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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"

32551 results found.

  1. GRB 231205B: Nanshan/HMT optical upper limit
  2. GRB 231205B: GECAM-B detection of a long burst
  3. GRB 231205B: LCOGT Optical Upper Limits
  4. GRB 231205A: DDOTI Upper Limits on the Afterglow
  5. GRB 231204A: Glowbug gamma-ray detection
  6. GRB 231204A: CALET Gamma-Ray Burst Monitor detection
  7. GRB 231205B: AKO Optical Upper Limit
  8. GRB 231205A: joint location of multiple instruments by ETJASMIN
  9. GRB 231204A: AstroSat CZTI detection
  10. GRB 231205A: GECAM-B detection of a short burst
  11. IceCube-231202A: Upper limits from a search for additional neutrino events in IceCube
  12. GRB 231203A: Fermi GBM Observation
  13. Konus-Wind detection of GRB 231129C
  14. GRB 231129C: PROMPT optical upper limits for the MAXI/GSC X-ray counterpart and the MASTER afterglow candidate
  15. GRB 231129A: VZLUSAT-2 detection
  16. GRB 231128A: VZLUSAT-2 detection
  17. Optical transient in the field of Messier 31, likely a new blazar: back to bright state
  18. GRB 231129C: AGILE detection
  19. GRB 231129A : MITSuME Akeno optical upper limits
  20. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  21. GRB 231129A: Swift-BAT refined analysis
  22. GRB 231129C: MASTER OT detection
  23. GRB 231129C: Fermi-LAT detection
  24. GRB 231129A: JinShan optical upper limit
  25. GRB 231129C: GRBAlpha detection
  26. GRB 231129C: Glowbug gamma-ray detection
  27. GRB 231129A: Swift/UVOT Upper Limits
  28. GRB 231129A: optical upper limit in Mondy observatory
  29. GRB 231129C: GECAM-B detection of a bright burst
  30. GRB 231129C: AstroSat CZTI detection
  31. GRB 231129C: iTelescope OT retraction
  32. GRB 231129C: CALET Gamma-Ray Burst Monitor detection
  33. GRB 231129C: Fermi GBM Observation of a very bright GRB
  34. GRB 231129C: iTelescope likely optical afterglow AT 2023yph discovery
  35. GRB 231129C: Tiled Swift observations
  36. GRB 231127A: GRBAlpha detection
  37. LIGO/Virgo/KAGRA S231129ac: Updated Sky localization
  38. GRB 231129B: Tiled Swift observations
  39. Fermi-LAT gamma-ray observations of IceCube-231125A
  40. LIGO/Virgo/KAGRA S231129ac: Identification of a GW compact binary merger candidate
  41. GRB 231129A: GECAM-C detection of a long burst
  42. GRB 231129A: INTEGRAL detection of a long GRB
  43. LIGO/Virgo/KAGRA S231127cg: Updated Sky localization
  44. GRB 231123C: Fermi GBM Observation
  45. GRB 231123B: Fermi GBM Observation
  46. IceCube-231125A: Upper limits from a search for additional neutrino events in IceCube
  47. LIGO/Virgo/KAGRA S231127cg: Identification of a GW compact binary merger candidate
  48. GRB 231117A: MeerKAT 1.3GHz detection
  49. GRB 231127A: CALET Gamma-Ray Burst Monitor detection
  50. GRB 231125A: GRBAlpha detection
  51. GRB 231125A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 231125A (short): Glowbug gamma-ray detection
  53. Update of IceCube-231125A - Corrected errors
  54. GRB 231124A: GRBAlpha detection
  55. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  56. GRB 231123C: Insight-HXMT/HE detection
  57. GRB 231123C (short): Glowbug gamma-ray detection
  58. GRB 231124A: Glowbug gamma-ray detection
  59. GRB230728A: VIRT optical upper limit
  60. GRB230506C: VIRT optical upper limit
  61. GRB230506B: VIRT optical upper limit
  62. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  63. LIGO/Virgo/KAGRA S231118an: Updated Sky localization and EM Bright Classification
  64. GRB 231124A: CALET Gamma-Ray Burst Monitor detection
  65. GRB 231115A: XMM-Newton observation
  66. GRB 231123A: AstroSat CZTI detection
  67. GRB 231117A: Mondy optical observations
  68. LIGO/Virgo/KAGRA S231123cg: Identification of a GW compact binary merger candidate
  69. GRB 231118A: REM optical afterglow detection
  70. GRB 231122B: AstroSat CZTI detection
  71. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  72. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  73. GRB 231117A: Chandra afterglow detection
  74. GRB 231122B: Glowbug gamma-ray detection
  75. GRB 231117A: Continued GTC Observations
  76. GRB 231122A: GECAM detection
  77. GRB 231118A: ATCA detection of radio counterpart
  78. GRB 231117A: Swift/UVOT late time observations
  79. GRB 231117A: GTC Near-Infrared Observations
  80. GRB 231117A: Swift-BAT refined analysis
  81. GRB 231118A: GRBAlpha detection
  82. LIGO/Virgo/KAGRA S231119u: Updated Sky localization and Source Classification
  83. LIGO/Virgo/KAGRA S231118ab: Updated Sky localization and Source Classification
  84. LIGO/Virgo/KAGRA S231118d: Updated Sky localization and Source Classification
  85. GRB 231118A: VZLUSAT-2 detection
  86. GRB 231117A: AMI-LA radio observations
  87. GRB 231118A: Swift-BAT refined analysis
  88. Konus-Wind detection of GRB 231020A
  89. GRB 231117A: LDT Confirmation of Optical Fading
  90. GRB 231117A: Wendelstein Confirmation of Fading of the Optical Afterglow
  91. GRB 231118B: CALET Gamma-Ray Burst Monitor detection
  92. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  93. 231118A: Swift-UVOT Detection
  94. GRB231117A: Swift-UVOT detection
  95. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  96. GRB 231118B: Fermi GBM observation
  97. GRB 231118A: Fermi GBM observation
  98. GRB 231118A: MeerLICHT afterglow detection
  99. GRB 231117A: OHP/T120 optical observations
  100. GRB 231118A: VLT/X-shooter redshift

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