Super-orbital variability of LS I +61 ° 303 at TeV energies

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; B. Biasuzzi; A. Biland; O. Blanch; S. Bonnefoy; G. Bonnoli; F. Borracci; T. Bretz; S. 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; C. Delgado Mendez; F. Di Pierro; A. Domínguez; D. Dominis Prester; D. Dorner; M. Doro; S. Einecke; D. Eisenacher Glawion; D. Elsaesser; 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; A. López-Oramas; 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

doi:10.1051/0004-6361/201527964

Super-orbital variability of LS I +61 ° 303 at TeV energies

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, B. Biasuzzi, A. Biland, O. Blanch, S. Bonnefoy, G. Bonnoli, F. Borracci, T. Bretz, S. BusonA. 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, C. Delgado Mendez, F. Di Pierro, A. Domínguez, D. Dominis Prester, D. Dorner, M. Doro, S. Einecke, D. Eisenacher Glawion, D. Elsaesser, 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, A. López-Oramas, 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

Research output: Contribution to journal › Article › Research › peer-review

16 Citations (Scopus)

Abstract

© 2016 ESO. Context. The gamma-ray binary LS I +61°303 is a well-established source from centimeter radio up to very high energy (VHE; E> 100 GeV). The broadband emission shows a periodicity of ∼26.5 days, coincident with the orbital period. A longer (super-orbital) period of 1667 ± 8 days was proposed from radio variability and confirmed using optical and high-energy (HE; E> 100 MeV) gamma-ray observations. In this paper, we report on a four-year campaign performed by MAGIC together with archival data concentrating on a search for a long-timescale signature in the VHE emission from LS I +61°303. Aims. We focus on the search for super-orbital modulation of the VHE emission, similar to that observed at other energies, and on the search for correlations between TeV emission and an optical determination of the extension of the circumstellar disk. Methods. A four-year campaign has been carried out using the MAGIC telescopes. The source was observed during the orbital phases when the periodic VHE outbursts have occurred (φ = 0.55-0.75, one orbit = 26.496 days). Additionally, we included archival MAGIC observations and data published by the VERITAS collaboration in these studies. For the correlation studies, LS I +61°303 has also been observed during the orbital phases where sporadic VHE emission had been detected in the past (φ = 0.75-1.0). These MAGIC observations were simultaneous with optical spectroscopy from the LIVERPOOL telescope. Results. The TeV flux of the periodical outburst in orbital phases φ = 0.5-0.75 was found to show yearly variability consistent with the long-term modulation of ∼4.5 years found in the radio band. This modulation of the TeV flux can be well described by a sine function with a best-fit period of 1610 ± 58 days. The complete data, including archival observations, span two super-orbital periods. There is no evidence for a correlation between the TeV emission and the mass-loss rate of the Be star, but this may be affected by the strong, short-timescale (as short as intra-day) variation displayed by the Hα fluxes.

Original language	English
Article number	A76
Journal	Astronomy and Astrophysics
Volume	591
DOIs	https://doi.org/10.1051/0004-6361/201527964
Publication status	Published - 1 Jan 2016

Keywords

Astroparticle physics
Binaries: general
Gamma rays: general
Stars: individual: LS I +61°303
X-rays: binaries
X-rays: individuals: LS I +61°303

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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., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., ... Nilsson, K. (2016). Super-orbital variability of LS I +61 ° 303 at TeV energies. Astronomy and Astrophysics, 591, [A76]. https://doi.org/10.1051/0004-6361/201527964

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. ; 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. ; Delgado Mendez, C. ; Di Pierro, F. ; Domínguez, A. ; Dominis Prester, D. ; Dorner, D. ; Doro, M. ; Einecke, S. ; Eisenacher Glawion, D. ; Elsaesser, D. ; 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. ; López-Oramas, A. ; 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. / Super-orbital variability of LS I +61 ° 303 at TeV energies. In: Astronomy and Astrophysics. 2016 ; Vol. 591.

