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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 190805B: MAXI/GSC detection
  2. GRB 190805B: Fermi GBM Final Real-time Localization
  3. GRB 190805A: Fermi GBM Final Real-time Localization
  4. Fermi trigger No 586638042 Global MASTER-Net observations report
  5. MAXI GRB190804.33 Global MASTER-Net observations report
  6. Fermi trigger No 586600841 Global MASTER-Net observations report
  7. GRB 190804C: BALROG localization (Fermi Trigger 586638042 / GRB 190804792)
  8. GRB 190804C: Fermi GBM Final Real-time Localization
  9. Fermi trigger No 586574612 Global MASTER-Net observations report
  10. GRB 190804A: Fermi GBM Final Real-time Localization
  11. GRB 190731A: AstroSat CZTI detection
  12. GRB 190731A: Swift/UVOT Upper Limits
  13. GRB 190731A: no OT detected by MASTER
  14. IceCube 190730A: No counterpart candidates or blazar activity in GOTO observations
  15. IPN Triangulation of GRB 190731A
  16. GRB 190731A: Fermi GBM detection
  17. GRB 190731A: CALET Gamma-Ray Burst Monitor detection
  18. GRB190731A: Fermi-LAT detection
  19. Fermi trigger No 586305505 Global MASTER-Net observations report
  20. Fermi trigger No 586305505 Global MASTER-Net observations report
  21. GRB 190731A: Fermi GBM Final Real-time Localization
  22. LIGO/Virgo S190728q: No counterpart candidates in H.E.S.S. observations
  23. LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215
  24. Fermi trigger No 586240252 Global MASTER-Net observations report
  25. IceCube-190730A: MASTER optical observation
  26. LIGO/Virgo S190707q: AstroSat CZTI upper limits
  27. LIGO/Virgo S190718y: AstroSat CZTI upper limits
  28. LIGO/Virgo S190727h: AstroSat CZTI upper limits
  29. LIGO/Virgo S190720a: AstroSat CZTI upper limits
  30. Fermi Gamma-ray Burst Monitor trigger 190729668/586108936 is not a GRB
  31. LIGO/Virgo S190728q: Optical Counterpart Candidates from DECam-GROWTH
  32. LIGO/Virgo S190728q: No transient candidates in CALET observations
  33. LIGO/Virgo S190728q: No counterpart candidates in KAIT observations
  34. GRB 190727B: Swift-BAT refined analysis
  35. LIGO/Virgo S190728q: Third update on neutrino search with IceCube
  36. IPN triangulation of GRB 190728A (short)
  37. LIGO/Virgo S190728q: Identification of a Faint Blue Static Source at the Location of ZTF19abjethn
  38. LIGO/Virgo S190728q: Photometric Redshift and Stellar Mass Estimates for the Potential Host Galaxy of Optical Counterpart Candidate ZTF19abjethn
  39. LIGO/Virgo S190728q: No counterpart candidates in the Swift/BAT Observations
  40. LIGO/Virgo S190728q: Optical Candidate from the Zwicky Transient Facility ZTF19abjethn
  41. LIGO/Virgo S190728q: No counterpart candidates in Fermi-LAT observations
  42. LIGO/Virgo S190728q: Second update on neutrino search with IceCube
  43. LIGO/Virgo S190728q: Upper limits from Fermi-GBM Observations
  44. LIGO/Virgo S190728q: One neutrino candidate from IceCube search
  45. LIGO/Virgo S190728q: No counterpart candidates in HAWC observations
  46. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  47. GRB 190727B: Fermi-LAT detection
  48. LIGO/Virgo S190727h: No transient candidates in CALET observations
  49. LIGO/Virgo S190728q Global MASTER-Net observations report
  50. Fermi trigger No 585988241 Global MASTER-Net observations report
  51. GRB 190728A: Fermi GBM Final Real-time Localization
  52. GRB 190727B: Fermi GBM observations
  53. LIGO/Virgo S190727h: No counterpart candidates in KAIT observations
  54. GRB 190727B: BALROG localization (Fermi Trigger 585951481 / GRB 190727846)
  55. GRB 190727B: Fermi GBM Final Real-time Localization
  56. GRB 190727B: Swift detection of a burst
  57. GRB 190727A: BALROG localization (Fermi Trigger 585936117 / GRB 190727668)
  58. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  59. GRB 190727A: Fermi GBM Final Real-time Localization
  60. LIGO/Virgo S190727h: No counterpart candidates in Fermi-LAT observations
  61. LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
  62. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  63. LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
  64. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  65. LIGO/Virgo S190727h Global MASTER-Net observations report
  66. Fermi trigger No 585864875 Global MASTER-Net observations report
  67. Fermi trigger No 585847498 Global MASTER-Net observations report
  68. GRB 190726B: BALROG localization (Fermi Trigger 585864875 / GRB 190726843)
  69. GRB 190726B: Fermi GBM Final Real-time Localization
  70. Fermi trigger No 585856427 Global MASTER-Net observations report
  71. GRB 190726A: BALROG localization (Fermi Trigger 585847498 / GRB 190726642)
  72. GRB 190726A: Fermi GBM Final Real-time Localization
  73. LIGO/Virgo S190718y: Swift XRT observations, 45 X-ray sources
  74. GRB 190724A: Insight-HXMT/HE detection
  75. GRB 190723A: Insight-HXMT/HE detection
  76. GRB 190720A: CALET Gamma-Ray Burst Monitor detection
  77. IPN triangulation of GRB 190724A (short)
  78. Fermi trigger No 585621841 Global MASTER-Net observations report
  79. GRB 190724A: Fermi GBM Final Real-time Localization
  80. Fermi trigger No 585559462 Global MASTER-Net observations report
  81. GRB 190723A: Fermi GBM Final Real-time Localization
  82. IPN triangulation of GRB 190720A
  83. GRB 190720B: Insight-HXMT/HE detection
  84. LIGO/Virgo S190720a: No counterpart candidates in Fermi-LAT observations
  85. LIGO/Virgo S190720a: Upper limits from CALET observations
  86. LIGO/Virgo S190720a: No counterpart candidates in KAIT observations
  87. GRB 190720B: Fermi GBM Final Real-time Localization
  88. GRB 190720A: Fermi GBM detection
  89. GRB 190719C: Fermi GBM detection
  90. GRB 190719C: Swift-BAT refined analysis
  91. GRB 190719C: Swift/UVOT Upper Limits
  92. LIGO/Virgo S190720a: No counterpart candidates in the Swift/BAT Observations
  93. GRB 190719C: Swift-XRT refined Analysis
  94. GRB 190720A: BALROG localization (Fermi Trigger 585326534 / GRB 190720613)
  95. GRB 190720A: Fermi GBM Final Real-time Localization
  96. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  97. LIGO/Virgo S190720a: Coverage and upper limits from MAXI/GSC observations
  98. LIGO/Virgo S190720a: AGILE-MCAL observations
  99. LIGO/Virgo S190720a Global MASTER-Net observations report
  100. LIGO/Virgo S190720a: No counterpart candidates in HAWC observations

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