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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36144 results found.

  1. GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations
  2. GRB 190427A: NOT optical observations
  3. GRB 190427A: Swift-XRT observations
  4. GRB 190427A: Swift detection of a short burst
  5. LIGO/Virgo S190426c: Swift/BAT Counterpart Search
  6. LIGO/Virgo S190426c: Fermi GBM Observations
  7. LIGO/Virgo S190426c: INTEGRAL prompt observation
  8. LIGO/Virgo S190425z: Insight-HXMT/HE observation
  9. LIGO/Virgo S190425z: Fermi GBM Observations
  10. LIGO/Virgo S190425z: Swift/BAT Counterpart Search
  11. LIGO/Virgo S190425z: INTEGRAL IBIS prompt observation
  12. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  13. LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation
  14. GRB 190424A: Swift-BAT refined analysis
  15. GRB 190424A: Swift detection of a burst
  16. GRB 190422A: Fermi GBM detection
  17. GRB 190422A: Swift/UVOT Upper Limits
  18. LIGO/Virgo S190421ar: Swift/BAT Counterpart Search
  19. GRB 190422A: Swift-BAT refined analysis
  20. GRB 190422A: Swift-XRT refined Analysis
  21. LIGO/Virgo S190421ar: INTEGRAL prompt observation
  22. GRB 190422A: Enhanced Swift-XRT position
  23. GRB 190422A: Swift detection of a burst
  24. LIGO/Virgo S190421ar: Fermi-GBM Observations
  25. Konus-Wind observation of GRB 190415A
  26. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  27. Fermi Trigger 577360542 / GRB 190419414 / GRB190419A: BALROG localization
  28. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  29. GRB 190326A: Swift XRT and UVOT follow-up observations
  30. IPN Triangulation of GRB 190415A
  31. GRB 190415A: Insight-HXMT/HE detection
  32. Fermi Trigger 576994194 / GRB 190415173 / : BALROG localization
  33. GRB 190407B: AstroSat CZTI detection
  34. Corrections: GRB 190404A (not 140404B ) and GRB 190404B (not 140404C)
  35. GRB 190411A: AstroSat CZTI detection
  36. GRB 190411A: Insight-HXMT/HE detection
  37. LIGO/Virgo S190412m: Swift/BAT data search
  38. LIGO/Virgo S190412m: Fermi-GBM Observations
  39. LIGO/Virgo S190412m: Insight-HXMT/HE observation
  40. INTEGRAL prompt observation of S190412m
  41. IPN triangulation of GRB 190409B (short)
  42. GRB 190409A: ground analysis reveals a likely spurious event
  43. LIGO/Virgo S190408an: MAXI/GSC Observations
  44. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  45. Konus-Wind observation of GRB 190404B
  46. GRB 190409A: Swift detection of a possible burst
  47. LIGO/Virgo S190408an: Insight-HXMT/HE observation
  48. LIGO/Virgo S190408an: Swift/BAT data search
  49. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  50. GRB 140408A: MAXI/GSC detection
  51. INTEGRAL observation of S190408an
  52. GRB 190404C: Swift-XRT afterglow detection
  53. Fermi Gamma-ray Burst Monitor trigger 576420743/190408536 is not a GRB
  54. Fermi TriggNum 576054086 (GRB 1904204.29) / MASTER OT J071404.52+550304.2: CrAO optical observations
  55. Fermi Trigger 576356086 / GRB 190407788 / : BALROG localization
  56. Fermi Trigger 576346051 / GRB 190407672 / GRB 190407A: BALROG localization
  57. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  58. GRB 190404C: Swift-XRT observations
  59. GRB 190331C: AstroSat CZTI detection
  60. Swift GRB 190331B: Further Swift-XRT observations
  61. GRB 190404B: Tiled Swift observations
  62. GRB 140404C: MAXI/GSC detection
  63. GRB 140404B: MAXI/GSC detection
  64. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  65. Konus-Wind observation of GRB 190329A
  66. GRB 190331B: BOOTES-3/YA optical observations
  67. GRB 190326B: AstroSat CZTI detection
  68. GRB 190331B: Swift observations of a ground-detected burst
  69. GRB 190401A: Insight-HXMT/HE detection
  70. GRB 190331C: Insight-HXMT/HE detection
  71. GRB 190331A: Insight-HXMT/HE detection
  72. GRB 190330A: Insight-HXMT/HE detection
  73. GRB 190329A: CALET Gamma-Ray Burst Monitor detection
  74. GRB 190331A: Fermi GBM detection
  75. GRB 190331B: Swift ToO observations
  76. GRB 190331A, Swift-BAT refined analysis
  77. IPN Triangulation of GRB 190329A (long/bright)
  78. GRB 190331A: Swift detection of a burst
  79. Fermi Trigger 575656777 / GRB 190330694 / GRB 190330A: BALROG localization
  80. GRB 190323A: AstroSat CZTI detection
  81. GRB 190326A: 2.2m CAHA telescope optical limit
  82. Swift Trigger 895503 is not a GRB
  83. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  84. GRB 190326B: Insight-HXMT/HE detection
  85. GRB 190326A: Insight-HXMT/HE detection
  86. GRB 190326A: MITSuME Okayama optical upper limits
  87. Konus-Wind observation of GRB 190324A
  88. GRB 190324A: Swift/UVOT Observations
  89. GRB 190326B: Fermi GBM detection
  90. GRB 190324B: Insight-HXMT/HE detection
  91. GRB 190324A: Insight-HXMT/HE detection
  92. Fermi Trigger 575278303 / GRB 190326314 / GRB190326B: BALROG localization
  93. GRB 190326A: Swift detection of a short burst
  94. Fermi Trigger 575251142 / GRB 190325999 / GRB 190325A: BALROG localization
  95. GRB 190324A: Swift-BAT refined analysis
  96. GRB 190324A: CALET Gamma-Ray Burst Monitor detection
  97. GRB 190323A: Insight-HXMT/HE detection
  98. GRB 190324A: Swift-XRT refined Analysis
  99. GRB190324A: MASTER OT observations
  100. GRB 190324A: Fermi GBM observation

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