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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. Fermi GBM-190816: Eight additional candidates from the Zwicky Transient Facility
  2. GRB 190827A: BALROG localization (Fermi Trigger 588597173 / GRB 190827467)
  3. GRB 190827A: Fermi GBM Final Real-time Localization
  4. GRB 190824A, Swift-BAT refined analysis
  5. GRB 190824A: Swift/UVOT Upper Limits
  6. Fermi trigger No 588398821 Global MASTER-Net observations report
  7. LIGO/Virgo S190814bv: MASTER prediscovery and postdiscovery observations DECam candidate DG19wxnjc/AT2019npv field
  8. GRB 190825A: Fermi GBM Final Real-time Localization
  9. GRB 190824A: Swift-XRT refined Analysis
  10. GRB 190824A: Fermi GBM observation
  11. Fermi trigger No 588350802 Global MASTER-Net observations report
  12. Fermi GBM-190816: Updated localization of subthreshold GRB-GW candidate
  13. GRB 190821A: Swift-BAT refined analysis
  14. GRB 190824A: Swift detection of a burst
  15. GRB 190824A: Fermi GBM Final Real-time Localization
  16. Fermi trigger No 588185734 Global MASTER-Net observations report
  17. Fermi GBM-190816: Coverage and upper limits from MAXI/GSC observations
  18. Fermi trigger No 588115134 Global MASTER-Net observations report
  19. GRB 190821A: Swift/UVOT Upper Limits
  20. GRB 190821A: MASTER VWFC syncronous optical observations
  21. Fermi GBM-190816: MASTER-Net optical observation report
  22. GRB 190821A: Swift-XRT refined Analysis
  23. LIGO/Virgo S190822c: Retraction of GW compact binary merger candidate
  24. LIGO/Virgo S190822c: CLU/NED Galaxies in the 50% Localization Volume
  25. LIGO/Virgo S190822c Global MASTER-Net observations report
  26. GRB 190821A: Fermi GBM observation
  27. Fermi GBM-190816: Upper Limits from Swift/BAT Observations
  28. GRB 190821A: MASTER do not see any afterglow candidate
  29. GRB 190821A: T60 Les Makes optical detection of the afterglow
  30. Fermi GBM-190816: Four additional candidates from the Zwicky Transient Facility
  31. Swift GRB190821.72 Global MASTER-Net observations report
  32. Fermi trigger No 588100239 Global MASTER-Net observations report
  33. GRB 190821A: Swift detection of a burst
  34. Fermi GBM-190816: No counterpart candidates in Fermi-LAT observations
  35. Fermi GBM-190816: AGILE in SAA at T0
  36. Fermi GBM-190816: ZTF19abqanpy 10.4m GTC spectroscopy
  37. Fermi GBM-190816: One candidate counterpart from the Zwicky Transient Facility
  38. LIGO/Virgo GBM-190816: no counterpart candidates in the Swift/BAT Observations
  39. Fermi GBM-190816: No counterpart candidates in HAWC observations
  40. LIGO/Virgo S190814bv: No neutrino candidates at Pierre Auger Observatory
  41. Fermi GBM-190816+LIGO/Virgo : no neutrino counterpart candidate in ANTARES search
  42. Fermi GBM-190816: A subthreshold GRB candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  43. GRB 190816A: Swift-BAT refined analysis
  44. IceCube-190819A: Upper limits from Fermi-GBM Observations
  45. LIGO/Virgo S190814bv: No strong counterpart candidates in Swift/XRT observations
  46. LIGO/Virgo S190814bv: Not observable by CALET
  47. Fermi trigger No 587775150 Global MASTER-Net observations report
  48. GRB 190817A: Fermi GBM Final Real-time Localization
  49. LIGO/Virgo S190814bv: Fermi-LAT search for a high-energy gamma-ray counterpart
  50. LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
  51. Baksan Neutrino Observatory Alert 190817.35 Global MASTER-Net observations report
  52. Baksan Neutrino Observatory Alert 190816.83 Global MASTER-Net observations report
  53. GRB 190816A: Swift detection of a burst
  54. LIGO/Virgo S190816i: Retraction of GW compact binary merger candidate
  55. LIGO/Virgo S190814bv: Upper limits from Insight-HXMT/HE observations
  56. GRB 190813A: Insight-HXMT/HE detection
  57. GRB 190814A: Insight-HXMT/HE detection
  58. Fermi trigger No 587505927 Global MASTER-Net observations report
  59. LIGO/Virgo S190814bv Global MASTER-Net observations report
  60. LIGO/Virgo S190814bv: No counterpart candidates in KAIT observations
  61. LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
  62. LIGO/Virgo S190814bv: No counterpart candidates in the Swift/BAT Observations
  63. LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
  64. IPN triangulation of GRB 190813A (short)
  65. LIGO/Virgo S190814bv: Coverage and upper limits from MAXI/GSC observations
  66. LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
  67. LIGO/Virgo S190814bv Global MASTER-Net observations report
  68. LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
  69. GRB 190814A: Fermi GBM Final Real-time Localization
  70. Fermi trigger No 587392154 Global MASTER-Net observations report
  71. GRB 190813A: Fermi GBM Final Real-time Localization
  72. IPN triangulation of GRB 190805B
  73. HAWC-190806A: Upper limits from Insight-HXMT/HE observations
  74. FRB 190806: MASTER optical observation
  75. Konus-Wind observation of GRB 190810A
  76. IPN triangulation of GRB 190810A (short)
  77. Fermi trigger No 587084236 Global MASTER-Net observations report
  78. GRB 190810A: Fermi GBM Final Real-time Localization
  79. HAWC-190806A: Upper limits from Fermi-GBM Observations
  80. GRB 190726A: Insight-HXMT/HE detection
  81. LIGO/Virgo S190808ae: Retraction of GW compact binary merger candidate
  82. LIGO/Virgo S190808ae: Coverage and upper limits from MAXI/GSC observations
  83. LIGO/Virgo S190808ae: CLU/NED Galaxies in the 50% Localization Volume
  84. LIGO/Virgo S190808ae: No counterpart candidates in HAWC observations
  85. LIGO/Virgo S190808ae: One Coincident Neutrino Candidate from IceCube Search
  86. LIGO/Virgo S190808ae Global MASTER-Net observations report
  87. GRB 190808B: BALROG localization (Fermi Trigger 586980202 / GRB 190808752)
  88. Fermi trigger No 586980202 Global MASTER-Net observations report
  89. GRB 190808B: Fermi GBM Final Real-time Localization
  90. GRB 190808A: Fermi GBM Final Real-time Localization
  91. Fermi trigger No 586896678 Global MASTER-Net observations report
  92. Alert from the HAWC Burst Monitor
  93. HAWC Alert 190806.56 Global MASTER-Net observations report
  94. Fermi trigger No 586788607 Global MASTER-Net observations report
  95. Fermi trigger No 586800758 Global MASTER-Net observations report
  96. GRB 190806A: Fermi GBM Final Real-time Localization
  97. Fermi trigger No 586676451 Global MASTER-Net observations report
  98. GRB 190805B: Fermi GBM detection
  99. Konus-Wind observation of GRB 190731A
  100. GRB 190805B: BALROG localization (Fermi Trigger 586673165 / GRB 190805199)

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