klepser, S., Klochkov, D., Kluźniak, W., Komin, Nu., Kosack, K., Krakau, S., Kraus, M., Krüger, P. P., Laffon, H., Lamanna, G., Lau, J., Lefaucheur, J., Lemière, A., Lemoine-Goumard, M., Lenain, J. -P., Leser, E., Lohse, T., Lorentz, M., Liu, R., López-Coto, R., Lypova, I., Malyshev, D., Marandon, V., Marcowith, A., Mariaud, C., Marx, R., Maurin, G., Maxted, N., Mayer, M., Meintjes, P. J., Meyer, M., Mitchell, A. M. W., Moderski, R., Mohamed, M., Mohrmann, L., Morå, K., Moulin, E., Murach, T., Nakashima, S., de Naurois, M., Ndiyavala, H., Niederwanger, F., Niemiec, J., Oakes, L., O’Brien, P., Odaka, H., Ohm, S., Ostrowski, M., Oya, I., Padovani, M., Panter, M., Parsons, R. D., Pekeur, N. W., Pelletier, G., Perennes, C., Petrucci, P. -O., Peyaud, B., Piel, Q., Pita, S., Poireau, V., Prokhorov, D. A., Prokoph, H., Pühlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Rauth, R., Reimer, A., Reimer, O., Renaud, M., de los Reyes, R., Rieger, F., Rinchiuso, L., Romoli, C., Rowell, G., Rudak, B., Rulten, C. B., Sahakian, V., Saito, S., Sanchez, D. A., Santangelo, A., Sasaki, M., Schlickeiser, R., Schüssler, F., Schulz, A., Schwanke, U., Schwemmer, S., Seglar-Arroyo, M., Seyffert, A. S., Shafi, N., Shilon, I., Shiningayamwe, K., Simoni, R., Sol, H., Spanier, F., Spir-Jacob, M., Stawarz, Ł., Steenkamp, R., Stegmann, C., Steppa, C., Sushch, I., Takahashi, T., Tavernet, J. -P., Tavernier, T., Taylor, A. M., Terrier, R., Tibaldo, L., Tiziani, D., Tluczykont, M., Trichard, C., Tsirou, M., Tsuji, N., Tuffs, R., Uchiyama, Y., van der Walt, D. J., van Eldik, C., van Rensburg, C., van Soelen, B., Vasileiadis, G., Veh, J., Venter, C., Viana, A., Vincent, P., Vink, J., Voisin, F., Völk, H. J., Vuillaume, T., Wadiasingh, Z., Wagner, S. J., Wagner, P., Wagner, R. M., White, R., Wierzcholska, A., Willmann, P., Wörnlein, A., Wouters, D., Yang, R., Zaborov, D., Zacharias, M., Zanin, R., Zdziarski, A. A., Zech, A., Zefi, F., Ziegler, A., Zorn, J., Żywucka;, N., Magill, J. D., Buson, S., Cheung, C. C., Perkins, J. S., and Tanaka, Y. Thu . "The γ-ray spectrum of the core of Centaurus A as observed with H.E.S.S. and Fermi-LAT". United States. https://doi.org/10.1051/0004-6361/201832640. https://www.osti.gov/servlets/purl/1490361.
@article{osti_1490361,
title = {The γ-ray spectrum of the core of Centaurus A as observed with H.E.S.S. and Fermi-LAT},
author = {Abdalla, H. and Abramowski, A. and Aharonian, F. and Ait Benkhali, F. and Angüner, E. O. and Arakawa, M. and Armand, C. and Arrieta, M. and Backes, M. and Balzer, A. and Barnard, M. and Becherini, Y. and Becker Tjus, J. and Berge, D. and Bernhard, S. and Bernlöhr, K. and Blackwell, R. and Böttcher, M. and Boisson, C. and Bolmont, J. and Bonnefoy, S. and Bordas, P. and Bregeon, J. and Brun, F. and Brun, P. and Bryan, M. and Büchele, M. and Bulik, T. and Capasso, M. and Caroff, S. and Carosi, A. and Casanova, S. and Cerruti, M. and Chakraborty, N. and Chaves, R. C. G. and Chen, A. and Chevalier, J. and Colafrancesco, S. and Condon, B. and Conrad, J. and Davids, I. D. and Decock, J. and Deil, C. and Devin, J. and deWilt, P. and Dirson, L. and Djannati-Ataï, A. and Donath, A. and Drury, L. O’C. and Dyks, J. and Edwards, T. and Egberts, K. and Emery, G. and Ernenwein, J. -P. and Eschbach, S. and Farnier, C. and Fegan, S. and Fernandes, M. V. and Fiasson, A. and Fontaine, G. and Funk, S. and Füßling, M. and Gabici, S. and Gallant, Y. A. and Garrigoux, T. and Gaté, F. and Giavitto, G. and Glawion, D. and Glicenstein, J. F. and Gottschall, D. and Grondin, M. -H. and Hahn, J. and Haupt, M. and Hawkes, J. and Heinzelmann, G. and Henri, G. and Hermann, G. and Hinton, J. A. and Hofmann, W. and Hoischen, C. and Holch, T. L. and Holler, M. and Horns, D. and Ivascenko, A. and Iwasaki, H. and Jacholkowska, A. and Jamrozy, M. and Jankowsky, D. and Jankowsky, F. and Jingo, M. and Jouvin, L. and Jung-Richardt, I. and Kastendieck, M. A. and Katarzyński, K. and Katsuragawa, M. and Katz, U. and Kerszberg, D. and Khangulyan, D. and Khélifi, B. and King, J. and Klepser, S. and Klochkov, D. and Kluźniak, W. and Komin, Nu. and Kosack, K. and Krakau, S. and Kraus, M. and Krüger, P. P. and Laffon, H. and Lamanna, G. and Lau, J. and Lefaucheur, J. and Lemière, A. and Lemoine-Goumard, M. and Lenain, J. -P. and Leser, E. and Lohse, T. and Lorentz, M. and Liu, R. and López-Coto, R. and Lypova, I. and