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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

69 results found.

  1. Fermi GRB 250510C: Global MASTER-Net observations report
  2. Fermi trigger No 723149952: Global MASTER-Net observations report
  3. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  4. Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
  5. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  6. Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552
  7. Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
  8. Fermi GBM Detection of possible burst from AXP 4U 0142+61
  9. AXP CXOU J164710.2-455216: Fermi GBM observation
  10. Swift Trigger AXP CXOU J164710.2-455216: MASTER-OAFA observations
  11. Swift Trigger on AXP CXOU J164710.2-455216
  12. Trigger 706396: Swift detection of a short burst from PSR 1119-6127
  13. GRB 150301A: Fermi GBM observation
  14. GRB 140705A / SGR 1935+2154: Probable association with supernova remnant G57.2+0.8
  15. IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
  16. Fermi/GBM observation of the Soft Gamma Repeater SGR J1550-5418
  17. Trigger 558399: Swift detection of the Soft Gamma Repeater AXP 1E1547.0-5408
  18. GRB 130604A: Swift/UVOT Upper Limits
  19. AXP 4U 1042+61: Mondy optical observations
  20. AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
  21. Swift detection of an SGR burst from AXP 4U 0142+61
  22. AXP 4U 0142+61: Fermi GBM detection
  23. AXP 4U 0142+61: Swift-BAT refined analysis
  24. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  25. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  26. Swift-BAT refined analysis of trigger 421262
  27. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  28. GRB100316A: Swift/UVOT Upper Limits
  29. A bright burst from AXP 1E 1547.0-5408/SGR J1550-5418
  30. ATCA observation of SGR J1550-5418
  31. Konus-RF catches first GRB and SGR bursts
  32. SGR J1550-5418
  33. Ongoing activity of AXP/SGR 1E1547.0-5408
  34. SGR activity seen by BAT during ICSP Ionospheric Events
  35. Detailed lightcurves of ICSP VLF Observation of SGR/AXP 1E1547.0-5408
  36. Fermi Gamma-ray Burst Monitor trigger 255729682 is not a GRB
  37. ICSP VLF observation of the signatures of SGR/AXP 1E1547.0-5408 bursts
  38. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  39. IBAS Alert N. 5442 is not a GRB
  40. Suzaku ToO Observation of AXP 1E 1547.0-5408
  41. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  42. AXP 1E1547.0-5408: RHESSI observations up to 400 keV
  43. Konus-Wind detection of very bright SGR-like burst on January 25, 2009
  44. 1E1547.0-5408: Swift detection of dust halo
  45. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  46. AXP 1E1547.0-5408: long bursts with INTEGRAL SPI-ACS
  47. Swift-BAT trigger 340734 is not a GRB
  48. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  49. AXP 1E1547.0-5408: INTEGRAL SPI-ACS confirms activity increase
  50. AXP 1E1547.0-5408: Fermi GBM observations
  51. Trigger 340734: Swift detection of a possible short burst
  52. AXP 1E1547.0-5408 activity with SGR bursts
  53. Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
  54. INTEGRAL ToO observation of the AXP 1E 1547.0-5408
  55. AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
  56. AXP 1E1547.0-5408: Swift-XRT Team refined analysis
  57. Swift-BAT refined analysis of AXP 1E1547.0-5408 (Trigger 330353)
  58. AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
  59. SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
  60. Swift discovery of a new Soft Gamma Repeater SGR 1550-5418
  61. Trigger 330353: Swift detection of a Galactic short soft burst
  62. GRB 071017: a SHORT GRB detected by INTEGRAL
  63. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  64. IPN detection of continued activity from SGR1806-20
  65. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  66. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  67. AXP 1E2259+586: quasi-simultaneous optical observation
  68. AXP 1E2259+586 optical observations
  69. SGR-like Bursts from the AXP 1E 2259+586

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