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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"

36342 results found.

  1. GRB 240912A: Swift-BAT refined analysis
  2. IPN triangulation of GRB 240913C / EP 240913a
  3. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  4. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  5. GRB 240916A: Fermi GBM Observation
  6. GRB 240821A: radio observation with the VLA
  7. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  8. GRB 240916A: Swift-XRT afterglow detection
  9. GRB 240916A: Swift ToO observations
  10. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  11. GRB 240916B: Fermi GBM Final Real-time Localization
  12. GRB 240914B: Fermi GBM Final Localization
  13. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  14. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  15. GRB 240916A: Fermi GBM Final Real-time Localization
  16. Fermi Gamma-ray Burst Monitor trigger 748124309/240915846 is not a GRB
  17. EP240913a/GRB 240913C: KAIT optical upper limit
  18. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  19. GRB 240913C: Fermi GBM detection
  20. GRB 240914A: Swift-XRT observations
  21. GRB 240913C: Joint location by ETJASMIN
  22. GRB 240914B: AstroSat CZTI detection
  23. EP240913A / GRB 240913C: AstroSat CZTI detection
  24. GRB 240914A: SVOM/GRM observation
  25. GRB 240910A: SVOM/VT optical observations
  26. GRB 240914A: Swift ToO observations
  27. EP240913a: ESO-NTT optical observations
  28. GRB 240914A: ESO-NTT optical observations
  29. EP240913a: Swift/XRT detection of an X-ray source within the EP/WXT error circle
  30. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  31. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  32. GRB 240905E: further NOT optical observations
  33. EP240913a: A GRB Event
  34. GRB 240913B: Fermi GBM Final Real-time Localization
  35. GRB 240911A: LCO optical observations
  36. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  37. Fermi Gamma-ray Burst Monitor trigger 747837485/240912526 is not a GRB
  38. GRB 240912A: Swift/UVOT Detection
  39. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  40. GRB 240912A: SVOM/GRM observation
  41. GRB 240911A: Swift-XRT observations
  42. Fermi GRB 240913A: Global MASTER-Net observations report
  43. GRB 240913A: Fermi GBM Final Real-time Localization
  44. GRB 240912A: J-band observations with WINTER
  45. GRB 240912A: Swift-XRT refined Analysis
  46. GRB 240912A: Fermi GBM Observation
  47. Swift GRB 240912A: Global MASTER-Net observations report
  48. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  49. GRB 240911A: Tiled Swift observations
  50. Fermi Gamma-ray Burst Monitor trigger 747839931/240912555 is not a GRB
  51. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  52. GRB 240912B: Fermi GBM Final Real-time Localization
  53. GRB 240912A: NOT optical spectroscopy
  54. GRB 240912A: Enhanced Swift-XRT position
  55. GRB 240912A: Redshift from OSIRIS+/GTC
  56. GRB 240910A: Redshift from OSIRIS+/GTC
  57. GRB 240912A: Swift detection of a burst with an optical counterpart
  58. GRB 240912A: Fermi GBM Final Real-time Localization
  59. GRB 240910A: Fermi GBM Observation
  60. GRB 240910A: NOT optical observations
  61. GRB 240911A : a likely weak GRB detected by SVOM/ECLAIRs
  62. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  63. GRB 240910A: JinShan optical observations
  64. GRB 240910A: GOTO candidate optical counterpart
  65. GRB 240710A: SVOM/GRM observation
  66. GRB 240910A: Swift ToO observations
  67. IPN triangulation of GRB 240905B (short)
  68. GRB 240825A: 7DT Optical Upper Limit
  69. GRB 240905E: SVOM/VT optical observations
  70. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  71. GRB 240910A: GRBAlpha detection
  72. GRB 240910B: Fermi GBM Final Real-time Localization
  73. GRB 240910A: SVOM/GRM observation
  74. EP240908a: Mondy and AbAO follow-up observations
  75. Fermi GRB 240910A: Global MASTER-Net observations report
  76. GRB 240910A: Fermi GBM Final Real-time Localization
  77. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  78. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  79. GRB 240905B: Fermi GBM Observation
  80. GRB 240905B: GOTO optical upper limits
  81. Fermi GRB 240908A: Global MASTER-Net observations report
  82. GRB 240908A: Fermi GBM Final Real-time Localization
  83. GRB 240801A: SVOM/GRM observation
  84. GRB 240905E: GIT optical upper limit
  85. GRB 240905B: Swift-XRT observations
  86. GRB 240905E: Gaoyazi/GOT optical upper limits
  87. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  88. GRB 240905B: Fermi-LAT detection
  89. GRB 240905B: Swift ToO observations
  90. GRB 240905E: J-band observations with WINTER
  91. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  92. GRB 240905E: AKO Optical Upper Limit
  93. GRB 240905E: SVOM/C-GFT optical upper limit
  94. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  95. Fermi GRB 240905D: Global MASTER-Net observations report
  96. Fermi GRB 240905A: Global MASTER-Net observations report
  97. GRB 240905E: NOT optical upper limits
  98. GRB 240905E: REM optical/NIR upper limits
  99. GRB 240902B: AstroSat CZTI detection of a long burst
  100. GRB 240905E: Swift-XRT refined Analysis

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