Cosmic-ray production from neutron escape in microquasar jets
- Autores
- Escobar, Gastón Javier; Pellizza, L. J.; Romero, Gustavo Esteban
- Año de publicación
- 2021
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- The origin of Galactic cosmic rays remains a matter of debate, but supernova remnants are commonly considered to be the main place where high-energy cosmic rays are accelerated. Nevertheless, current models predict cosmic-ray spectra that do not match observations and the efficiency of the acceleration mechanism is still undetermined. On the other hand, the contribution of other kinds of sources to the Galactic cosmic-ray population is still unclear, and merits investigation. In this work we explore a novel mechanism through which microquasars might produce cosmic rays. In this scenario, microquasar jets generate relativistic neutrons, which escape and decay outside the system; protons and electrons, created when these neutrons decay, escape to the interstellar medium as cosmic rays. The most promising scenarios arise in extremely luminous systems ($L_\mathrm{jet} \sim 10^{40}\,\mathrm{erg \, s}^{-1}$), in which the fraction of jet power deposited in cosmic rays can reach $\sim 0.001$. Slow jets ($\Gamma \lesssim 2$, where $\Gamma$ is the bulk Lorentz factor) favour neutron production. The resulting cosmic-ray spectrum is similar for protons and electrons, which share the power in the ratio given by neutron decay. The spectrum peaks at roughly half the minimum energy of the relativistic protons in the jet; it is soft (spectral index $\sim 3$) above this energy, and almost flat below. Values of spectral index steeper than $2$ are possible for cosmic rays in our model and these indeed agree with those required to explain the spectral signatures of Galactic cosmic rays, although only the most extreme microquasars provide power comparable to that of a typical supernova remnant. The mechanism explored in this work may provide stronger and softer cosmic-ray sources in the early Universe, and therefore contribute to the heating and reionisation of the intergalactic medium.
Instituto Argentino de Radioastronomía - Materia
-
Ciencias Astronómicas
cosmic rays
ISM: jets and outflows
relativistic processes - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- http://creativecommons.org/licenses/by/4.0/
- Repositorio
- Institución
- Universidad Nacional de La Plata
- OAI Identificador
- oai:sedici.unlp.edu.ar:10915/143744
Ver los metadatos del registro completo
id |
SEDICI_6c48bd7add1bc62b65a0175897a0b2b2 |
---|---|
oai_identifier_str |
oai:sedici.unlp.edu.ar:10915/143744 |
network_acronym_str |
SEDICI |
repository_id_str |
1329 |
network_name_str |
SEDICI (UNLP) |
spelling |
Cosmic-ray production from neutron escape in microquasar jetsEscobar, Gastón JavierPellizza, L. J.Romero, Gustavo EstebanCiencias Astronómicascosmic raysISM: jets and outflowsrelativistic processesThe origin of Galactic cosmic rays remains a matter of debate, but supernova remnants are commonly considered to be the main place where high-energy cosmic rays are accelerated. Nevertheless, current models predict cosmic-ray spectra that do not match observations and the efficiency of the acceleration mechanism is still undetermined. On the other hand, the contribution of other kinds of sources to the Galactic cosmic-ray population is still unclear, and merits investigation. In this work we explore a novel mechanism through which microquasars might produce cosmic rays. In this scenario, microquasar jets generate relativistic neutrons, which escape and decay outside the system; protons and electrons, created when these neutrons decay, escape to the interstellar medium as cosmic rays. The most promising scenarios arise in extremely luminous systems ($L_\mathrm{jet} \sim 10^{40}\,\mathrm{erg \, s}^{-1}$), in which the fraction of jet power deposited in cosmic rays can reach $\sim 0.001$. Slow jets ($\Gamma \lesssim 2$, where $\Gamma$ is the bulk Lorentz factor) favour neutron production. The resulting cosmic-ray spectrum is similar for protons and electrons, which share the power in the ratio given by neutron decay. The spectrum peaks at roughly half the minimum energy of the relativistic protons in the jet; it is soft (spectral index $\sim 3$) above this energy, and almost flat below. Values of spectral index steeper than $2$ are possible for cosmic rays in our model and these indeed agree with those required to explain the spectral signatures of Galactic cosmic rays, although only the most extreme microquasars provide power comparable to that of a typical supernova remnant. The mechanism explored in this work may provide stronger and softer cosmic-ray sources in the early Universe, and therefore contribute to the heating and reionisation of the intergalactic medium.Instituto Argentino de Radioastronomía2021-06-22info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfhttp://sedici.unlp.edu.ar/handle/10915/143744enginfo:eu-repo/semantics/altIdentifier/issn/0004-6361info:eu-repo/semantics/altIdentifier/issn/1432-0746info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/202039860info:eu-repo/semantics/altIdentifier/arxiv/2104.11975info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International (CC BY 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:32:26Zoai:sedici.unlp.edu.ar:10915/143744Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:32:27.094SEDICI (UNLP) - Universidad Nacional de La Platafalse |
dc.title.none.fl_str_mv |
Cosmic-ray production from neutron escape in microquasar jets |
title |
Cosmic-ray production from neutron escape in microquasar jets |
spellingShingle |
Cosmic-ray production from neutron escape in microquasar jets Escobar, Gastón Javier Ciencias Astronómicas cosmic rays ISM: jets and outflows relativistic processes |
title_short |
Cosmic-ray production from neutron escape in microquasar jets |
