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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"

5186 results found.

  1. LIGO/Virgo G275697: Additional iPTF Optical Transient Candidates
  2. LIGO/Virgo G275404: Additional iPTF Optical Transient Candidates
  3. LIGO/Virgo G275697: Fermi GBM Upper Limits
  4. LIGO/Virgo G275697: optical spectroscopy of Swift/XRT source 1
  5. LIGO/Virgo G275404: Fermi GBM Upper Limits
  6. LIGO/Virgo G275404: Nearby galaxy observations by J-GEM collaboration
  7. LIGO/Virgo G275697: Swift-XRT sources
  8. LIGO/Virgo G274296: Liverpool Telescope classification of EM candidates
  9. LIGO/Virgo G274296: PIRATE Observations
  10. LIGO/Virgo G274296: J-GEM optical/NIR follow-up observations
  11. Swift Trigger 739517 is probably not a GRB
  12. LIGO/Virgo G274296: Asiago 1.82m Optical Observations
  13. LIGO/Virgo G274296: PESSTO classification of 9 Pan-STARRS transients
  14. IPN Triangulation of GRB 170219A (short/hard)
  15. LIGO/Virgo G274296: Pan-STARRS imaging and discovery of 70 transients
  16. Trigger 738728: Swift triggered on noise near NGC 4096
  17. Fermi Trigger 508295323: MASTER-OAFA possible OT detection
  18. GRB 170208A: Swift-XRT refined Analysis
  19. Konus-Wind observation of GRB 170208A
  20. GRB 170208B: NOT upper limits
  21. GRB 170208B: Swift-XRT refined Analysis
  22. GRB 170206B: Swift-XRT refined Analysis
  23. GRB 170205A: Swift-XRT refined Analysis
  24. GRB 170202A: Swift-XRT refined Analysis
  25. GRB 170203A: Swift detection of a burst
  26. LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
  27. GRB 170127B: Swift-XRT refined Analysis
  28. GRB 170127A: Swift-XRT refined Analysis
  29. GRB 170124A: CALET Gamma-Ray Burst Monitor detection
  30. GRB 170127C: Fermi GBM detection
  31. GRB 170126A: Swift-XRT refined Analysis
  32. LIGO/Virgo G270580: Fermi GBM Observations
  33. LIGO/Virgo G270580: Swift-XRT follow-up of PS17yt
  34. LIGO/Virgo G270580: GMG photometric follow-up of PS17yt
  35. LIGO/Virgo G270580: 10.4m GTC spectroscopic observations of PS17yt
  36. LIGO/Virgo G270580: Liverpool Telescope classification of EM candidates
  37. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  38. LIGO/Virgo G270580: CALET Observations
  39. LIGO/Virgo G270580: A third optical transient from CNEOST
  40. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
  41. LIGO/Virgo G270580: AGILE MCAL and Super-AGILE Observations
  42. GRB 170115A : AbAO optical upper limit
  43. GRB 170115A: Swift-XRT refined Analysis
  44. GRB 170113A: Swift-XRT refined Analysis
  45. GRB 170112A: Swift detection of a short burst
  46. GRB 170111A: Swift-XRT refined Analysis
  47. Trigger 731535: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  48. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  49. Trigger 731257: Another Swift-BAT detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  50. Trigger 731183: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  51. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  52. LIGO/Virgo G268556: ATLAS imaging of the skymap
  53. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  54. GRS 1716-249/GRO J1719-24/V2293 Oph, Swift-BAT refined analysis
  55. GRB 161224A: Swift-XRT refined Analysis
  56. Fermi GBM trigger 504233075/161224301 is not a GRB
  57. GRB 161220A: Swift-XRT refined Analysis
  58. IPN Triangulation of GRB 161218B (long/very bright)
  59. GRB 161219B: Swift-XRT refined Analysis
  60. GRB 161217A: Swift-XRT refined Analysis
  61. Fermi-LAT Gamma-ray Observations of IceCube-161210
  62. MASTER: Optical Blazar Flare Detection during Fermi trigger 502272781 inspection
  63. GRB 161202A: Swift-XRT refined Analysis
  64. GRB 161129A: Swift-XRT refined Analysis
  65. GRB 161123A: MAXI/GSC detection
  66. GRB 161119A: MASTER-SAAO possible OT detection during Fermi Alert
  67. GRB 161117A: Swift-XRT refined Analysis
  68. GRB 161109A: Fermi GBM observation
  69. GRB 161108A: NOT candidate afterglow
  70. GRB 161105A: Swift-XRT refined Analysis
  71. GRB 161104A: Swift-XRT refined Analysis
  72. GRB 161023A: GROND Observations
  73. GRB 161023A: Swift-XRT afterglow detection
  74. GRB 161023A: LCOGT-FTS optical observations
  75. GRB 161023A (Integral trigger 7613) MASTER-Net bright OT detection
  76. Swift Trigger 718766 is not an astrophysical event.
  77. GRB 161022A: Swift-XRT refined Analysis
  78. GRB 161017A: Swift-XRT refined Analysis
  79. GRB 161011A: Swift-XRT refined Analysis
  80. GRB 161010A: Swift-XRT afterglow detection
  81. GRB 161007A: Swift-XRT refined Analysis
  82. GRB 160925A: Kottamia R-band observation
  83. GRB 161004B: Swift-XRT refined Analysis
  84. GRB 161004A: Swift-XRT refined Analysis
  85. GRB 161001A: Swift-XRT refined Analysis
  86. GRB 160927A: NOT optical observations
  87. GRB 160927A: Swift-XRT refined Analysis
  88. GRB 160927A: RTT150 optical afterglow candidate
  89. GRB 160925A: MITSuME Akeno Optical Observations
  90. GRB 160917A: Swift/UVOT Detection
  91. GRB 160917A: Swift-XRT refined Analysis
  92. GRB 160917A: Mondy optical observations
  93. GRB 160917A: Enhanced Swift-XRT position
  94. GRB 160917A: Swift detection of a burst
  95. GRB 160905A: Swift-XRT refined Analysis
  96. GRB 160824B: Lomonosov BDRG gamma ray detection and MASTER limit
  97. GRB 160824B: CALET Gamma-Ray Burst Monitor detection
  98. GRB 160826A: Swift-XRT refined Analysis
  99. GRB 160821A: CALET Gamma-Ray Burst Monitor detection
  100. GRB 160824A: ISON/Terskol optical observations

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