X-rays from magnetic massive OB stars

V. Petit, D. H. Cohen, Y. Nazé, M. Gagné, R. H.D. Townsend, M. A. Leutenegger, A. Ud-Doula, S. P. Owocki, G. A. Wade

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

The magnetic activity of solar-type and low-mass stars is a well known source of coronal X-ray emission. At the other end of the main sequence, X-rays emission is instead associated with the powerful, radiatively driven winds of massive stars. Indeed, the intrinsically unstable line-driving mechanism of OB star winds gives rise to shock-heated, soft emission (∼0.5 keV) distributed throughout the wind. Recently, the latest generation of spectropolarimetric instrumentation has uncovered a population of massive OB-stars hosting strong, organized magnetic fields. The magnetic characteristics of these stars are similar to the apparently fossil magnetic fields of the chemically peculiar ApBp stars. Magnetic channeling of these OB stars' strong winds leads to the formation of large-scale shock-heated magnetospheres, which can modify UV resonance lines, create complex distributions of cooled Halpha emitting material, and radiate hard (∼2-5 keV) X-rays. This presentation summarizes our coordinated observational and modelling efforts to characterize the manifestation of these magnetospheres in the X-ray domain, providing an important contrast between the emission originating in shocks associated with the large-scale fossil fields of massive stars, and the X-rays associated with the activity of complex, dynamo-generated fields in lower-mass stars.

Original languageEnglish (US)
Title of host publicationMagnetic Fields throughout Stellar Evolution
PublisherCambridge University Press
Pages330-333
Number of pages4
EditionS302
ISBN (Print)9781107044982
DOIs
StatePublished - Aug 2014

Publication series

NameProceedings of the International Astronomical Union
NumberS302
Volume9
ISSN (Print)1743-9213
ISSN (Electronic)1743-9221

Fingerprint

magnetic stars
massive stars
stars
shock
fossils
x rays
magnetospheres
magnetosphere
fossil
magnetic field
peculiar stars
resonance lines
magnetic fields
instrumentation
modeling

All Science Journal Classification (ASJC) codes

  • Medicine (miscellaneous)
  • Astronomy and Astrophysics
  • Nutrition and Dietetics
  • Public Health, Environmental and Occupational Health
  • Space and Planetary Science

Cite this

Petit, V., Cohen, D. H., Nazé, Y., Gagné, M., Townsend, R. H. D., Leutenegger, M. A., ... Wade, G. A. (2014). X-rays from magnetic massive OB stars. In Magnetic Fields throughout Stellar Evolution (S302 ed., pp. 330-333). (Proceedings of the International Astronomical Union; Vol. 9, No. S302). Cambridge University Press. https://doi.org/10.1017/S1743921314002427
Petit, V. ; Cohen, D. H. ; Nazé, Y. ; Gagné, M. ; Townsend, R. H.D. ; Leutenegger, M. A. ; Ud-Doula, A. ; Owocki, S. P. ; Wade, G. A. / X-rays from magnetic massive OB stars. Magnetic Fields throughout Stellar Evolution. S302. ed. Cambridge University Press, 2014. pp. 330-333 (Proceedings of the International Astronomical Union; S302).
@inbook{140f0f2a59ba4a37a99f382d62432f19,
title = "X-rays from magnetic massive OB stars",
abstract = "The magnetic activity of solar-type and low-mass stars is a well known source of coronal X-ray emission. At the other end of the main sequence, X-rays emission is instead associated with the powerful, radiatively driven winds of massive stars. Indeed, the intrinsically unstable line-driving mechanism of OB star winds gives rise to shock-heated, soft emission (∼0.5 keV) distributed throughout the wind. Recently, the latest generation of spectropolarimetric instrumentation has uncovered a population of massive OB-stars hosting strong, organized magnetic fields. The magnetic characteristics of these stars are similar to the apparently fossil magnetic fields of the chemically peculiar ApBp stars. Magnetic channeling of these OB stars' strong winds leads to the formation of large-scale shock-heated magnetospheres, which can modify UV resonance lines, create complex distributions of cooled Halpha emitting material, and radiate hard (∼2-5 keV) X-rays. This presentation summarizes our coordinated observational and modelling efforts to characterize the manifestation of these magnetospheres in the X-ray domain, providing an important contrast between the emission originating in shocks associated with the large-scale fossil fields of massive stars, and the X-rays associated with the activity of complex, dynamo-generated fields in lower-mass stars.",
author = "V. Petit and Cohen, {D. H.} and Y. Naz{\'e} and M. Gagn{\'e} and Townsend, {R. H.D.} and Leutenegger, {M. A.} and A. Ud-Doula and Owocki, {S. P.} and Wade, {G. A.}",
year = "2014",
month = "8",
doi = "10.1017/S1743921314002427",
language = "English (US)",
isbn = "9781107044982",
series = "Proceedings of the International Astronomical Union",
publisher = "Cambridge University Press",
number = "S302",
pages = "330--333",
booktitle = "Magnetic Fields throughout Stellar Evolution",
address = "United Kingdom",
edition = "S302",

