Flare-less long gamma-ray bursts and the properties of their massive progenitor stars

Rosalba Perna, Andrew MacFadyen

    Research output: Contribution to journalArticle

    Abstract

    While there is mounting evidence that long gamma-ray bursts (GRBs) are associated with the collapse of massive stars, the detailed structure of their pre-supernova stage is still debatable. Particularly uncertain is the degree of mixing among shells of different composition, and hence the role of magnetic torques and convection in transporting angular momentum. Here we show that early-time afterglow observations with the Swift satellite place constraints on the allowed GRB pre-supernova models. In particular, they argue against pre-supernova models in which different elemental shells are unmixed. These types of models would produce energy injections into the GRB engine on timescales between several hundreds of seconds to a few hours. Flaring activity has not been observed in a large fraction of well monitored long GRBs. Therefore, if the progenitors of long GRBs have common properties, then the lack of flares indicates that the massive stars which produce GRBs are mostly well mixed, as expected in low-metallicity, rapidly rotating massive stars.

    Original languageEnglish (US)
    JournalAstrophysical Journal Letters
    Volume710
    Issue number2 PART 2
    DOIs
    StatePublished - 2010

    Fingerprint

    massive stars
    gamma ray bursts
    flares
    shell
    supernovae
    common property resource
    torque
    angular momentum
    engine
    convection
    timescale
    mounting
    afterglows
    metallicity
    energy
    engines
    injection

    Keywords

    • Accretion, accretion disks
    • Black hole physics
    • Gamma-ray burst: general
    • X-rays: general

    ASJC Scopus subject areas

    • Space and Planetary Science
    • Astronomy and Astrophysics

    Cite this

    Flare-less long gamma-ray bursts and the properties of their massive progenitor stars. / Perna, Rosalba; MacFadyen, Andrew.

    In: Astrophysical Journal Letters, Vol. 710, No. 2 PART 2, 2010.

    Research output: Contribution to journalArticle

    Perna, Rosalba ; MacFadyen, Andrew. / Flare-less long gamma-ray bursts and the properties of their massive progenitor stars. In: Astrophysical Journal Letters. 2010 ; Vol. 710, No. 2 PART 2.
    @article{9a5115e8589146cc864841ce10738810,
    title = "Flare-less long gamma-ray bursts and the properties of their massive progenitor stars",
    abstract = "While there is mounting evidence that long gamma-ray bursts (GRBs) are associated with the collapse of massive stars, the detailed structure of their pre-supernova stage is still debatable. Particularly uncertain is the degree of mixing among shells of different composition, and hence the role of magnetic torques and convection in transporting angular momentum. Here we show that early-time afterglow observations with the Swift satellite place constraints on the allowed GRB pre-supernova models. In particular, they argue against pre-supernova models in which different elemental shells are unmixed. These types of models would produce energy injections into the GRB engine on timescales between several hundreds of seconds to a few hours. Flaring activity has not been observed in a large fraction of well monitored long GRBs. Therefore, if the progenitors of long GRBs have common properties, then the lack of flares indicates that the massive stars which produce GRBs are mostly well mixed, as expected in low-metallicity, rapidly rotating massive stars.",
    keywords = "Accretion, accretion disks, Black hole physics, Gamma-ray burst: general, X-rays: general",
    author = "Rosalba Perna and Andrew MacFadyen",
    year = "2010",
    doi = "10.1088/2041-8205/710/2/L103",
    language = "English (US)",
    volume = "710",
    journal = "Astrophysical Journal Letters",
    issn = "2041-8205",
    publisher = "IOP Publishing Ltd.",
    number = "2 PART 2",

    }

    TY - JOUR

    T1 - Flare-less long gamma-ray bursts and the properties of their massive progenitor stars

    AU - Perna, Rosalba

    AU - MacFadyen, Andrew

    PY - 2010

    Y1 - 2010

    N2 - While there is mounting evidence that long gamma-ray bursts (GRBs) are associated with the collapse of massive stars, the detailed structure of their pre-supernova stage is still debatable. Particularly uncertain is the degree of mixing among shells of different composition, and hence the role of magnetic torques and convection in transporting angular momentum. Here we show that early-time afterglow observations with the Swift satellite place constraints on the allowed GRB pre-supernova models. In particular, they argue against pre-supernova models in which different elemental shells are unmixed. These types of models would produce energy injections into the GRB engine on timescales between several hundreds of seconds to a few hours. Flaring activity has not been observed in a large fraction of well monitored long GRBs. Therefore, if the progenitors of long GRBs have common properties, then the lack of flares indicates that the massive stars which produce GRBs are mostly well mixed, as expected in low-metallicity, rapidly rotating massive stars.

    AB - While there is mounting evidence that long gamma-ray bursts (GRBs) are associated with the collapse of massive stars, the detailed structure of their pre-supernova stage is still debatable. Particularly uncertain is the degree of mixing among shells of different composition, and hence the role of magnetic torques and convection in transporting angular momentum. Here we show that early-time afterglow observations with the Swift satellite place constraints on the allowed GRB pre-supernova models. In particular, they argue against pre-supernova models in which different elemental shells are unmixed. These types of models would produce energy injections into the GRB engine on timescales between several hundreds of seconds to a few hours. Flaring activity has not been observed in a large fraction of well monitored long GRBs. Therefore, if the progenitors of long GRBs have common properties, then the lack of flares indicates that the massive stars which produce GRBs are mostly well mixed, as expected in low-metallicity, rapidly rotating massive stars.

    KW - Accretion, accretion disks

    KW - Black hole physics

    KW - Gamma-ray burst: general

    KW - X-rays: general

    UR - http://www.scopus.com/inward/record.url?scp=77949493641&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=77949493641&partnerID=8YFLogxK

    U2 - 10.1088/2041-8205/710/2/L103

    DO - 10.1088/2041-8205/710/2/L103

    M3 - Article

    VL - 710

    JO - Astrophysical Journal Letters

    JF - Astrophysical Journal Letters

    SN - 2041-8205

    IS - 2 PART 2

    ER -