title_full |
Cosmic-ray production from neutron escape in microquasar jets |
title_fullStr |
Cosmic-ray production from neutron escape in microquasar jets |
title_full_unstemmed |
Cosmic-ray production from neutron escape in microquasar jets |
title_sort |
Cosmic-ray production from neutron escape in microquasar jets |
dc.creator.none.fl_str_mv |
Escobar, Gastón Javier Pellizza, L. J. Romero, Gustavo Esteban |
author |
Escobar, Gastón Javier |
author_facet |
Escobar, Gastón Javier Pellizza, L. J. Romero, Gustavo Esteban |
author_role |
author |
author2 |
Pellizza, L. J. Romero, Gustavo Esteban |
author2_role |
author author |
dc.subject.none.fl_str_mv |
Ciencias Astronómicas cosmic rays ISM: jets and outflows relativistic processes |
topic |
Ciencias Astronómicas cosmic rays ISM: jets and outflows relativistic processes |
dc.description.none.fl_txt_mv |
The origin of Galactic cosmic rays remains a matter of debate, but supernova remnants are commonly considered to be the main place where high-energy cosmic rays are accelerated. Nevertheless, current models predict cosmic-ray spectra that do not match observations and the efficiency of the acceleration mechanism is still undetermined. On the other hand, the contribution of other kinds of sources to the Galactic cosmic-ray population is still unclear, and merits investigation. In this work we explore a novel mechanism through which microquasars might produce cosmic rays. In this scenario, microquasar jets generate relativistic neutrons, which escape and decay outside the system; protons and electrons, created when these neutrons decay, escape to the interstellar medium as cosmic rays. The most promising scenarios arise in extremely luminous systems ($L_\mathrm{jet} \sim 10^{40}\,\mathrm{erg \, s}^{-1}$), in which the fraction of jet power deposited in cosmic rays can reach $\sim 0.001$. Slow jets ($\Gamma \lesssim 2$, where $\Gamma$ is the bulk Lorentz factor) favour neutron production. The resulting cosmic-ray spectrum is similar for protons and electrons, which share the power in the ratio given by neutron decay. The spectrum peaks at roughly half the minimum energy of the relativistic protons in the jet; it is soft (spectral index $\sim 3$) above this energy, and almost flat below. Values of spectral index steeper than $2$ are possible for cosmic rays in our model and these indeed agree with those required to explain the spectral signatures of Galactic cosmic rays, although only the most extreme microquasars provide power comparable to that of a typical supernova remnant. The mechanism explored in this work may provide stronger and softer cosmic-ray sources in the early Universe, and therefore contribute to the heating and reionisation of the intergalactic medium. Instituto Argentino de Radioastronomía |
description |
The origin of Galactic cosmic rays remains a matter of debate, but supernova remnants are commonly considered to be the main place where high-energy cosmic rays are accelerated. Nevertheless, current models predict cosmic-ray spectra that do not match observations and the efficiency of the acceleration mechanism is still undetermined. On the other hand, the contribution of other kinds of sources to the Galactic cosmic-ray population is still unclear, and merits investigation. In this work we explore a novel mechanism through which microquasars might produce cosmic rays. In this scenario, microquasar jets generate relativistic neutrons, which escape and decay outside the system; protons and electrons, created when these neutrons decay, escape to the interstellar medium as cosmic rays. The most promising scenarios arise in extremely luminous systems ($L_\mathrm{jet} \sim 10^{40}\,\mathrm{erg \, s}^{-1}$), in which the fraction of jet power deposited in cosmic rays can reach $\sim 0.001$. Slow jets ($\Gamma \lesssim 2$, where $\Gamma$ is the bulk Lorentz factor) favour neutron production. The resulting cosmic-ray spectrum is similar for protons and electrons, which share the power in the ratio given by neutron decay. The spectrum peaks at roughly half the minimum energy of the relativistic protons in the jet; it is soft (spectral index $\sim 3$) above this energy, and almost flat below. Values of spectral index steeper than $2$ are possible for cosmic rays in our model and these indeed agree with those required to explain the spectral signatures of Galactic cosmic rays, although only the most extreme microquasars provide power comparable to that of a typical supernova remnant. The mechanism explored in this work may provide stronger and softer cosmic-ray sources in the early Universe, and therefore contribute to the heating and reionisation of the intergalactic medium. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-06-22 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Articulo http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://sedici.unlp.edu.ar/handle/10915/143744 |
url |
http://sedici.unlp.edu.ar/handle/10915/143744 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/issn/0004-6361 info:eu-repo/semantics/altIdentifier/issn/1432-0746 info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/202039860 info:eu-repo/semantics/altIdentifier/arxiv/2104.11975 |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International (CC BY 4.0) |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International (CC BY 4.0) |
dc.format.none.fl_str_mv |
application/pdf |
dc.source.none.fl_str_mv |
reponame:SEDICI (UNLP) instname:Universidad Nacional de La Plata instacron:UNLP |
reponame_str |
SEDICI (UNLP) |
collection |
SEDICI (UNLP) |
instname_str |
Universidad Nacional de La Plata |
instacron_str |
UNLP |
institution |
UNLP |
repository.name.fl_str_mv |
SEDICI (UNLP) - Universidad Nacional de La Plata |
repository.mail.fl_str_mv |
alira@sedici.unlp.edu.ar |
_version_ |
1844616203619794944 |
score |
13.070432 |