Malyshev, D. and Marandon, V. and Marcowith, A. and Mariaud, C. and Marx, R. and Maurin, G. and Maxted, N. and Mayer, M. and Meintjes, P. J. and Meyer, M. and Mitchell, A. M. W. and Moderski, R. and Mohamed, M. and Mohrmann, L. and Morå, K. and Moulin, E. and Murach, T. and Nakashima, S. and de Naurois, M. and Ndiyavala, H. and Niederwanger, F. and Niemiec, J. and Oakes, L. and O’Brien, P. and Odaka, H. and Ohm, S. and Ostrowski, M. and Oya, I. and Padovani, M. and Panter, M. and Parsons, R. D. and Pekeur, N. W. and Pelletier, G. and Perennes, C. and Petrucci, P. -O. and Peyaud, B. and Piel, Q. and Pita, S. and Poireau, V. and Prokhorov, D. A. and Prokoph, H. and Pühlhofer, G. and Punch, M. and Quirrenbach, A. and Raab, S. and Rauth, R. and Reimer, A. and Reimer, O. and Renaud, M. and de los Reyes, R. and Rieger, F. and Rinchiuso, L. and Romoli, C. and Rowell, G. and Rudak, B. and Rulten, C. B. and Sahakian, V. and Saito, S. and Sanchez, D. A. and Santangelo, A. and Sasaki, M. and Schlickeiser, R. and Schüssler, F. and Schulz, A. and Schwanke, U. and Schwemmer, S. and Seglar-Arroyo, M. and Seyffert, A. S. and Shafi, N. and Shilon, I. and Shiningayamwe, K. and Simoni, R. and Sol, H. and Spanier, F. and Spir-Jacob, M. and Stawarz, Ł. and Steenkamp, R. and Stegmann, C. and Steppa, C. and Sushch, I. and Takahashi, T. and Tavernet, J. -P. and Tavernier, T. and Taylor, A. M. and Terrier, R. and Tibaldo, L. and Tiziani, D. and Tluczykont, M. and Trichard, C. and Tsirou, M. and Tsuji, N. and Tuffs, R. and Uchiyama, Y. and van der Walt, D. J. and van Eldik, C. and van Rensburg, C. and van Soelen, B. and Vasileiadis, G. and Veh, J. and Venter, C. and Viana, A. and Vincent, P. and Vink, J. and Voisin, F. and Völk, H. J. and Vuillaume, T. and Wadiasingh, Z. and Wagner, S. J. and Wagner, P. and Wagner, R. M. and White, R. and Wierzcholska, A. and Willmann, P. and Wörnlein, A. and Wouters, D. and Yang, R. and Zaborov, D. and Zacharias, M. and Zanin, R. and Zdziarski, A. A. and Zech, A. and Zefi, F. and Ziegler, A. and Zorn, J. and Żywucka;, N. and Magill, J. D. and Buson, S. and Cheung, C. C. and Perkins, J. S. and Tanaka, Y.},
abstractNote = {Centaurus A (Cen A) is the nearest radio galaxy discovered as a very-high-energy (VHE; 100 GeV–100 TeV) γ-ray source by the High Energy Stereoscopic System (H.E.S.S.). It is a faint VHE γ-ray emitter, though its VHE flux exceeds both the extrapolation from early Fermi-LAT observations as well as expectations from a (misaligned) single-zone synchrotron-self Compton (SSC) description. The latter satisfactorily reproduces the emission from Cen A at lower energies up to a few GeV. New observations with H.E.S.S., comparable in exposure time to those previously reported, were performed and eight years of Fermi-LAT data were accumulated to clarify the spectral characteristics of the γ-ray emission from the core of Cen A. The results allow us for the first time to achieve the goal of constructing a representative, contemporaneous γ-ray core spectrum of Cen A over almost five orders of magnitude in energy. Advanced analysis methods, including the template fitting method, allow detection in the VHE range of the core with a statistical significance of 12σ on the basis of 213 hours of total exposure time. The spectrum in the energy range of 250 GeV–6 TeV is compatible with a power-law function with a photon index Γ = 2.52 ± 0.13stat ± 0.20sys. An updated Fermi-LAT analysis provides evidence for spectral hardening by ΔΓ ≃ 0.4 ± 0.1 at γ-ray energies above 2.8+1.0-0.6 GeV at a level of 4.0σ. The fact that the spectrum hardens at GeV energies and extends into the VHE regime disfavour a single-zone SSC interpretation for the overall spectral energy distribution (SED) of the core and is suggestive of a new γ-ray emitting component connecting the high-energy emission above the break energy to the one observed at VHE energies. Finally, the absence of significant variability at both GeV and TeV energies does not yet allow disentanglement of the physical nature of this component, though a jet-related origin is possible and a simple two-zone SED model fit is provided to this end.},
doi = {10.1051/0004-6361/201832640},
journal = {Astronomy and Astrophysics},
number = ,
volume = 619,
place = {United States},
year = {Thu Nov 01 00:00:00 EDT 2018},
month = {Thu Nov 01 00:00:00 EDT 2018}
}

