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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"

36013 results found.

  1. GRB 251122A/EP251122a: Additional, deeper LCO optical r band upper limit
  2. GRB 251122A / EP251122a: LCO optical upper limits
  3. EP251122a / GRB 251122A: optical counterpart candidate with Kinder observations
  4. GRB 251122A/EP251122a: SVOM/C-GFT upper limit
  5. GRB 251122A / EP251122a: SVOM detection of a long burst
  6. GRB 251121A: Swift/BAT-GUANO localization skymap of a short burst
  7. GRB 251121A: Glowbug gamma-ray detection of a likely short burst
  8. EP251118a: Xinglong-2.16m optical observation
  9. GRB 251115A: Fermi GBM Observation
  10. GRB 251121A: Fermi GBM Final Real-time Localization
  11. Fermi Gamma-ray Burst Monitor trigger 785388351 / 251121143 is not a GRB
  12. GRB 251118A: Swift/UVOT Detection
  13. EP251118a / GRB 251118C: SAO RAS optical observations
  14. GRB 251118A: Glowbug gamma-ray detection
  15. GRB 251118A: Fermi GBM Observation
  16. GRB 251118A: Swift-XRT afterglow detection
  17. GRB 251103A: SVOM/ECLAIRs and SVOM/GRM joint refined analysis
  18. GRB 251118A: GECAM-B detection
  19. EP251118a / GRB 251118C: SVOM/VT optical observation
  20. GRB 251118A: NuSTAR detection of bright prompt emission
  21. EP251118a / GRB 251118C: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at CTIO
  22. GRB 251116C: NOT optical observations
  23. GRB 251118C: Glowbug gamma-ray detection of the fast X-ray transient EP251118A
  24. GRB 251118C: Swift/BAT rates detection of a burst with a possible association with EP 251118A
  25. GRB 251018A: FRAM-Auger optical detection
  26. GRB 251117A: Swift-XRT observations
  27. EP251118A / GRB 251118C : MASTER optical counterpart observations
  28. GRB 251118C: SVOM/GRM observation of a possible gamma-ray counterpart of EP251118a
  29. Konus-Wind detection of GRB 251118C (EP251118a)
  30. GRB 251117A: Insight-HXMT/HE detection
  31. GRB 251119A: SVOM trigger sb25111901 is not a GRB
  32. GRB 251116D: SVOM/GRM observation of a long GRB
  33. GRB 251119A: SVOM detection of a possible burst
  34. EP251118a: NOT spectroscopic redshift of z = 1.216
  35. GRB 251118A: Fermi-LAT detection
  36. GRB 251118A: Swift ToO observations
  37. Fermi GRB 251118B: Global MASTER-Net observations report
  38. GRB 251118B: Fermi GBM Final Real-time Localization
  39. LIGO/Virgo/KAGRA S251112cm: Upper limits from Glowbug gamma-ray observations
  40. GRB 251118A: BALROG localization (Fermi Trigger 785190695 / GRB 251118855)
  41. GRB 251117A: FTW Observations of Swift candidate X-ray sources
  42. GRB 251118A: Fermi GBM Final Real-time Localization
  43. GRB 251116C: SVOM/ECLAIRs refined analysis
  44. GRB 251116B: SVOM/ECLAIRs refined analysis
  45. GRB 251117A: AstroSat CZTI detection
  46. GRB 251114B: Insight-HXMT/HE detection
  47. GRB 251114B: GECAM-B detection of a short burst
  48. GRB 251117A: Fermi GBM observation
  49. GRB 251013C: Koshka, SAO RAS, Mondy, and CrAO optical observations, possible SN detection
  50. GRB 251116D: Insight-HXMT/HE detection
  51. GRB 251115A: Swift-XRT observations
  52. GRB 251117A: Swift/BAT-GUANO localization skymap of a short burst
  53. GRB 251117A: SVOM/GRM observation of a short burst
  54. GRB 251117A: Tiled Swift observations
  55. GRB 251117A: Fermi-LAT detection
  56. GRB 251116C: Swift/BAT arcminute localization of a burst
  57. GRB 251116B: SVOM/VT optical upper limit
  58. GRB 251116C: Swift-XRT observations
  59. GRB 251117A: Fermi GBM Final Localization Correction
  60. GRB 251116D: Glowbug gamma-ray detection
  61. EP251023a: Assy AZT-20 optical observations
  62. EP251023a: UAFO and AbAO optical observations
  63. GRB 251116D: AstroSat CZTI detection
  64. The EP-WXT trigger 01709247588: more evidence of flaring star from Mondy optical observations
  65. GRB 251116C: SVOM/VT optical upper limit
  66. GRB 251025B: further Mondy optical observations
  67. GRB 251111A: Mondy optical upper limit
  68. GRB 251116B: EP-FXT follow-up observation
  69. GRB 251116B: LCO optical upper limits
  70. GRB 251116C: LCO optical upper limits
  71. GRB 251116C: SVOM detection of a burst
  72. GRB 251116B: SVOM detection of a burst
  73. GRB 251116A: Fermi GBM Final Real-time Localization
  74. GRB 251115A: Tiled Swift observations
  75. GRB 251115A: Fermi-LAT detection
  76. GRB 251013C: joint SVOM/ECLAIRs-GRM refined analysis
  77. Fermi GRB 251115A: Global MASTER-Net observations report
  78. GRB 251115A: Fermi GBM Final Real-time Localization
  79. GRB 251113A: Glowbug gamma-ray detection
  80. GRB 251113A: AstroSat CZTI detection
  81. GRB 251114B: Fermi GBM Final Real-time Localization
  82. GRB 251112A: Swift-BAT refined analysis
  83. Konus-Wind detection of GRB 251108C
  84. Konus-Wind detection of GRB 251103A
  85. IPN triangulation of GRB 251108C
  86. Fermi GRB 251114A: Global MASTER-Net observations report
  87. GRB 251114A: Fermi GBM Final Real-time Localization
  88. Fermi GRB 251113A: Global MASTER-Net observations report
  89. GRB 251113A: BALROG localization (Fermi Trigger 784748255 / GRB 251113734)
  90. GRB 251113A: Fermi GBM Final Real-time Localization
  91. GRB 251111A: SVOM/ECLAIRs refined analysis
  92. GRB 251025B: SVOM/ECLAIRs refined analysis
  93. Fermi Gamma-ray Burst Monitor trigger 784717756/251113381 is not a GRB
  94. GRB 251112A: Swift/UVOT Upper Limits
  95. GRB 251112A: Swift-XRT refined Analysis
  96. GRB 251108C: AstroSat CZTI detection
  97. GRB 251112B: MAXI/GSC detection
  98. Fermi Gamma-ray Burst Monitor trigger 784687703/251113034 is not a GRB
  99. Fermi Gamma-ray Burst Monitor trigger 784687099/251113027 is not a GRB
  100. GRB 251108B: Glowbug gamma-ray detection

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