---
_id: '11622'
abstract:
- lang: eng
text: 'The recent discovery of low-amplitude dipolar oscillation mixed modes in
massive red giants indicates the presence of a missing physical process inside
their cores. Stars more massive than ∼ 1.3 M⊙ are known to develop a convective
core during the main-sequence: the dynamo process triggered by this convection
could be the origin of a strong magnetic field inside the core of the star, trapped
when it becomes stably stratified and for the rest of its evolution. The presence
of highly magnetized white dwarfs strengthens the hypothesis of buried fossil
magnetic fields inside the core of evolved low-mass stars. If such a fossil field
exists, it should affect the mixed modes of red giants as they are sensitive to
processes affecting the deepest layers of these stars. The impact of a magnetic
field on dipolar oscillations modes was one of Pr. Michael J. Thompson’s research
topics during the 90s when preparing the helioseismic SoHO space mission. As the
detection of gravity modes in the Sun is still controversial, the investigation
of the solar oscillation modes did not provide any hint of the existence of a
magnetic field in the solar radiative core. Today we have access to the core of
evolved stars thanks to the asteroseismic observation of mixed modes from CoRoT,
Kepler, K2 and TESS missions. The idea of applying and generalizing the work done
for the Sun came from discussions with Pr. Michael Thompson in early 2018 before
we lost him. Following the path we drew together, we theoretically investigate
the effect of a stable axisymmetric mixed poloidal and toroidal magnetic field,
aligned with the rotation axis of the star, on the mixed modes frequencies of
a typical evolved low-mass star. This enables us to estimate the magnetic perturbations
to the eigenfrequencies of mixed dipolar modes, depending on the magnetic field
strength and the evolutionary state of the star. We conclude that strong magnetic
fields of ∼ 1MG should perturb the mixed-mode frequency pattern enough for its
effects to be detectable inside current asteroseismic data.'
acknowledgement: The authors of this work acknowledge the support received from the
PLATO CNES grant, the National Aeronautics and Space Administration under Grant
NNX15AF13G, by the National Science Foundation grant AST-1411685, the Ramon y Cajal
fellowship number RYC-2015-17697, the ERC SPIRE grant (647383), and the Fundation
L’Oréal-Unesco-Académie des sciences.
alternative_title:
- Astrophysics and Space Science Proceedings
article_processing_charge: No
arxiv: 1
author:
- first_name: Lisa Annabelle
full_name: Bugnet, Lisa Annabelle
id: d9edb345-f866-11ec-9b37-d119b5234501
last_name: Bugnet
orcid: 0000-0003-0142-4000
- first_name: V.
full_name: Prat, V.
last_name: Prat
- first_name: S.
full_name: Mathis, S.
last_name: Mathis
- first_name: R. A.
full_name: García, R. A.
last_name: García
- first_name: S.
full_name: Mathur, S.
last_name: Mathur
- first_name: K.
full_name: Augustson, K.
last_name: Augustson
- first_name: C.
full_name: Neiner, C.
last_name: Neiner
- first_name: M. J.
full_name: Thompson, M. J.
last_name: Thompson
citation:
ama: 'Bugnet LA, Prat V, Mathis S, et al. The impact of a fossil magnetic field
on dipolar mixed-mode frequencies in sub- and red-giant stars. In: Monteiro M,
Garcia RA, Christensen-Dalsgaard J, McIntosh SW, eds. Dynamics of the Sun and
Stars. Vol 57. 1st ed. ASSSP. Cham: Springer Nature; 2020:251-257. doi:10.1007/978-3-030-55336-4_33'
apa: 'Bugnet, L. A., Prat, V., Mathis, S., García, R. A., Mathur, S., Augustson,
K., … Thompson, M. J. (2020). The impact of a fossil magnetic field on dipolar
mixed-mode frequencies in sub- and red-giant stars. In M. Monteiro, R. A. Garcia,
J. Christensen-Dalsgaard, & S. W. McIntosh (Eds.), Dynamics of the Sun
and Stars (1st ed., Vol. 57, pp. 251–257). Cham: Springer Nature. https://doi.org/10.1007/978-3-030-55336-4_33'
chicago: 'Bugnet, Lisa Annabelle, V. Prat, S. Mathis, R. A. García, S. Mathur, K.
