{
  "eventId": "GRB 260909A",
  "createdOn": 1789583292385,
  "submittedHow": "email",
  "subject": "GRB 260909A: NOEMA detection",
  "body": "A. de Ugarte Postigo (LAM), M. Bremer (IRAM), C. C. Thoene (AbAO), S. Basa (LAM), S. Geier (GTC), L. Izzo (INAF/OACN and DARK/NBI), A. Martin-Carrillo (UCD), M. Michalowski (AOI-AMU), D. A. Perley (LJMU), D. B. Malesani (DAWN/NBI and Radboud), B. Schneider (LAM), N.R. Tanvir (U. Leicester), L. Resmi (IIST), K. Misra (ARIES) report:\n\nWe observed the field of GRB 260909A (Saccardi et al. GCN 45534, Wang et al. GCN 45538, Brunet et al. GCN 45553) with the NOEMA interferometer, located at Plateau de Bure (France). Observations started on the 14th September 2026 at 22:55 UT (5.48 days after the GRB) at 81 and 96 GHz simultaneously. An object is clearly detected consistent with the position of the X-ray afterglow (Mao et al., GCN 45543), at a combined flux density of ~0.4 mJy. . The spectral slope between our two observing bands is beta ~ -1.3 +/- 0.6 (where F_nu is proportional to nu^beta). Although this is a rather steep value for this observing time, the large uncertainties make it compatible with a normal spectral slope of a GRB afterglow, where the peak frequency falls at lower frequencies.\n\nThe best coordinates of the source are (J2000):\n\nR.A. = 00:52:08.462\nDec. = +24:11:47.12\n\nWith an uncertainty of ~ 0.2 \"\n\nWe acknowledge excellent support from the IRAM staff. Based on observations carried out under project number S26DT with the IRAM NOEMA Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain).\n\n",
  "circularId": 45597,
  "submitter": "Antonio de Ugarte Postigo at LAM, CNRS <adeugartepostigo@gmail.com>"
}