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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"

3360 results found.

  1. Fermi GRB 241207A: Global MASTER-Net observations report
  2. Fermi GRB 241204A: Global MASTER-Net observations report
  3. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  4. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  5. EP241201a: Global MASTER-Net observations report
  6. EP241126a: 1.6m Mephisto Optical Upper Limits
  7. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  8. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  9. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  10. Swift GRB 241128A: Global MASTER-Net observations report
  11. GRB 241128A: LCO optical detection
  12. GRB 241128A: 1.5m OSN optical afterglow detection
  13. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  14. Fermi trigger No 754492985: Global MASTER-Net observations report
  15. The EP-WXT trigger 01709125191 is not a real source
  16. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  17. Swift GRB241127.91: Global MASTER-Net OT detection
  18. IceCube Alert 241127.59: Global MASTER-Net observations report
  19. GRB 241120A: Mondy and AbAO optical observations
  20. GRB 241112B: Mephisto further optical observations
  21. Fermi GRB 241118A: Global MASTER-Net observations report
  22. EP241115a: Global MASTER-Net observations report
  23. Fermi GRB 241114A: Global MASTER-Net observations report
  24. EP241113a: Global MASTER-Net observations report
  25. EP241113b: Global MASTER-Net observations report
  26. Fermi GRB 241112A: Global MASTER-Net observations report
  27. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  28. Fermi trigger No 752878030: Global MASTER-Net observations report
  29. Integral GRB241109.89: Global MASTER-Net observations report
  30. GRB 241105A: EP-FXT follow-up observations
  31. GRB 241025A: LBT optical observations
  32. Fermi GRB 241105A: Global MASTER-Net observations report
  33. Fermi GRB 241104A: Global MASTER-Net observations report
  34. EP241103a: EP observation update
  35. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  36. S241102cy: Identification of a GW compact binary merger candidate
  37. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  38. GRB 241030A: further SAO RAS optical observations
  39. GRB 241030B: Montarrenti Observatory optical upper limit
  40. Fermi trigger No 752083996: Global MASTER-Net observations report
  41. Fermi trigger No 752006065: Global MASTER-Net observations report
  42. GRB 241030B: BTA observations
  43. GRB 241026A: LBT optical observations
  44. GRB 241030A : MITSuME Akeno optical afterglow detection
  45. GRB 241026A: SAO RAS optical observations
  46. EP241021a: SAO RAS observations of rebrightening
  47. GRB 241029A: AKO Optical Afterglow Detection
  48. EP241021a: Gemini-South detection of optical rebrightening
  49. GRB 241025A: SAO RAS optical observations
  50. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  51. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  52. Fermi GRB 241026A: Global MASTER-Net observations report
  53. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  54. Fermi trigger No 751554401: Global MASTER-Net observations report
  55. EP241021a: optical follow-up observations with the Liverpool Telescope
  56. GRB 241025A: DDOTI Afterglow detection
  57. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  58. IceCube-Cascade 241019A: Upper limits from a search for additional neutrino events in IceCube
  59. GRB 241018A: SVOM/VT follow-up and optical candidate
  60. GRB 241017A: GROWTH-India Telescope optical upper limit
  61. Fermi trigger No 750788395: Global MASTER-Net observations report
  62. LIGO/Virgo/KAGRA S241011k: Identification of a GW compact binary merger candidate
  63. Fermi trigger No 750211959: Global MASTER-Net observations report
  64. Fermi trigger No 750291012: Global MASTER-Net observations report
  65. Fermi GRB 241010B: Global MASTER-Net observations report
  66. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  67. GRB 241006A: Swift/UVOT Upper Limits
  68. GRB 241001A: Swift-XRT afterglow detection
  69. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  70. GRB 241001A: correction to GCN 37667
  71. Fermi GRB 241002B: Global MASTER-Net observations report
  72. GRB 241001A: Swift-XRT observations
  73. GRB241001A: optical afterglow candidate
  74. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  75. Fermi GRB 240930B: Global MASTER-Net observations report
  76. Fermi trigger No 749339671: Global MASTER-Net observations report
  77. Fermi Gamma-ray Burst Monitor trigger 749191601/240928199 is not a GRB
  78. EP240918b and EP240918c: EP-FXT follow-up observations
  79. Konus-Wind detection of GRB 240918B
  80. EP240913a/GRB 240913C: 1.6m Mephisto observations
  81. EP240919a / GRB 240919A: REM optical and NIR upper limits
  82. EP EP240918a: Global MASTER-Net observations report
  83. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  84. EP240908a: Updates on the WXT detection result around the trigger time
  85. GRB 240905E: GIT optical upper limit
  86. GRB 240905B: Fermi-LAT detection
  87. Fermi trigger No 746923430: Global MASTER-Net observations report
  88. GRB 240828B: Mephisto optical upper limit
  89. GRB 240828B: SVOM/C-GFT optical upper limit
  90. Fermi trigger No 746587425: Global MASTER-Net observations report
  91. GRB 240828A: Fermi GBM Observation
  92. GRB 240629A: First GRB Detected by BurstCube
  93. GRB 240825A: further SAO RAS optical observations
  94. GRB 240829A: Swift detection of a burst
  95. GRB 240828A: Fermi-LAT detection
  96. LAT GRB240828.62: Global MASTER-Net observations report
  97. GRB 240828A: AstroSat CZTI detection of a long burst
  98. Fermi GRB 240828A: Global MASTER-Net observations report
  99. Fermi trigger No 746438824: Global MASTER-Net observations report
  100. SVOM GRB 240821A: optical afterglow discovery

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