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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"

36273 results found.

  1. GRB 241113A: J-band observations with WINTER
  2. GRB 241030A: LCO optical observation
  3. GRB 241113B: Swift-XRT observations
  4. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  5. GRB 241113A: KAIT optical observations
  6. EP241113b/GRB 241113B: EP detection of GRB 241113B
  7. GRB 241113B: SVOM/GRM observation
  8. GRB 241113A: Swift-XRT refined Analysis
  9. GRB 241113A: Swift/UVOT Detection
  10. GRB 241113A: REM detection of the optical/NIR afterglow
  11. Konus-Wind detection of GRB 241107A (short/hard)
  12. Fermi Gamma-ray Burst Monitor trigger 753166198/241113201 is not a GRB
  13. GRB 241113B: Swift ToO observations
  14. GRB 241113A: LCO optical observations
  15. GRB 241112B: GMG Optical Upper Limit
  16. GRB 241113A: Enhanced Swift-XRT position
  17. GRB241113A: LCOGT (40-cm) optical counterpart detection
  18. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  19. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  20. GRB 241113A: Swift detection of a burst with an optical counterpart
  21. GRB 241105A: ATCA Radio Upper Limits
  22. GRB 241112B: AbAO optical upper limit
  23. GRB 241107A: GROWTH-India telescope optical upper limit
  24. Fermi GRB 241112A: Global MASTER-Net observations report
  25. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  26. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  27. GRB 241112B: Swift-XRT afterglow detection
  28. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  29. GRB 241112B: SVOM/GRM observation
  30. GRB 241112B: SVOM/VT afterglow detection
  31. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  32. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  33. GRB 241112B: Mephisto optical upper limits
  34. GRB 241112B: GOTO optical upper limits
  35. GRB 241112B: Swift ToO observations
  36. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  37. GRB 241107A: INTEGRAL IBIS localization
  38. GRB 241112A: Fermi GBM Final Real-time Localization
  39. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  40. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  41. IPN triangulation of GRB 241107A (short/hard)
  42. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  43. GRB 241025C: VZLUSAT-2 detection
  44. GRB 241025A: VZLUSAT-2 detection
  45. GRB 241018A: cubesat Avion detection
  46. GRB 241111A: Fermi GBM Final Real-time Localization
  47. GRB 241030B: TESS detection of optical counterpart
  48. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  49. EP241107a: AbAO optical upper limit
  50. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  51. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  52. GRB 241108A: Swift-XRT observations
  53. EP241107A: MASTER optical observations of xray transient
  54. EP241107a: KAIT optical observations
  55. GRB 241108A: Swift ToO observations
  56. GRB 241030A: TESS observations
  57. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  58. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  59. GRB 241025A: radio detection with the VLA
  60. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  61. GRB 241107A: SVOM/GRM detection of a short burst
  62. GRB 241105A: EP-FXT follow-up observations
  63. GRB 241105A: SVOM/GRM observation
  64. GRB 241105a: PRIME near-infrared upper limits
  65. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  66. GRB 241025A: LBT optical observations
  67. GRB241105A: Gemini-South Optical Afterglow Detection
  68. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  69. GRB 241105A: Swift/UVOT Detection
  70. EP241101a: CrAO ZTSH optical observations
  71. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  72. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  73. GRB 241105A: BOOTES-7 optical detection
  74. GRB 241030A: Mondy optical observations
  75. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  76. Konus-Wind detection of GRB 241105A (short with extended emission)
  77. Konus-Wind detection of GRB 241021A
  78. GRB 241105A: SVOM/VT optical afterglow observations
  79. GRB 241105A: Swift-XRT afterglow detection
  80. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  81. GRB 241104A: Swift-XRT observations
  82. GRB 240511A: LCO upper limits
  83. GRB 241104A: Fermi GBM Observation
  84. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  85. GRB 241105A: Swift ToO observations
  86. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  87. GRB 241104A: Swift ToO observations
  88. GRB 241104A: NOT optical non-detection
  89. GRB 241105A: GOTO tentative optical counterpart candidate
  90. Fermi GRB 241105A: Global MASTER-Net observations report
  91. GRB 241104A: SVOM/VT optical candidate
  92. GRB 241105A: Fermi GBM Final Real-time Localization
  93. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  94. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  95. GRB 241104A: SVOM/GRM observation
  96. EP241104a: EP detection of GRB 241104A X-ray emission
  97. GRB 241010A: host galaxy redshift z = 0.977
  98. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  99. GRB 240821A: further radio observations with the VLA
  100. Fermi GRB 241104A: Global MASTER-Net observations report

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