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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"

11609 results found.

  1. GRB 231020A: AstroSat CZTI detection
  2. GRB 231020B: AstroSat CZTI detection
  3. GRB 231024A: GOTO optical counterpart candidate
  4. GRB 231024A: Fermi GBM Final Localization
  5. Fermi trigger No 719846439: Global MASTER-Net observations report
  6. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  7. GRB 231020A: Fermi GBM Detection
  8. GRID detection of GRB 231004A
  9. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  10. GRB 231019A: VZLUSAT-2 detection
  11. GRB 231018A: VZLUSAT-2 detection
  12. GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
  13. GRB 231020B: Fermi GBM Final Real-time Localization
  14. GRB 231020A: BALROG localization (Fermi Trigger / GRB 231020790)
  15. LIGO/Virgo/KAGRA S231020ba: Upper limits from Fermi-GBM Observations
  16. Fermi GRB 231020A: Global MASTER-Net observations report
  17. GRB 231020A: Fermi GBM Final Real-time Localization
  18. GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  19. GRB 231017A: 1.3m DFOT Optical upper limit
  20. IceCube-231004A: Upper limits from Fermi-GBM Observations
  21. GRB 231018A: GRBAlpha detection
  22. GRB 231018A: CALET Gamma-Ray Burst Monitor detection
  23. Fermi GRB 231019A: Global MASTER-Net observations report
  24. GRB 231018A: Glowbug gamma-ray detection
  25. Konus-Wind detection of GRB 231018A
  26. IPN triangulation of GRB 231018A
  27. GRB 231017A: Swift/UVOT Upper Limit
  28. GRB 231019A: Fermi GBM Final Real-time Localization
  29. GRB 231017A: GOTO optical upper limits
  30. GRB 231017A: JinShan optical upper limit
  31. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  32. GRB 231017A: Las Cumbres optical upper limit
  33. GRB 231017A: LCOGT Optical Upper Limits
  34. GRB231017A: GROWTH-India upper limits on the optical afterglow
  35. GRB 231018A: Fermi GBM Detection
  36. GRB 231017A: Fermi GBM Detection
  37. GRB 231012B may not be a GRB
  38. GRB 231018A: BALROG localization (Fermi Trigger / GRB 231018521)
  39. GRB 231018A: Fermi GBM Final Real-time Localization
  40. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  41. Fermi-LAT gamma-ray observations of IceCube-231014A
  42. GRB231017A: Fermi GBM Final Localization
  43. IceCube-231014A - IceCube observation of a high-energy neutrino candidate track-like event
  44. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  45. GRB 231012A: Fermi GBM Final Real-time Localization
  46. GRB 231012A: Fermi GBM Final Real-time Localization
  47. GRB 231004A: Glowbug gamma-ray detection
  48. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  49. Fermi-LAT gamma-ray observations of IceCube-231004A
  50. IceCube-231004A - IceCube observation of a high-energy neutrino candidate track-like event
  51. GRB 231004A: Fermi GBM Final Real-time Localization
  52. GRB 231003A is not a GRB
  53. GRB 231003A: Fermi GBM Final Real-time Localization
  54. GRB 230827B: 10.4m GTC spectroscopic redshift
  55. GRB 230930A: Fermi GBM Final Real-time Localization
  56. AT2023sva / GRB230916B: GIT observations of the afterglow
  57. transient AT2023sva: A Binary Driven Hypernova with a possible associated supernova
  58. Konus-Wind detection of GRB 230919A
  59. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  60. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  61. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  62. GRB 230921A: Fermi GBM Final Real-time Localization
  63. GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova
  64. IPN triangulation of GRB 230919A (short)
  65. GRB 230919A: Fermi GBM Observation
  66. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  67. Fermi GBM Statement for Trigger 716527670/230916144
  68. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  69. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  70. GRB 230919A: AstroSat CZTI detection
  71. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  72. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  73. GRB 230919A: Fermi GBM Final Real-time Localization
  74. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  75. GRB 230918B: Fermi GBM Final Real-time Localization
  76. GRB 230918A (short): Glowbug gamma-ray detection
  77. GRB 230916B: Glowbug gamma-ray detection
  78. AT 2023sva: NOT observations of the ZTF candidate afterglow
  79. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  80. GRB 230915A: Fermi GBM observation
  81. GRB 230812B: Radio observations with the uGMRT
  82. GRB 230918A: Fermi GBM Final Real-time Localization
  83. GRB 230911A: Fermi GBM Observation
  84. Fermi trigger No 716572242: Global MASTER-Net observations report
  85. Fermi trigger No 716544961: Global MASTER-Net observations report
  86. Fermi-LAT gamma-ray observations of IceCube-230914A
  87. GRB 230915A: Swift/BAT-GUANO detection of a burst
  88. GRB 230911D: GRBAlpha detection
  89. GRB 230906A: optical counterpart
  90. GRB 230911A: Swift-XRT afterglow detection
  91. Fermi trigger No 716449174: Global MASTER-Net observations report
  92. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  93. Fermi trigger No 716419312: Global MASTER-Net observations report
  94. GRB 230913A: Glowbug gamma-ray detection
  95. GRB 230812B: Bad Time Intervals for Fermi GBM data
  96. IceCube-230914A - IceCube observation of a high-energy neutrino candidate track-like event
  97. GRB 230913A: Fermi GBM Observation
  98. GRB 230911A: Swift ToO observations
  99. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  100. Fermi GRB 230913A: Global MASTER-Net observations report

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