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FERMI LARGE AREA TELESCOPE THIRD SOURCE CATALOG
journal, June 2015

  • Acero, F.; Ackermann, M.; Ajello, M.
  • The Astrophysical Journal Supplement Series, Vol. 218, Issue 2
  • DOI: 10.1088/0067-0049/218/2/23

Unified Schemes for Radio-Loud Active Galactic Nuclei
journal, June 1995

  • Urry, C. Megan; Padovani, Paolo
  • Publications of the Astronomical Society of the Pacific, Vol. 107
  • DOI: 10.1086/133630

Studies of active galactic nuclei with CTA
journal, March 2013


Discovery of a new extragalactic population of energetic particles
journal, March 2017


Structured jets in TeV BL Lac objects and radiogalaxies: Implications for the observed properties
journal, March 2005


Stochastic Acceleration and the Evolution of Spectral Distributions in Synchro-Self-Compton Sources: a Self-Consistent Modeling of Blazars’ Flares
journal, September 2011


The hard X-Ray Continuum of cen a Observed with Integral spi
journal, May 2014

  • Burke, Mark J.; Jourdain, Elisabeth; Roques, Jean-Pierre
  • The Astrophysical Journal, Vol. 787, Issue 1
  • DOI: 10.1088/0004-637X/787/1/50

FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: DATA PROCESSING, SKY MAPS, AND BASIC RESULTS
journal, February 2009

  • Hinshaw, G.; Weiland, J. L.; Hill, R. S.
  • The Astrophysical Journal Supplement Series, Vol. 180, Issue 2
  • DOI: 10.1088/0067-0049/180/2/225

TANAMI monitoring of Centaurus A: The complex dynamics in the inner parsec of an extragalactic jet
journal, September 2014


A jet model for the gamma-ray emitting blazar 3C 279
journal, September 1992

  • Maraschi, L.; Ghisellini, G.; Celotti, A.
  • The Astrophysical Journal, Vol. 397
  • DOI: 10.1086/186531