Augustson, C. Neiner, and M. J. Thompson. “The Impact of a Fossil Magnetic Field
on Dipolar Mixed-Mode Frequencies in Sub- and Red-Giant Stars.” In Dynamics
of the Sun and Stars, edited by Mario Monteiro, Rafael A Garcia, Jorgen Christensen-Dalsgaard,
and Scott W McIntosh, 1st ed., 57:251–57. ASSSP. Cham: Springer Nature, 2020.
https://doi.org/10.1007/978-3-030-55336-4_33.'
ieee: 'L. A. Bugnet et al., “The impact of a fossil magnetic field on dipolar
mixed-mode frequencies in sub- and red-giant stars,” in Dynamics of the Sun
and Stars, 1st ed., vol. 57, M. Monteiro, R. A. Garcia, J. Christensen-Dalsgaard,
and S. W. McIntosh, Eds. Cham: Springer Nature, 2020, pp. 251–257.'
ista: 'Bugnet LA, Prat V, Mathis S, García RA, Mathur S, Augustson K, Neiner C,
Thompson MJ. 2020.The impact of a fossil magnetic field on dipolar mixed-mode
frequencies in sub- and red-giant stars. In: Dynamics of the Sun and Stars. Astrophysics
and Space Science Proceedings, vol. 57, 251–257.'
mla: Bugnet, Lisa Annabelle, et al. “The Impact of a Fossil Magnetic Field on Dipolar
Mixed-Mode Frequencies in Sub- and Red-Giant Stars.” Dynamics of the Sun and
Stars, edited by Mario Monteiro et al., 1st ed., vol. 57, Springer Nature,
2020, pp. 251–57, doi:10.1007/978-3-030-55336-4_33.
short: L.A. Bugnet, V. Prat, S. Mathis, R.A. García, S. Mathur, K. Augustson, C.
Neiner, M.J. Thompson, in:, M. Monteiro, R.A. Garcia, J. Christensen-Dalsgaard,
S.W. McIntosh (Eds.), Dynamics of the Sun and Stars, 1st ed., Springer Nature,
Cham, 2020, pp. 251–257.
date_created: 2022-07-19T08:25:41Z
date_published: 2020-12-19T00:00:00Z
date_updated: 2024-10-14T11:42:19Z
day: '19'
doi: 10.1007/978-3-030-55336-4_33
edition: '1'
editor:
- first_name: Mario
full_name: Monteiro, Mario
last_name: Monteiro
- first_name: Rafael A
full_name: Garcia, Rafael A
last_name: Garcia
- first_name: Jorgen
full_name: Christensen-Dalsgaard, Jorgen
last_name: Christensen-Dalsgaard
- first_name: Scott W
full_name: McIntosh, Scott W
last_name: McIntosh
extern: '1'
external_id:
arxiv:
- '2012.08684'
intvolume: ' 57'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2012.08684
month: '12'
oa: 1
oa_version: Preprint
page: 251-257
place: Cham
publication: Dynamics of the Sun and Stars
publication_identifier:
eisbn:
- 978-3-030-55336-4
eissn:
- 1570-6605
isbn:
- 978-3-030-55335-7
issn:
- 1570-6591
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
series_title: ASSSP
status: public
title: The impact of a fossil magnetic field on dipolar mixed-mode frequencies in
sub- and red-giant stars
type: book_chapter
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 57
year: '2020'
...
