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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"

27305 results found.

  1. LIGO/Virgo S190828l: No counterpart candidates in HAWC observations
  2. LIGO/Virgo S190828j: No counterpart candidates in HAWC observations
  3. Fermi trigger No 588597173 Global MASTER-Net observations report
  4. Fermi GBM-190816: Eight additional candidates from the Zwicky Transient Facility
  5. GRB 190827A: BALROG localization (Fermi Trigger 588597173 / GRB 190827467)
  6. GRB 190827A: Fermi GBM Final Real-time Localization
  7. GRB 190824A, Swift-BAT refined analysis
  8. GRB 190824A: Swift/UVOT Upper Limits
  9. Fermi trigger No 588398821 Global MASTER-Net observations report
  10. LIGO/Virgo S190814bv: MASTER prediscovery and postdiscovery observations DECam candidate DG19wxnjc/AT2019npv field
  11. GRB 190825A: Fermi GBM Final Real-time Localization
  12. GRB 190824A: Swift-XRT refined Analysis
  13. GRB 190824A: Fermi GBM observation
  14. Fermi trigger No 588350802 Global MASTER-Net observations report
  15. Fermi GBM-190816: Updated localization of subthreshold GRB-GW candidate
  16. GRB 190821A: Swift-BAT refined analysis
  17. GRB 190824A: Swift detection of a burst
  18. GRB 190824A: Fermi GBM Final Real-time Localization
  19. Fermi trigger No 588185734 Global MASTER-Net observations report
  20. Fermi GBM-190816: Coverage and upper limits from MAXI/GSC observations
  21. Fermi trigger No 588115134 Global MASTER-Net observations report
  22. GRB 190821A: Swift/UVOT Upper Limits
  23. GRB 190821A: MASTER VWFC syncronous optical observations
  24. Fermi GBM-190816: MASTER-Net optical observation report
  25. GRB 190821A: Swift-XRT refined Analysis
  26. LIGO/Virgo S190822c: Retraction of GW compact binary merger candidate
  27. LIGO/Virgo S190822c: CLU/NED Galaxies in the 50% Localization Volume
  28. LIGO/Virgo S190822c Global MASTER-Net observations report
  29. GRB 190821A: Fermi GBM observation
  30. Fermi GBM-190816: Upper Limits from Swift/BAT Observations
  31. GRB 190821A: MASTER do not see any afterglow candidate
  32. GRB 190821A: T60 Les Makes optical detection of the afterglow
  33. Fermi GBM-190816: Four additional candidates from the Zwicky Transient Facility
  34. Swift GRB190821.72 Global MASTER-Net observations report
  35. Fermi trigger No 588100239 Global MASTER-Net observations report
  36. GRB 190821A: Swift detection of a burst
  37. Fermi GBM-190816: No counterpart candidates in Fermi-LAT observations
  38. Fermi GBM-190816: AGILE in SAA at T0
  39. Fermi GBM-190816: ZTF19abqanpy 10.4m GTC spectroscopy
  40. Fermi GBM-190816: One candidate counterpart from the Zwicky Transient Facility
  41. LIGO/Virgo GBM-190816: no counterpart candidates in the Swift/BAT Observations
  42. Fermi GBM-190816: No counterpart candidates in HAWC observations
  43. LIGO/Virgo S190814bv: No neutrino candidates at Pierre Auger Observatory
  44. Fermi GBM-190816+LIGO/Virgo : no neutrino counterpart candidate in ANTARES search
  45. Fermi GBM-190816: A subthreshold GRB candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  46. GRB 190816A: Swift-BAT refined analysis
  47. IceCube-190819A: Upper limits from Fermi-GBM Observations
  48. LIGO/Virgo S190814bv: No strong counterpart candidates in Swift/XRT observations
  49. LIGO/Virgo S190814bv: Not observable by CALET
  50. Fermi trigger No 587775150 Global MASTER-Net observations report
  51. GRB 190817A: Fermi GBM Final Real-time Localization
  52. LIGO/Virgo S190814bv: Fermi-LAT search for a high-energy gamma-ray counterpart
  53. LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
  54. Baksan Neutrino Observatory Alert 190817.35 Global MASTER-Net observations report
  55. Baksan Neutrino Observatory Alert 190816.83 Global MASTER-Net observations report
  56. GRB 190816A: Swift detection of a burst
  57. LIGO/Virgo S190816i: Retraction of GW compact binary merger candidate
  58. LIGO/Virgo S190814bv: Upper limits from Insight-HXMT/HE observations
  59. GRB 190813A: Insight-HXMT/HE detection
  60. GRB 190814A: Insight-HXMT/HE detection
  61. Fermi trigger No 587505927 Global MASTER-Net observations report
  62. LIGO/Virgo S190814bv Global MASTER-Net observations report
  63. LIGO/Virgo S190814bv: No counterpart candidates in KAIT observations
  64. LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
  65. LIGO/Virgo S190814bv: No counterpart candidates in the Swift/BAT Observations
  66. LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
  67. IPN triangulation of GRB 190813A (short)
  68. LIGO/Virgo S190814bv: Coverage and upper limits from MAXI/GSC observations
  69. LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
  70. LIGO/Virgo S190814bv Global MASTER-Net observations report
  71. LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
  72. GRB 190814A: Fermi GBM Final Real-time Localization
  73. Fermi trigger No 587392154 Global MASTER-Net observations report
  74. GRB 190813A: Fermi GBM Final Real-time Localization
  75. IPN triangulation of GRB 190805B
  76. HAWC-190806A: Upper limits from Insight-HXMT/HE observations
  77. FRB 190806: MASTER optical observation
  78. Konus-Wind observation of GRB 190810A
  79. IPN triangulation of GRB 190810A (short)
  80. Fermi trigger No 587084236 Global MASTER-Net observations report
  81. GRB 190810A: Fermi GBM Final Real-time Localization
  82. HAWC-190806A: Upper limits from Fermi-GBM Observations
  83. GRB 190726A: Insight-HXMT/HE detection
  84. LIGO/Virgo S190808ae: Retraction of GW compact binary merger candidate
  85. LIGO/Virgo S190808ae: Coverage and upper limits from MAXI/GSC observations
  86. LIGO/Virgo S190808ae: CLU/NED Galaxies in the 50% Localization Volume
  87. LIGO/Virgo S190808ae: No counterpart candidates in HAWC observations
  88. LIGO/Virgo S190808ae: One Coincident Neutrino Candidate from IceCube Search
  89. LIGO/Virgo S190808ae Global MASTER-Net observations report
  90. GRB 190808B: BALROG localization (Fermi Trigger 586980202 / GRB 190808752)
  91. Fermi trigger No 586980202 Global MASTER-Net observations report
  92. GRB 190808B: Fermi GBM Final Real-time Localization
  93. GRB 190808A: Fermi GBM Final Real-time Localization
  94. Fermi trigger No 586896678 Global MASTER-Net observations report
  95. Alert from the HAWC Burst Monitor
  96. HAWC Alert 190806.56 Global MASTER-Net observations report
  97. Fermi trigger No 586788607 Global MASTER-Net observations report
  98. Fermi trigger No 586800758 Global MASTER-Net observations report
  99. GRB 190806A: Fermi GBM Final Real-time Localization
  100. Fermi trigger No 586676451 Global MASTER-Net observations report

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