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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"

32769 results found.

  1. GRB 231205B: Swift-BAT refined analysis
  2. GRB 231205B: 1.3m DFOT Optical upper limit
  3. LIGO/Virgo/KAGRA S231206cc: Updated Sky localization and Source Classification
  4. GRB 231206A: joint location of multiple instruments by ETJASMIN
  5. GRB 231205B: optical upper limit in TSHAOand AbAO
  6. LIGO/Virgo/KAGRA S231206cc: Identification of a GW compact binary merger candidate
  7. LIGO/Virgo/KAGRA S231206ca: Identification of a GW compact binary merger candidate
  8. GRB231115A: TURBO Pre-Burst Optical Upper Limits
  9. GRB 231205B: AGILE detection
  10. Fermi-LAT gamma-ray observations of IceCube-231202A
  11. GRB 231205B: REM optical/NIR upper limits
  12. GRB 231129C: ASIM MXGS observation and localization
  13. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  14. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  15. GRB 231206A: GECAM-B detection of a short burst (correction)
  16. GRB 231205B : MITSuME Akeno optical upper limits
  17. GRB 231205B: Zadko observatory - Gingin optical observations
  18. GRB 231205B: Gaoyazi/GOT optical upper limit
  19. GRB 231205B: Nanshan/HMT optical upper limit
  20. GRB 231205B: GECAM-B detection of a long burst
  21. GRB 231205B: LCOGT Optical Upper Limits
  22. GRB 231205A: DDOTI Upper Limits on the Afterglow
  23. GRB 231204A: Glowbug gamma-ray detection
  24. GRB 231204A: CALET Gamma-Ray Burst Monitor detection
  25. GRB 231205B: AKO Optical Upper Limit
  26. GRB 231205A: joint location of multiple instruments by ETJASMIN
  27. GRB 231204A: AstroSat CZTI detection
  28. GRB 231205A: GECAM-B detection of a short burst
  29. IceCube-231202A: Upper limits from a search for additional neutrino events in IceCube
  30. GRB 231203A: Fermi GBM Observation
  31. Konus-Wind detection of GRB 231129C
  32. GRB 231129C: PROMPT optical upper limits for the MAXI/GSC X-ray counterpart and the MASTER afterglow candidate
  33. GRB 231129A: VZLUSAT-2 detection
  34. GRB 231128A: VZLUSAT-2 detection
  35. Optical transient in the field of Messier 31, likely a new blazar: back to bright state
  36. GRB 231129C: AGILE detection
  37. GRB 231129A : MITSuME Akeno optical upper limits
  38. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  39. GRB 231129A: Swift-BAT refined analysis
  40. GRB 231129C: MASTER OT detection
  41. GRB 231129C: Fermi-LAT detection
  42. GRB 231129A: JinShan optical upper limit
  43. GRB 231129C: GRBAlpha detection
  44. GRB 231129C: Glowbug gamma-ray detection
  45. GRB 231129A: Swift/UVOT Upper Limits
  46. GRB 231129A: optical upper limit in Mondy observatory
  47. GRB 231129C: GECAM-B detection of a bright burst
  48. GRB 231129C: AstroSat CZTI detection
  49. GRB 231129C: iTelescope OT retraction
  50. GRB 231129C: CALET Gamma-Ray Burst Monitor detection
  51. GRB 231129C: Fermi GBM Observation of a very bright GRB
  52. GRB 231129C: iTelescope likely optical afterglow AT 2023yph discovery
  53. GRB 231129C: Tiled Swift observations
  54. GRB 231127A: GRBAlpha detection
  55. LIGO/Virgo/KAGRA S231129ac: Updated Sky localization
  56. GRB 231129B: Tiled Swift observations
  57. Fermi-LAT gamma-ray observations of IceCube-231125A
  58. LIGO/Virgo/KAGRA S231129ac: Identification of a GW compact binary merger candidate
  59. GRB 231129A: GECAM-C detection of a long burst
  60. GRB 231129A: INTEGRAL detection of a long GRB
  61. LIGO/Virgo/KAGRA S231127cg: Updated Sky localization
  62. GRB 231123C: Fermi GBM Observation
  63. GRB 231123B: Fermi GBM Observation
  64. IceCube-231125A: Upper limits from a search for additional neutrino events in IceCube
  65. LIGO/Virgo/KAGRA S231127cg: Identification of a GW compact binary merger candidate
  66. GRB 231117A: MeerKAT 1.3GHz detection
  67. GRB 231127A: CALET Gamma-Ray Burst Monitor detection
  68. GRB 231125A: GRBAlpha detection
  69. GRB 231125A: CALET Gamma-Ray Burst Monitor detection
  70. GRB 231125A (short): Glowbug gamma-ray detection
  71. Update of IceCube-231125A - Corrected errors
  72. GRB 231124A: GRBAlpha detection
  73. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  74. GRB 231123C: Insight-HXMT/HE detection
  75. GRB 231123C (short): Glowbug gamma-ray detection
  76. GRB 231124A: Glowbug gamma-ray detection
  77. GRB230728A: VIRT optical upper limit
  78. GRB230506C: VIRT optical upper limit
  79. GRB230506B: VIRT optical upper limit
  80. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  81. LIGO/Virgo/KAGRA S231118an: Updated Sky localization and EM Bright Classification
  82. GRB 231124A: CALET Gamma-Ray Burst Monitor detection
  83. GRB 231115A: XMM-Newton observation
  84. GRB 231123A: AstroSat CZTI detection
  85. GRB 231117A: Mondy optical observations
  86. LIGO/Virgo/KAGRA S231123cg: Identification of a GW compact binary merger candidate
  87. GRB 231118A: REM optical afterglow detection
  88. GRB 231122B: AstroSat CZTI detection
  89. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  90. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  91. GRB 231117A: Chandra afterglow detection
  92. GRB 231122B: Glowbug gamma-ray detection
  93. GRB 231117A: Continued GTC Observations
  94. GRB 231122A: GECAM detection
  95. GRB 231118A: ATCA detection of radio counterpart
  96. GRB 231117A: Swift/UVOT late time observations
  97. GRB 231117A: GTC Near-Infrared Observations
  98. GRB 231117A: Swift-BAT refined analysis
  99. GRB 231118A: GRBAlpha detection
  100. LIGO/Virgo/KAGRA S231119u: Updated Sky localization and Source Classification

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