}

Petit, V, Cohen, DH, Nazé, Y, Gagné, M, Townsend, RHD, Leutenegger, MA, Ud-Doula, A, Owocki, SP & Wade, GA 2014, X-rays from magnetic massive OB stars. in Magnetic Fields throughout Stellar Evolution. S302 edn, Proceedings of the International Astronomical Union, no. S302, vol. 9, Cambridge University Press, pp. 330-333. https://doi.org/10.1017/S1743921314002427

X-rays from magnetic massive OB stars. / Petit, V.; Cohen, D. H.; Nazé, Y.; Gagné, M.; Townsend, R. H.D.; Leutenegger, M. A.; Ud-Doula, A.; Owocki, S. P.; Wade, G. A.

Magnetic Fields throughout Stellar Evolution. S302. ed. Cambridge University Press, 2014. p. 330-333 (Proceedings of the International Astronomical Union; Vol. 9, No. S302).

Research output: Chapter in Book/Report/Conference proceedingChapter

TY - CHAP

T1 - X-rays from magnetic massive OB stars

AU - Petit, V.

AU - Cohen, D. H.

AU - Nazé, Y.

AU - Gagné, M.

AU - Townsend, R. H.D.

AU - Leutenegger, M. A.

AU - Ud-Doula, A.

AU - Owocki, S. P.

AU - Wade, G. A.

PY - 2014/8

Y1 - 2014/8

N2 - The magnetic activity of solar-type and low-mass stars is a well known source of coronal X-ray emission. At the other end of the main sequence, X-rays emission is instead associated with the powerful, radiatively driven winds of massive stars. Indeed, the intrinsically unstable line-driving mechanism of OB star winds gives rise to shock-heated, soft emission (∼0.5 keV) distributed throughout the wind. Recently, the latest generation of spectropolarimetric instrumentation has uncovered a population of massive OB-stars hosting strong, organized magnetic fields. The magnetic characteristics of these stars are similar to the apparently fossil magnetic fields of the chemically peculiar ApBp stars. Magnetic channeling of these OB stars' strong winds leads to the formation of large-scale shock-heated magnetospheres, which can modify UV resonance lines, create complex distributions of cooled Halpha emitting material, and radiate hard (∼2-5 keV) X-rays. This presentation summarizes our coordinated observational and modelling efforts to characterize the manifestation of these magnetospheres in the X-ray domain, providing an important contrast between the emission originating in shocks associated with the large-scale fossil fields of massive stars, and the X-rays associated with the activity of complex, dynamo-generated fields in lower-mass stars.

AB - The magnetic activity of solar-type and low-mass stars is a well known source of coronal X-ray emission. At the other end of the main sequence, X-rays emission is instead associated with the powerful, radiatively driven winds of massive stars. Indeed, the intrinsically unstable line-driving mechanism of OB star winds gives rise to shock-heated, soft emission (∼0.5 keV) distributed throughout the wind. Recently, the latest generation of spectropolarimetric instrumentation has uncovered a population of massive OB-stars hosting strong, organized magnetic fields. The magnetic characteristics of these stars are similar to the apparently fossil magnetic fields of the chemically peculiar ApBp stars. Magnetic channeling of these OB stars' strong winds leads to the formation of large-scale shock-heated magnetospheres, which can modify UV resonance lines, create complex distributions of cooled Halpha emitting material, and radiate hard (∼2-5 keV) X-rays. This presentation summarizes our coordinated observational and modelling efforts to characterize the manifestation of these magnetospheres in the X-ray domain, providing an important contrast between the emission originating in shocks associated with the large-scale fossil fields of massive stars, and the X-rays associated with the activity of complex, dynamo-generated fields in lower-mass stars.

UR - http://www.scopus.com/inward/record.url?scp=84905749748&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84905749748&partnerID=8YFLogxK

U2 - 10.1017/S1743921314002427

DO - 10.1017/S1743921314002427

M3 - Chapter

AN - SCOPUS:84905749748

SN - 9781107044982

T3 - Proceedings of the International Astronomical Union

SP - 330

EP - 333

BT - Magnetic Fields throughout Stellar Evolution

PB - Cambridge University Press

ER -

Petit V, Cohen DH, Nazé Y, Gagné M, Townsend RHD, Leutenegger MA et al. X-rays from magnetic massive OB stars. In Magnetic Fields throughout Stellar Evolution. S302 ed. Cambridge University Press. 2014. p. 330-333. (Proceedings of the International Astronomical Union; S302). https://doi.org/10.1017/S1743921314002427