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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"

32689 results found.

  1. GRB 231215A: radio detection with the VLA
  2. GRB 230818A: further radio observations with the VLA
  3. GRB 230812B: further radio observations with the VLA
  4. GRB 240107A: AstroSat CZTI detection
  5. LIGO/Virgo/KAGRA S240109a: Identification of a GW compact binary merger candidate
  6. IceCube-240105A: JCMT SCUBA2 Detection of Two Bright Submillimeter Sources
  7. Update of IceCube-240105A - Corrected errors
  8. GRB 240106A: GRBAlpha detection
  9. LIGO/Virgo/KAGRA S240107b: Updated Sky localization and Source Classification
  10. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  11. IPN triangulation of GRB 240101C (short)
  12. GRB GRB240101C: Fermi GBM observation
  13. GRB 240101A: 1.3m DFOT optical observations
  14. GRB 240102A: 1.3m DFOT optical upper limit
  15. GRB 240101B: 1.3m DFOT optical upper limit
  16. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  17. LIGO/Virgo/KAGRA S240104bl: Updated Sky localization
  18. LIGO/Virgo/KAGRA S240104bl: Identification of a GW compact binary merger candidate
  19. GRB 240101C: AstroSat CZTI detection
  20. GRB 231220A: Swift-UVOT upper limit
  21. GRB 240102A: Swift-BAT refined analysis
  22. GRB 240102A: Swift/UVOT Upper Limits
  23. GRB 231230A: Swift-BAT refined analysis
  24. GRB 240101A: Swift-BAT refined analysis
  25. GRB 240101B: Swift-BAT refined analysis
  26. GRB 240102B (Fermi GBM trigger 725926335/240102925) is not a GRB
  27. GRB 240102A: LCOGT Optical Upper Limits
  28. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  29. GRB 240101A: Terskol Zeiss-2000 optical observations
  30. GRB 240101C: GRBAlpha detection
  31. GRB 240101B: Swift/UVOT Upper Limits
  32. GRB 240101A: Swift/UVOT Upper Limits
  33. GRB 240101B: KAIT Optical Upper Limit
  34. GRB 240101A: KAIT Optical Upper Limit
  35. LIGO/Virgo/KAGRA S231231ag: Updated Sky localization and Source Classification
  36. LIGO/Virgo/KAGRA S231231ag: Identification of a GW compact binary merger candidate
  37. GRB231230A: Fermi GBM Observation
  38. GRB 231230A: GOTO optical upper limits
  39. GRB 231230A: Swift/UVOT Upper Limits
  40. GRB 231230A: NOT optical upper limits
  41. IPN triangulation of GRB 231224A (short)
  42. LIGO/Virgo/KAGRA S231226av: Updated Sky localization
  43. LIGO/Virgo/KAGRA S231226av: Identification of a GW compact binary merger candidate
  44. GRB 231222B: GRBAlpha detection
  45. LIGO/Virgo/KAGRA S231224e: Updated Sky localization and Source Classification
  46. LIGO/Virgo/KAGRA S231224e: Identification of a GW compact binary merger candidate
  47. LIGO/Virgo/KAGRA S231223j: Updated Sky localization
  48. GRB 231222B: Swift-XRT afterglow detection
  49. LIGO/Virgo/KAGRA S231223j: Identification of a GW compact binary merger candidate
  50. GRB 231222B: Fermi GBM Detection
  51. GRB 231222A: Tiled Swift observations
  52. IceCube-231211A: GRANDMA observations of PKS2047+098
  53. GRID detection of GRB 231215A
  54. GRB 231220A: Swift-XRT follow-up observations
  55. GRB 231220A: Swift ToO observations
  56. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  57. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  58. GRID detection of GRB 231205B
  59. GRID detection of GRB 231205A
  60. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  61. GRB 231214B: Fermi GBM observation
  62. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  63. GRB 231215A: AMI-LA radio detection
  64. GRB 231216A: Nanshan/HMT optical upper limit
  65. GRB 231216A: LCOGT Optical Upper Limits
  66. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  67. GRB 231216A: Swift-XRT refined analysis correction
  68. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  69. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  70. GRB 231216A: REM NIR upper limits
  71. GRB 231216A: Swift/UVOT Upper Limits
  72. GRB 231216A: Swift-BAT refined analysis
  73. GRB 231215A: Swift-BAT refined analysis
  74. GRB 231214A: Swift-BAT refined analysis
  75. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  76. GRB 231216A: GIT optical upper limit
  77. GRB 231216A: NOT optical upper limits
  78. GRB 231215A: GRBAlpha detection
  79. Konus-Wind detection of GRB 231215A
  80. GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
  81. GRB 231215A: NOT optical observations
  82. GRB 231214A: Swift/UVOT Upper Limits
  83. GRB 231215A: Redshift from OSIRIS+ / GTC
  84. GRB 231205B: VZLUSAT-2 detection
  85. GRB 231204A: VZLUSAT-2 detection
  86. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  87. GRB 231215A: Fermi GBM observation
  88. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  89. GRB 231215A : OHP/T193 optical afterglow detection
  90. GRB 231215A: Swift/UVOT Detection
  91. GRB 231215A: AKO Optical Upper Limit
  92. GRB 231215A: AGILE detection
  93. GRB 231214A: Fermi GBM observation
  94. Konus-Wind detection of GRB 231210B
  95. ATCA observations of GRB 231210B
  96. GRB 231214A: REM optical/NIR upper limits
  97. GRB 231215A: GROWTH-India optical follow-up
  98. GRB 231215A : Nanshan/HMT optical observations
  99. GRB 231215A: AstroSat CZTI detection
  100. GRB 231215A : MITSuME Akeno optical afterglow candidate detection

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