Discovery of very high Energy γ-Ray Emission from Centaurus a with H.E.S.S.
journal, March 2009


Nonthermal Processes in Black Hole-Jet Magnetospheres — Invited Review
journal, August 2011


An Analysis of the Synchrotron Self-Compton Model for the Multi--Wave Band Spectra of Blazars
journal, April 1996

  • Bloom, Steven D.; Marscher, Alan P.
  • The Astrophysical Journal, Vol. 461
  • DOI: 10.1086/177092

FERMI LARGE AREA TELESCOPE SECOND SOURCE CATALOG
journal, March 2012

  • Nolan, P. L.; Abdo, A. A.; Ackermann, M.
  • The Astrophysical Journal Supplement Series, Vol. 199, Issue 2
  • DOI: 10.1088/0067-0049/199/2/31

The Likelihood Analysis of EGRET Data
journal, April 1996

  • Mattox, J. R.; Bertsch, D. L.; Chiang, J.
  • The Astrophysical Journal, Vol. 461
  • DOI: 10.1086/177068

Temporal and spectral gamma-ray properties of Mkn 421 above 250 GeV from CAT observations between 1996 and 2000
journal, August 2001


VERY HIGH ENERGY GAMMA-RAY-INDUCED PAIR CASCADES IN THE RADIATION FIELDS OF DUST TORI OF ACTIVE GALACTIC NUCLEI: APPLICATION TO Cen A
journal, January 2011


Gamma-ray fluxes from the core emission of Centaurus A: a puzzle solved
journal, May 2014

  • Fraija, Nissim
  • Monthly Notices of the Royal Astronomical Society, Vol. 441, Issue 2
  • DOI: 10.1093/mnras/stu652

NuSTAR AND XMM-NEWTON OBSERVATIONS OF THE HARD X-RAY SPECTRUM OF CENTAURUS A
journal, March 2016


Background modelling in very-high-energy γ -ray astronomy
journal, April 2007


BRIGHT ACTIVE GALACTIC NUCLEI SOURCE LIST FROM THE FIRST THREE MONTHS OF THE FERMI LARGE AREA TELESCOPE ALL-SKY SURVEY
journal, July 2009


TeV Gamma Rays from Ultrahigh Energy Cosmic Ray Interactions in the Cores of Active Galactic Nuclei: Lessons from Centaurus A
journal, January 2010

  • Kachelrieß, M.; Ostapchenko, S.; Tomàs, R.
  • Publications of the Astronomical Society of Australia, Vol. 27, Issue 4
  • DOI: 10.1071/AS09072

Where to stick your data points: The treatment of measurements within wide bins
journal, February 1995

  • Lafferty, G. D.; Wyatt, T. R.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 355, Issue 2-3
  • DOI: 10.1016/0168-9002(94)01112-5

Centaurus A at Hard X-Rays and Soft Gamma-Rays
journal, January 2010

  • Steinle, H.
  • Publications of the Astronomical Society of Australia, Vol. 27, Issue 4
  • DOI: 10.1071/AS09070

Centaurus A - NGC 5128
journal, August 1998


Log-parabolic spectra and particle acceleration in blazars: III. SSC emission in the TeV band from Mkn 501
journal, March 2006


Radio and X‐Ray Observations of the Jet in Centaurus A
journal, August 2003

  • Hardcastle, M. J.; Worrall, D. M.; Kraft, R. P.
  • The Astrophysical Journal, Vol. 593, Issue 1
  • DOI: 10.1086/376519

A new analysis strategy for detection of faint γ-ray sources with Imaging Atmospheric Cherenkov Telescopes
journal, July 2011


A lepto-hadronic model for high-energy emission from FR I radiogalaxies
journal, June 2011


THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION
journal, May 2009


Resolving the innermost parsec of Centaurus A at mid-infrared wavelengths
journal, June 2007


The status of the HESS project
journal, April 2004


Centaurus A as TeV γ -ray and possible UHE cosmic-ray source
journal, October 2009


Observations of the Crab nebula with HESS
journal, September 2006

  • Aharonian, F.; Akhperjanian, A. G.; Bazer-Bachi, A. R.
  • Astronomy & Astrophysics, Vol. 457, Issue 3
  • DOI: 10.1051/0004-6361:20065351

