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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
  1. LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
  2. IPN triangulation of GRB 190409B (short)
  3. IceCube-190331A: Swift-XRT Follow-up Observations
  4. GRB 190409A: ground analysis reveals a likely spurious event
  5. LIGO/Virgo S190408an: MASTER OT J231043.63+470956.4 BOOTES-4 and 10.4m GTC follow-up observations
  6. LIGO/Virgo S190408an: MAXI/GSC Observations
  7. LIGO/Virgo S190408an: GRAWITA optical observations of MASTER OT J231043.63+470956.4
  8. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  9. LIGO/Virgo S190408an: CALET Observations
  10. LIGO/Virgo S190408an: TMTS Optical Observation
  11. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  12. LIGO/Virgo S190408an: HMT optical observations
  13. LIGO/Virgo S190408an: MASTER 3 OT's more detection
  14. Konus-Wind observation of GRB 190404B
  15. LIGO/Virgo ST190408an: Fermi-LAT search for a high-energy gamma-ray counterpart
  16. GRB 190409A: Swift detection of a possible burst
  17. LIGO-Virgo S190408an: further AGILE GRID observations after T0
  18. LIGO/Virgo S190408an: SAGUARO follow-up observations
  19. LIGO/Virgo S190408an: MASTER OT is 27 day old ATLAS SN candidate and unrelated
  20. LIGO/Virgo S190408an: Insight-HXMT/HE observation
  21. LIGO/Virgo S190408an: MASTER OT detection
  22. LIGO/Virgo S190408an: Swift/BAT data search
  23. LIGO/Virgo S190408an: KMTNet observation
  24. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  25. GRB 140408A: MAXI/GSC detection
  26. LIGO-Virgo S190408an: AGILE GRID observations
  27. LIGO/Virgo S190408an: MASTER Global Robotic Net optical observations
  28. LIGO/Virgo S190408an: Identification of a GW binary merger candidate
  29. Search for neutrino counterparts to GW candidate S190408an with IceCube
  30. LIGO-Virgo S190408an: HAWC follow-up
  31. INTEGRAL observation of S190408an
  32. LIGO/Virgo S190408an: Fermi GBM Observation
  33. LIGO-Virgo GW S190408an: J-GEM optical/NIR follow-up observations
  34. LIGO-Virgo S190408an: AGILE MCAL observations
  35. GRB 190404C: Swift-XRT afterglow detection
  36. Fermi Gamma-ray Burst Monitor trigger 576420743/190408536 is not a GRB
  37. Fermi TriggNum 576054086 (GRB 1904204.29) / MASTER OT J071404.52+550304.2: CrAO optical observations
  38. Fermi Trigger 576356086 / GRB 190407788 / : BALROG localization
  39. Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
  40. Fermi Trigger 576346051 / GRB 190407672 / GRB 190407A: BALROG localization
  41. GRB190404C: Counterpart retraction
  42. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  43. GRB 190404C: Swift-XRT observations
  44. GRB 190331C: AstroSat CZTI detection
  45. Swift GRB 190331B: Further Swift-XRT observations
  46. GRB190404C: GROWTH-India discovery of optical counterpart
  47. GRB 190404B: Tiled Swift observations
  48. GRB 140404C: MAXI/GSC detection
  49. GRB 140404B: MAXI/GSC detection
  50. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  51. Trigger 896552: Swift detection of PSR B1055-52
  52. LIGO/Virgo: Announcing the start of Observing Run 3 (O3) and the beginning of the public gravitational-wave alert era
  53. Konus-Wind observation of GRB 190329A
  54. GRB 190331B: BOOTES-3/YA optical observations
  55. GRB 190326B: AstroSat CZTI detection
  56. GRB 190331B: Swift observations of a ground-detected burst
  57. Fermi-LAT Gamma-ray Observations of IceCube-190331A
  58. Search for additional neutrino events from the direction of IceCube-190331A with IceCube
  59. GRB 190401A: Insight-HXMT/HE detection
  60. GRB 190331C: Insight-HXMT/HE detection
  61. GRB 190331A: Insight-HXMT/HE detection
  62. GRB 190330A: Insight-HXMT/HE detection
  63. IceCube-190331A: MASTER optical follow-up observations
  64. GRB 190329A: CALET Gamma-Ray Burst Monitor detection
  65. GRB 190331A: Fermi GBM detection
  66. GRB 190331B: Swift ToO observations
  67. GRB 190331A, Swift-BAT refined analysis
  68. IPN Triangulation of GRB 190329A (long/bright)
  69. IceCube-190331A - IceCube observation of a high-energy neutrino candidate event
  70. GRB 190331A: Swift detection of a burst
  71. Fermi Trigger 575656777 / GRB 190330694 / GRB 190330A: BALROG localization
  72. GRB 190323A: AstroSat CZTI detection
  73. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  74. GRB 190326A: 2.2m CAHA telescope optical limit
  75. Swift Trigger 895503 is not a GRB
  76. Swift Trigger 895479: Detection of GRO J2058+42
  77. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  78. GRB 190326B: Insight-HXMT/HE detection
  79. GRB 190326A: Insight-HXMT/HE detection
  80. Swift Trigger 895257: Detection of GRO J2058+42 in outburst
  81. GRB 190326A: MITSuME Okayama optical upper limits
  82. Konus-Wind observation of GRB 190324A
  83. GRB 190324A: Swift/UVOT Observations
  84. GRB 190326B: Fermi GBM detection
  85. GRB 190324B: Insight-HXMT/HE detection
  86. GRB 190324A: Insight-HXMT/HE detection
  87. Fermi Trigger 575278303 / GRB 190326314 / GRB190326B: BALROG localization
  88. GRB 190326A: Swift detection of a short burst
  89. Fermi Trigger 575251142 / GRB 190325999 / GRB 190325A: BALROG localization
  90. GRB 190324A: Swift-BAT refined analysis
  91. GRB 190324A: CALET Gamma-Ray Burst Monitor detection
  92. GRB 190323A: Insight-HXMT/HE detection
  93. GRB 190324A: Swift-XRT refined Analysis
  94. GRB190324A: MASTER OT observations
  95. GRB 190324A: Fermi GBM observation
  96. GRB 190324A: Enhanced Swift-XRT position
  97. Further Chandra observations of GW170817 ~581-583 days since merger
  98. GRB 190324A: VLT/X-shooter redshift
  99. GRB 190321A: Insight-HXMT/HE detection
  100. GRB 190324A: Swift-XRT observations

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