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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"

27227 results found.

  1. GRB 241217A / EP241217b: Non-detection in ATCA Radio Follow-up Observations
  2. The EP-WXT trigger 01709129287 is likely a flaring star
  3. Fermi trigger No 756447119: Global MASTER-Net observations report
  4. Fermi Gamma-ray Burst Monitor trigger 756447119/241221175 is not a GRB
  5. Fermi GRB 241221A: Global MASTER-Net observations report
  6. GRB 241221A: Fermi GBM Final Real-time Localization
  7. EP241217a: Liverpool Telescope optical upper limit
  8. EP241021a: VLA radio detection
  9. GRB 241218A: Mondy AZT-33IK optical upper limit
  10. EP241217a : Leavitt Observatory optical upper limit
  11. GRB 241217A/EP241217b: tentative VLT spectroscopic redshift z=1.879
  12. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  13. GRB 241218A: Swift/UVOT Upper Limits
  14. EP241217a: optical upper limit with the Liverpool Telescope
  15. GRB 241209B: EP-FXT afterglow detection
  16. GRB 241218A: NOT optical upper limits
  17. GRB 241218A: Swift-BAT refined analysis
  18. GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
  19. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  20. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  21. GRB 241217A: refined SVOM/MXT data analysis. Long lasting X-ray emission.
  22. GRB 241217A / EP241217b: NOT optical upper limits
  23. GRB 241218A: REM optical upper limit
  24. GRB 241217A/EP241217b: REM optical/NIR upper limits
  25. EP241217a: REM optical/NIR upper limits
  26. GRB 241218a: Liverpool Telescope optical follow-up
  27. GRB 241217a: Liverpool Telescope optical follow-up
  28. EP241217a: Liverpool Telescope optical follow-up
  29. GRB 241218A: Swift-XRT refined Analysis
  30. EP241217a: NOT optical observations
  31. EP241217a: GROWTH-India Telescope optical observations
  32. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  33. EP241217b: Global MASTER-Net observations report
  34. EP241217a: Xinglong optical follow-up observations
  35. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  36. GRB 241218A: LCOGT Optical Upper Limit
  37. EP241217a: Global MASTER-Net observations report
  38. GRB 241217A: GMG Optical Upper Limit
  39. GRB 241218A: Swift detection of a burst
  40. GRB 241217A : SVOM/VT optical afterglow detection
  41. EP241217a: Swift-XRT Detection
  42. EP241217A: Non-detection from Fermi-GBM Observations
  43. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  44. EP241217a: Kinder optical follow-up observations
  45. GRB 241214A: GRBAlpha detection
  46. EP241217A: LCO optical observations
  47. EP241217a: EP detection of an X-ray transient
  48. The EP-WXT trigger 01709129023 is likely a flaring star
  49. GRB 241213A: Swift-BAT refined analysis
  50. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  51. GRB 241215A: Mondy AZT-33IK optical observations
  52. GRB 241214A: SVOM/GRM observation
  53. The EP-WXT trigger 01709128948 is likely a flaring star
  54. GRB 241215A: Nanshan/HMT optical upper limit
  55. GRB 241215A: GROWTH-India telescope optical upper limit
  56. Integral GRB241215.58: Global MASTER-Net observations report
  57. The EP-WXT trigger 01709128921 is likely a flaring star
  58. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  59. GRB 241209B: SVOM/VT optical continuous fading
  60. EP trigger ID 01709128824 is not a real source
  61. GRB 241213A: SVOM/VT optical candidate
  62. GRB 241213A: Swift/UVOT Upper Limits
  63. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  64. GRB 241213A: Swift-XRT refined Analysis
  65. GRB 241212A: Fermi GBM detection
  66. EP241208a: NOT optical upper limits
  67. GRB 241213A: LCOGT Optical Upper Limits
  68. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  69. EP241213a: EP detection of An X-ray Transient
  70. GRB 241213A: REM optical/NIR upper limits
  71. GRB 241213A: SAO RAS optical upper limit
  72. Swift GRB 241213A: Global MASTER-Net observations report
  73. GRB 241213A: Swift detection of a burst
  74. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  75. GRB 241212A : SVOM/VT bright optical afterglow
  76. GRB 241207A: TSHAO Zeiss-1000 optical observations
  77. GRB 241212A: SVOM detection of a bright long burst
  78. GRB 241212A: Fermi GBM Final Real-time Localization
  79. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  80. Konus-Wind detection of GRB 241209B
  81. GRB 241211A: Fermi GBM Final Real-time Localization
  82. GRB 241129A: Fermi GBM Observation
  83. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  84. GRB 241209D: REM optical/NIR upper limits
  85. GRB 241209C: Fermi GBM Observation
  86. GRB 241209A: Swift-XRT refined Analysis
  87. Fermi Gamma-ray Burst Monitor trigger 755485387 / 241210044 is not a GRB
  88. EP241208a: Optical upper limit with Kinder observations
  89. GRB 241209A: EP-FXT follow-up observations
  90. GRB 241209B: SVOM/VT afterglow detection
  91. EP241208a: Global MASTER-Net observations report
  92. EP241208a: EP-FXT follow-up observations
  93. Fermi trigger No 755485387: Global MASTER-Net observations report
  94. GRB 241207B: Fermi GBM Observation
  95. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  96. GRB 241209D: Swift-XRT refined Analysis
  97. GRB 241209D: Fermi GBM Observation
  98. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  99. GRB 241209D: COLIBRÍ detection of the afterglow
  100. GRB 241209A: COLIBRÍ Optical Upper Limit

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