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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"

37579 results found.

  1. GRB 241213A: REM optical/NIR upper limits
  2. GRB 241213A: Enhanced Swift-XRT position
  3. GRB241212A: OHP/T193 optical observations
  4. GRB 241213A: SAO RAS optical upper limit
  5. Swift GRB 241213A: Global MASTER-Net observations report
  6. GRB 241213A: Swift detection of a burst
  7. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  8. GRB 241212A : SVOM/VT bright optical afterglow
  9. GRB 241212A: AstroSat CZTI detection
  10. GRB 241209B: GRANDMA/TRT upper limit
  11. GRB 241207A: TSHAO Zeiss-1000 optical observations
  12. GRB 241212A: SVOM detection of a bright long burst
  13. GRB 241212A: Fermi GBM Final Real-time Localization
  14. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  15. GRB 241209A: Chandra X-ray Detection
  16. Konus-Wind detection of GRB 241209B
  17. GRB 241207A: EIRSAT-1 GMOD Detection
  18. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  19. GRB 241209B: GRBAlpha detection
  20. GRB 241206C: GRBAlpha detection
  21. GRB 241211A: Fermi GBM Final Real-time Localization
  22. GRB 241129A: Fermi GBM Observation
  23. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  24. GRB 241209D: REM optical/NIR upper limits
  25. Konus-Wind detection of GRB 241209D
  26. GRB 241209B: Swift-XRT afterglow detection
  27. GRB 241209C: Fermi GBM Observation
  28. GRB 241209A: Swift-XRT refined Analysis
  29. Fermi Gamma-ray Burst Monitor trigger 755485387 / 241210044 is not a GRB
  30. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  31. GRB 241209D: AstroSat CZTI detection
  32. GRB 241209A: EP-FXT follow-up observations
  33. GRB 241209B: SVOM/VT afterglow detection
  34. Fermi trigger No 755485387: Global MASTER-Net observations report
  35. GRB 241207B: Fermi GBM Observation
  36. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  37. GRB 241209D: Swift-XRT refined Analysis
  38. GRB 241209D: Fermi GBM Observation
  39. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  40. GRB 241209D: COLIBRÍ detection of the afterglow
  41. GRB 241209A: COLIBRÍ Optical Upper Limit
  42. Fermi GRB 241209D: Global MASTER-Net observations report
  43. GRB 241209A: Fermi GBM Observation
  44. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  45. GRB 241209A: GRANDMA/TAROT upper limit
  46. GRB 241209B: BOOTES-5 optical upper limit
  47. Swift GRB 241209D: Global MASTER-Net observations report
  48. Fermi GRB 241209C: Global MASTER-Net observations report
  49. Fermi GRB 241209E: Global MASTER-Net observations report
  50. GRB 241209E: Fermi GBM Final Real-time Localization
  51. GRB 241209B: Swift ToO observations
  52. GRB 241209A: REM optical/NIR observations
  53. GRB 241209D: Enhanced Swift-XRT position
  54. GRB 241209C: AstroSat CZTI detection
  55. GRB 241209D: Swift detection of a burst
  56. GRB 241209D: Fermi GBM Final Real-time Localization
  57. GRB 241209A: VLT/X-shooter spectroscopy
  58. GRB 241209A: Enhanced Swift-XRT position
  59. GRB 241114B: cubesat Avion detection
  60. GRB 241209A: VLT optical observations
  61. Fermi GRB 241209A: Global MASTER-Net observations report
  62. GRB 241209C: Fermi GBM Final Real-time Localization
  63. GRB 241209A: GOTO optical upper limits
  64. GRB 241209A: Prompt enhanced Swift-XRT position
  65. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  66. GRB 241209A: Swift detection of a short burst
  67. GRB 241209A: Fermi GBM Final Real-time Localization
  68. Fermi GRB 241207B: Global MASTER-Net observations report
  69. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  70. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  71. GRB 241201A: AstroSat CZTI detection
  72. GRB 241206A: DDOTI Upper Limit on the Afterglow
  73. GRB 241207C: MASTER optical observations
  74. Fermi trigger No 755225799: Global MASTER-Net observations report
  75. GRB 241207C: Tiled Swift observations
  76. GRB 241207C: MAXI/GSC detection
  77. GRB 241207B: Fermi GBM Final Real-time Localization
  78. Fermi trigger No 755277791: Global MASTER-Net observations report
  79. Fermi GRB 241207A: Global MASTER-Net observations report
  80. GRB 241206A: Fermi GBM observation
  81. GRB 241206C: SVOM/GRM observation of a likely short burst
  82. GRB 241207A: Fermi GBM Final Real-time Localization
  83. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  84. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  85. GRB 241206B: GWAC-F50A optical upper limit
  86. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  87. Fermi GRB 241206A: Global MASTER-Net observations report
  88. GRB 241206A: Fermi GBM Final Real-time Localization
  89. GRB 241204A: COLIBRÍ Optical Upper Limit
  90. EP241202b: KAIT optical upper limit
  91. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  92. GRB 241204A: DDOTI Upper Limits on the Afterglow
  93. GRB 241204A: Fermi GBM Observation
  94. Fermi GRB 241204A: Global MASTER-Net observations report
  95. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  96. GRB 241128A : RAPAS follow-up observations
  97. GRB 241201A: GRBAlpha detection
  98. GRB 241204A: Fermi-LAT detection
  99. EP241202b: Upper limits from Fermi-GBM Observations
  100. Fermi-GBM Sub-Threshold Detection of GRB 241128A

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