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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"

39371 results found.

  1. Fermi GRB 230603A: Global MASTER-Net observations report
  2. Fermi trigger No 707039690: Global MASTER-Net observations report
  3. GRB 230506B: Chandra localization of the X-ray afterglow
  4. ZTF and GIT Observations of the Candidate Optical Afterglow AT2023jxk
  5. GRB 230606A: Swift-BAT refined analysis
  6. GRB 230606A: Gaoyazi/GOT optical upper limit
  7. GRB 230606A: Fermi GBM Observation
  8. GRB 230606A: BOOTES-5/JGT optical upper limit
  9. LIGO/Virgo/KAGRA S230602ap: Zwicky Transient Facility observations
  10. GRB 230606A: Swift-XRT refined Analysis
  11. GRB 230604A: GRBAlpha detection
  12. GRB 230606A: Swift/UVOT Upper Limits
  13. LIGO/Virgo S230606z: Global MASTER-Net observations report
  14. GRB 230606A: Enhanced Swift-XRT position
  15. LIGO/Virgo S230606d: Global MASTER-Net observations report
  16. GRB 230606A: Swift detection of a burst
  17. Fermi-LAT gamma-ray observations of IceCube-230603A
  18. GRB 230604A: AstroSat CZTI detection of a short GRB
  19. LIGO/Virgo S230605o: Global MASTER-Net observations report
  20. LIGO/Virgo S230604z: Global MASTER-Net observations report
  21. IceCube-230603A - IceCube observation of a high-energy neutrino candidate track-like event
  22. GRB 230603A: Fermi GBM Final Real-time Localization
  23. LIGO/Virgo S230603aa: Global MASTER-Net observations report
  24. LIGO/Virgo S230602ap: Global MASTER-Net observations report
  25. GRB 230521A: VZLUSAT-2 detection
  26. GRB 230522A: GRBAlpha and VZLUSAT-2 joint detection
  27. LIGO/Virgo S230601bf: Global MASTER-Net observations report
  28. LIGO/Virgo S230531f: Global MASTER-Net observations report
  29. GRB 230525A: CALET Gamma-Ray Burst Monitor detection
  30. LIGO/Virgo/KAGRA S230529ay: Zwicky Transient Facility observations
  31. LIGO/Virgo/KAGRA S230528a: Zwicky Transient Facility observations
  32. LIGO/Virgo/KAGRA S230527ch: Zwicky Transient Facility observations
  33. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  34. LIGO/Virgo/KAGRA S230529ay: Upper limits from Fermi-GBM Observations
  35. LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  36. LIGO/Virgo S230529p: Global MASTER-Net observations report
  37. GRB 230529A: Fermi GBM Final Real-time Localization
  38. LIGO/Virgo S230525a: Global MASTER-Net observations report
  39. Fermi-LAT gamma-ray observations of IceCube-230524A
  40. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  41. GRB 230510A: Swift-BAT refined analysis
  42. GRB 230525A: Fermi GBM Detection
  43. GRB 230525A: Fermi GBM Final Localization
  44. GRB 230523B: GRBAlpha detection
  45. GRB 230524A: Fermi GBM Observation
  46. IceCube Alert 230524.47: Global MASTER-Net observations report
  47. IceCube-230524A - IceCube observation of a high-energy neutrino candidate track-like event
  48. GRB 230524B: AstroSat CZTI detection
  49. GRB 230524A: AstroSat CZTI detection
  50. GRB 230524A: AGILE detection
  51. Fermi trigger No 706610076: Global MASTER-Net observations report
  52. LIGO/Virgo S230524b: Global MASTER-Net observations report
  53. GRB 230524A: Fermi GBM Final Real-time Localization
  54. Fermi trigger No 706599831: Global MASTER-Net observations report
  55. Fermi trigger No 706536788: Global MASTER-Net observations report
  56. GRB 230523B: Name correction from GCN Circular 33859
  57. GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
  58. LIGO/Virgo/KAGRA S230521k: Additional candidates from Zwicky Transient Facility
  59. Fermi Gamma-ray Burst Monitor trigger 706536788/230523509 is not a GRB
  60. GRB 230523A: Fermi GBM Final Real-time Localization
  61. LIGO/Virgo S230522n: Global MASTER-Net observations report
  62. LIGO/Virgo S230522a: Global MASTER-Net observations report
  63. LIGO/Virgo/KAGRA S230522a: 2 counterpart neutrino candidates from IceCube neutrino searches
  64. LIGO/Virgo S230521k: Global MASTER-Net observations report
  65. LIGO/Virgo/KAGRA S230521k: Zwicky Transient Facility observations
  66. GRB 230518B: VZLUSAT-2 detection
  67. Fermi Gamma-ray Burst Monitor trigger 706338208/230521211 is not a GRB
  68. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  69. Fermi trigger No 706328428: Global MASTER-Net observations report
  70. IPN triangulation of GRB 230518A (short)
  71. Fermi trigger No 706331483: Global MASTER-Net observations report
  72. Fermi trigger No 706317104: Global MASTER-Net observations report
  73. GRB 230520A: CALET Gamma-Ray Burst Monitor detection
  74. GRB 230521A: Fermi GBM Final Real-time Localization
  75. GRB 230520B is not a GRB
  76. GRB 230520B: Fermi GBM Final Real-time Localization
  77. GRB 230520A: MAXI/GSC detection
  78. GRB 230518A: Fermi GBM Observation
  79. LIGO/Virgo/KAGRA S230518h: Upper limits from Konus-Wind observations
  80. GRB 230518A: Swift/BAT-GUANO detection
  81. GRB 230518A: Fermi GBM Final Real-time Localization
  82. Fermi Gamma-ray Burst Monitor trigger 706068974/230518095 is not a GRB
  83. LIGO/Virgo/Kagra S230518h: NED Galaxies in the Localization Volume
  84. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  85. LIGO/Virgo S230518h: Global MASTER-Net observations report
  86. LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  87. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  88. GRB 230510B: GRBAlpha detection
  89. Fermi trigger No 706014351: Global MASTER-Net observations report
  90. GRB 230517A: BALROG localization (Fermi Trigger 706014351 / GRB 230517462)
  91. Improved IPN triangulation of GRB 230512A
  92. GRB 230517A: Fermi GBM Final Real-time Localization
  93. GRB 230510B: Fermi GBM detection
  94. Fermi trigger No 705952199: Global MASTER-Net observations report
  95. GRB 230516A: Fermi GBM Final Real-time Localization
  96. IPN triangulation of GRB 230511D (short)
  97. IPN triangulation of GRB 230512A
  98. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  99. GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate
  100. GRB 230512A: Zwicky Transient Facility non-detection of GRB afterglow candidate

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