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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').
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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"

28297 results found.

  1. GRB 241218A: Swift-XRT refined Analysis
  2. EP241217a: NOT optical observations
  3. EP241217a: GROWTH-India Telescope optical observations
  4. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  5. EP241119a: 7DT Optical upper limits
  6. EP241217a: Xinglong optical follow-up observations
  7. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  8. GRB 241218A: LCOGT Optical Upper Limit
  9. GRB 241218A: Enhanced Swift-XRT position
  10. GRB 241217A: GMG Optical Upper Limit
  11. GRB 241218A: Swift detection of a burst
  12. GRB 241217A : SVOM/VT optical afterglow detection
  13. GRB 241217A: Swift-XRT afterglow detection
  14. GRB 241217A: LCO optical upper limit
  15. GRB 241217A: GRANDMA/TAROT optical upperlimits
  16. EP241217a: Swift-XRT Detection
  17. EP241217A: Non-detection from Fermi-GBM Observations
  18. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  19. EP241217a: Kinder optical follow-up observations
  20. EP241217A: LCO optical observations
  21. EP241217a: Gemini-North detection of the likely optical counterpart
  22. EP241217a: EP detection of an X-ray transient
  23. EP241107a: VLA Radio Observation
  24. GRB 241213A: Swift-BAT refined analysis
  25. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  26. GRB 241215A: Mondy AZT-33IK optical observations
  27. GRB 241212A: Swift-XRT observations
  28. GRB 241215A: Nanshan/HMT optical upper limit
  29. GRB 241215A: Montarrenti Observatory optical upper limit
  30. GRB 241215A: GROWTH-India telescope optical upper limit
  31. GRB 241215A: A long GRB detected by INTEGRAL
  32. Integral GRB241215.58: Global MASTER-Net observations report
  33. GRB 241213B: Swift-XRT observations
  34. GRB 241213A: Swift/UVOT Upper Limits
  35. GRB 241213A: Swift-XRT refined Analysis
  36. GRB 241212A: Fermi GBM detection
  37. EP241208a: NOT optical upper limits
  38. GRB 241213A: LCOGT Optical Upper Limits
  39. GRB 241213B: MAXI/GSC detection
  40. EP241213a: EP detection of An X-ray Transient
  41. GRB 241213A: REM optical/NIR upper limits
  42. GRB 241213A: Enhanced Swift-XRT position
  43. GRB241212A: OHP/T193 optical observations
  44. GRB 241213A: SAO RAS optical upper limit
  45. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  46. GRB 241213A: Swift detection of a burst
  47. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  48. GRB 241212A: AstroSat CZTI detection
  49. GRB 241209B: GRANDMA/TRT upper limit
  50. GRB 241207A: TSHAO Zeiss-1000 optical observations
  51. GRB 241212A: SVOM detection of a bright long burst
  52. GRB 241207A: EIRSAT-1 GMOD Detection
  53. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  54. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  55. GRB 241129A: Fermi GBM Observation
  56. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  57. GRB 241209D: REM optical/NIR upper limits
  58. GRB 241209B: Swift-XRT afterglow detection
  59. GRB 241209C: Fermi GBM Observation
  60. GRB 241209A: Swift-XRT refined Analysis
  61. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  62. EP241208a: Optical upper limit with Kinder observations
  63. GRB 241209B: SVOM/VT afterglow detection
  64. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  66. GRB 241207B: Fermi GBM Observation
  67. GRB 241209D: Swift-XRT refined Analysis
  68. GRB 241209D: Fermi GBM Observation
  69. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  70. GRB 241209D: COLIBRÍ detection of the afterglow
  71. GRB 241209A: COLIBRÍ Optical Upper Limit
  72. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  73. GRB 241209A: GRANDMA/TAROT upper limit
  74. GRB 241209A: REM optical/NIR observations
  75. GRB 241209D: Enhanced Swift-XRT position
  76. GRB 241209D: Swift detection of a burst
  77. GRB 241209A: Enhanced Swift-XRT position
  78. GRB 241114B: cubesat Avion detection
  79. GRB 241209A: VLT optical observations
  80. GRB 241209A: GOTO optical upper limits
  81. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  82. EP241208a: EP detection of a fast X-ray transient
  83. GRB 241209A: Swift detection of a short burst
  84. Fermi GRB 241207B: Global MASTER-Net observations report
  85. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  86. GRB 241206A: DDOTI Upper Limit on the Afterglow
  87. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  88. GRB 241207C: MAXI/GSC detection
  89. EP241206a: EP detection of a fast X-ray transient
  90. GRB 241206A: Fermi GBM observation
  91. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  92. EP241201a: 1.6m Mephisto Optical Upper Limits
  93. GRB 241204A: COLIBRÍ Optical Upper Limit
  94. EP241202b: KAIT optical upper limit
  95. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  96. GRB 241204A: DDOTI Upper Limits on the Afterglow
  97. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  98. GRB 241128A : RAPAS follow-up observations
  99. EP241202b: Upper limits from Fermi-GBM Observations
  100. IceCube-241127A: No transient candidates from the Zwicky Transient Facility

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