High‐Energy Gamma Rays from FR I Jets
journal, November 2003

  • Stawarz, Ł.; Sikora, M.; Ostrowski, M.
  • The Astrophysical Journal, Vol. 597, Issue 1
  • DOI: 10.1086/378290

Absorption of nuclear  -rays on the starlight radiation in FR I sources: the case of Centaurus A
journal, October 2006


The Morphology of Extragalactic Radio Sources of High and Low Luminosity
journal, April 1974

  • Fanaroff, B. L.; Riley, J. M.
  • Monthly Notices of the Royal Astronomical Society, Vol. 167, Issue 1
  • DOI: 10.1093/mnras/167.1.31P

FERMI LARGE AREA TELESCOPE VIEW OF THE CORE OF THE RADIO GALAXY CENTAURUS A
journal, July 2010


Hadronic modeling of TeV AGN: Gammas and neutrinos
conference, January 2017

  • Cerruti, M.; Zech, A.; Emery, G.
  • HIGH ENERGY GAMMA-RAY ASTRONOMY: 6th International Meeting on High Energy Gamma-Ray Astronomy, AIP Conference Proceedings
  • DOI: 10.1063/1.4968973

Analysis methods for results in gamma-ray astronomy
journal, September 1983

  • Li, T. -P.; Ma, Y. -Q.
  • The Astrophysical Journal, Vol. 272
  • DOI: 10.1086/161295

3FHL: The Third Catalog of Hard Fermi -LAT Sources
journal, September 2017

  • Ajello, M.; Atwood, W. B.; Baldini, L.
  • The Astrophysical Journal Supplement Series, Vol. 232, Issue 2
  • DOI: 10.3847/1538-4365/aa8221

GeV emission from the nearby radio galaxy Centaurus A
journal, June 1999


First results on the performance of the HEGRA IACT array
journal, December 1997


Deep observation of the giant radio lobes of Centaurus A with the Fermi Large Area Telescope
journal, May 2012


Chandra and XMM‐Newton Observations of the Nucleus of Centaurus A
journal, September 2004

  • Evans, D. A.; Kraft, R. P.; Worrall, D. M.
  • The Astrophysical Journal, Vol. 612, Issue 2
  • DOI: 10.1086/422806

One-zone synchrotron self-Compton model for the core emission of Centaurus A revisited
journal, January 2014


DEVELOPMENT OF THE MODEL OF GALACTIC INTERSTELLAR EMISSION FOR STANDARD POINT-SOURCE ANALYSIS OF FERMI LARGE AREA TELESCOPE DATA
journal, April 2016

  • Acero, F.; Ackermann, M.; Ajello, M.
  • The Astrophysical Journal Supplement Series, Vol. 223, Issue 2
  • DOI: 10.3847/0067-0049/223/2/26

OSSE Observations of Gamma-Ray Emission from Centaurus A
journal, August 1995

  • Kinzer, R. L.; Johnson, W. N.; Dermer, C. D.
  • The Astrophysical Journal, Vol. 449
  • DOI: 10.1086/176036

Spitzer Observations of Centaurus A: Infrared Synchrotron Emission from the Northern Lobe
journal, July 2006

  • Brookes, M. H.; Lawrence, C. R.; Keene, J.
  • The Astrophysical Journal, Vol. 646, Issue 1
  • DOI: 10.1086/506472

Ten Milliparsec-Scale Structure of the Nucleus Region in Centaurus A
journal, April 2006

  • Horiuchi, Shinji; Meier, David L.; Preston, Robert A.
  • Publications of the Astronomical Society of Japan, Vol. 58, Issue 2
  • DOI: 10.1093/pasj/58.2.211

Chandra Observations of the X‐Ray Jet in Centaurus A
journal, April 2002

  • Kraft, R. P.; Forman, W. R.; Jones, C.
  • The Astrophysical Journal, Vol. 569, Issue 1
  • DOI: 10.1086/339062

The infrared jet in Centaurus A: multiwavelength constraints on emission mechanisms and particle acceleration
journal, May 2006

  • Hardcastle, M. J.; Kraft, R. P.; Worrall, D. M.
  • Monthly Notices of the Royal Astronomical Society: Letters, Vol. 368, Issue 1
  • DOI: 10.1111/j.1745-3933.2006.00146.x

