The First JWST Spectrum of a GRB Afterglow: No Bright Supernova in Observations of the Brightest GRB of all Time, GRB 221009A

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F23%3A00571489" target="_blank" >RIV/67985815:_____/23:00571489 - isvavai.cz</a>

Result on the web

<a href="https://hdl.handle.net/11104/0342981" target="_blank" >https://hdl.handle.net/11104/0342981</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/2041-8213/acc2c1" target="_blank" >10.3847/2041-8213/acc2c1</a>

Result language

angličtina

Original language name

The First JWST Spectrum of a GRB Afterglow: No Bright Supernova in Observations of the Brightest GRB of all Time, GRB 221009A

Original language description

We present James Webb Space Telescope (JWST) and Hubble Space Telescope (HST) observations of the afterglow of GRB 221009A, the brightest gamma-ray burst (GRB) ever observed. This includes the first mid-IR spectra of any GRB, obtained with JWST/Near Infrared Spectrograph (0.6-5.5 micron) and Mid-Infrared Instrument (5-12 micron), 12 days after the burst. Assuming that the intrinsic spectral slope is a single power law, with F ( nu ) proportional to nu (-beta ), we obtain beta approximate to 0.35, modified by substantial dust extinction with A ( V ) = 4.9. This suggests extinction above the notional Galactic value, possibly due to patchy extinction within the Milky Way or dust in the GRB host galaxy. It further implies that the X-ray and optical/IR regimes are not on the same segment of the synchrotron spectrum of the afterglow. If the cooling break lies between the X-ray and optical/IR, then the temporal decay rates would only match a post-jet-break model, with electron index p < 2, and with the jet expanding into a uniform ISM medium. The shape of the JWST spectrum is near-identical in the optical/near-IR to X-SHOOTER spectroscopy obtained at 0.5 days and to later time observations with HST. The lack of spectral evolution suggests that any accompanying supernova (SN) is either substantially fainter or bluer than SN 1998bw, the proto-type GRB-SN. Our HST observations also reveal a disk-like host galaxy, viewed close to edge-on, that further complicates the isolation of any SN component. The host galaxy appears rather typical among long-GRB hosts and suggests that the extreme properties of GRB 221009A are not directly tied to its galaxy-scale environment.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astrophysical Journal Letters

ISSN

2041-8205

e-ISSN

2041-8213

Volume of the periodical

946

Issue of the periodical within the volume

1

Country of publishing house

US - UNITED STATES

Number of pages

14

Pages from-to

L28

UT code for WoS article

000966888100001

EID of the result in the Scopus database

2-s2.0-85151503468