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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

28283 results found.

  1. GRB 241217A : SVOM/VT optical afterglow detection
  2. GRB 241217A: Swift-XRT afterglow detection
  3. GRB 241217A: LCO optical upper limit
  4. GRB 241217A: GRANDMA/TAROT optical upperlimits
  5. EP241217a: Swift-XRT Detection
  6. EP241217A: Non-detection from Fermi-GBM Observations
  7. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  8. EP241217a: Kinder optical follow-up observations
  9. EP241217A: LCO optical observations
  10. EP241217a: Gemini-North detection of the likely optical counterpart
  11. EP241217a: EP detection of an X-ray transient
  12. EP241107a: VLA Radio Observation
  13. GRB 241213A: Swift-BAT refined analysis
  14. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  15. GRB 241215A: Mondy AZT-33IK optical observations
  16. GRB 241212A: Swift-XRT observations
  17. GRB 241215A: Nanshan/HMT optical upper limit
  18. GRB 241215A: Montarrenti Observatory optical upper limit
  19. GRB 241215A: GROWTH-India telescope optical upper limit
  20. GRB 241215A: A long GRB detected by INTEGRAL
  21. Integral GRB241215.58: Global MASTER-Net observations report
  22. GRB 241213B: Swift-XRT observations
  23. GRB 241213A: Swift/UVOT Upper Limits
  24. GRB 241213A: Swift-XRT refined Analysis
  25. GRB 241212A: Fermi GBM detection
  26. EP241208a: NOT optical upper limits
  27. GRB 241213A: LCOGT Optical Upper Limits
  28. GRB 241213B: MAXI/GSC detection
  29. EP241213a: EP detection of An X-ray Transient
  30. GRB 241213A: REM optical/NIR upper limits
  31. GRB 241213A: Enhanced Swift-XRT position
  32. GRB241212A: OHP/T193 optical observations
  33. GRB 241213A: SAO RAS optical upper limit
  34. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  35. GRB 241213A: Swift detection of a burst
  36. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  37. GRB 241212A: AstroSat CZTI detection
  38. GRB 241209B: GRANDMA/TRT upper limit
  39. GRB 241207A: TSHAO Zeiss-1000 optical observations
  40. GRB 241212A: SVOM detection of a bright long burst
  41. GRB 241207A: EIRSAT-1 GMOD Detection
  42. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  43. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  44. GRB 241129A: Fermi GBM Observation
  45. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  46. GRB 241209D: REM optical/NIR upper limits
  47. GRB 241209B: Swift-XRT afterglow detection
  48. GRB 241209C: Fermi GBM Observation
  49. GRB 241209A: Swift-XRT refined Analysis
  50. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  51. EP241208a: Optical upper limit with Kinder observations
  52. GRB 241209B: SVOM/VT afterglow detection
  53. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  54. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  55. GRB 241207B: Fermi GBM Observation
  56. GRB 241209D: Swift-XRT refined Analysis
  57. GRB 241209D: Fermi GBM Observation
  58. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  59. GRB 241209D: COLIBRÍ detection of the afterglow
  60. GRB 241209A: COLIBRÍ Optical Upper Limit
  61. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  62. GRB 241209A: GRANDMA/TAROT upper limit
  63. GRB 241209A: REM optical/NIR observations
  64. GRB 241209D: Enhanced Swift-XRT position
  65. GRB 241209D: Swift detection of a burst
  66. GRB 241209A: Enhanced Swift-XRT position
  67. GRB 241114B: cubesat Avion detection
  68. GRB 241209A: VLT optical observations
  69. GRB 241209A: GOTO optical upper limits
  70. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  71. EP241208a: EP detection of a fast X-ray transient
  72. GRB 241209A: Swift detection of a short burst
  73. Fermi GRB 241207B: Global MASTER-Net observations report
  74. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  75. GRB 241206A: DDOTI Upper Limit on the Afterglow
  76. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  77. GRB 241207C: MAXI/GSC detection
  78. EP241206a: EP detection of a fast X-ray transient
  79. GRB 241206A: Fermi GBM observation
  80. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  81. EP241201a: 1.6m Mephisto Optical Upper Limits
  82. GRB 241204A: COLIBRÍ Optical Upper Limit
  83. EP241202b: KAIT optical upper limit
  84. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  85. GRB 241204A: DDOTI Upper Limits on the Afterglow
  86. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  87. GRB 241128A : RAPAS follow-up observations
  88. EP241202b: Upper limits from Fermi-GBM Observations
  89. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  90. EP241202b: Kinder optical counterpart candidate
  91. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  92. GRB 241113B : RAPAS follow-up observation
  93. Konus-Wind detection of GRB 241130A
  94. EP241201a: BOOTES-5 optical upper limit
  95. EP241202b: EP detection of a fast X-ray transient
  96. EP241201a: NOT optical observations
  97. IPN triangulation of GRB 241130A
  98. GRB 241130A: EIRSAT-1 GMOD Detection
  99. GRB 241128A: Swift/UVOT Upper Limits
  100. GRB 241130A: Fermi GBM Detection

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