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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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"

41975 results found.

  1. Fermi trigger No 772128434: Global MASTER-Net observations report
  2. GRB 250620B: Fermi GBM Final Real-time Localization
  3. GRB 250620A: Fermi GBM Final Real-time Localization
  4. EP-WXT trigger 01709179036: a new outburst of GRS 1739-278
  5. GRB 250617B: Nickel telescope optical observations
  6. GRB 250619B: Fermi GBM Final Real-time Localization
  7. Fermi trigger No 772058337: Global MASTER-Net observations report
  8. GRB 250615A: Kilonova-Catcher optical upper limits
  9. GRB 250619A: Fermi GBM Final Real-time Localization
  10. GRB 250617B: Assy AZT-20 Optical Observations
  11. GRB 250612A / Swift J1643.6−3854: Swift-BAT refined analysis
  12. Fermi GRB 250617A: Global MASTER-Net observations report
  13. GRB 250615A/EP250615a: FTW optical and NIR observations
  14. sb25061218/SVOM: OHP/T120 and OHP/T193 optical imaging and spectroscopic observations
  15. GRB 250617B: Swift/UVOT Detection
  16. GRB 250617B: Kilonova-Catcher optical afterglow detection
  17. GRB 250617B: VLT/X-shooter spectroscopic redshift z = 1.396
  18. GRB 250617B: COLIBRÍ optical observations
  19. GRB 250617B: NOT NIR observations of the afterglow
  20. GRB 250617B: Swift-XRT refined Analysis
  21. GRB 250617B: SVOM/VT optical observation
  22. GRB 250617B: NUTTelA-TAO early time optical observations
  23. Fermi trigger No 771886893: Global MASTER-Net observations report
  24. Swift GRB 250617B: Global MASTER-Net observations report
  25. GRB 250617B: GOTO optical upper limit
  26. GRB 250617B: Enhanced Swift-XRT position
  27. GRB 250617B: Fermi GBM Observation
  28. GRB 250615A: Swift-BAT refined analysis
  29. The EP-WXT trigger 01709178990 is likely a flaring star
  30. GRB 250617B: Fermi GBM Final Localization
  31. GRB 250617B: Ondrejov D50 optical afterglow detection
  32. GRB 250617B: SAO RAS optical observations
  33. GRB 250617B: Swift detection of a burst with an optical counterpart
  34. GRB 250615A: Calapai Observatory, Massa S. Giorgio (Messina), upper limit
  35. GRB 250617A: Fermi GBM Final Real-time Localization
  36. IPN triangulation of GRB 250612C (short/hard)
  37. EP#01709178975: Swift-XRT counterpart detection
  38. EP-WXT trigger 01709178975: GOTO optical upper limit
  39. The EP-WXT trigger 01709178975 is likely a flaring star
  40. Konus-Wind detection of GRB 250615A / EP250615a
  41. GRB 250615A / EP250615a: AstroSat CZTI detection
  42. SVOM sb25061207: AbAO AS-32 Optical Upper Limit
  43. GRB 250615A: COLIBRÍ optical upper limit
  44. GRB 250615A: DDOTI Optical Upper Limit
  45. GRB 250615A: Swift/UVOT Upper Limits
  46. Konus-Wind detection of GRB 250612C (short/hard with extended emission)
  47. GRB 250615A: Swift-XRT refined Analysis
  48. sb25061207/SVOM: T120 OHP optical upper limit
  49. EP250615a/GRB 250615A: EP-WXT detection of a fast X-ray transient
  50. Fermi trigger No 771752663: Global MASTER-Net observations report
  51. The EP-WXT trigger 01709178875 is likely a flaring star
  52. GRB 250615A: Enhanced Swift-XRT position
  53. GRB 250615A: Prompt enhanced Swift-XRT position
  54. GRB 250615A: Swift detection of a burst
  55. Swift GRB 250615A: Global MASTER-Net observations report
  56. Fermi trigger No 771718064: Global MASTER-Net observations report
  57. GRID detection of GRB 250612C
  58. sb25061207: Mephisto optical upper limits
  59. IceCube alert 141029_8144692 retraction
  60. GRB 250614A: Fermi GBM Final Real-time Localization
  61. EP250612a / GRB 250612B: NOT optical observations of the afterglow candidate
  62. sb25061218: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  63. sb25061207: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  64. Fermi trigger No 771494087: Global MASTER-Net observations report
  65. sb25061218: Swift-XRT observations
  66. EP250612a: refined analysis of the EP-WXT and EP-FXT observations
  67. GRB 250610B: J band upper limit by SYSU 80cm infrared telescope
  68. sb25061207: EP-FXT follow-up observation and afterglow candidate
  69. GRB 250612B: Fermi GBM Observation
  70. Fermi trigger No 771424081: Global MASTER-Net observations report
  71. EP250612a: Global MASTER-Net observations report
  72. GRB 250612C: Fermi GBM Observation
  73. sb25061218: SVOM detection of a X-ray transient
  74. sb25061207: Swift-XRT observations
  75. EP250612a/GRB 250612B: JinShan optical upper limit
  76. EP 250612a: AST3-3 Yaoan Optical Observation
  77. GRB 250612C: SVOM/GRM observation an intermedium duration burst
  78. sb25061207: SVOM/VT optical counterpart
  79. GRB 250612C: BALROG localization (Fermi Trigger 771432801 / GRB 250612620)
  80. GRB 250610B: Swift-XRT refined Analysis
  81. GRB 250612C: Fermi GBM Final Real-time Localization
  82. EP250610a: Upper limit from Fermi-GBM Observations
  83. GRB 250612B (250612519/771424081): Fermi GBM Final Localization
  84. GRB 250612B: BALROG localization (Fermi Trigger 771424081 / GRB 250612519)
  85. EP250612a: Einstein Probe detection of an X-ray transient
  86. GRB 250610B: Liverpool Telescope continued monitoring
  87. GRB 250610B: MISTRAL/T193 and T120 OHP further observations
  88. sb25061207: SVOM detection of a X-ray transient
  89. EP250610a: continuous follow-up observations with EP-FXT
  90. GRB 250610B - SVOM/ECLAIRs refined analysis
  91. GRB 250612A: Swift detection of a burst or new Galactic transient Swift J1643.6-3854
  92. Swift GRB250612.04: Global MASTER-Net observations report
  93. Fermi GBM Sub-Threshold Detection of GRB 250610B
  94. GRB 250610B: Swift/UVOT Detection
  95. EP250610A: Swift/UVOT Upper limits
  96. GRB 250610B: SVOM/COLIBRÍ (FM-GFT) optical observations
  97. EP250610a: TNG NIR upper limit
  98. GRB 250610B: REM optical/NIR observations
  99. EP250610a: Liverpool Telescope optical upper limits
  100. GRB 250610B: SVOM/VT optical shallow decay

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