@article{f1f2f4144d704b69bf9f64795e5efee0,

title = "Super-orbital variability of LS I +61 ° 303 at TeV energies",

abstract = "{\textcopyright} 2016 ESO. Context. The gamma-ray binary LS I +61°303 is a well-established source from centimeter radio up to very high energy (VHE; E> 100 GeV). The broadband emission shows a periodicity of ∼26.5 days, coincident with the orbital period. A longer (super-orbital) period of 1667 ± 8 days was proposed from radio variability and confirmed using optical and high-energy (HE; E> 100 MeV) gamma-ray observations. In this paper, we report on a four-year campaign performed by MAGIC together with archival data concentrating on a search for a long-timescale signature in the VHE emission from LS I +61°303. Aims. We focus on the search for super-orbital modulation of the VHE emission, similar to that observed at other energies, and on the search for correlations between TeV emission and an optical determination of the extension of the circumstellar disk. Methods. A four-year campaign has been carried out using the MAGIC telescopes. The source was observed during the orbital phases when the periodic VHE outbursts have occurred (φ = 0.55-0.75, one orbit = 26.496 days). Additionally, we included archival MAGIC observations and data published by the VERITAS collaboration in these studies. For the correlation studies, LS I +61°303 has also been observed during the orbital phases where sporadic VHE emission had been detected in the past (φ = 0.75-1.0). These MAGIC observations were simultaneous with optical spectroscopy from the LIVERPOOL telescope. Results. The TeV flux of the periodical outburst in orbital phases φ = 0.5-0.75 was found to show yearly variability consistent with the long-term modulation of ∼4.5 years found in the radio band. This modulation of the TeV flux can be well described by a sine function with a best-fit period of 1610 ± 58 days. The complete data, including archival observations, span two super-orbital periods. There is no evidence for a correlation between the TeV emission and the mass-loss rate of the Be star, but this may be affected by the strong, short-timescale (as short as intra-day) variation displayed by the Hα fluxes.",

keywords = "Astroparticle physics, Binaries: general, Gamma rays: general, Stars: individual: LS I +61°303, X-rays: binaries, X-rays: individuals: LS I +61°303",

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 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 {Delgado Mendez}, C. and {Di Pierro}, F. 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 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. Godinovi{\'c} 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 A. L{\'o}pez-Oramas 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",

year = "2016",

month = jan,

day = "1",

doi = "10.1051/0004-6361/201527964",

language = "English",

volume = "591",

journal = "Astronomy and Astrophysics",

issn = "0004-6361",

}

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, 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, Delgado Mendez, C, Di Pierro, F, Domínguez, A, Dominis Prester, D, Dorner, D, Doro, M, Einecke, S, Eisenacher Glawion, D, Elsaesser, D, 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, López-Oramas, A, 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 2016, 'Super-orbital variability of LS I +61 ° 303 at TeV energies', Astronomy and Astrophysics, vol. 591, A76. https://doi.org/10.1051/0004-6361/201527964

Super-orbital variability of LS I +61 ° 303 at TeV energies. / 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.; 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.; Delgado Mendez, C.; Di Pierro, F.; Domínguez, A.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Eisenacher Glawion, D.; Elsaesser, D.; 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.; López-Oramas, A.; 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.

In: Astronomy and Astrophysics, Vol. 591, A76, 01.01.2016.

Research output: Contribution to journal › Article › Research › peer-review

TY - JOUR

T1 - Super-orbital variability of LS I +61 ° 303 at TeV energies

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 - 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 - Delgado Mendez, C.

AU - Di Pierro, F.

AU - Domínguez, A.

AU - Dominis Prester, D.

AU - Dorner, D.

AU - Doro, M.

AU - Einecke, S.

AU - Eisenacher Glawion, D.

AU - Elsaesser, D.

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 - López-Oramas, A.

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.

