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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"

36367 results found.

  1. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  2. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  3. GRB 241120A: GRBAlpha detection
  4. GRB 241113B: SVOM/VT optical afterglow observations
  5. Konus-Wind detection of GRB 241117A
  6. GRB 241105A: ATCA radio detection
  7. IPN triangulation of GRB 241117A
  8. GRB 241026A: VIRT Optical Upper Limit
  9. GRB 241025A: VIRT Optical Upper Limit
  10. Konus-Wind detection of GRB 241120A
  11. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  12. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  13. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  14. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  15. GRB 241120A: Mondy and AbAO optical observations
  16. GRB 241113A: Possible ATCA Radio detection
  17. GRB 241120A: Fermi GBM Observation
  18. GRB 241114B: Insight-HXMT/HE detection
  19. GRB241120A: a long GRB detected by INTEGRAL
  20. GRB 241120A: Fermi GBM Final Real-time Localization
  21. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  22. GRB 241112B: Mephisto further optical observations
  23. GRB 241119A: Fermi GBM Final Real-time Localization
  24. GRB 241030A: J-band observations
  25. GRB 241115a: PRIME near-infrared upper limits
  26. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  27. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  28. GRB 241115B: Fermi GBM Observation
  29. Fermi GRB 241118A: Global MASTER-Net observations report
  30. GRB 241118A: Fermi GBM Final Real-time Localization
  31. Updates to IceCube realtime alert system for muon tracks
  32. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  33. GRB 241117A: Fermi GBM Detection
  34. Fermi GRB 241117B: Global MASTER-Net observations report
  35. GRB 241117B: Fermi GBM Final Real-time Localization
  36. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  37. Fermi GRB 241117A: Global MASTER-Net observations report
  38. GRB 241117A: Fermi GBM Final Real-time Localization
  39. GRB 241115C: Fermi GBM Observation
  40. GRB 241115A: Swift-XRT afterglow detection
  41. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  42. GRB 241115A: Mephisto upper limits
  43. GRB 241113B: Mephisto upper limits
  44. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  45. GRB 241115D / EP 241115a: SVOM/GRM observation
  46. GRB 241115A: Fermi GBM Observation
  47. GRB 241115A: LCOGT Optical Upper Limits
  48. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  49. Fermi GRB 241115B: Global MASTER-Net observations report
  50. GRB 241115B: Fermi GBM Final Real-time Localization
  51. EP241113a: No Detection in Fermi-GBM Observations
  52. Swift GRB 241115A: Global MASTER-Net observations report
  53. Fermi GRB 241115A: Global MASTER-Net observations report
  54. GRB 241115A: Swift detection of a burst
  55. GRB 241115A: Fermi GBM Final Real-time Localization
  56. GRB 241113B: KAIT Optical Afterglow Candidate
  57. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  58. GRB 241113A: Swift-BAT refined analysis
  59. GRB 241113A: PRIME near-infrared upper limits
  60. Fermi GRB 241114A: Global MASTER-Net observations report
  61. GRB 241114A: Fermi GBM Final Real-time Localization
  62. GRB 241113B: J-band upper limit from WINTER
  63. GRB 241113A: J-band observations with WINTER
  64. GRB 241030A: LCO optical observation
  65. GRB 241113B: Swift-XRT observations
  66. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  67. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  68. GRB 241113A: KAIT optical observations
  69. EP241113b/GRB 241113B: EP detection of GRB 241113B
  70. GRB 241113B: SVOM/GRM observation
  71. GRB 241113A: Swift-XRT refined Analysis
  72. GRB 241113A: Swift/UVOT Detection
  73. GRB 241113A: REM detection of the optical/NIR afterglow
  74. Konus-Wind detection of GRB 241107A (short/hard)
  75. Fermi Gamma-ray Burst Monitor trigger 753166198/241113201 is not a GRB
  76. GRB 241113B: Swift ToO observations
  77. GRB 241113A: LCO optical observations
  78. GRB 241112B: GMG Optical Upper Limit
  79. GRB 241113A: Enhanced Swift-XRT position
  80. GRB241113A: LCOGT (40-cm) optical counterpart detection
  81. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  82. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  83. GRB 241113A: Swift detection of a burst with an optical counterpart
  84. GRB 241105A: ATCA Radio Upper Limits
  85. GRB 241112B: AbAO optical upper limit
  86. GRB 241107A: GROWTH-India telescope optical upper limit
  87. Fermi GRB 241112A: Global MASTER-Net observations report
  88. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  89. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  90. GRB 241112B: Swift-XRT afterglow detection
  91. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  92. GRB 241112B: SVOM/GRM observation
  93. GRB 241112B: SVOM/VT afterglow detection
  94. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  95. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  96. GRB 241112B: Mephisto optical upper limits
  97. GRB 241112B: GOTO optical upper limits
  98. GRB 241112B: Swift ToO observations
  99. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  100. GRB 241107A: INTEGRAL IBIS localization

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