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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 230707B: CALET Gamma-Ray Burst Monitor detection
  2. GRB 230703A detected with multiple GRID detectors
  3. GRB 230709C: BALROG localization (Fermi Trigger 710617111 / GRB 230709735)
  4. GRB 230709B: BALROG localization (Fermi Trigger 710614579 / GRB 230709706)
  5. Swift Trigger 1178410: possible GRB 230709A
  6. LIGO/Virgo/KAGRA S230708bi: Retraction of GW compact binary merger candidate
  7. GRB 230628C: GRID Detection
  8. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  9. IceCube Alert 230708.35: Global MASTER-Net observations report
  10. GRB 230707B: Fermi GBM Final Real-time Localization
  11. IceCube Alert 230707.71: Global MASTER-Net observations report
  12. GRB 230707A: Fermi GBM Detection
  13. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  14. Fermi GRB 230707A: Global MASTER-Net observations report
  15. GRB 230707A: Fermi GBM Final Real-time Localization
  16. Integral GRB230706.70: Global MASTER-Net observations report
  17. IBAS trigger number 10311: not a real GRB
  18. GRB 230625A: Detection by GRID
  19. Fermi trigger No 710117592: Global MASTER-Net observations report
  20. GRB 230626A: VZLUSAT-2 detection
  21. GRB 230328B: LBT detection of the likely host galaxy
  22. GRB 230628E: Swift/UVOT Detection
  23. GRB 230628E: Swift-BAT refined analysis
  24. GRB 230702A: Fermi GBM Final Real-time Localization
  25. GRB 230701A: Fermi GBM Final Real-time Localization
  26. LIGO/Virgo/KAGRA S230627c: GRANDMA observations of galaxies and ZTF counterpart candidates
  27. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230701z: one counterpart neutrino candidate from IceCube neutrino searches
  28. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  29. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  30. Fermi GRB 230628C: Global MASTER-Net observations report
  31. GRB 230628E: Swift-XRT refined Analysis
  32. Fermi GRB 230628D: Global MASTER-Net observations report
  33. GRB 230628E: LCOGT Optical Upper Limit
  34. Swift GRB230628.93: Global MASTER-Net observations report
  35. GRB 230628E: Swift detection of a burst
  36. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  37. GRB 230628D: Fermi GBM Final Real-time Localization
  38. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230628aj: one counterpart neutrino candidate from IceCube neutrino searches
  39. GRB 230628C: Fermi GBM Final Real-time Localization
  40. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  41. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  42. LIGO/Virgo/KAGRA S230516az: GOTO candidate counterpart GOTO23hu ruled out by Zwicky Transient Facility observations
  43. GRB 230628A: Fermi GBM Final Localization
  44. LIGO/Virgo/KAGRA S230627c: Additional observations from the Zwicky Transient Facility
  45. GRB 230626A: GRBAlpha detection
  46. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  47. LIGO/Virgo/KAGRA S230627c: ATLAS information on the ZTF candidates
  48. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  49. GRB230626A: Fermi GBM Detection
  50. LIGO/Virgo/KAGRA S230627c: Global MASTER-Net observations report
  51. LIGO/Virgo/KAGRA S230627c: Correction to HasMassGap probability
  52. LIGO/Virgo/KAGRA S230627c: Zwicky Transient Facility observations and candidates
  53. LIGO/Virgo/KAGRA S230627c: Coverage and upper limits from MAXI/GSC observations
  54. GRB 230618A: Swift-BAT refined analysis
  55. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  56. GRB 230622A: Swift-BAT refined analysis
  57. GRB 230625A: Fermi GBM Final Real-time Localization
  58. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  59. MAXI GRB 230623A: MASTER optical observations
  60. GRB 230622A: Swift-XRT refined Analysis
  61. Swift GRB 230622A: Global MASTER-Net observations report
  62. LIGO/Virgo/KAGRA S230615az: LBT spectroscopic classification of GOTO23hn
  63. LIGO/Virgo/KAGRA S230622ba: Retraction of GW compact binary merger candidate
  64. LIGO/Virgo S230622e: Global MASTER-Net observations report
  65. LIGO/Virgo S230621bq: Global MASTER-Net observations report
  66. LIGO/Virgo S230621ad: Global MASTER-Net observations report
  67. LIGO/Virgo/KAGRA S230615az: LBT spectroscopic redshift of the host galaxy of GOTO23hn
  68. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  69. GRB 230622A: Swift detection of a burst
  70. GRB 230621A: Fermi GBM Final Localization Correction
  71. Fermi trigger No 709083929: Global MASTER-Net observations report
  72. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  73. LIGO/Virgo S230620ad: Global MASTER-Net observations report
  74. LIGO/Virgo S230620au: Global MASTER-Net observations report
  75. LIGO/Virgo/KAGRA S230619bg: one counterpart neutrino candidate from IceCube neutrino searches
  76. LIGO/Virgo S230620al: Global MASTER-Net observations report
  77. LIGO/Virgo S230620af: Global MASTER-Net observations report
  78. LIGO/Virgo S230620z: Global MASTER-Net observations report
  79. LIGO/Virgo S230620w: Global MASTER-Net observations report
  80. LIGO/Virgo S230619bg: Global MASTER-Net observations report
  81. LIGO/Virgo S230620g: Global MASTER-Net observations report
  82. LIGO/Virgo S230619ay: Global MASTER-Net observations report
  83. LIGO/Virgo S230619bd: Global MASTER-Net observations report
  84. LIGO/Virgo S230619bb: Global MASTER-Net observations report
  85. LIGO/Virgo S230619as: Global MASTER-Net observations report
  86. LIGO/Virgo S230619ap: Global MASTER-Net observations report
  87. LIGO/Virgo S230619i: Global MASTER-Net observations report
  88. LIGO/Virgo S230619aa: Global MASTER-Net observations report
  89. LIGO/Virgo S230619x: Global MASTER-Net observations report
  90. LIGO/Virgo S230619e: Global MASTER-Net observations report
  91. LIGO/Virgo S230618at: Global MASTER-Net observations report
  92. LIGO/Virgo S230618ba: Global MASTER-Net observations report
  93. LIGO/Virgo S230618az: Global MASTER-Net observations report
  94. LIGO/Virgo S230618ae: Global MASTER-Net observations report
  95. LIGO/Virgo S230618aq: Global MASTER-Net observations report
  96. LIGO/Virgo S230618y: Global MASTER-Net observations report
  97. LIGO/Virgo S230618s: Global MASTER-Net observations report
  98. GRB 230618A: Swift/UVOT Upper Limits
  99. GRB 230618A: Swift-XRT refined Analysis
  100. LIGO/Virgo S230618r: Global MASTER-Net observations report

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