The BL Lac heart of Centaurus A
journal, July 2001


Modelling TeV γ-ray emission from the kiloparsec-scale jets of Centaurus A and M87: TeV jets in Cen A & M87
journal, May 2011


A Monte Carlo template based analysis for air-Cherenkov arrays
journal, April 2014


Hadronic-origin TeV γ rays and ultrahigh energy cosmic rays from Centaurus A
journal, February 2012


Evidence for a Second Component in the High-Energy core Emission from Centaurus a?
journal, May 2013


Log-parabolic spectra and particle acceleration in blazars: II. The BeppoSAX wide band X-ray spectra of Mkn 501
journal, July 2004


Development of the Model of Galactic Interstellar Emission for Standard Point-Source Analysis of FERMI Large Area Telescope Data
text, January 2016

  • Acero, F.; Ackermann, Markus; Ajello, M.
  • Deutsches Elektronen-Synchrotron, DESY, Hamburg
  • DOI: 10.3204/pubdb-2016-06164

3FHL: The Third Catalog of Hard Fermi -LAT Sources
text, January 2017


Resolving the innermost parsec of Centaurus A at mid-infrared wavelengths
text, January 2007


Discovery of very high energy gamma-ray emission from Centaurus A with H.E.S.S
text, January 2009


Fermi Large Area Telescope View of the Core of the Radio Galaxy Centaurus A
text, January 2010


Deep Observation of the Giant Radio Lobes of Centaurus A with the Fermi Large Area Telescope
text, January 2012


Hadronic-Origin TeV gamma-Rays and Ultra-High Energy Cosmic Rays from Centaurus A
text, January 2012


Studies of active galactic nuclei with CTA
text, January 2012


A Monte Carlo Template based analysis for Air-Cherenkov Arrays
text, January 2014


The hard X-ray continuum of Cen A observed with INTEGRAL SPI
text, January 2014


Discovery of a new extragalactic source population of energetic particles
text, January 2016


3FHL: The Third Catalog of Hard Fermi-LAT Sources
text, January 2017


The BL Lac heart of Centaurus A
text, January 2001


Radio and X-ray observations of the jet in Centaurus A
text, January 2003


Chandra and XMM-Newton Observations of the Nucleus of Centaurus A
text, January 2004


Background Modelling in Very-High-Energy gamma-ray Astronomy
text, January 2006


GeV emission from the nearby radio galaxy Centaurus A
text, January 1999


Works referencing / citing this record:

Very high-energy constraints on the infrared extragalactic background light
journal, August 2019


Gamma-ray observations of low-luminosity active galactic nuclei
journal, January 2020

  • de Menezes, Raniere; Nemmen, Rodrigo; Finke, Justin D.
  • Monthly Notices of the Royal Astronomical Society, Vol. 492, Issue 3
  • DOI: 10.1093/mnras/staa083

Non-thermal emission in radio galaxy lobes – II. Centaurus A, Centaurus B, and NGC 6251
journal, September 2019

  • Persic, Massimo; Rephaeli, Yoel
  • Monthly Notices of the Royal Astronomical Society, Vol. 490, Issue 2
  • DOI: 10.1093/mnras/stz2527

Centaurus A: Hard X-ray and High-Energy Gamma-Ray Light Curve Correlation
journal, April 2019


The High Energy View of FR0 Radio Galaxies
journal, September 2019


Inverse Compton Scattering of Starlight in the Kiloparsec-scale Jet in Centaurus A: The Origin of Excess TeV γ -Ray Emission
journal, June 2019


Fermi Large Area Telescope Fourth Source Catalog
journal, March 2020

  • Abdollahi, S.; Acero, F.; Ackermann, M.
  • The Astrophysical Journal Supplement Series, Vol. 247, Issue 1
  • DOI: 10.3847/1538-4365/ab6bcb

Fermi Large Area Telescope Fourth Source Catalog
text, January 2020

  • Abdollahi, S.; Acero, F.; Ackermann, Markus
  • Deutsches Elektronen-Synchrotron, DESY, Hamburg
  • DOI: 10.3204/pubdb-2020-01400

Fermi Large Area Telescope Fourth Source Catalog
collection, January 2020


Very high-energy constraints on the Infrared Extragalactic Background Light
text, January 2019


The High Energy View of FR0 Radio Galaxies
preprint, January 2019


Gamma-ray observations of low-luminosity active galactic nuclei
text, January 2020