Probing the interstellar medium toward GRB 221009A through X-ray dust scattering

Znanstveni rad - Izvorni znanstveni rad

• Autor: Beatrice Vaia
• Autor: Željka Bošnjak
• Autor: Andrea Bracco
• Autor: Sergio Campana
• Autor: Paolo Esposito
• Autor: Vibor Jelić
• Autor: Andrea Sacchi
• Autor: Andrea Tiengo
• Autorova ustanova: Sveučilište u Zagrebu; Fakultet elektrotehnike i računarstva
• Znanstveno / umjetničko područje, polje i grana: PRIRODNE ZNANOSTI; Fizika; Astronomija i astrofizika

Sažetak (engleski)

The observation of 21 X-ray dust-scattering rings around the extraordinarily bright gamma-ray burst (GRB) 221009A provides a unique opportunity to study the interstellar medium (ISM) through which the X-ray radiation traveled in our Galaxy and, by extension, in the host galaxy as well. In particular, since the ring intensity and radius at a given time depend on the amount of dust and on its distance, respectively, XMM-Newton and Swift images allowed us to map the ISM around the direction of the... Više GRB with better resolution than in the existing optical- and infrared-based 3D dust maps, both in the plane of the sky (a few arcminutes) and along the line of sight (from≃1 pc for dust clouds within 1 kpc to≃100 pc for structures at distances larger than 10 kpc). As a consequence, we could revise prior estimates of the GRB soft X-ray fluence, obtaining a∼35% lower value, which, however, still indicates a substantial excess with respect to the extrapolation of the spectral models constrained by hard X-ray observations. Additionally, we detect significant spectral variability in two azimuthal sectors of the X-ray rings, which can be fully attributed to different Galactic absorption in these two directions. The comparison of the total hydrogen column density inferred from spectral fitting, with the Galactic contribution derived from the intensity of the X-ray rings, in the same sectors allowed us to more robustly constrain the absorption in the host galaxy to N_{H,z=0.151} = (3.7 ±0.3) ×10^21 cm^{−2}. This result is relevant not only for characterizing the ISM of the host galaxy and understanding how the GRB radiation might have affected it, but also for modeling the broadband spectrum of the GRB afterglow and constraining the properties of a possible underlying supernova. Sakrij dio sažetka

• Ključne riječi (engleski): dust, extinction; X-rays: ISM; gamma-ray burst: individual: GRB 221009A
• Jezik: engleski
• Vrsta publikacije: Znanstveni rad - Izvorni znanstveni rad
• Status objave: Objavljen
• Vrsta recenzije: Recenziran - međunarodna recenzija
• Verzija publikacije: Objavljena verzija rada (izdavačev PDF)
• Naslov časopisa: Astronomy and Astrophysics
• Brojčani podaci: vol. 696, A9
• BPC: 0 EUR
• p-ISSN: 2329-1273
• e-ISSN: 2329-1265
• DOI: https://doi.org/10.1051/0004-6361/202453158
• URN:NBN: urn:nbn:hr:168:143534
• Datum objave publikacije: 2025-03-25
• URL dokumenta: https://www.aanda.org/articles/aa/full_html/2025/04/aa53158-24/aa53158-24.html
• Vrsta resursa: Tekst
• Prava pristupa: Otvoreni pristup
• Datum i vrijeme pohrane: 2025-03-28 15:40:38