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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"

23706 results found.

  1. EP EP240918a: Global MASTER-Net observations report
  2. EP240918a: Optical upper limits with Kinder observations
  3. EP240918a: GMG Optical Upper Limit
  4. GRB 240916A: GRBAlpha detection
  5. GRB 240914B: GRBAlpha detection
  6. EP240918a: an X-ray transient detected by Einstein Probe
  7. GRB 240916A: NOT optical observation
  8. GRB 240912A: Swift-BAT refined analysis
  9. IPN triangulation of GRB 240913C / EP 240913a
  10. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  11. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  12. GRB 240821A: radio observation with the VLA
  13. GRB 240916A: Swift-XRT afterglow detection
  14. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  15. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  16. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  17. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  18. EP EP240913a: Global MASTER-Net observations report
  19. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  20. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  21. EP240913a/GRB 240913C: KAIT optical upper limit
  22. GRB 240913C: Fermi GBM detection
  23. GRB 240910A: SVOM/VT optical observations
  24. EP240913a: NOT optical upper limits
  25. EP240913a: ESO-NTT optical observations
  26. GRB 240914A: ESO-NTT optical observations
  27. GRB 240905E: further NOT optical observations
  28. EP240913a: A GRB Event
  29. EP240913a: EP-WXT detection of a fast X-ray transient
  30. GRB 240911A: LCO optical observations
  31. GRB 240912A: Swift/UVOT Detection
  32. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  33. Fermi trigger No 747920561: Global MASTER-Net observations report
  34. GRB 240911A: Swift-XRT observations
  35. Fermi GRB 240913A: Global MASTER-Net observations report
  36. GRB 240912A: J-band observations with WINTER
  37. GRB 240912A: Swift-XRT refined Analysis
  38. Swift GRB 240912A: Global MASTER-Net observations report
  39. GRB 240912A: NOT optical spectroscopy
  40. GRB 240912A: Redshift from OSIRIS+/GTC
  41. GRB 240910A: Redshift from OSIRIS+/GTC
  42. GRB 240912A: Swift detection of a burst with an optical counterpart
  43. GRB 240910A: Fermi GBM Observation
  44. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  45. GRB 240910A: GOTO candidate optical counterpart
  46. EP240908a: Optical afterglow confirmation
  47. IPN triangulation of GRB 240905B (short)
  48. GRB 240905E: SVOM/VT optical observations
  49. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  50. GRB 240910A: GRBAlpha detection
  51. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  52. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  53. EP240908a: Mondy and AbAO follow-up observations
  54. Fermi GRB 240910A: Global MASTER-Net observations report
  55. EP240908a: optical afterglow candidate
  56. EP EP240908a: Global MASTER-Net observations report
  57. Fermi trigger No 747553301: Global MASTER-Net observations report
  58. EP240908a: TRT optical upper limit
  59. GRB 240905B: GOTO optical upper limits
  60. EP240908a: EP detection of a fast X-ray transient
  61. Fermi GRB 240908A: Global MASTER-Net observations report
  62. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  63. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  64. GRB 240905B: Swift-XRT observations
  65. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  66. GRB 240905E: J-band observations with WINTER
  67. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  68. Fermi GRB 240905D: Global MASTER-Net observations report
  69. Fermi GRB 240905A: Global MASTER-Net observations report
  70. GRB 240905E: NOT optical upper limits
  71. GRB 240905E: REM optical/NIR upper limits
  72. GRB 240902B: AstroSat CZTI detection of a long burst
  73. GRB 240905E: Swift-XRT refined Analysis
  74. GRB 240825A: Montarrenti Observatory optical follow-up observations
  75. Swift GRB 240905E: Global MASTER-Net observations report
  76. GRB 240905E: Swift detection of a burst
  77. Fermi GRB 240905B: Global MASTER-Net observations report
  78. Swift GRB 240904A: Global MASTER-Net observations report
  79. Fermi trigger No 747163821: Global MASTER-Net observations report
  80. GRB 240904A: Swift detection of a burst
  81. GRB 240828A: GECAM detection
  82. GRB 240825A: MeerLICHT afterglow detection
  83. Fermi trigger No 746923430: Global MASTER-Net observations report
  84. GRB 240828A: SAO RAS AS-500(2) optical observations
  85. GRB 240821A: VLT spectroscopic observations
  86. Fermi trigger No 746882332: Global MASTER-Net observations report
  87. GRB 240829B: GRBAlpha detection
  88. GRB240828B: REM optical/NIR upper limits
  89. Fermi trigger No 746816563: Global MASTER-Net observations report
  90. GRB 240828B: GRANDMA Optical Upper Limit
  91. LIGO/Virgo/KAGRA S240830gn: Coverage and upper limits from MAXI/GSC observations
  92. GRB 240829A: Swift-BAT refined analysis
  93. GRB 240825A: Swift-BAT refined analysis
  94. GRB 240828B: J-band upper limit from WINTER
  95. Fermi trigger No 746684112: Global MASTER-Net observations report
  96. GRB 240828B: GMG Optical Upper Limit
  97. GRB 240828A: KAIT continued optical observations
  98. GRB 240828B: KAIT optical upper limit
  99. Fermi trigger No 746587425: Global MASTER-Net observations report
  100. GRB 240629A: First GRB Detected by BurstCube

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