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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"

36179 results found.

  1. GRB 241128A: Swift-XRT afterglow detection
  2. GRB 241128A: Swift detection of a burst
  3. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  4. GRB 241127A: Swift/UVOT Detection
  5. GRB 241127A: Swift-XRT refined Analysis
  6. GRB 241127A: SVOM/GRM observation
  7. GRB 241127A: Enhanced Swift-XRT position
  8. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  9. GRB 241127A: Swift detection of a burst with an optical counterpart
  10. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  11. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  12. GRB 241126A: SVOM/GRM observation
  13. IPN triangulation of GRB 241114B
  14. GRB 241113B: EP-FXT afterglow detection
  15. Konus-Wind detection of GRB 241115D / EP 241115a
  16. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  17. GRB 241026A: radio detection with the VLA
  18. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  19. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  20. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  21. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  22. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  23. GRB 241120A: GRBAlpha detection
  24. GRB 241113B: SVOM/VT optical afterglow observations
  25. Konus-Wind detection of GRB 241117A
  26. GRB 241105A: ATCA radio detection
  27. IPN triangulation of GRB 241117A
  28. GRB 241026A: VIRT Optical Upper Limit
  29. GRB 241025A: VIRT Optical Upper Limit
  30. Konus-Wind detection of GRB 241120A
  31. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  32. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  33. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  34. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  35. GRB 241120A: Mondy and AbAO optical observations
  36. GRB 241113A: Possible ATCA Radio detection
  37. GRB 241120A: Fermi GBM Observation
  38. GRB 241114B: Insight-HXMT/HE detection
  39. GRB241120A: a long GRB detected by INTEGRAL
  40. GRB 241120A: Fermi GBM Final Real-time Localization
  41. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  42. GRB 241112B: Mephisto further optical observations
  43. GRB 241119A: Fermi GBM Final Real-time Localization
  44. GRB 241030A: J-band observations
  45. GRB 241115a: PRIME near-infrared upper limits
  46. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  47. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  48. GRB 241115B: Fermi GBM Observation
  49. Fermi GRB 241118A: Global MASTER-Net observations report
  50. GRB 241118A: Fermi GBM Final Real-time Localization
  51. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  52. GRB 241117A: Fermi GBM Detection
  53. Fermi GRB 241117B: Global MASTER-Net observations report
  54. GRB 241117B: Fermi GBM Final Real-time Localization
  55. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  56. Fermi GRB 241117A: Global MASTER-Net observations report
  57. GRB 241117A: Fermi GBM Final Real-time Localization
  58. GRB 241115C: Fermi GBM Observation
  59. GRB 241115A: Swift-XRT afterglow detection
  60. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  61. GRB 241115A: Mephisto upper limits
  62. GRB 241113B: Mephisto upper limits
  63. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  64. GRB 241115D / EP 241115a: SVOM/GRM observation
  65. GRB 241115A: Fermi GBM Observation
  66. GRB 241115A: LCOGT Optical Upper Limits
  67. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  68. Fermi GRB 241115B: Global MASTER-Net observations report
  69. GRB 241115B: Fermi GBM Final Real-time Localization
  70. EP241113a: No Detection in Fermi-GBM Observations
  71. Swift GRB 241115A: Global MASTER-Net observations report
  72. Fermi GRB 241115A: Global MASTER-Net observations report
  73. GRB 241115A: Swift detection of a burst
  74. GRB 241115A: Fermi GBM Final Real-time Localization
  75. GRB 241113B: KAIT Optical Afterglow Candidate
  76. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  77. GRB 241113A: Swift-BAT refined analysis
  78. GRB 241113A: PRIME near-infrared upper limits
  79. Fermi GRB 241114A: Global MASTER-Net observations report
  80. GRB 241114A: Fermi GBM Final Real-time Localization
  81. GRB 241113B: J-band upper limit from WINTER
  82. GRB 241113A: J-band observations with WINTER
  83. GRB 241030A: LCO optical observation
  84. GRB 241113B: Swift-XRT observations
  85. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  86. GRB 241113A: KAIT optical observations
  87. EP241113b/GRB 241113B: EP detection of GRB 241113B
  88. GRB 241113B: SVOM/GRM observation
  89. GRB 241113A: Swift-XRT refined Analysis
  90. GRB 241113A: Swift/UVOT Detection
  91. GRB 241113A: REM detection of the optical/NIR afterglow
  92. Konus-Wind detection of GRB 241107A (short/hard)
  93. Fermi Gamma-ray Burst Monitor trigger 753166198/241113201 is not a GRB
  94. GRB 241113B: Swift ToO observations
  95. GRB 241113A: LCO optical observations
  96. GRB 241112B: GMG Optical Upper Limit
  97. GRB 241113A: Enhanced Swift-XRT position
  98. GRB241113A: LCOGT (40-cm) optical counterpart detection
  99. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  100. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection

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