Abstract
We present the discovery of the first millimeter afterglow of a short-duration γ-ray burst (SGRB) and the first confirmed afterglow of an SGRB localized by the GUANO system on Swift. Our Atacama Large Millimeter/Sub-millimeter Array (ALMA) detection of SGRB 211106A establishes an origin in a faint host galaxy detected in Hubble Space Telescope imaging at 0.7 ≲ z ≲ 1.4. From the lack of a detectable optical afterglow, coupled with the bright millimeter counterpart, we infer a high extinction, A V ≳ 2.6 mag along the line of sight, making this one of the most highly dust-extincted SGRBs known to date. The millimeter-band light curve captures the passage of the synchrotron peak from the afterglow forward shock and reveals a jet break at t jet = 29.2 − 4.0 + 4.5 days. For a presumed redshift of z = 1, we infer an opening angle, θ jet = (15.°5 ± 1.°4), and beaming-corrected kinetic energy of log ( E K / erg ) = 51.8 ± 0.3 , making this one of the widest and most energetic SGRB jets known to date. Combining all published millimeter-band upper limits in conjunction with the energetics for a large sample of SGRBs, we find that energetic outflows in high-density environments are more likely to have detectable millimeter counterparts. Concerted afterglow searches with ALMA should yield detection fractions of 24%-40% on timescales of ≳2 days at rates of ≈0.8-1.6 per year, outpacing the historical discovery rate of SGRB centimeter-band afterglows.
| Original language | English (US) |
|---|---|
| Article number | L11 |
| Journal | Astrophysical Journal Letters |
| Volume | 935 |
| Issue number | 1 |
| DOIs | |
| State | Published - Aug 1 2022 |
Funding
T.L. acknowledges support from the Radboud Excellence Initiative. The Fong Group at Northwestern acknowledges support from the National Science Foundation under grants AST-1814782, AST-1909358, and CAREER grant AST-2047919. W.F. gratefully acknowledges support from the David and Lucile Packard Foundation. E.B. acknowledges support from NSF and NASA grants. P.V. acknowledges support from NASA grant NNM11AA01A. S.B. is supported by a Dutch Research Council (NWO) Veni Fellowship (VI.Veni.212.058). Support for this work was provided by the National Aeronautics and Space Administration through Chandra Award Numbers GO1-22059X and DD1-22132X issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060. The scientific results reported in this article are based in part on observations made by the Chandra X-ray Observatory. This work is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This research is based on observations made with the NASA/ESA Hubble Space Telescope obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program 16303. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2019.1.00863.T. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. We acknowledge the Gomeroi people as the traditional owners of the Observatory site.
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science