---
OA_place: repository
OA_type: green
_id: '18726'
abstract:
- lang: eng
text: The high sensitivity of JWST will open a new window on the end of the cosmological
dark ages. Small stellar clusters, with a stellar mass of several × 106 M⊙, and
low-mass black holes (BHs), with a mass of several $× 105 M⊙ should be directly
detectable out to redshift z = 10, and individual supernovae (SNe) and gamma ray
burst GRB afterglows are bright enough to be visible beyond this redshift. Dense
primordial gas, in the process of collapsing from large scales to form protogalaxies,
may also be possible to image through diffuse recombination line emission, possibly
even before stars or BHs are formed. In this article, I discuss the key physical
processes that are expected to have determined the sizes of the first star–clusters
and black holes, and the prospect of studying these objects by direct detections
with JWST and with other instruments. The direct light emitted by the very first
stellar clusters and intermediate-mass black holes at z > 10 will likely fall
below JWST’s detection threshold. However, JWST could reveal a decline at the
faint-end of the high-redshift luminosity function, and thereby shed light on
radiative and other feedback effects that operate at these early epochs. JWST
will also have the sensitivity to detect individual SNe from beyond z = 10. In
a dedicated survey lasting for several weeks, thousands of SNe could be detected
at z > 6, with a redshift distribution extending to the formation of the very
first stars at z ≳ 15. Using these SNe as tracers may be the only method to map
out the earliest stages of the cosmic star–formation history. Finally, we point
out that studying the earliest objects at high redshift will also offer a new
window on the primordial power spectrum, on ∼100 times smaller scales than probed
by current large-scale structure data.
alternative_title:
- Astrophysics and Space Science Proceedings
article_processing_charge: No
arxiv: 1
author:
- first_name: Zoltán
full_name: Haiman, Zoltán
id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
last_name: Haiman
orcid: 0000-0003-3633-5403
citation:
ama: 'Haiman Z. Observing the first stars and black holes. In: Astrophysics and
Space Science Proceedings. Dordrecht: Springer Nature; 2009:385-418. doi:10.1007/978-1-4020-9457-6_15'
apa: 'Haiman, Z. (2009). Observing the first stars and black holes. In Astrophysics
and Space Science Proceedings (pp. 385–418). Dordrecht: Springer Nature. https://doi.org/10.1007/978-1-4020-9457-6_15'
chicago: 'Haiman, Zoltán. “Observing the First Stars and Black Holes.” In Astrophysics
and Space Science Proceedings, 385–418. Dordrecht: Springer Nature, 2009.
https://doi.org/10.1007/978-1-4020-9457-6_15.'
ieee: Z. Haiman, “Observing the first stars and black holes,” in Astrophysics
and Space Science Proceedings, 2009, pp. 385–418.
ista: Haiman Z. 2009. Observing the first stars and black holes. Astrophysics and
Space Science Proceedings. , Astrophysics and Space Science Proceedings, , 385–418.
mla: Haiman, Zoltán. “Observing the First Stars and Black Holes.” Astrophysics
and Space Science Proceedings, Springer Nature, 2009, pp. 385–418, doi:10.1007/978-1-4020-9457-6_15.
short: Z. Haiman, in:, Astrophysics and Space Science Proceedings, Springer Nature,
Dordrecht, 2009, pp. 385–418.
date_created: 2025-01-03T12:09:18Z
date_published: 2009-01-01T00:00:00Z
date_updated: 2025-01-03T12:14:49Z
day: '01'
doi: 10.1007/978-1-4020-9457-6_15
extern: '1'
external_id:
arxiv:
- '0809.3926'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/0809.3926
month: '01'
oa: 1
oa_version: Preprint
page: 385-418
place: Dordrecht
publication: Astrophysics and Space Science Proceedings
publication_identifier:
eisbn:
- '9781402094576'
eissn:
- 1570-6605
isbn:
- '9781402094569'
issn:
- 1570-6591
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Observing the first stars and black holes
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2009'
...
