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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

11527 results found.

  1. GRB 200317A: AstroSat CZTI detection
  2. Fermi trigger No 606681997: Global MASTER-Net observations report
  3. GRB 200323A: Fermi GBM detection
  4. GRB 200323A: Fermi GBM Final Real-time Localization
  5. Fermi trigger No 606614927: Global MASTER-Net observations report
  6. GRB 200320A: Fermi GBM Final Localization
  7. GRB 200319A: BALROG localization (Fermi Trigger 606296685 / GRB 200319323)
  8. GRB 200319A: Fermi GBM Final Real-time Localization
  9. Fermi trigger No 606263732: Global MASTER-Net observations report
  10. GRB 200318A: Fermi GBM Final Real-time Localization
  11. Konus-Wind observation of GRB 200313B
  12. LIGO/Virgo S200316bj: No counterpart candidates in Fermi-LAT observations
  13. Konus-Wind observation of GRB 200313A
  14. Konus-Wind observation of GRB 200311A
  15. LIGO/Virgo S200316bj: Upper limits from Fermi-GBM Observations
  16. Fermi trigger No 606098435: Global MASTER-Net observations report
  17. GRB 200317A: Fermi GBM Final Real-time Localization
  18. IPN triangulation of GRB 200313B (short)
  19. IPN triangulation of GRB 200313A
  20. GRB 200313A: Fermi GBM detection
  21. IPN triangulation of GRB 200311A
  22. Fermi trigger No 605789837: Global MASTER-Net observations report
  23. GRB 200313B: Fermi GBM Final Real-time Localization
  24. GRB 200313A: BALROG localization (Fermi Trigger 605756501 / GRB 200313071)
  25. Fermi trigger No 605756501: Global MASTER-Net observations report
  26. GRB 200313A: Fermi GBM Final Real-time Localization
  27. GRB 200311A: AstroSat CZTI detection
  28. Fermi trigger No 605632577: Global MASTER-Net observations report
  29. LIGO/Virgo S200311bg: No significant counterpart candidates in Fermi-LAT observations
  30. IPN triangulation of GRB 200307A (short)
  31. GRB 200311A: AGILE/MCAL and scientific ratemeters observations
  32. LIGO/Virgo S200311bg: not observable by Fermi GBM
  33. GRB 200311A: Fermi GBM Final Real-time Localization
  34. GRB 200307A: Updated localization from Fermi/GBM and Swift/BAT-GUANO
  35. GRB 200308A: Fermi GBM Final Real-time Localization
  36. Fermi trigger No 605309224: Global MASTER-Net observations report
  37. GRB 200307A: Fermi GBM Final Real-time Localization
  38. GRB 200306B: Fermi GBM Final Localization Correction
  39. GRB 200306B: Fermi GBM Final Real-time Localization
  40. GRB 200228B: continued optical observations
  41. Konus-Wind observation of GRB200303A
  42. GRB 200303A: Fermi GBM observation
  43. GRB 200303A: NOT optical observations
  44. GRB 200303A: FRAM-ORM optical limit
  45. GRB 200219A: AstroSat CZTI detection
  46. GRB 200303A: GOTO observations upper limit
  47. GRB 200228A: AstroSat CZTI detection
  48. GRB 200303A: CALET Gamma-Ray Burst Monitor detection
  49. GRB 200219C: VLA Detection
  50. Fermi trigger No 604895668: Global MASTER-Net observations report
  51. GRB 200303A: Fermi GBM Final Real-time Localization
  52. LIGO/Virgo S200302c: No significant counterpart candidates in Fermi-LAT observations
  53. LIGO/Virgo S200302c: Upper limits from Fermi-GBM Observations
  54. GRB 200228B: Mondy, TSHAO, AbAO and CrAO optical observations, afterglow candidate
  55. GRB 200228B: RATIR Optical Observations
  56. GRB 200228B: Liverpool Telescope imaging
  57. GRB 200228B: Fermi GBM observation
  58. GRB 200228A: Fermi GBM observation
  59. GRB 200228A: Swift/BAT detection and arcminute localization from GUANO
  60. GRB 200227A: Mondy optical upper limit
  61. Fermi-LAT Gamma-ray Observations of IceCube-200227A
  62. GRB 200228B: Fermi GBM Final Real-time Localization
  63. Fermi trigger No 604565918: Global MASTER-Net observations report
  64. GRB 200227A: Insight-HXMT/HE detection
  65. GRB 200228A: BALROG localization (Fermi Trigger 604565918 / GRB 200228291)
  66. GRB 200228A: Fermi GBM Final Real-time Localization
  67. GRB 200219A: ATCA 5/9 GHz radio observations
  68. IceCube-200227A: Upper limits from Fermi-GBM Observations
  69. GRB 200224A: Mondy optical upper limit
  70. GRB 200227A: Fermi GBM observation
  71. GRB 200227A: MITSuME Akeno optical upper limit
  72. GRB 200227A: Fermi GBM Final Real-time Localization
  73. Konus-Wind observation of GRB 200219C
  74. Konus-Wind observation of GRB 200219A
  75. GRB 200224B: DDOTI/OAN optical observations report
  76. IPN triangulation of GRB 200221A (short)
  77. LIGO/Virgo S200225q: Upper limits from Fermi-GBM Observations
  78. Fermi trigger No 604231129: Global MASTER-Net observations report
  79. LIGO/Virgo S200225q: No counterpart candidates in Fermi-LAT observations
  80. LIGO/Virgo S200224ca: No counterpart candidates in Fermi-LAT observations
  81. LIGO/Virgo S200224ca: not observable by Fermi-GBM
  82. IPN triangulation of GRB 200224C
  83. Correction in name: GRB 200224B and GRB 200224C (not GRB 200224A)
  84. GRB 200219C: Swift-XRT afterglow confirmation
  85. GRB 200224C: Fermi GBM Final Real-time Localization
  86. Fermi trigger No 604213554: Global MASTER-Net observations report
  87. GRB 200224B: Fermi GBM Final Real-time Localization
  88. GRB 200223A: Fermi GBM Final Real-time Localization
  89. IPN triangulation of GRB 200219B (inconsistent with the LIGO/Virgo S200219ac)
  90. GRB 200219C: OAJ afterglow confirmation
  91. GRB 200219C: CALET Gamma-Ray Burst Monitor detection
  92. GRB 200219C: Mondy and TSHAO optical observations
  93. GRB 200219C: Nanshan/NEXT optical upper limit and possible host galaxy from PanSTARRS
  94. GRB 200221A: Fermi GBM Final Real-time Localization
  95. Fermi trigger No 603949983: Global MASTER-Net observations report
  96. GRB 200219C: Swift-XRT afterglow detection
  97. GRB 200219C: DDOTI Observations
  98. GRB 200219C: Fermi GBM detection
  99. GRB 200219C: Tiled Swift observations
  100. GRB 200219C: Fermi-LAT detection

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