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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"

32793 results found.

  1. GRB230728A: VIRT optical upper limit
  2. GRB230506C: VIRT optical upper limit
  3. GRB230506B: VIRT optical upper limit
  4. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  5. LIGO/Virgo/KAGRA S231118an: Updated Sky localization and EM Bright Classification
  6. GRB 231124A: CALET Gamma-Ray Burst Monitor detection
  7. GRB 231115A: XMM-Newton observation
  8. GRB 231123A: AstroSat CZTI detection
  9. GRB 231117A: Mondy optical observations
  10. LIGO/Virgo/KAGRA S231123cg: Identification of a GW compact binary merger candidate
  11. GRB 231118A: REM optical afterglow detection
  12. GRB 231122B: AstroSat CZTI detection
  13. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  14. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  15. GRB 231117A: Chandra afterglow detection
  16. GRB 231122B: Glowbug gamma-ray detection
  17. GRB 231117A: Continued GTC Observations
  18. GRB 231122A: GECAM detection
  19. GRB 231118A: ATCA detection of radio counterpart
  20. GRB 231117A: Swift/UVOT late time observations
  21. GRB 231117A: GTC Near-Infrared Observations
  22. GRB 231117A: Swift-BAT refined analysis
  23. GRB 231118A: GRBAlpha detection
  24. LIGO/Virgo/KAGRA S231119u: Updated Sky localization and Source Classification
  25. LIGO/Virgo/KAGRA S231118ab: Updated Sky localization and Source Classification
  26. LIGO/Virgo/KAGRA S231118d: Updated Sky localization and Source Classification
  27. GRB 231118A: VZLUSAT-2 detection
  28. GRB 231117A: AMI-LA radio observations
  29. GRB 231118A: Swift-BAT refined analysis
  30. Konus-Wind detection of GRB 231020A
  31. GRB 231117A: LDT Confirmation of Optical Fading
  32. GRB 231117A: Wendelstein Confirmation of Fading of the Optical Afterglow
  33. GRB 231118B: CALET Gamma-Ray Burst Monitor detection
  34. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  35. 231118A: Swift-UVOT Detection
  36. GRB231117A: Swift-UVOT detection
  37. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  38. GRB 231118B: Fermi GBM observation
  39. GRB 231118A: Fermi GBM observation
  40. GRB 231118A: MeerLICHT afterglow detection
  41. GRB 231117A: OHP/T120 optical observations
  42. GRB 231118A: VLT/X-shooter redshift
  43. GRB 231117A: Pan-STARRS1 follow-up confirms rapid fading
  44. LIGO/Virgo/KAGRA S231119u: Identification of a GW compact binary merger candidate
  45. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  46. GRB 231117A: AKO Follow-Up Observation
  47. GRB 231117A: GECAM-C detection
  48. GRB 231118A: AstroSat CZTI detection
  49. GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
  50. GRB 231117A: 10 GHz VLA detection
  51. GRB 231118A: Las Cumbres optical detection
  52. GRB 231118A: LCOGT Optical Observations
  53. GRB 231118A: MASTER OT observation
  54. GRB 231118A: Continued Skynet Observations
  55. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  56. GRB 231117A: SOAR/Goodman imaging of the afterglow
  57. GRB 231117A: Lowell Discovery Telescope Observations
  58. GRB 231117A: ePESSTO+ host galaxy redshift confirmation
  59. GRB 231117A: ATCA detection of a radio counterpart
  60. LIGO/Virgo/KAGRA S231118an: Identification of a GW compact binary merger candidate
  61. GRB 231117A: GRBAlpha detection
  62. LIGO/Virgo/KAGRA S231118ab: Identification of a GW compact binary merger candidate
  63. GRB 231117A: Keck spectroscopy of afterglow candidate
  64. GRB 231115A: Wendelstein Optical/Infrared Observations
  65. GRB 231115A: JinShan optical upper limits
  66. LIGO/Virgo/KAGRA S231118d: Identification of a GW compact binary merger candidate
  67. GRB 231117A: GIT optical follow-up
  68. GRB 231117A: LT observations consistent with fading
  69. GRB 231117A: Keck observations indicate presence of optical afterglow in z~0.3-0.5 galaxy
  70. GRB 231117A: REM optical and NIR early-time observations
  71. GRB 231117A: AKO Optical Upper Limit
  72. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  73. Swift GRB 231117A: Global MASTER-Net observations report
  74. GRB 231117A (short): Glowbug gamma-ray detection
  75. GRB 231117A: ATLAS non-detection of an optical counterpart
  76. Konus-Wind detection of GRB 231117A (short/hard)
  77. GRB 231115A : OHP/T120 optical upper limit
  78. GRB 231115A: optical observations from INAF observatories
  79. GRB 231117A : MITSuME Akeno optical upper limits
  80. GRB 231117A: AGILE detection of a bright short burst
  81. GRB 231117A: GOTO optical upper limits
  82. GRB 231117A: AstroSat CZTI detection of a bright short burst
  83. GRB 231115A: Non-detection of radio emission with CHIME/FRB
  84. GRB 231111A: Swift/UVOT Detection
  85. MAGIC observation of GRB 231115A, a possible magnetar giant flare
  86. GRB231115A: Liverpool Telescope imaging
  87. GRB 231115A: NuSTAR Follow-Up Observations
  88. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  89. GRB 231115A: Swift-XRT and Swift-UVOT observations
  90. Fermi GRB 231116A: Global MASTER-Net observations report
  91. Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
  92. GRB 231115A: AGILE/MCAL upper limits
  93. GRB 231115A: Insight-HXMT/HE detection
  94. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  95. GRB 231115A : MITSuME Akeno and Okayama optical upper limits
  96. GRB 231115A: Gaoyazi/GOT follow-up and archival observations
  97. GRB 231115A / AT2023xvj: Updated GIT analysis
  98. GRB 231115A: archival Chandra X-ray observations
  99. GRB 231115A: Upper limits from a neutrino search with IceCube
  100. GRB 231115A: Kinder observations with Lulin observatory

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