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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

635 results found.

  1. LIGO/Virgo S191220af: Global MASTER-Net observations report
  2. Konus-Wind observation of GRB 191218A
  3. LIGO/Virgo S191216ap: Global MASTER-Net observations report
  4. LIGO/Virgo S191212q: Global MASTER-Net observations report
  5. Fermi trigger No 596808579: Global MASTER-Net observations report
  6. GRB 191106A: Swift-BAT refined analysis
  7. GRB 191031D: Swift-BAT refined analysis
  8. GRB 191031C: Swift-BAT refined analysis
  9. GRB 191031A: Swift-BAT refined analysis
  10. TESS Detection of the Optical Emission from the Possible Untriggered GRB Associated with ZTF19abvizsw
  11. Konus-Wind observation of GRB 191004B
  12. GRB 191004A: Swift-BAT refined analysis
  13. LIGO/Virgo S190930t: J-GEM follow-up observation for Swift J221951-484240
  14. LIGO/Virgo S190930s: No counterpart candidates in KAIT observations
  15. Update to the Fermi GBM Localizations
  16. LIGO/Virgo S190910h: Identification of a GW compact binary merger candidate
  17. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  18. LIGO/Virgo S190901ap : GRAWITA photometric observation of candidate ZTFabvizsw and GCN 25618 revision
  19. LIGO/Virgo S190901ap: Upper limits from CALET observations.
  20. LIGO/Virgo S190901ap: Upper limits from Insight-HXMT/HE observations
  21. LIGO/Virgo S190901ap: Upper limits from Fermi-GBM Observations
  22. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  23. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  24. Integral GRB190828.78 Global MASTER-Net observations report
  25. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  26. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  27. LIGO/Virgo S190718y: No counterpart candidates in CNEOST
  28. Fermi trigger No 585007213 Global MASTER-Net observations report
  29. Fermi trigger No 584264100 Global MASTER-Net observations report
  30. LIGO/Virgo S190706ai: No counterpart candidates in KAIT observations
  31. Swift GRB190631. Global MASTER-Net observations report
  32. LIGO/Virgo S190521r: CNEOST follow-up observations
  33. Fermi GRB190520.6 Global MASTER-Net observations report
  34. LIGO/Virgo S190517h: CALET Observations
  35. LIGO/Virgo S190517h: INTEGRAL prompt observation
  36. LIGO/Virgo S190517h: INTEGRAL/SPI-ACS prompt observation
  37. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  38. LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
  39. GRB 190427A, Swift-BAT refined analysis
  40. LIGO/Virgo S190426c: CNEOST Optical Observations
  41. LIGO/Virgo S190425z: CNEOST Optical Observations
  42. LIGO/Virgo S190426c: SAO optical observation
  43. Fermi GRB190415.17 Global MASTER-Net observations report
  44. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  45. Swift detection of LS I +61 303
  46. IceCube-190221A: Swift-XRT Follow-up Observations
  47. GRB 190203A: MASTER OT detection
  48. Konus-Wind observation of GRB 190114C
  49. SWIFT GRB190106.57 Global MASTER-Net OT detection
  50. GRB 181126A: Swift/UVOT Upper Limits
  51. GRB 181027A: Fermi GBM detection
  52. GRB 181020A: Swift-XRT refined Analysis
  53. GRB 181010A: REM optical and NIR afterglow detection
  54. Konus-Wind observation of GRB 180828A
  55. GRB 180728B: MASTER optical observations short GRB IPN error box
  56. GRB 180728B: Fermi GBM detection
  57. GRB 180728A: MASTER OT (= new object) detection
  58. GRB 180722A: MASTER second inspection
  59. GRB 180720B: MASTER Global Net OT observations
  60. FRB 180714: MASTER optical inspection of the Fast Rado Burst Transient
  61. GRB 180718A: Fermi GBM detection
  62. Konus-Wind observation of GRB 180623A
  63. GRB 180623A: Swift detection of a burst
  64. GRB 180618A: MASTER OT observation (a short GRB with extended emission)
  65. GRB 180605A: Fermi GBM observation
  66. Konus-Wind observation of GRB 180523A
  67. GRB 180504A: Swift-BAT refined analysis
  68. Konus-Wind observation of GRB 180427A
  69. Konus-Wind observation of GRB 180316A
  70. GRB 180325A: Swift-XRT refined Analysis
  71. GRB 180224A: Swift/UVOT Detection
  72. Konus-Wind observation of GRB 180111A
  73. GRB 180113A: Swift-BAT refined analysis
  74. GRB 180102A: Swift-BAT refined analysis
  75. IceCube-171106A: Konus-Wind upper limits
  76. GRB 171209A: Swift-BAT refined analysis
  77. GRB 171112A: MAXI/GSC detection
  78. IceCube-171106A: Swift Observations
  79. GRB 171027A, Swift-BAT refined analysis
  80. Swift trigger 781740: Further analysis from Swift and Fermi/GBM
  81. Numerous Fermi-GBM Subthreshold Notices are due to Swift J0243.6+6
  82. Swift Trigger 775946 is a Galactic transient, not GRB 171003
  83. GRB 171003A: LT early optical observations
  84. GRB 170903A: Swift-BAT refined analysis
  85. Konus-Wind observation of GRB 170822A
  86. LIGO/Virgo G298048: ATCA observations of candidate host galaxies
  87. Konus-Wind observation of GRB 170728B
  88. GRB 170714A, Swift-BAT refined analysis
  89. Fermi GBM Detection of possible burst from AXP 4U 0142+61
  90. GRB 170710B: Fermi GBM observation
  91. Konus-Wind observation of GRB 170705A
  92. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  93. GRB 170524A: Swift-BAT refined analysis
  94. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  95. GRB 170405A: Swift detection of a burst with an optical counterpart
  96. LIGO/Virgo G270580: optical observations and classification of PS and MASTER sources
  97. LIGO/Virgo G275697: Updated localization from LIGO data
  98. LIGO/Virgo G275697: Swift-XRT sources
  99. Konus-Wind observation of GRB 170206A
  100. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients

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