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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"

27302 results found.

  1. GRB 230524A: Fermi GBM Final Real-time Localization
  2. Fermi trigger No 706599831: Global MASTER-Net observations report
  3. Fermi trigger No 706536788: Global MASTER-Net observations report
  4. GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
  5. LIGO/Virgo/KAGRA S230521k: Additional candidates from Zwicky Transient Facility
  6. Fermi Gamma-ray Burst Monitor trigger 706536788/230523509 is not a GRB
  7. GRB 230523A: Fermi GBM Final Real-time Localization
  8. LIGO/Virgo S230522n: Global MASTER-Net observations report
  9. LIGO/Virgo S230522a: Global MASTER-Net observations report
  10. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
  11. LIGO/Virgo/KAGRA S230522a: 2 counterpart neutrino candidates from IceCube neutrino searches
  12. LIGO/Virgo S230521k: Global MASTER-Net observations report
  13. LIGO/Virgo/KAGRA S230521k: Zwicky Transient Facility observations
  14. GRB 230518B: VZLUSAT-2 detection
  15. Fermi Gamma-ray Burst Monitor trigger 706338208/230521211 is not a GRB
  16. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  17. Fermi trigger No 706328428: Global MASTER-Net observations report
  18. IPN triangulation of GRB 230518A (short)
  19. Fermi trigger No 706331483: Global MASTER-Net observations report
  20. Fermi trigger No 706317104: Global MASTER-Net observations report
  21. GRB 230520A: CALET Gamma-Ray Burst Monitor detection
  22. GRB 230521A: Fermi GBM Final Real-time Localization
  23. GRB 230520B is not a GRB
  24. GRB 230520B: Fermi GBM Final Real-time Localization
  25. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
  26. GRB 230518A: Fermi GBM Observation
  27. GRB 230518A: Swift/BAT-GUANO detection
  28. LIGO/Virgo S230518h: Swift XRT observations, 8 X-ray sources
  29. LIGO/Virgo/KAGRA S230518h: Coverage and upper limits from MAXI/GSC observations
  30. GRB 230518A: Fermi GBM Final Real-time Localization
  31. Fermi Gamma-ray Burst Monitor trigger 706068974/230518095 is not a GRB
  32. LIGO/Virgo/KAGRA S230518h: AstroSat CZTI non-detection and upper limits
  33. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  34. LIGO/Virgo S230518h: Global MASTER-Net observations report
  35. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  36. Fermi trigger No 706014351: Global MASTER-Net observations report
  37. GRB 230517A: BALROG localization (Fermi Trigger 706014351 / GRB 230517462)
  38. GRB 230517A: Fermi GBM Final Real-time Localization
  39. GRB 230510B: Fermi GBM detection
  40. Fermi trigger No 705952199: Global MASTER-Net observations report
  41. GRB 230516A: Fermi GBM Final Real-time Localization
  42. IPN triangulation of GRB 230511D (short)
  43. IPN triangulation of GRB 230512A
  44. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  45. GRB 230512A: GIT non detection of afterglow candidate
  46. GRB 230513A: Fermi GBM Final Real-time Localization
  47. Fermi trigger No 705565670: Global MASTER-Net observations report
  48. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  49. GRB 230512A: GIT optical follow-up ZTF candidates
  50. GRB 230512A: Fermi GBM detection
  51. GRB 230512A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705565670)
  52. GRB 230430A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 704533643)
  53. GRB 230511D: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705537623)
  54. GRB 230512A: Fermi-LAT detection
  55. GRB 230512A: Fermi GBM Final Localization
  56. GRB 230510A: GIT optical upper limits
  57. GRB 230510A: LCOGT Optical Upper Limit
  58. GRB 230511D: Fermi GBM Final Real-time Localization
  59. GRB 230510A: Swift/UVOT Observations
  60. GRB 230511C: Fermi GBM Final Localization
  61. Fermi trigger No 705503315: Global MASTER-Net observations report
  62. GRB 230511B: Fermi GBM Final Real-time Localization
  63. Fermi trigger No 705496510: Global MASTER-Net observations report
  64. GRB 230511A: Fermi GBM Final Real-time Localization
  65. GRB 230510A: Fermi GBM detection
  66. Fermi trigger No 705446499: Global MASTER-Net observations report
  67. GRB 230510A: Gaoyazi/GOT optical upper limit
  68. GRB 230510B: CALET Gamma-Ray Burst Monitor detection
  69. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  70. GRB 230510A: Nanshan/NEXT optical afterglow detection
  71. GRB 230510B: MAXI/GSC detection
  72. GRB 230510B: Fermi GBM Final Real-time Localization
  73. GRB 230506B: Fermi GBM detection
  74. GRB 230510A: Swift-XRT refined Analysis
  75. GRB 230506C: Fermi GBM detection
  76. Fermi trigger No 705413051: Global MASTER-Net observations report
  77. Fermi Gamma-ray Burst Monitor trigger 230510133/705381054 is not a GRB
  78. GRB 230510A: Swift detection of a burst
  79. GRB 230510A: Fermi GBM Final Real-time Localization
  80. GRB 230506C: SAO RAS optical observations
  81. GRB 230506C: Swift-XRT refined Analysis
  82. GRB 230506C: Swift-BAT refined analysis
  83. GRB 230506B: Swift-BAT refined analysis
  84. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  85. GRB 230506B: LCOGT Optical Upper Limits
  86. GRB 230506C: Swift/UVOT Upper Limits
  87. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  88. GRB 230506B: Swift-XRT refined Analysis
  89. GRB 230506C: Swift-XRT analysis
  90. GRB 230506C: Candidate afterglow observation by D50
  91. GRB 230506B: Swift/UVOT Detection
  92. GRB 230506C: Swift detection of a burst
  93. Swift GRB230506.71: Global MASTER-Net observations report
  94. GRB 230506B: Swift detection of a burst
  95. GRB 230506B: MASTER optical observations
  96. GRB 230506B: Swift detection of a burst
  97. GRB 230506A: Fermi GBM Final Real-time Localization
  98. Fermi trigger No 704837952: Global MASTER-Net observations report
  99. GRB 230427A: Swift-BAT refined analysis
  100. GRB 230503A: Fermi GBM Final Real-time Localization

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