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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"

36404 results found.

  1. GRB 241001A: Swift ToO observations
  2. GRB 240930B: GRBAlpha detection
  3. GRB 240929A: GRBAlpha detection
  4. EP240930a : KAIT optical upper limit
  5. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  6. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  7. EP240930a: EP-FXT follow-up observation update
  8. EP240930a: GOTO optical upper limits
  9. GRB 240929A: SVOM/GRM observation
  10. EP240930a: EP-WXT detection of a fast X-ray transient
  11. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  12. GRB 240929A : Leavitt Observatory optical upper limit
  13. Fermi GRB 240930B: Global MASTER-Net observations report
  14. GRB 240930B: Fermi GBM Final Real-time Localization
  15. IPN triangulation of GRB 240926A
  16. GRB 240825A: LBT optical observations
  17. GRB 240928A: SVOM/GRM observation
  18. Fermi GRB 240930A: Global MASTER-Net observations report
  19. Fermi Gamma-ray Burst Monitor trigger 749362078/240930172 (GRB 240930A) is not a GRB
  20. GRB 240930A: Fermi GBM Final Real-time Localization
  21. Fermi Gamma-ray Burst Monitor trigger 749339671/240929913 is not a GRB
  22. GRB 240929A long GRB detected by INTEGRAL
  23. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  24. Fermi GRB 240929A: Global MASTER-Net observations report
  25. GRB 240929A: Fermi GBM Final Real-time Localization
  26. Konus-Wind detection of GRB 240912A
  27. Swift Trigger 1256950 is probably not a GRB
  28. Fermi Gamma-ray Burst Monitor trigger 749191601/240928199 is not a GRB
  29. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  30. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  31. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  32. EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
  33. GRB 240926A: SVOM/GRM observation
  34. Konus-Wind detection of GRB 240905B
  35. GRB 240529A: FRAM-ORM early optical afterglow observations reveal plateau and rebrightening
  36. EP240919a / GRB 240919A: SVOM/VT upper limit
  37. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  38. Konus-Wind detection of GRB 240918B
  39. IPN triangulation of GRB 240918B
  40. GRB 240905B: VZLUSAT-2 detection
  41. GRB 240918B: AstroSat CZTI detection
  42. EP240913A/GRB 240913C: AbAO optical upper limit
  43. EP240919a / GRB 240919A: Mondy optical upper limit
  44. EP240913a/GRB 240913C: 1.6m Mephisto observations
  45. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  46. EP240919a / GRB 240919A: REM optical and NIR upper limits
  47. EP240919a / GRB 240919A: KAIT optical upper limit
  48. GRB 240414A: further radio observations with the VLA
  49. GRB 240919A / EP240919a: SVOM/GRM observation
  50. GRB 240910A: radio detection with the VLA
  51. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  52. EP240919a is likely a GRB event (duplicate submission of 37563)
  53. EP240919a is likely a GRB event
  54. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  55. GRB 240918B: Fermi GBM Detection
  56. GRB 240910A: further Swift observations and confirmation of afterglow
  57. Fermi GRB 240918A: Global MASTER-Net observations report
  58. GRB 240918A: Fermi GBM Final Real-time Localization
  59. EP240918a: YAHPT Optical Upper Limit
  60. GRB 240916A: GRBAlpha detection
  61. GRB 240914B: GRBAlpha detection
  62. GRB 240916A: NOT optical observation
  63. GRB 240912A: Swift-BAT refined analysis
  64. IPN triangulation of GRB 240913C / EP 240913a
  65. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  66. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  67. GRB 240916A: Fermi GBM Observation
  68. GRB 240821A: radio observation with the VLA
  69. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  70. GRB 240916A: Swift-XRT afterglow detection
  71. GRB 240916A: Swift ToO observations
  72. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  73. GRB 240916B: Fermi GBM Final Real-time Localization
  74. GRB 240914B: Fermi GBM Final Localization
  75. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  76. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  77. GRB 240916A: Fermi GBM Final Real-time Localization
  78. Fermi Gamma-ray Burst Monitor trigger 748124309/240915846 is not a GRB
  79. EP240913a/GRB 240913C: KAIT optical upper limit
  80. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  81. GRB 240913C: Fermi GBM detection
  82. GRB 240914A: Swift-XRT observations
  83. GRB 240913C: Joint location by ETJASMIN
  84. GRB 240914B: AstroSat CZTI detection
  85. EP240913A / GRB 240913C: AstroSat CZTI detection
  86. GRB 240914A: SVOM/GRM observation
  87. GRB 240910A: SVOM/VT optical observations
  88. GRB 240914A: Swift ToO observations
  89. EP240913a: ESO-NTT optical observations
  90. GRB 240914A: ESO-NTT optical observations
  91. EP240913a: Swift/XRT detection of an X-ray source within the EP/WXT error circle
  92. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  93. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  94. GRB 240905E: further NOT optical observations
  95. EP240913a: A GRB Event
  96. GRB 240913B: Fermi GBM Final Real-time Localization
  97. GRB 240911A: LCO optical observations
  98. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  99. Fermi Gamma-ray Burst Monitor trigger 747837485/240912526 is not a GRB
  100. GRB 240912A: Swift/UVOT Detection

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