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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"

36384 results found.

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

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