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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

37774 results found.

  1. GRID detection of GRB 231205A
  2. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  3. GRB 231214B: Fermi GBM observation
  4. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  5. GRB 231216A: 10.4 m GTC optical upper limit
  6. GRB 231215A: AMI-LA radio detection
  7. GRB 231216A: Nanshan/HMT optical upper limit
  8. GRB 231216A: LCOGT Optical Upper Limits
  9. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  10. GRB 231216A: Swift-XRT refined analysis correction
  11. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  12. GRB 231216A: Swift-XRT refined Analysis
  13. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  14. GRB 231216A: REM NIR upper limits
  15. GRB 231216A: Swift/UVOT Upper Limits
  16. GRB 231216A: Swift-BAT refined analysis
  17. GRB 231215A: Swift-BAT refined analysis
  18. GRB 231214A: Swift-BAT refined analysis
  19. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  20. GRB 231216A: GIT optical upper limit
  21. GRB 231216A: NOT optical upper limits
  22. GRB 231216A: BOOTES-2/TELMA optical upper limit
  23. GRB 231215A: GRBAlpha detection
  24. GRB 231216A: Swift detection of a burst
  25. Konus-Wind detection of GRB 231215A
  26. GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
  27. GRB 231215A: NOT optical observations
  28. GRB 231214A: Swift/UVOT Upper Limits
  29. GRB 231215A: Redshift from OSIRIS+ / GTC
  30. GRB 231205B: VZLUSAT-2 detection
  31. GRB 231204A: VZLUSAT-2 detection
  32. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  33. GRB 231215A: Fermi GBM observation
  34. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  35. GRB 231215A : OHP/T193 optical afterglow detection
  36. GRB 231215A: Swift/UVOT Detection
  37. GRB 231215A: Swift-XRT refined Analysis
  38. GRB 231215A: BOOTES-4/MET optical detection
  39. GRB 231215A: AKO Optical Upper Limit
  40. GRB 231215A: AGILE detection
  41. GRB 231214A: Fermi GBM observation
  42. Konus-Wind detection of GRB 231210B
  43. ATCA observations of GRB 231210B
  44. GRB 231215A: Enhanced Swift-XRT position
  45. Fermi trigger No 724326442: Global MASTER-Net observations report
  46. GRB 231214A: REM optical/NIR upper limits
  47. GRB 231215A: GROWTH-India optical follow-up
  48. GRB 231215A : Nanshan/HMT optical observations
  49. GRB 231215A: AstroSat CZTI detection
  50. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  51. GRB 231214A: Swift-XRT refined Analysis
  52. GRB 231215A: Mondy optical bright afterglow detection
  53. GRB 231214A: AstroSat CZTI detection
  54. GRB 231215C: MASTER OT detection
  55. GRB 231215A: Swift-XRT observations
  56. GRB 231215B: Fermi GBM Final Real-time Localization
  57. GRB 231215A: Swift detection of a burst
  58. GRB 231214A: Fermi-LAT detection
  59. GRB 231214A: Enhanced Swift-XRT position
  60. GRB 231214B: Swift/BAT-GUANO detection of a burst
  61. GRB231214A: BOOTES-6/DPRT optical upper limit
  62. Fermi trigger No 724278269: Global MASTER-Net observations report
  63. Fermi trigger No 724233240: Global MASTER-Net observations report
  64. GRB 231214A: Swift detection of a burst
  65. GRB 231214A: Fermi GBM Final Real-time Localization
  66. GRB 231210B: REM optical/NIR upper limits
  67. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 2047+098, located inside the IceCube-231211A error region
  68. IceCube-231211A - IceCube observation of a high-energy neutrino candidate track-like event
  69. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  70. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  71. GRB 231212A: GECAM-C detection of a likely short burst
  72. Fermi trigger No 724035412: Global MASTER-Net observations report
  73. GRB 231210B: MeerLICHT afterglow observations
  74. GRB 231210B: Swift-BAT refined analysis
  75. GRB 231210B: Swift-XRT refined Analysis
  76. GRB 231210B: Enhanced Swift-XRT position
  77. GRB 231210B: VLT/X-shooter redshift
  78. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  79. Fermi trigger No 723906955: Global MASTER-Net observations report
  80. GRB 231210B: Swift detection of a burst with optical counterpart
  81. IPN triangulation of GRB 231129C
  82. GRB 231210A: Fermi GBM Final Real-time Localization
  83. GRB 231208A: GRBAlpha detection
  84. GRB231205B: Swift/UVOT Upper Limits
  85. GRB 231208A: Glowbug gamma-ray detection
  86. GRB 231208A: AstroSat CZTI detection of a faint burst
  87. IPN triangulation of GRB 231205A
  88. GRB 231205B: Swift-BAT refined analysis
  89. GRB 231205B: 1.3m DFOT Optical upper limit
  90. GRB 231206A: joint location of multiple instruments by ETJASMIN
  91. GRB 231205B: optical upper limit in TSHAOand AbAO
  92. GRB231115A: TURBO Pre-Burst Optical Upper Limits
  93. GRB 231205B: AGILE detection
  94. Fermi trigger No 723581802: Global MASTER-Net observations report
  95. GRB 231206B: Fermi GBM Final Real-time Localization
  96. GRB 231205B: Ondrejov D50 optical upper limit
  97. GRB 231205B: Swift-XRT refined Analysis
  98. Fermi-LAT gamma-ray observations of IceCube-231202A
  99. GRB 231205B: REM optical/NIR upper limits
  100. GRB 231129C: ASIM MXGS observation and localization

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