---
OA_place: repository
OA_type: green
_id: '18735'
abstract:
- lang: eng
text: The high sensitivity of JWST will open a new window on the end of the cosmological
dark ages. Small stellar clusters, with a stellar mass of several × 106 M⊙, and
low-mass black holes (BHs), with a mass of several $× 105 M⊙ should be directly
detectable out to redshift z = 10, and individual supernovae (SNe) and gamma ray
burst GRB afterglows are bright enough to be visible beyond this redshift. Dense
primordial gas, in the process of collapsing from large scales to form protogalaxies,
may also be possible to image through diffuse recombination line emission, possibly
even before stars or BHs are formed. In this article, I discuss the key physical
processes that are expected to have determined the sizes of the first star–clusters
and black holes, and the prospect of studying these objects by direct detections
with JWST and with other instruments. The direct light emitted by the very first
stellar clusters and intermediate-mass black holes at z > 10 will likely fall
below JWST’s detection threshold. However, JWST could reveal a decline at the
faint-end of the high-redshift luminosity function, and thereby shed light on
radiative and other feedback effects that operate at these early epochs. JWST
will also have the sensitivity to detect individual SNe from beyond z = 10. In
a dedicated survey lasting for several weeks, thousands of SNe could be detected
at z > 6, with a redshift distribution extending to the formation of the very
first stars at z ≳ 15. Using these SNe as tracers may be the only method to map
out the earliest stages of the cosmic star–formation history. Finally, we point
out that studying the earliest objects at high redshift will also offer a new
window on the primordial power spectrum, on ∼100 times smaller scales than probed
by current large-scale structure data.
alternative_title:
- Astrophysics and Space Science Proceedings
article_processing_charge: No
arxiv: 1
author:
- first_name: Zoltán
full_name: Haiman, Zoltán
id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
last_name: Haiman
orcid: 0000-0003-3633-5403
citation:
ama: 'Haiman Z. Observing the First Stars and Black Holes. In: Thronson HA, Stiavelli
M, Tielens A, eds. Astrophysics in the Next Decade. Springer Nature; 2009:385-418.
doi:10.1007/978-1-4020-9457-6_15'
apa: Haiman, Z. (2009). Observing the First Stars and Black Holes. In H. A. Thronson,
M. Stiavelli, & A. Tielens (Eds.), Astrophysics in the Next Decade
(pp. 385–418). Springer Nature. https://doi.org/10.1007/978-1-4020-9457-6_15
chicago: Haiman, Zoltán. “Observing the First Stars and Black Holes.” In Astrophysics
in the Next Decade, edited by Harley A. Thronson, Massimo Stiavelli, and Alexander
Tielens, 385–418. Springer Nature, 2009. https://doi.org/10.1007/978-1-4020-9457-6_15.
ieee: Z. Haiman, “Observing the First Stars and Black Holes,” in Astrophysics
in the Next Decade, H. A. Thronson, M. Stiavelli, and A. Tielens, Eds. Springer
Nature, 2009, pp. 385–418.
ista: 'Haiman Z. 2009.Observing the First Stars and Black Holes. In: Astrophysics
in the Next Decade. Astrophysics and Space Science Proceedings, , 385–418.'
mla: Haiman, Zoltán. “Observing the First Stars and Black Holes.” Astrophysics
in the Next Decade, edited by Harley A. Thronson et al., Springer Nature,
2009, pp. 385–418, doi:10.1007/978-1-4020-9457-6_15.
short: Z. Haiman, in:, H.A. Thronson, M. Stiavelli, A. Tielens (Eds.), Astrophysics
in the Next Decade, Springer Nature, 2009, pp. 385–418.
date_created: 2025-01-03T12:29:16Z
date_published: 2009-02-11T00:00:00Z
date_updated: 2025-01-07T12:52:13Z
day: '11'
doi: 10.1007/978-1-4020-9457-6_15
editor:
- first_name: Harley A.
full_name: Thronson, Harley A.
last_name: Thronson
- first_name: Massimo
full_name: Stiavelli, Massimo
last_name: Stiavelli
- first_name: Alexander
full_name: Tielens, Alexander
last_name: Tielens
extern: '1'
external_id:
arxiv:
- '0809.3926'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/0809.3926
month: '02'
oa: 1
oa_version: Preprint
page: 385-418
publication: Astrophysics in the Next Decade
publication_identifier:
eisbn:
- '9781402094576'
eissn:
- 1570-6605
isbn:
- '9781402094569'
issn:
- 1570-6591
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Observing the First Stars and Black Holes
type: book_chapter
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2009'
...