PY - 2016/1/1

Y1 - 2016/1/1

N2 - © 2016 ESO. Context. The gamma-ray binary LS I +61°303 is a well-established source from centimeter radio up to very high energy (VHE; E> 100 GeV). The broadband emission shows a periodicity of ∼26.5 days, coincident with the orbital period. A longer (super-orbital) period of 1667 ± 8 days was proposed from radio variability and confirmed using optical and high-energy (HE; E> 100 MeV) gamma-ray observations. In this paper, we report on a four-year campaign performed by MAGIC together with archival data concentrating on a search for a long-timescale signature in the VHE emission from LS I +61°303. Aims. We focus on the search for super-orbital modulation of the VHE emission, similar to that observed at other energies, and on the search for correlations between TeV emission and an optical determination of the extension of the circumstellar disk. Methods. A four-year campaign has been carried out using the MAGIC telescopes. The source was observed during the orbital phases when the periodic VHE outbursts have occurred (φ = 0.55-0.75, one orbit = 26.496 days). Additionally, we included archival MAGIC observations and data published by the VERITAS collaboration in these studies. For the correlation studies, LS I +61°303 has also been observed during the orbital phases where sporadic VHE emission had been detected in the past (φ = 0.75-1.0). These MAGIC observations were simultaneous with optical spectroscopy from the LIVERPOOL telescope. Results. The TeV flux of the periodical outburst in orbital phases φ = 0.5-0.75 was found to show yearly variability consistent with the long-term modulation of ∼4.5 years found in the radio band. This modulation of the TeV flux can be well described by a sine function with a best-fit period of 1610 ± 58 days. The complete data, including archival observations, span two super-orbital periods. There is no evidence for a correlation between the TeV emission and the mass-loss rate of the Be star, but this may be affected by the strong, short-timescale (as short as intra-day) variation displayed by the Hα fluxes.

AB - © 2016 ESO. Context. The gamma-ray binary LS I +61°303 is a well-established source from centimeter radio up to very high energy (VHE; E> 100 GeV). The broadband emission shows a periodicity of ∼26.5 days, coincident with the orbital period. A longer (super-orbital) period of 1667 ± 8 days was proposed from radio variability and confirmed using optical and high-energy (HE; E> 100 MeV) gamma-ray observations. In this paper, we report on a four-year campaign performed by MAGIC together with archival data concentrating on a search for a long-timescale signature in the VHE emission from LS I +61°303. Aims. We focus on the search for super-orbital modulation of the VHE emission, similar to that observed at other energies, and on the search for correlations between TeV emission and an optical determination of the extension of the circumstellar disk. Methods. A four-year campaign has been carried out using the MAGIC telescopes. The source was observed during the orbital phases when the periodic VHE outbursts have occurred (φ = 0.55-0.75, one orbit = 26.496 days). Additionally, we included archival MAGIC observations and data published by the VERITAS collaboration in these studies. For the correlation studies, LS I +61°303 has also been observed during the orbital phases where sporadic VHE emission had been detected in the past (φ = 0.75-1.0). These MAGIC observations were simultaneous with optical spectroscopy from the LIVERPOOL telescope. Results. The TeV flux of the periodical outburst in orbital phases φ = 0.5-0.75 was found to show yearly variability consistent with the long-term modulation of ∼4.5 years found in the radio band. This modulation of the TeV flux can be well described by a sine function with a best-fit period of 1610 ± 58 days. The complete data, including archival observations, span two super-orbital periods. There is no evidence for a correlation between the TeV emission and the mass-loss rate of the Be star, but this may be affected by the strong, short-timescale (as short as intra-day) variation displayed by the Hα fluxes.

KW - Astroparticle physics

KW - Binaries: general

KW - Gamma rays: general

KW - Stars: individual: LS I +61°303

KW - X-rays: binaries

KW - X-rays: individuals: LS I +61°303

U2 - 10.1051/0004-6361/201527964

DO - 10.1051/0004-6361/201527964

M3 - Article

VL - 591

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

SN - 0004-6361

M1 - A76

ER -