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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').
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"

2380 results found.

  1. GRB 260608A: Fermi GRB Observation
  2. GRB 260604C: AstroSat CZTI detection
  3. GRB 260604C: SVOM/ECLAIRs refined analysis
  4. GRB 260608A: SVOM/ECLAIRs refined analysis
  5. GRB 260604C: further SAO RAS optical observations
  6. GRB 260604C: SVOM/COLIBRÍ (FM-GFT) colour evolution and confirmation of the late rebrightening
  7. GRB 260604C: SVOM/C-GFT upper limit
  8. GRB 260608A: SVOM detection of a burst
  9. GRB 260604C: GRANDMA further observations
  10. GRB 260604A: SVOM/GRM detection
  11. GRB 260604C: OPD1.6m - GRANDMA observations - detection
  12. GRB 260604C: GECAM-B observation
  13. GRB 260604C: 6 GHz VLA observations
  14. GRB 260604C: SAO RAS optical observations
  15. GRB 260604C: GRANDMA observations
  16. GRB 260604B: SVOM/GRM detection
  17. GRB 260605A: Insight-HXMT/HE detection
  18. GRB260603A: SVOM/ECLAIRs refined analysis
  19. GRB 260604C: LCO optical upper limit
  20. GRB 260604C: GOTO detections of the optical afterglow
  21. GRB 260604C: Kilonova-Catcher optical afterglow detection
  22. GRB 260604C: SVOM/COLIBRÍ (FM-GFT) optical observations
  23. GRB 260604C: Jinshan optical observations
  24. GRB 260604C: Fermi GBM Observation
  25. GRB 260604C: LAST detection of optical counterpart candidate
  26. SVOM GRB260604.85: Global MASTER-Net observations report
  27. GRB 260604C: SVOM detection of a long burst
  28. GRB 260515A: SVOM/VT optical detection at about 18 days post trigger
  29. GRB 260603A: NOT optical observations
  30. GRB 260601A: CALET Gamma-Ray Burst Monitor detection
  31. GRB 260603A: EP-FXT follow-up observation
  32. GRB 260603A: Kilonova-Catcher optical upper limit
  33. GRB 260603A: SVOM/VT optical observations
  34. GRB 260603A: SVOM/COLIBRÍ (FM-GFT) photometric redshift z = 3.57
  35. EP260602a: SVOM/VT optical magnitudes correction
  36. GRB 260601A: SVOM/GRM observation of a short burst
  37. GRB 260603A: SVOM/COLIBRÍ (GFT-FM) optical counterpart candidate
  38. SVOM GRB260603.23: Global MASTER-Net observations report
  39. GRB 260603A: SVOM detection of a burst
  40. EP260602a: SVOM/VT optical candidate
  41. GRB 260601B/EP260601a: SVOM/VT optical observations
  42. GRB 260530C: SVOM/ECLAIRs detection of a burst through on-ground search
  43. GRB 260518B: SVOM/ECLAIRs detection of a soft burst possibly associated with EP 260518a and AT 2026ndp
  44. GRB 260530B: SVOM/GRM detection of a possible bright short GRB
  45. EP260526a: SVOM/VT optical upper limits
  46. EP260527a: SVOM/VT optical observation
  47. GRB 260524A: SVOM/ECLAIRs detection of a burst through on-ground search
  48. GRB 260522B: NuSTAR detection of prompt emission
  49. GRB 260519C: SVOM/GRM observation
  50. GRB 260511A: iTelescope T-75 optical detection
  51. GRB 260520B: SVOM/GRM observation
  52. GRB 260411B: TERI Gamma-ray detection
  53. GRB 260225D: TERI Gamma-ray detection
  54. GRB 260428A: TERI Gamma-ray detection
  55. GRB 260509A: SVOM/ECLAIRs refined analysis
  56. GRB 260519C: NuSTAR detection of prompt emission
  57. GRB 260516D: SVOM/ECLAIRs refined analysis
  58. GRB 260515A: SVOM/ECLAIRs refined analysis
  59. GRB 260421B: radio detection with the VLA
  60. GRID detection of GRB 260511A
  61. GRB 260516D: EP-FXT follow-up observation
  62. GRB 260516D: GOTO optical counterpart detection
  63. GRB 260516D: LCO optical observations
  64. GRB 260516D: SVOM/COLIBRÍ (FM-GFT) optical observations
  65. GRB 260516D: SVOM/VT optical bright candidate
  66. GRB 260516D: FRAM-ORM optical limit
  67. SVOM GRB260516D: Global MASTER-Net observations report
  68. GRB 260516D: SVOM possible detection of a burst
  69. Konus-Wind detection of GRB 260515A
  70. GRB 260515A: LCO optical counterpart detection
  71. GRB 260515A: SVOM/COLIBRÍ (FM-GFT) optical observations
  72. GRB 260515A: EP-FXT follow-up observation
  73. EP260514a: TRT optical counterpart candidate
  74. EP260514a: SVOM/VT optical candidate
  75. GRB 260515A: SVOM/VT optical observations
  76. GRB 260515A: OHP/T193 optical observations
  77. GRB 260515A: LCO optical observations
  78. SVOM GRB 260515A: Global MASTER-Net observations report
  79. GRB 260515A: NOT optical observations.
  80. SVOM GRB 260515A: MASTER OT J151044.43+243321.7 optical counterpart detection
  81. GRB 260515A: SVOM/VT optical candidate from VHF data
  82. GRB 260515A: JinShan optical counterpart candidate
  83. GRB 260515A: SVOM detection of a burst
  84. GRB 260510C: Glowbug gamma-ray detection
  85. GRB 260511B: NOT optical observations
  86. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  87. GRB 260511B: Mephisto multi-band optical followup
  88. GRB 260511B: further SAO RAS optical observations
  89. GRB 260509A: SVOM/VT optical observations
  90. Konus-Wind detection of GRB 260511B
  91. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  92. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  93. GRB 260511A: Glowbug gamma-ray detection
  94. Konus-Wind detection of GRB 260511A
  95. MASS-Cube (GRID 2.0) detection of GRB 260511A
  96. GRB 260511B: SAO RAS optical observations
  97. GRB 260511B: FRAM-ORM optical detection
  98. GRB 260511A: EP-FXT follow-up observation
  99. GRB 260511B: EP-FXT follow-up observation
  100. GRB 260511B: LCO optical counterpart detection

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