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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"

32770 results found.

  1. IPN triangulation of GRB 231205A
  2. GRB 231205B: Swift-BAT refined analysis
  3. GRB 231205B: 1.3m DFOT Optical upper limit
  4. LIGO/Virgo/KAGRA S231206cc: Updated Sky localization and Source Classification
  5. GRB 231206A: joint location of multiple instruments by ETJASMIN
  6. GRB 231205B: optical upper limit in TSHAOand AbAO
  7. LIGO/Virgo/KAGRA S231206cc: Identification of a GW compact binary merger candidate
  8. LIGO/Virgo/KAGRA S231206ca: Identification of a GW compact binary merger candidate
  9. GRB231115A: TURBO Pre-Burst Optical Upper Limits
  10. GRB 231205B: AGILE detection
  11. Fermi-LAT gamma-ray observations of IceCube-231202A
  12. GRB 231205B: REM optical/NIR upper limits
  13. GRB 231129C: ASIM MXGS observation and localization
  14. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  15. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  16. GRB 231206A: GECAM-B detection of a short burst (correction)
  17. GRB 231205B : MITSuME Akeno optical upper limits
  18. GRB 231205B: Zadko observatory - Gingin optical observations
  19. GRB 231205B: Gaoyazi/GOT optical upper limit
  20. GRB 231205B: Nanshan/HMT optical upper limit
  21. GRB 231205B: GECAM-B detection of a long burst
  22. GRB 231205B: LCOGT Optical Upper Limits
  23. GRB 231205A: DDOTI Upper Limits on the Afterglow
  24. GRB 231204A: Glowbug gamma-ray detection
  25. GRB 231204A: CALET Gamma-Ray Burst Monitor detection
  26. GRB 231205B: AKO Optical Upper Limit
  27. GRB 231205A: joint location of multiple instruments by ETJASMIN
  28. GRB 231204A: AstroSat CZTI detection
  29. GRB 231205A: GECAM-B detection of a short burst
  30. IceCube-231202A: Upper limits from a search for additional neutrino events in IceCube
  31. GRB 231203A: Fermi GBM Observation
  32. Konus-Wind detection of GRB 231129C
  33. GRB 231129C: PROMPT optical upper limits for the MAXI/GSC X-ray counterpart and the MASTER afterglow candidate
  34. GRB 231129A: VZLUSAT-2 detection
  35. GRB 231128A: VZLUSAT-2 detection
  36. Optical transient in the field of Messier 31, likely a new blazar: back to bright state
  37. GRB 231129C: AGILE detection
  38. GRB 231129A : MITSuME Akeno optical upper limits
  39. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  40. GRB 231129A: Swift-BAT refined analysis
  41. GRB 231129C: MASTER OT detection
  42. GRB 231129C: Fermi-LAT detection
  43. GRB 231129A: JinShan optical upper limit
  44. GRB 231129C: GRBAlpha detection
  45. GRB 231129C: Glowbug gamma-ray detection
  46. GRB 231129A: Swift/UVOT Upper Limits
  47. GRB 231129A: optical upper limit in Mondy observatory
  48. GRB 231129C: GECAM-B detection of a bright burst
  49. GRB 231129C: AstroSat CZTI detection
  50. GRB 231129C: iTelescope OT retraction
  51. GRB 231129C: CALET Gamma-Ray Burst Monitor detection
  52. GRB 231129C: Fermi GBM Observation of a very bright GRB
  53. GRB 231129C: iTelescope likely optical afterglow AT 2023yph discovery
  54. GRB 231129C: Tiled Swift observations
  55. GRB 231127A: GRBAlpha detection
  56. LIGO/Virgo/KAGRA S231129ac: Updated Sky localization
  57. GRB 231129B: Tiled Swift observations
  58. Fermi-LAT gamma-ray observations of IceCube-231125A
  59. LIGO/Virgo/KAGRA S231129ac: Identification of a GW compact binary merger candidate
  60. GRB 231129A: GECAM-C detection of a long burst
  61. GRB 231129A: INTEGRAL detection of a long GRB
  62. LIGO/Virgo/KAGRA S231127cg: Updated Sky localization
  63. GRB 231123C: Fermi GBM Observation
  64. GRB 231123B: Fermi GBM Observation
  65. IceCube-231125A: Upper limits from a search for additional neutrino events in IceCube
  66. LIGO/Virgo/KAGRA S231127cg: Identification of a GW compact binary merger candidate
  67. GRB 231117A: MeerKAT 1.3GHz detection
  68. GRB 231127A: CALET Gamma-Ray Burst Monitor detection
  69. GRB 231125A: GRBAlpha detection
  70. GRB 231125A: CALET Gamma-Ray Burst Monitor detection
  71. GRB 231125A (short): Glowbug gamma-ray detection
  72. Update of IceCube-231125A - Corrected errors
  73. GRB 231124A: GRBAlpha detection
  74. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  75. GRB 231123C: Insight-HXMT/HE detection
  76. GRB 231123C (short): Glowbug gamma-ray detection
  77. GRB 231124A: Glowbug gamma-ray detection
  78. GRB230728A: VIRT optical upper limit
  79. GRB230506C: VIRT optical upper limit
  80. GRB230506B: VIRT optical upper limit
  81. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  82. LIGO/Virgo/KAGRA S231118an: Updated Sky localization and EM Bright Classification
  83. GRB 231124A: CALET Gamma-Ray Burst Monitor detection
  84. GRB 231115A: XMM-Newton observation
  85. GRB 231123A: AstroSat CZTI detection
  86. GRB 231117A: Mondy optical observations
  87. LIGO/Virgo/KAGRA S231123cg: Identification of a GW compact binary merger candidate
  88. GRB 231118A: REM optical afterglow detection
  89. GRB 231122B: AstroSat CZTI detection
  90. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  91. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  92. GRB 231117A: Chandra afterglow detection
  93. GRB 231122B: Glowbug gamma-ray detection
  94. GRB 231117A: Continued GTC Observations
  95. GRB 231122A: GECAM detection
  96. GRB 231118A: ATCA detection of radio counterpart
  97. GRB 231117A: Swift/UVOT late time observations
  98. GRB 231117A: GTC Near-Infrared Observations
  99. GRB 231117A: Swift-BAT refined analysis
  100. GRB 231118A: GRBAlpha detection

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