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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.

Advanced Search Examples (click to copy):

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

36351 results found.

  1. GRB 241120A: Fermi GBM Observation
  2. GRB 241114B: Insight-HXMT/HE detection
  3. GRB241120A: a long GRB detected by INTEGRAL
  4. GRB 241120A: Fermi GBM Final Real-time Localization
  5. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  6. GRB 241112B: Mephisto further optical observations
  7. GRB 241119A: Fermi GBM Final Real-time Localization
  8. GRB 241030A: J-band observations
  9. GRB 241115a: PRIME near-infrared upper limits
  10. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  11. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  12. GRB 241115B: Fermi GBM Observation
  13. Fermi GRB 241118A: Global MASTER-Net observations report
  14. GRB 241118A: Fermi GBM Final Real-time Localization
  15. Updates to IceCube realtime alert system for muon tracks
  16. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  17. GRB 241117A: Fermi GBM Detection
  18. Fermi GRB 241117B: Global MASTER-Net observations report
  19. GRB 241117B: Fermi GBM Final Real-time Localization
  20. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  21. Fermi GRB 241117A: Global MASTER-Net observations report
  22. GRB 241117A: Fermi GBM Final Real-time Localization
  23. GRB 241115C: Fermi GBM Observation
  24. GRB 241115A: Swift-XRT afterglow detection
  25. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  26. GRB 241115A: Mephisto upper limits
  27. GRB 241113B: Mephisto upper limits
  28. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  29. GRB 241115D / EP 241115a: SVOM/GRM observation
  30. GRB 241115A: Fermi GBM Observation
  31. GRB 241115A: LCOGT Optical Upper Limits
  32. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  33. Fermi GRB 241115B: Global MASTER-Net observations report
  34. GRB 241115B: Fermi GBM Final Real-time Localization
  35. EP241113a: No Detection in Fermi-GBM Observations
  36. Swift GRB 241115A: Global MASTER-Net observations report
  37. Fermi GRB 241115A: Global MASTER-Net observations report
  38. GRB 241115A: Swift detection of a burst
  39. GRB 241115A: Fermi GBM Final Real-time Localization
  40. GRB 241113B: KAIT Optical Afterglow Candidate
  41. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  42. GRB 241113A: Swift-BAT refined analysis
  43. GRB 241113A: PRIME near-infrared upper limits
  44. Fermi GRB 241114A: Global MASTER-Net observations report
  45. GRB 241114A: Fermi GBM Final Real-time Localization
  46. GRB 241113B: J-band upper limit from WINTER
  47. GRB 241113A: J-band observations with WINTER
  48. GRB 241030A: LCO optical observation
  49. GRB 241113B: Swift-XRT observations
  50. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  51. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  52. GRB 241113A: KAIT optical observations
  53. EP241113b/GRB 241113B: EP detection of GRB 241113B
  54. GRB 241113B: SVOM/GRM observation
  55. GRB 241113A: Swift-XRT refined Analysis
  56. GRB 241113A: Swift/UVOT Detection
  57. GRB 241113A: REM detection of the optical/NIR afterglow
  58. Konus-Wind detection of GRB 241107A (short/hard)
  59. Fermi Gamma-ray Burst Monitor trigger 753166198/241113201 is not a GRB
  60. GRB 241113B: Swift ToO observations
  61. GRB 241113A: LCO optical observations
  62. GRB 241112B: GMG Optical Upper Limit
  63. GRB 241113A: Enhanced Swift-XRT position
  64. GRB241113A: LCOGT (40-cm) optical counterpart detection
  65. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  66. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  67. GRB 241113A: Swift detection of a burst with an optical counterpart
  68. GRB 241105A: ATCA Radio Upper Limits
  69. GRB 241112B: AbAO optical upper limit
  70. GRB 241107A: GROWTH-India telescope optical upper limit
  71. Fermi GRB 241112A: Global MASTER-Net observations report
  72. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  73. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  74. GRB 241112B: Swift-XRT afterglow detection
  75. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  76. GRB 241112B: SVOM/GRM observation
  77. GRB 241112B: SVOM/VT afterglow detection
  78. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  79. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  80. GRB 241112B: Mephisto optical upper limits
  81. GRB 241112B: GOTO optical upper limits
  82. GRB 241112B: Swift ToO observations
  83. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  84. GRB 241107A: INTEGRAL IBIS localization
  85. GRB 241112A: Fermi GBM Final Real-time Localization
  86. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  87. IPN triangulation of GRB 241107A (short/hard)
  88. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  89. GRB 241025C: VZLUSAT-2 detection
  90. GRB 241025A: VZLUSAT-2 detection
  91. GRB 241018A: cubesat Avion detection
  92. GRB 241111A: Fermi GBM Final Real-time Localization
  93. GRB 241030B: TESS detection of optical counterpart
  94. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  95. EP241107a: AbAO optical upper limit
  96. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  97. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  98. EP241109a: confirmation of a stellar flare by BOOTES-7
  99. GRB 241108A: Swift-XRT observations
  100. EP241107A: MASTER optical observations of xray transient

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